September 11, 2021

Flooding Rains Likely In Texas; Watching Five Different Tropical Disturbances In The Atlantic


A tropical disturbance in the Gulf of Mexico has a high chance of developing into a tropical depression over the next couple of days as it moseys near the coasts of Mexico and Texas. 

Regardless of its development, the system will bring drenching rains to coastal Texas, with totals possibly climbing into the double digits for some by the end of the week.

We're also watching four other systems out in the Atlantic, each with varying chances for development heading into next week.

Gulf System + Texas Flooding


The National Hurricane Center (NHC) gives the Gulf disturbance a 90% chance of developing into a tropical depression by Monday, which is a decent display of confidence from the agency's expert forecasters.

The disturbance could become Tropical Storm Nicholas before it reaches land, but that's a big if, and it could have some significant impacts across the region whether or not it organizes and earns a name.

A surge of tropical moisture will sweep over the Texas coast over the next couple of days, providing a deep reserve of moisture for thunderstorms to tap into and produce torrential downpours across the region.


The Weather Prediction Center is calling for widespread rainfall totals of 4-8" across the Gulf Coast from southern Texas through central Louisiana. Higher totals are possible around Houston, Galveston, Beaumont, and Lake Charles, where someone could wind up with double-digit totals by this time next week.

Right now, it looks like the heaviest rain could fall between Sunday night to Wednesday night.

These rainfall totals are likely to change subject to the development and path of the system.  A stronger system would produce heavier rains along its path.

But either way, this has the potential to bring flooding rains to a region not particularly well-equipped to handle them. As always, the best advice is to remember that it's impossible to tell how deep the water is before it's too late. It's never worth risking your life or the lives of your rescuers to try to drive through floodwaters.

Four Other Atlantic Disturbances


Friday was the climatological peak of the hurricane season. Storms don't follow our puny calendars, of course, but this is about the time of the year when favorable atmospheric conditions coincide with sea surface temperatures warmed by the sultry heat of a long summer.

Even so, it's still jarring to see the NHC's tropical weather outlook map lit up like a Christmas tree. Aside from the impending tropical depression in the southwestern Gulf of Mexico, we have to watch four other systems out in the Atlantic.

Let's go from most interesting to least interesting...

30% Near The Bahamas

A disturbance could develop east of The Bahamas in a couple of days. If this system develops, it'll be worth watching for tropical development because of its proximity to the East Coast. An upper-level ridge is expected to develop over the region this week. Ridges tend to act like guardrails that, for lack of a better term, can trap tropical systems beneath them. 

It's nothing to worry about just yet, but file it away in the back of your mind. Spend the next few days thinking about what supplies you'd need to get through a power outage just in case something spins up and heads your way.

50% and 40% Near Africa

The two areas highlighted near the Cabo Verde Islands are typical tropical waves that roll off the western coast of Africa during the height of the summer. They're a looong way out, and we'll have plenty of time to watch what happens with these two disturbances.

20% Near Iberia

We seem to get at least one of these loners every year. A low-pressure system meandering in the northeastern Atlantic Ocean has a low chance of transitioning into a tropical or subtropical system this week. They usually don't cause too much harm aside from bringing foul weather to The Azores and the Iberian Peninsula.


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September 9, 2021

A Short History of Short-Lived Tropical Storms


Tropical Storm Mindy formed and made landfall in about four hours on Wednesday afternoon. The system joins an interesting list of storms that spun up and came ashore with little notice. Here's a very short history on these very sneaky storms.

Tropical Storm Mindy (2021)

Mindy formed from a tropical disturbance we've been watching for more than a week. The disturbance first popped up in the National Hurricane Center's tropical weather outlooks on August 30th, not long after Hurricane Ida made landfall in Louisiana.

The disturbance meandered over parts of Central America and Mexico before emerging over the Gulf of Mexico this past weekend. Forecasters upped the disturbance's odds of development to 30% on Tuesday afternoon and to 60% on Wednesday afternoon.
Source: NOAA/Gibson Ridge

The system developed a closed, well-defined circulation as it approached the Florida Panhandle on Wednesday afternoon. Forecasters declared the system Tropical Storm Mindy at 4:00 p.m., and the storm made landfall near Apalachicola just after 8:00 p.m.

Storms sometimes do that. It's the peak of hurricane season and the Gulf of Mexico is warm. It doesn't take much of a nudge to send a disturbance over the edge of formation when conditions are favorable for development.

Tropical Storm Bertha (2020)

Bertha formed at 8:00 a.m. and made landfall near Charleston, S.C., at 9:30 a.m.

Blink and you missed it. I don't even have a graphic for it. It was just...there and gone. Bloop.

Tropical Storm Imelda (2019)

Forecasters declared a disturbance in the northwestern Gulf of Mexico a tropical depression at 12:00 p.m. The system became a tropical storm at 12:45 p.m. Imelda made landfall in Freeport, Texas, at 1:30 p.m.


While this was another hello/goodbye storm, the ensuing floods were well-predicted.

The remnants of Imelda stalled over parts of Texas and Louisiana and produced a tremendous amount of rain over the following days, with widespread totals of 12-24"+ common around and east of Houston, with totals approaching four feet (!!!) near Beaumont.

Tropical Storm Emily (2017)

Emily escalated quickly on July 31, 2017, as it swirled toward Florida's west coast.
Source: NOAA/Gibson Ridge
8:00 p.m.: 20% chance of formation.
2:00 a.m.: 40% chance of formation.
6:00 a.m.: Tropical Depression Six
8:00 a.m.: Tropical Storm Emily
11:10 a.m.: Landfall near Bradenton, Florida with 45 mph winds.

