August 21, 2019

Tropical Storm Chantal Forms Out In The Middle Of Nowhere

A disturbance in the northern Atlantic Ocean developed into Tropical Storm Chantal on Tuesday evening, becoming the third named storm of the unusually quiet-to-this-point Atlantic hurricane season. Forecasters expect the storm to remain far out in the north-central Atlantic, posing a threat to no one but some ships and maybe a floating beach ball or whatever.
An infrared satellite loop of Tropical Storm Chantal on the evening of August 20, 2019 | Tropical Tidbits

The National Hurricane Center began mentioning this disturbance in its tropical weather outlooks last Friday, and it remained at a 10 percent chance of development until the system began to get its act together on Tuesday morning. Hey—a 10 percent chance is still a chance.

The system became Tropical Storm Chantal after developing a sustained patch of thunderstorms this morning, which in turn induced the development of a closed circulation at the surface. Westerly wind shear is keeping the system from looking its best tonight. The storm is moving east at a decent clip and its thunderstorms are all confined to the east of the center of circulation.

This tropical storm is what you stare at when you're a bored weather enthusiast aimlessly wandering around the internet looking for something to do on a late summer weeknight. It's underwhelming, but it's better than watching a King of Queens rerun on TV Land for the 87th time.

Tropical Storm Chantal should remain far out in the central Atlantic Ocean; the 11:00 PM EDT forecast shows the system barely clinging to tropical storm status as it wanders somewhere between Bermuda and The Azores. A cone of uncertainty forms a haphazard blob over the central Atlantic as a result of the storm's expected curly track toward the end of its life cycle—if it survives that long, of course.

Chantal is the first storm we've seen in the Atlantic since Hurricane Barry made landfall on the northern Gulf Coast in the middle of July. That's the longest mid-summer quiet stretch since at least the early 80s. We're approaching peak season and it doesn't take much for one storm to turn into a serious threat if it approaches land. Even though it's quiet and we're talking about one thunderstorm over a semi-naked wind swirl right now, it's wise to make visiting the National Hurricane Center a part of your daily routine for the next month or two. Things can change in a hurry.

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August 15, 2019

GOES-17, The Little Weather Satellite That Could, Survived Another Hiccup Last Night

The United States' newest weather satellite survives to sense another day. GOES-17, known in service as GOES-West, suffered a 10.5-hour outage this morning after a reported software glitch caused the satellite to stop transmitting products and imagery. Engineers were able to fix the problem and the satellite began scanning the skies again this afternoon.

Meteorologists and amateur weather enthusiasts collectively held their breath this morning when NOAA said engineers were looking into a "spacecraft anomaly" that caused an outage of all visible and infrared imagery from the satellite.

The term "spacecraft anomaly" can be one of those coy euphemisms used to describe a particularly bad incident in a way that doesn't sound so upsetting. It's not unlike a chipper flight attendant casually describing what to do in a "water landing," which sounds much more agreeable than "crashing into a lake."

However, and thankfully!, things aren't always as bad as they first seem when an "anomaly" is first spotted. This issue was reportedly a software glitch that engineers solved with a restart of the Advanced Baseline Imager (ABI), the instrument that provides us with visible, infrared, and water vapor imagery.

The satellite is back online and working fine now. The image at the top of this post is a view from the satellite this afternoon. (Ohh. Ahh. Pretty.)

GOES-17 Is No Stranger To Struggle

This isn't the first time the newest GOES satellite acted up. The satellite's ABI encountered a significant failure of its cooling system when engineers booted up the satellite for testing in the spring of 2018. NOAA concluded just two weeks ago that a clogged pipe prevented the ABI's coolant system from working properly.
An example of interference in infrared satellite imagery caused by excess heat given off by the ABI. | NOAA

The problem seemed pretty bad at first—so bad, in fact, that it looked like the satellite would have limited functionality that could hamper its effectiveness.

A geostationary satellite like GOES-17 orbits at the same speed Earth rotates, fixing the satellite over one point on the equator. This fixed position affords the satellite the exact same view of Earth for its entire service life. The altitude required to achieve geostationary orbit also exposes the ABI instrument, which faces Earth, to direct sunshine for several hours a day around the winter and spring equinoxes.

The above picture shows why that's a problem when the cooling system doesn't work properly. The ABI works by sensing 16 different spectral wavelengths (known as "bands") to provide us with the visible, water vapor, and infrared imagery we see in weather reports every day. When the ABI's cooling system fails and it overheats, the heat of the instrument itself begins giving off longwave radiation that matches the wavelengths used to create water vapor and infrared imagery. 

The interference from the overheating instrument leads to noisy, useless satellite imagery across the affected wavelengths for those couple of hours of direct sunshine. Engineers were able to implement fixes and workarounds that brought the satellite up to 97 percent functionality, which is pretty darn good given the bleak outlook just a few months earlier.