Tropical Storm Bill (2015)

The disturbance that became Tropical Storm Bill in June 2015 became a soap opera because of its expected wind and rain impacts in Texas as the storm took its time developing in the Gulf of Mexico.
It was obvious that the system would rapidly intensify as it approached the Texas coast, but it would happen just hours before it made landfall near Corpus Christi. 

So we waited. And waited.

The disturbance finally developed into a tropical depression at 11:00 p.m. on June 15 and made landfall on Matagorda Island as a 60 mph tropical storm 12 hours later.

The bureaucratic headache that hampered the ability to issue forecasts for future-Bill was the reason we now get "potential tropical cyclones" every once and a while.

Forecasters at the National Hurricane Center came up with the PTC designation after Bill so the agency could issue advisories, watches, and warnings for a disturbance if it's going to develop and hit quickly hit land soon after. Before then, we just had to wait and wait, which wasted critical time needed to get the word out to people in harm's way.

Hurricane Humberto (2007)

Source: NHC
One of the most memorable quicker-spinner-uppers was Hurricane Humberto in 2007. The system went from a tropical depression to a category one hurricane in about 24 hours, making landfall near Beaumont, Texas, with 85 mph winds.

The storm intensified into a hurricane 15 miles off the coast.

15 miles.

Humberto's sudden jump in intensity wasn't well predicted, and folks in the path of the storm had very little time to prepared for a full-fledged hurricane—which is less of a statement about the NHC's abilities back in 2007 than it is about a tropical system's ability to take off when it thrives over the Gulf of Mexico.

[Satellite Image: NOAA]


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September 6, 2021

Large Hurricane Larry Scrapes Bermuda This Week, Dangerous Surf/Rip Currents For U.S.


Larry is a looker. This major hurricane in the central Atlantic Ocean will scrape by Bermuda later this week—possibly bringing squally weather to the island—before approaching Newfoundland next weekend. While the storm won't affect the U.S., dangerous surf and rip currents are likely as Larry's vigorous waves reach the East Coast.

The sculpted cyclone is the third major hurricane of the 2021 Atlantic hurricane season. The National Hurricane Center's Monday morning advisory found the hurricane's maximum sustained winds holding steady around 120 mph.


A ridge of high pressure over the western Atlantic will steer Larry around its outer periphery, bringing the hurricane east of Bermuda on Thursday before allowing it to recurve and head in Newfoundland's general direction next weekend.


Larry is the first hurricane we've had this year that's a stunning, largely guilt-free gawk-fest on satellite imagery.

The hurricane almost resembles a western Pacific typhoon. Hurricane Larry has a huge eye—70 miles wide!—and a near-symmetrical core. These are called annular hurricanes, and I like to refer to them as "all eyewall" because there's not much to the storm but its eye and thick inner core. 

Forecasters expect Larry's portly stature to aid the hurricane in maintaining intensity over the next couple of days. After that, the system will begin to struggle as it enters a more unfavorable environment and picks up speed as it rounds the ridge.

The storm will lose its tropical characteristics at the end of the week and transition into an extratropical cyclone, or the "everyday" type of low-pressure system that's driven by upper-level winds and has fronts at the surface.

Even so, the storm will still have hurricane-strength winds when it passes Newfoundland's Avalon Peninsula on Friday or Saturday. Larry is already a large storm, and systems tend to grow larger as they transition from tropical to extratropical, so there's a decent chance it brings some foul weather to the region if it stays on its predicted track.

The Avalon is home to about half of Newfoundland's population (roughly a quarter of a million people), so the wind and rain could be disruptive even if the center of the storm passes far offshore.

SOURCE: NOAA

While Hurricane Larry won't come close to hitting the United States, the storm's rough surf will pose a hazard to beaches from Florida to Maine. Life-threatening rip currents are possible this week as Larry's waves reach the U.S.

Rip currents are currents that pull away from the shore. They form as a result of waves hitting the beach head-on, forcing the water to drain straight away from the coast in swift, narrow channels. Rip currents don't pull you under the water—they pull you out and away from land.

A rip current often looks like a calm spot amid a torrent of waves hitting the beach, which makes these hazardous areas alluring to visitors. If you see a curiously calm patch of water between waves, or sea foam swiftly pulling away between waves, don't go in the water, and dissuade others from going in the water as well.

The best way to avoid rip currents is to avoid going in the water when rip currents are a danger. But if you ever find yourself in a rip current, don't panic. Swim parallel to the shore until the current stops pulling you out to sea, then swim back to safety. If you can't swim, or if you don't have the energy to swim, calmly signal for help and tread water until help arrives.


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September 1, 2021

Hurricane Ida's Remnants Unleash Tornadoes, Flash Flood Emergencies In Northeast


Predictions of widespread flash flooding and an enhanced risk for tornadoes came to pass on Wednesday as the remnants of Hurricane Ida passed through the Mid-Atlantic and Northeast. Flash flood emergencies were issued across the region, including the entire New York City metro area. The system also spawned multiple strong tornadoes in Maryland and New Jersey.

This was a well-predicted event. Forecasters sounded the alarm a few days ago that this system would produce widespread and intense flash flooding in parts of the northeast, and the Storm Prediction Center had a risk for tornadoes highlighted across the affected regions for the past couple of days.

Widespread Flash Flooding

The WPC's excessive rainfall outlook for Wednesday, issued Tuesday afternoon. || SOURCE: WPC

Tropical moisture associated with the remnants of Ida flowed north on Tuesday and overran a stationary front parked over the region. This initial batch of precipitation produced drenching rains over parts of Pennsylvania, New Jersey, New York, and Connecticut, overnight Tuesday into Wednesday.

Ida's remnants then caught up with this boundary as the erstwhile tropical cyclone transitioned into a non-tropical low-pressure system.

The lift from the low and its associated fronts provided a new focal point for additional heavy showers and thunderstorms to develop on Wednesday afternoon. The intense rains continued through early Thursday morning.


These thunderstorms trained over the same areas for hours at a time, tapping into the deep reserve of tropical moisture to produce incredible, rarely seen rainfall rates for this part of the country. Central Park recorded 3.15 inches of rain in one hour between 8:51 PM and 9:51 PM.

Portions of Pennsylvania, New Jersey, and the New York City area witnessed double-digit rainfall totals by midnight on Thursday.

The torrential rains led to widespread flash flood warnings for almost the entire region, including the New York City metro area.
Many of the flash flood warnings were flash flood emergencies, enhanced wording (similar to a tornado emergency) that forecasters can use to describe widespread, life-threatening flash flooding.

This was the first time New York City had ever been included in a flash flood emergency, highlighting the high-end, historic potential of this flash flood event.

It's likely sunrise on Thursday will reveal significant damage from the flash floods across a large swath of the region.

Multiple Strong Tornadoes

The flash floods completely eclipsed the Oklahoma-style tornadoes we saw from some of the storms earlier on Wednesday afternoon.

The remnants of hurricanes are infamous for producing tornadoes as they push inland, especially systems that parallel the Appalachians after hitting the northern Gulf Coast.

Strong wind shear that's favorable for the development of tornadoes is common in the "right-front quadrant" of the storm. This is the eastern side of the storm for most systems that hit the United States.
A model-simulated sounding of the atmosphere near Wilmington, Delaware, on Wednesday afternoon. The clockwise line on the top-right graph shows strong vertical wind shear in the atmosphere, favorable for supercells that could produce tornadoes. || SOURCE: Tropical Tidbits

Winds in this part of the storm veer clockwise between the lower and mid-levels of the atmosphere, providing the strong wind shear necessary for a thunderstorm to begin rotating. As a result, we often see small supercells form in the outer bands of tropical cyclones.

The remnants of tropical cyclones (such as Ida on Wednesday) often act like a low-pressure system we'd see in the middle of the spring. Warm, humid air on the eastern side of the system provides the instability needed for thunderstorms to bubble up and thrive. These storms then tap into that rotation and go on to produce tornadoes.

We saw that situation play out as Ida passed through the region. Multiple tornadoes touched down in Virginia, Maryland, and New Jersey on Tuesday and Wednesday. 

Some of the tornadoes were downright scary, looking more like something we'd see in Oklahoma or Alabama than the Mid-Atlantic.

Annapolis, Maryland:
Mullica Hill, New Jersey:
Burlington, New Jersey:

It'll be a day or two before the National Weather Service is able to get out there and survey the damage, but it wouldn't surprise me if one or two of the tornadoes today was "significant," with a rating of EF-2 or higher.

Ida's remnants now join a long list of strong hurricanes that spawned tornado outbreaks in the days after they made landfall in the southeast.

The most infamous tropical-induced tornado outbreak in recent memory was Hurricane Ivan in 2004, which spawned more than 100 tornadoes as the system and its remnants traversed the southeast and Mid-Atlantic. One of Ivan's tornadoes produced F3 damage in Fauquier County, Virginia, just southwest of Washington, D.C.

Hurricanes Isaias, Florence, and Frances also spawned significant and memorable tornado outbreaks as they moved over the eastern states.

[Satellite Image: NOAA]

Note: I updated this post multiple times on Wednesday night to update the rainfall map and add new information.


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August 31, 2021

Tornado Threat Increases For I-95 Corridor Between D.C. And Philly On Wednesday


An enhanced risk for severe weather will exist around the Washington, Baltimore, and Philadelphia areas on Wednesday as the remnants of Hurricane Ida move through the region. There's enough wind shear that the strongest thunderstorms that form in the region could produce tornadoes.


Forecasters at the Storm Prediction Center issued an enhanced risk for severe weather—a three on the five-category scale measuring the threat for severe thunderstorms—for the I-95 corridor stretching from northern Virginia to southern New Jersey, including parts of southeastern Pennsylvania, eastern Maryland, and Delaware.

Tornadoes will be the predominant risk. Severe thunderstorms in the risk areas could also produce damaging wind gusts.

The threat will be greatest during the afternoon and evening hours on Wednesday.

While the enhanced risk area will see the best environment for tornadoes, a risk for tornadoes on Wednesday will extend as far to the south as the Charleston, S.C., area, and as far to the north as Nantucket.



Tropical Depression Ida (and soon to be "Remnants of Ida") spent Tuesday swirling over the Tennessee Valley. The system will continue heading toward the northeast over the next couple of days.

The system is undergoing extratropical transition, which means it's losing its tropical characteristics and transitioning into an everyday type of low-pressure system that's powered by upper-level winds and has surface fronts.

There's still plenty of wind shear on the eastern side of the system, which is common for landfalling tropical cyclones. This wind shear allows thunderstorms to develop rotation that can produce tornadoes.

The remnants of hurricanes that hit the Gulf Coast are infamous for the tornado potential these systems can bring to the Mid-Atlantic. If tomorrow's forecast pans out, Ida's remnants will be no exception.
SOURCE: Tropical Tidbits

The graph above reveals why there's an enhanced risk for tornadoes around the Mid-Atlantic on Wednesday.