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August 9, 2019

The Eye Of A Powerful Typhoon Abruptly Swerved Around This Japanese Island

The eye of Typhoon Lekima made an unusual and impressive curve around Japan's Tarama Island on Thursday evening, preventing the center of the storm from making a direct landfall on the tiny island. The unexpected wobble in the storm's track—which only amounted to a couple of miles—is a testament to how minuscule changes in the track of a storm can have dramatic consequences.

Typhoon Lekima approached Japan's Ryukyu Islands with maximum sustained winds of 130 MPH, making it the equivalent of a category four on the Saffir-Simpson Hurricane Wind Scale. The Ryukyus are the archipelago of tiny islands of between the southern Japanese island of Kyushu and the northern tip of Taiwan.
Infrared satellite view of Typhoon Lekima wobbling around Tarama Island on August 8, 2019. | CIMSS, University of Wisconsin
It looked like the eye of powerful Typhoon Lekima would make landfall when it crossed the archipelago on Thursday night. But just as the typhoon's strongest winds approached Tarama Island, the eye of the storm suddenly changed course.

Over the course of a couple of hours, the typhoon's eye performed a sudden curve around the island and missed landfall altogether. This wobble exposed the island of 1,250 people to the eyewall's intense winds for several hours. While the halting loop of Lekima's eye is unusual compared to other storms, wobbles are common in strong cyclones and these minor track deviations it can make all the difference for those in a storm's path.

Typhoon Lekima's abrupt wobble around Tarama Island is a fantastic example of trochoidal motion within a tropical cyclone. The center of a tropical cyclone doesn't move in a straight line. The paths we see on weather maps are smoothed out over a period of several hours. If you tracked the center of a strong hurricane using each update of a weather radar, you'd get a wiggly line—or a trochoid, hence the name—rather than a pleasantly smooth, computerized line.

Trochoidal motion can occur in the track of a storm's eye for a variety of reasons; in Typhoon Lekima's case, this likely included an eyewall replacement cycle and an uneven distribution of strong thunderstorms within the eyewall itself. Eyewall replacement cycles are common in intense storms as a new eyewall forms around the old eyewall, eventually choking off the old core of the storm and taking over as the storm's dominant feature. The center of the storm can wobble a great deal during this process.

Uneven thunderstorms in the eyewall can also cause a storm's eye to wobble. Strong thunderstorms forming in one part of the eyewall can destabilize the eye of the storm, as these new thunderstorms tug the center of the storm toward them. A fast-changing eyewall can push and pull the center of the storm over a couple of miles in a short period of time, causing wild gyrations like we saw when Lekima approached Tarama Island.

Despite the extended blow from the storm, news reports seem relatively positive despite the storm's size and strength. NHK World reported Friday that the storm caused four minor injuries and power outages to the islands affected by the core of the storm.
Super Typhoon Meranti making landfall on Itbayat Island, Philippines, in September 2016. | CIMSS, University of Wisconsin
Wobbling typhoons can pose a grave threat to the vast expanse of tiny, populated islands of the western Pacific Ocean. These storms are so common—and islands so plentiful—that a handful of these isolated communities take a direct or near-direct hit every year.

Super Typhoon Meranti made landfall on Itbayat Island in the far northern Philippines in September 2016, wobbling just right that the entire island wound up in the eye of the storm for a period of time. Itbayat and nearby islands saw heavy damage from the 2016 super typhoon, but suffered no fatalities as a result of the high construction quality of the buildings there.

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August 1, 2019

A Tropical Depression Is Likely In The Atlantic By Early Next Week

We could see our third named storm of the 2019 Atlantic hurricane season by this time next week. The suspect is a tropical disturbance that's currently about halfway between the Caribbean and Africa. The National Hurricane Center gives the system a high chance of developing into a tropical cyclone as it approaches the Lower Antilles early next week.

The first week of August is when tropical activity in the Atlantic Ocean typically begins to pick up steam. Right on cue, a tropical wave that moved off the western coast of Africa last week is the likely candidate for our next tropical system. The disturbance, currently called Invest 96L for tracking purposes, is rather healthy looking at the moment as far as tropical waves go. The system has plenty of thunderstorm activity and a defined, broad "swirl" in satellite imagery.
Invest 96L on satellite imagery around midnight on August 1, 2019. | Source: GREarth/AllisonHouse
A favorable environment will greet Invest 96L once it moves northeast of the Lesser Antilles next week; as a result, the National Hurricane Center gives the system a 70 percent chance of developing into a tropical depression by early next week.

It's far too early to talk about strength. But the overall pattern in the Atlantic right now does give us an idea of the general track a potential named storm would take. The paths of most tropical cyclones that develop in this part of the Atlantic are driven by the Bermuda High, or the big dome of high pressure that dominates the middle of the Atlantic Ocean in the summer months.

A stronger high tends to push tropical cyclones closer to land, shunting them into the Caribbean or threatening The Bahamas or the U.S. East Coast. A weaker high allows the storm to begin its curve out to sea sooner, posing only a threat to Bermuda and shipping lanes in the northern Atlantic. The strength of this high—as well as a trough that's likely to approach the East Coast late next week—will determine the path of the system (should it develop, of course).