This is a model simulation of the data we get from weather balloons, looking at temperature, moisture, and winds through a vertical slice of the atmosphere. This particular graphic is for the area around Wilmington, Delaware on Wednesday evening.

If you look at the hodograph on the top-right side of the image, you'll see a long line that hooks clockwise as it spirals out on the graph.

That tells us that winds are picking up speed and veering clockwise with height—the type of shear that makes supercell thunderstorms possible.

Make sure you have a way to receive severe weather warnings the moment they're issued. Check your cell phone's emergency alerts feature and make sure they're activated for tornadoes. Tropical-influenced tornadoes can happen quickly, and they can grow quite strong.


A threat for tornadoes isn't the only concern we'll have to deal with on Wednesday. The system's ample tropical moisture will produce widespread heavy rainfall from the Appalachians to coastal New England over the next couple of days.

Rainfall totals of 3-5" will be common, with locally higher amounts where training thunderstorms develop. This heavy rainfall will lead to a potential for flash flooding across a large stretch of the region.
SOURCE: WPC

The Weather Prediction Center issued a high risk for excessive rainfall (read: flash flooding) on Wednesday across portions of Pennsylvania, New Jersey, New York, and Connecticut. A high risk for excessive rainfall from the WPC is relatively rare, and it's indicative of high confidence in the potential for widespread flash flooding. 

Stay alert for flash flood warnings in addition to tornado warnings. Never try to drive across a flooded roadway. Many people die every year when they drive into a flood and drown. It's impossible to tell how deep the water is before it's too late.


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Ida's Remnants Are A Flash Flood Threat In The Mid-Atlantic And Northeast This Week


The remnants of once-powerful Hurricane Ida will bring a threat for flash flooding and tornadoes to much of the eastern U.S. over the next couple of days.

While the storm's winds are a mere shadow of their 150 MPH fury when the storm made landfall in Louisiana on Sunday, the system is still a major rainmaker and will lead to a threat for tornadoes through midweek.

Ida's remnants will pass over the Tennessee Valley Tuesday and Wednesday, reaching the Mid-Atlantic and Northeast by the end of the week.

A trough moving over the Great Lakes will catch up with Ida's remnants by the middle of the week. This trough will help the system redevelop into an extratropical cyclone, or your typical, everyday type of low-pressure system.

The combination of Ida's tropical moisture and all the extra lift from the trough and developing surface low is a recipe for very heavy rainfall. It's the atmospheric version of wringing out a soaked washcloth.

Source: WPC

Right now, the Weather Prediction Center has a moderate risk for excessive rainfall (read: flash flood potential) across a wide swath of the Mid-Atlantic and parts of the southern Northeast. 

The agency's latest rainfall forecast shows widespread totals of 3-5 inches falling along the path of ex-Ida. Locally higher totals are possible, especially where training thunderstorms produce high rainfall rates.

Stay alert for flash flooding during and after heavy rainfall. If any of your daily routes are prone to flooding, map out an alternate route ahead of time so you can avoid danger.

Many people die every year when they drive into a flood and drown. It's impossible to tell how deep the water is until it's too late, and sometimes there's not even a road under the water anymore. 


Flooding won't be ex-Ida's only hazard. There's still enough wind shear on the eastern side of the system to allow thunderstorms to begin rotating.

We'll see a tornado risk across parts of the southeast and Mid-Atlantic over the next couple of days. This risk is greatest in Alabama, Georgia, and the Florida Panhandle on Tuesday, but tornadoes are possible as far north as the Delmarva Peninsula through Wednesday.

Tropical tornadoes happen quickly, sometimes with reduced tornado warning lead time. Make sure your cell phone's wireless emergency alerts are activated so you can receive a tornado warning the moment one is issued.


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August 29, 2021

Ida Will Bring Strong Winds, Flooding Rain Far Inland Over The Next Few Days


Hurricane Ida made landfall in southeastern Louisiana on Sunday afternoon with maximum sustained winds of 150 mph, making this one of the most intense hurricanes to ever hit the United States. The system took its time winding down over southeastern Louisiana. Ida will weaken as it moves inland, but widespread power outages and flooding rains are likely over the next few days.

Ida joins a most unwanted list of hurricanes that rapidly intensified all the way up to landfall, a once-rare pattern that we've seen with many powerful storms—Harvey, Michael, Laura, Zeta, Sally—over the past couple of years.

The hurricane made landfall twice, first in Port Fourchon—a major oil and gas hub in the region—with 150 mph winds, then again a few hours later near Galliano with winds of 145 mph.

NWS New Orleans received a fairly reliable report from Port Fourchon of sustained winds of 149 mph with a gust to 172 mph during Ida's landfall:


Hurricane Ida took its sweet time winding down due to the brown ocean effect, the tendency for warm, moist soils to mimic warm ocean temperatures that fuel a hurricane.

Calling Louisiana's wetlands "land" is a bit of an oversell. It's basically the ocean on a good day, and that's before a high-end category four hurricane covered the region in hot storm surge. As a result, Hurricane Ida remained a major hurricane for nearly 10 hours after landfall. The satellite image above showed the storm with a fully clear eye about four hours after landfall.

It's going to be a while before we get a full picture of just what happened in southeastern Louisiana. Early indications are that "not good" is a solid description of events tonight.

New Orleans is entirely without power after the transmission lines that feed the city fell during the hurricane's high winds. There are reports of significant flooding in some communities nearby from a combination of torrential rains and storm surge.


The system is over solid land now and it's winding down fast. The National Hurricane Center said in its 11:00 p.m. advisory that the storm was now a category two with 105 mph winds. It should be a tropical storm by Monday morning, a depression by Monday night, and "remnants of Ida" by this time on Tuesday.

Even though the system is weakening, it's still a very strong hurricane. Damaging winds will extend far inland. The intensity of the tree damage and power outages may shock people as far inland as Jackson, Mississippi.


Ida's torrential rains will lead to a threat for widespread flash flooding over the next few days. Rainfall totals of 3-5" will be common from Mississippi to Massachusetts and just about everywhere in between. Exact rainfall totals will differ and shift depending on the storm's ultimate track, but it's safe to say that Ida's remnants will bring drenching rains to a large portion of the eastern United States through next week.


A risk for tornadoes will continue on the eastern side of Ida over the next couple of days. The threat is maximized in Louisiana, Mississippi, and Alabama, where small supercells can tap into ample wind shear and produce fast tornadoes.

Tropical tornadoes happen quickly, sometimes reducing tornado warning lead time. Make sure your cell phone's wireless emergency alerts are activated for tornado warnings so you get a warning right away.


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August 28, 2021

Hurricane Ida On Track To Hit Louisiana As A Powerful Hurricane On Sunday


Hurricane Ida is still on track to hit Louisiana as a powerful hurricane on Sunday. The storm is rapidly intensifying in the Gulf of Mexico tonight. The storm has a small eye surrounded by deep convection, a scary look on satellite imagery that often precedes a jump in the storm's strength.

The forecast hasn't changed much today. Hurricane warnings remain in effect for all of southeastern Louisiana as Ida charges a path toward the coastline.

New Orleans is in a very bad spot right now. Any jog to the east in the storm's track will make conditions much worse there.

As I said yesterday, "New Orleans in the eastern eyewall of a major hurricane" is nightmare fuel for meteorologists because of the potential for storm surge and wind damage. (I wrote a post for The Weather Network tonight discussing why Louisiana is so vulnerable to hurricanes.)

The forecasters at NWS New Orleans didn't pull their punches when they wrote tonight's forecast discussion.

Once sustained tropical storm force winds move in first responders will button down and YOU WILL BE ON YOUR OWN. Please understand this, there is the possibility that conditions could be unlivable along the coast for some time and areas around New Orleans and Baton Rouge could be without power for weeks. We have all seen the destruction and pain caused by Harvey, Michael, and Laura. Anticipate devastation on this level and if it doesn't happen then we should all count our blessings.

The details remain the same as the last couple of days. 

Ida will push a tremendous storm surge into portions of southwestern Louisiana, which could top 10 feet in some spots. A dangerous and life-threatening storm surge is possible as far east as the Alabama/Florida border, including Mobile Bay.


Torrential rains in Louisiana will lead to widespread flash flood emergencies. The storm surge and intense winds will hamper rescue efforts. Heavy, flooding rains will fall along Ida's path through the Mid-South and the Mid-Atlantic states. 3-5 inches of rain is a sure bet north through Kentucky, with a couple of inches of rain possible as far east as Washington, Philadelphia, and New York.

Intense wind damage is likely where Ida makes landfall. The NHC keeps using the phrase "potentially catastrophic wind damage" to describe the threat, which is no small thing coming from a very cautious and reserved group of experts. The hurricane's large and growing wind field will extend far to the west and the east of the point of landfall.


Damaging winds are likely well inland, which is why tropical storm warnings stretch deep into central Mississippi. The widespread and potentially long-lasting power outages far inland from the point of landfall will catch many folks by surprise.

A threat for tornadoes will follow the hurricane inland. The greatest threat exists to the east of the storm, covering parts of Louisiana, Mississippi, Alabama, and Florida's Panhandle. Tropical tornadoes happen fast, often reducing lead time. Make sure your phone's wireless emergency alerts are activated and ready to receive tornado warnings.

Hospitals in the south are already overwhelmed by the surge in COVID patients. This hurricane will further strain medical resources and make it harder to treat people who are seriously injured by the storm. The hurricane's flooding and power outages may cause patients on life support to die. (This has happened before during big disasters.)

The storm and response are basically locked in at this point. If you're inland—say, around Jackson, Mississippi—you still have Sunday morning to prepare for power outages and wind damage. Otherwise, it's too close, we're in too deep, and all that's left is to watch and hope it weakens.


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August 27, 2021

Ida Set To Become A Major Hurricane Before Hitting Northern Gulf Coast On Sunday


Hurricane Ida is set to produce destructive winds and life-threatening storm surge when it makes landfall on the northern Gulf Coast on Sunday. The NHC started using intense language—"potentially catastrophic wind damage"—to get the point across that this is an extremely serious storm. This will be a high-impact, memorable event for the southern United States. 

The Storm


Hurricane Ida had maximum sustained winds of 80 mph at the National Hurricane Center's 11:00 p.m. advisory.

The system is much healthier this evening than it was last night, even after crossing Cuba.

It's taking full advantage of warm waters and a favorable environment. Ida's got the look on satellite imagery, with deep convection swirling around the center of the storm, pronounced banding wrapping around its outer edges, and a big and scalloped upper-level outflow indicative of healthy thunderstorms in the storm's core.

The NHC's latest forecast is quite grim. The storm spent Friday evening over the western tip of Cuba. It's since emerged over the southern Gulf of Mexico, and now the hurricane pretty much has a blank check to strengthen as much as it can before it finally makes landfall on the northern Gulf Coast on Sunday.

Waters here are quite warm—upper 80s!—and the storm will face little environmental resistance. The only limiting factor will be any hiccups with its internal structure.


Forecasters are calling for Ida to become a high-end major hurricane before making landfall in southern Louisiana on Sunday. The storm is likely going to make landfall somewhere near Houma, but a dozen miles to the west or to the east will have enormous implications in regards to its wind, surge, and heavy rain.

The storm's track is bad news no matter how things play out.

If Ida trends east, it could put intense winds and a major storm surge into New Orleans. "New Orleans ending up in the eastern eyewall of a major hurricane" is among the top five nightmares that keep meteorologists awake at night.

If the storm trends west or heads into central Louisiana as predicted, the effects of storm surge on populated areas would be lessened, but the marshy coastline would lend little resistance to intense winds slamming into the Lafayette metro area, home to nearly half a million people, and eventually the Baton Rouge area.

That's to say nothing of the flooding rains, the tornadoes, and the widespread power outages—near the point of landfall and well inland—we're likely going to see along Ida's path into the southern states.

Folks in and around the path of the storm need to hurry up and get done what needs doing, because you don't have much time between now and when conditions go downhill this weekend

The Warnings


A hurricane warning (red) is in effect for all of southeastern Louisiana, including New Orleans, Baton Rouge, and Lafayette.

A tropical storm warning (blue) is in effect for southwestern Louisiana, coastal Mississippi, and a portion of southwestern Mississippi.

A hurricane watch (pink) is in effect for counties in Mississippi currently under a tropical storm warning.

A tropical storm watch (yellow) is in effect for Mobile and Baldwin Counties in Alabama, as well as a swath of inland counties in Louisiana and Mississippi, including Jackson.

Notice how deep into Louisiana and Mississippi those watches extend. This system won't wind down immediately after crossing the coastline. We could see widespread inland power outages on top of the potential for flooding rains and tornadoes.

These watches and warnings will probably shift a bit as forecasters refine the storm's track over the next couple of days.

Storm Surge

SOURCE: NHC

We could see a storm surge as high as 10-15 feet above ground level in the hurricane's eastern eyewall. The NHC's surge forecast above is based on storm surge during high tide—if the tide is lower at landfall, then the peak surge would probably be lower as well.

If the storm stays on the NHC's projected track, Ida's worst surge will likely push into relatively unpopulated areas and communities that are built to withstand at least some measure of storm surge.

It's always concerning to see a storm surge pushed into Lake Pontchartrain, southern Mississippi, and southern Alabama. These areas are heavily populated and it doesn't take much surge to flood communities near the coast.

If you know folks in the region, please convince them to heed any evacuation orders. Staying is never worth the risk, either to the people who stay or the people have to rescue or recover them.

Flooding Rain


Freshwater flooding from heavy rainfall will be a significant issue as Ida pushes inland. Widespread double-digit rainfall totals are likely in southeastern Louisiana as the hurricane makes landfall, with 5+ inches of rain falling hundreds of miles inland along Ida's path.

Flash flooding from heavy rain is one of the leading causes of death during landfalling storms in the United States. Never drive through a flooded roadway. It only takes a few inches of moving water to lift up a vehicle and carry it downstream. It's impossible to judge how deep the water is until it's too late, and sometimes the road is washed out beneath the floodwaters.

Winds

Ida will have a large wind field that will extend more than a hundred miles from the eye of the storm. This means that communities pretty far away from the point of landfall could see widespread tree damage and power outages as the storm moves through, even far inland.

The worst wind damage will be where the eastern eyewall comes ashore. The winds of a major hurricane can severely damage or destroy even a well-built home. Wind finds every nook and cranny and leverages that weakness against the entire structure of the house. Usually, garage doors and roofs are the first to go, and the rest of the structure can follow.

If you have trees or tree limbs looming near your house, take them down or trim them now if you can. 

Trees falling into homes are a significant cause of injuries and fatalities during a tropical system.

If you can't trim or chop any trees that could fall into your home, take great care to avoid those rooms during the strongest winds. Make the best of it and have a slumber party in a safe part of the house to lower your risk.

Power Outages

Widespread, long-lasting power outages are likely where Ida makes landfall and for many miles inland along Ida's path.

Every time we have a landfalling hurricane, the extent and severity of inland power outages catches people off guard. 

Here are some tips (which, full disclosure, I've mostly copied and pasted from a post last year) on what you need to do to prepare for an approaching storm:

➤ Food: Don't get caught in a lengthy power outage without any non-perishable food that you don’t have to cook. Fruit cups are good. Ravioli and Spaghetti-Os are good. Milk is no good. Neither is fresh meat. (Spam is great, if that’s your thing.) Have enough to last each person three meals a day for at least a few days. Assume that McDonald's won't have power, either.

➤ Water: Bottled water is fine. Bottle-it-yourself water is better on your wallet and better for the environment. Remember to bottle enough for drinking and to use for flushing the toilet and washing your hands.

➤ Light: You need batteries and flashlights. Not your cell phone’s flashlight feature. An actual flashlight—many, if you can swing it—along with enough batteries for a few refills each. Trust me. Relying on your cell phone’s flashlight feature during a long power outage will just drain your cell phone and leave you without communication or light, and that’s no good.

➤ Cell Phone Charging Packs: Speaking of cell phones, rechargeable battery packs are cheap enough now that they're in reach even on a budget. It's wise to invest in a good battery pack that can give your smartphone at least a few full batteries on a single charge. Even the cheaper ones they often sell near the checkout lane in Walmart are good for a quick battery boost in a pinch.

➤ Gas Up Your Car: Long gas lines are a staple of pre-hurricane coverage on the news, and for good reason. The only thing worse than being stuck at home with no power is being stuck in a powerless home because your car is running on empty. You don't want to get stranded at home (or elsewhere) without any gas. Top off your tank before the storm hits. 

➤ Money: Your debit card and credit card aren’t going to work if the power is out and you need to go to the store and buy stuff. If you can afford a small cushion, having some physical cash on hand can get you through an extended power outage.

➤ Prescription Meds: Keep up with your prescription refills during hurricane season. If you know there’s a storm brewing and one of your prescription refills is coming due, it’s wise to refill it because you don’t know when you’ll be able to get it filled again.

Tornadoes


As always, there's going to be a risk for tornadoes as Ida makes landfall and probably for a couple of days after it starts pushing inland. Tornadoes are most likely on the right side of the system relative to its forward motion, which would be to the east of Ida's track.

The risk above will likely expand beyond Sunday as the hurricane pushes inland.

Tropical tornadoes happen quickly and they can occur with reduced lead time. Make sure you have a way to receive weather warnings the moment they're issued. Take a moment to check your cell phone's wireless emergency alerts and ensure they're activated for tornado warnings.

COVID Safety

Louisiana is at the peak of their worst surge in COVID cases since the pandemic began. SOURCELDH

This is our second hurricane season during the pandemic. We're seeing a huge uptick in cases across the country right now as the Delta variant takes hold. 

This will make it tougher to do things safely, especially when it comes to mass evacuation shelters. If it's feasible, take some time to consider COVID safety in your hurricane plans if you haven't received a vaccination or if you're otherwise immunocompromised.

It's tough to juggle two emergencies at once. But it's necessary. Hospitals are already strained to the limit in many parts of the south, and this storm (and its ensuing effects) will make it that much harder for medical workers to keep up with demand.


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Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.
 

August 26, 2021

New Tropical System 'Could Be Near Major Hurricane Strength' In The Gulf This Weekend


A new tropical depression formed in the Caribbean Sea on Thursday morning. This system is likely going to become Tropical Storm Ida by the end of the day as it heads toward the Gulf of Mexico this weekend.
Forecasters say the storm "could be near major hurricane strength" before hitting the northern Gulf Coast on Sunday. Folks along the northern Gulf Coast have to act fast to prepare for this storm.

The National Hurricane Center has been watching this tropical disturbance for a couple of days now. Models over the last 24-36 hours have zeroed in on a likely landfall along the northern Gulf Coast this weekend.


The NHC's 11:00 a.m. advisory quickly strengthens the new tropical depression into Tropical Storm Ida on Thursday evening, steadily intensifying the storm as it traverses the Caribbean and aims for the tip of Cuba on Friday. The system "could be near major hurricane strength" (direct wording from the NHC) as it approaches the northern Gulf Coast this weekend.

Start Preparing Now

This is going to happen relatively quickly.

We're only 72-84 hours away from landfall. Conditions could start going downhill as early as Saturday night. Start preparing for a storm now, even if you're hundreds of miles inland from the coast. A strong storm can produce strong winds and widespread power outages far inland from the point of landfall.

Only a few barriers will stand in the way of this storm's eventual intensification. The system will encounter plenty of warm water between now and landfall.


Future-Ida's internal structure will be key to how quickly it intensifies. Conditions seem favorable for the storm to coalesce without much of an issue. However, plenty of Atlantic storms seemed poised to explode only to struggle to get their act together. 

Interaction with land is another question mark right now. If the storm makes landfall in Cuba as predicted, friction from the land will disrupt the storm even if only for a little while.

Otherwise, it looks like a straight shot between its current location and the northern Gulf Coast.

It's still too soon to pinpoint an exact landfall location—a shift of a few dozen miles in either direction has huge implications—but the storm's wind, rain, and storm surge will extend far away from the eye of the storm, so this is a concern for anyone in Louisiana, Mississippi, Alabama, and the Florida Panhandle.

The National Hurricane Center will likely issue watches and warnings on Friday and Saturday, which is when we'll get specifics on the wind and storm surge.

The NHC issues forecast updates for the storm every six hours at 4:00 a.m./p.m. and 10:00 a.m/p.m. Central Time, with intermediate strength and position updates every three hours in between.

Flooding


This storm will produce very heavy rain as it pushes inland. The latest forecast from the Weather Prediction Center shows widespread totals of 3-5 inches stretching into Tennessee, with much higher totals near the coast. Rainfall totals and the location of the heaviest rain will shift around as forecasters refine the storm's eventual track and strength.

If you live in a flood zone, this is the time to prepare for flooding and potential evacuations. Think about your daily routes to work/school/wherever and map out alternate ways to get there.

Flash flooding from heavy rain is the leading cause of fatalities during a landfalling tropical cyclone in the United States. It only takes a few inches of moving water to lift a car and send it downstream.

Trees

If you have trees or tree limbs looming near your house, take them down or trim them now if you can. Trees falling into homes are a significant cause of injuries and fatalities during a tropical system. If you can't trim or chop any trees that could fall into your home, take great care to avoid those rooms during the strongest winds. Make the best of it and have a slumber party in a safe part of the house to lower your risk.

Power Outages

Here are some tips (which, full disclosure, I've mostly copied and pasted from a post last year) on what you need to do to prepare for an approaching storm:

➤ Food: Don't get caught in a lengthy power outage without any non-perishable food that you don’t have to cook. Fruit cups are good. Ravioli and Spaghetti-Os are good. Milk is no good. Neither is fresh meat. (Spam is great, if that’s your thing.) Have enough to last each person three meals a day for at least a few days. Assume that McDonald's won't have power, either.

➤ Water: Bottled water is fine. Bottle-it-yourself water is better on your wallet and better for the environment. Remember to bottle enough for drinking and to use for flushing the toilet and washing your hands.

➤ Light: You need batteries and flashlights. Not your cell phone’s flashlight feature. An actual flashlight—many, if you can swing it—along with enough batteries for a few refills each. Trust me. Relying on your cell phone’s flashlight feature during a long power outage will just drain your cell phone and leave you without communication or light, and that’s no good.

➤ Cell Phone Charging Packs: Speaking of cell phones, rechargeable battery packs are cheap enough now that they're in reach even on a budget. It's wise to invest in a good battery pack that can give your smartphone at least a few full batteries on a single charge. Even the cheaper ones they often sell near the checkout lane in Walmart are good for a quick battery boost in a pinch.

➤ Gas Up Your Car: Long gas lines are a staple of pre-hurricane coverage on the news, and for good reason. The only thing worse than being stuck at home with no power is being stuck in a powerless home because your car is running on empty. You don't want to get stranded at home (or elsewhere) without any gas. Top off your tank before the storm hits. 

➤ Money: Your debit card and credit card aren’t going to work if the power is out and you need to go to the store and buy stuff. If you can afford a small cushion, having some physical cash on hand can get you through an extended power outage.

➤ Prescription Meds: Keep up with your prescription refills during hurricane season. If you know there’s a storm brewing and one of your prescription refills is coming due, it’s wise to refill it because you don’t know when you’ll be able to get it filled again.

COVID Safety

This is our second hurricane season during the pandemic. We're seeing a huge uptick in cases across the country right now as the Delta variant takes hold. 

This will make it tougher to do things safely, especially when it comes to mass evacuation shelters. If it's feasible, take some time to consider COVID safety in your hurricane plans if you haven't received a vaccination or if you're otherwise immunocompromised.

It's tough to juggle two emergencies at once. But it's necessary. Hospitals are already strained to the limit in many parts of the south, and this storm (and its ensuing effects) will make it that much harder for medical workers to keep up with demand.


You can follow me on Twitter or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.
 

Prepare Now For A Potential Tropical System In The Gulf This Weekend


A tropical disturbance in the Caribbean Sea has a high chance of developing into a tropical cyclone over the next couple of days as it moves toward the Gulf of Mexico. The system is likely to strengthen in the Gulf as it approaches land late this weekend or early next week. While it's still too early for many specifics, this is the time to prepare and be aware.

The disturbance, dubbed Invest 99L by the National Hurricane Center for tracking purposes, is an open tropical wave in the southern Caribbean Sea. The system isn't much more than a loose collection of scattered thunderstorms over open waters.


The disturbance is moving northwest toward the Yucatan, and conditions should be favorable for the system to develop into a tropical depression or a tropical storm over the next day or two.

Here's what we know (and don't know) right now.

Timing

This is going to unfold relatively quickly. We don't have a week and a half to watch the storm like we would if it traversed the Atlantic. The rapid pace at which this system will likely develop will reduce the amount of time folks along the Gulf Coast and inland will have to prepare.

Right now, it looks like we could see the system approach the U.S. as early as Saturday night or Sunday. 

Strength and Landfall

Right now, it looks like the system will generally head toward the northern Gulf Coast.

It's the end of August, the Gulf is warm, and the atmosphere around the system would be favorable for strengthening, so it's not unreasonable to say it could be a hurricane by the time it approaches the area—if it develops, of course.

The tricky part of tracking tropical disturbances that haven't formed yet is, well...they haven't formed yet. The models are tracking a storm that doesn't yet exist.

But all storms have to start somewhere, and most models are on board with this disturbance getting its act together in a hurry toward the weekend.

Once the system develops—with a structure and a defined center of circulation—models (and forecasters!) will get a better idea of where the storm will go and how much it'll intensify before it gets there.

This storm's name would be either Ida or Julian, depending on whether this develops before or after another disturbance out in the central Atlantic.

Potential Impacts

Strong winds, a dangerous storm surge, widespread flooding from heavy rainfall, and tornadoes would be major hazards along and near the storm's eventual path. It's tough to talk about the specifics until the system actually forms.

Power outages are always a major issue with a landfalling storm, even hundreds of miles inland from the point of landfall. 

Use this time to prepare for a potential storm. As I said last week when Henri first looked like it might head toward the Northeast:

Do you have flashlights and batteries? How about non-perishable food that doesn't need to be cooked? Ravioli is good straight out of the can, especially when the power is out and you're tired of potato chips.

Don't forget all the things we don't think about until we need them, like personal hygiene supplies, medicines, cash if you can afford it (cards don't work if the power's out), and battery backups for your cell phone.

Take a look at what trees loom near your house. If there are any trees or tree limbs that could fall into your home during high winds, take the time to trim them or remove them now. A significant number of injuries and deaths during a tropical cyclone are the result of trees falling into homes.

If you live in a flood zone, make some plans for what you'll do if you have to deal with flash flooding in the next couple of days. Do you have somewhere to go, or an escape plan if you need to evacuate in a hurry?

Keep in mind that we're in the middle of a sharp rise in COVID cases as the Delta variant spreads across the country. Folks who are immunocompromised or otherwise vulnerable to severe illness from COVID might want to consider alternate plans if they consider evacuation shelters too risky.

Check the National Hurricane Center and your local National Weather Service office frequently over the next few days. This is the time to pay attention and prepare. If the storm forms and heads your way, you're ready. If not, then you're ready for the next threat.


You can follow me on Twitter or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.