What can you do right now? I'd say "don't worry about it," but I'm a weather-worrier myself. I know how it is, even something like 10 days out. Consider this a great time to make sure all of your preparations are in order even if you're hundreds of miles inland. Take the time to inventory and gather up your supplies, documents, plans—all the stuff we should take care of at the beginning of hurricane season to begin with. If the storm forms and threatens, you're ready. If not, you're ready for the next one.

The National Hurricane Center issues tropical weather outlooks four times a day at 2:00 and 8:00 AM/PM Eastern. The agency won't begin issuing official wind/track forecasts unless the storm actually develops into a tropical depression, which likely wouldn't happen until Sunday at the earliest.

There is another disturbance the NHC has painted on its Wednesday night outlook. The system has a 10 percent chance of developing into a tropical cyclone off the southeastern coast late this weekend or early next week. I left it off of this map because it has such a low chance of developing and the fact that a big highlighted area right next to the U.S. is distracting when we're talking about a different system thousands of miles away.

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July 19, 2019

Hot Nights Will Make This Weekend's Excessive Heat And Humidity Even More Dangerous

Parts of 19 states are under an excessive heat warning over the next couple of days as the combined effect of high heat and stifling humidity climbs to dangerous levels. The heat baking the Midwest this week will grow more intense and spread east toward the Mid-Atlantic and Northeast through the weekend. It's not the worst heat wave we've ever seen, but it'll get hot enough—and stay warm enough at night—that it could take a serious toll on vulnerable populations.

The Heat Index

The above map shows the National Weather Service's heat alerts as of about 9:30 PM on Thursday night. Excessive heat warnings cover a vast area—the widest-reaching heat wave we've seen in a couple of years—including the entire state of Ohio and several of the smaller states on the East Coast, as well as just about every major city between Kansas City and Boston.

These alerts are in place because of the heat index.

Humidity affects us on a hot day because the excess moisture in the air hampers your body's ability to cool itself off. Meteorologists and other scientists worked together to create the heat index to measure the impact that the combination of heat and humidity has on your body.

The heat index isn't made-up for clicks or ratings.

The heat index isn't a scare tactic to make people think the heat is worse than it is.

People who say stuff like that are trying to act cool and hip when they're really just waving their ignorance around for everyone to laugh at.

The heat index is a real metric that tells you what the combined heat and humidity feels like to your body. If it's 93°F with a heat index of 105°F, the moisture in the air is making your body work as hard as it would if the actual air temperature were 105°F. That means heat-related illnesses will set in even faster than you would expect given the air temperature.

Heat alerts are relative to where you live—it's harder to get an excessive heat warning in Wilmington, North Carolina, than it is in Syracuse, New York, because people in the south are used to and equipped for sustained hot and muggy weather. I wrote a post for Outside last summer explaining how each NWS office issues these alerts, complete with a map showing the heat alert criteria for almost every office east of the Rockies.

Here's the National Weather Service's forecast (as of Thursday evening) for the heat index at 5:00 PM EDT on Friday, July 19:

 ...and here's the same forecast for the same time on Saturday, July 20:

...and the maximum heat index forecast for Sunday, July 21, from the Weather Prediction Center:

(Note: The WPC issues maximum heat index forecasts between 3 and 7 days out. I tried to make my own map of their forecasts, but it...uh...didn't turn out well, so I used their map here.)

It's going to feel like the 110s again across much of the Midwest on Friday, with those heat indices moving into the I-95 corridor by Saturday and Sunday. Some models are trying to put Friday's heat index readings into the 120s across the corn fields in places like Iowa. That may be extreme—but not unheard of!—but it underscores just how darn hot and muggy it's going to get.

It won't take long to come down with a heat-related illness in this kind of weather. Folks who work outside or work-out outside are most susceptible to feeling the effects of the daytime grossness. Keep drinking water even when you're not thirsty. You lose liquid faster than you realize when it's hot out.

It's Going To Stay Unbearably Warm At Night

It's bad enough that it'll be dangerously hot and humid during the day, but the temperature at night is extremely concerning in a situation like this. The effect is most pronounced in cities and communities up north where home air conditioning isn't as common as it is down south.

I know folks in the Midwest get salty when we focus on the East Coast when a heat wave affects such a large area, but there are hundreds of thousands of elderly people and folks with health problems in cities like Washington and Baltimore and Philadelphia who will need air conditioning over the next few days but won't have access to it or simply can't afford it.

Those vulnerable populations who can't access air conditioning will be at great risk for illness over the next couple of days if they can't find relief from the heat and humidity. Heat doesn't necessarily kill people because it gets ridiculously gross during the day. A prolonged heat wave kills people because it stays unbearably warm at night, preventing folks who suffer during the day from feeling any relief at night. The stress from the heat compounds day after day until it's too much to take.

Here are the predicted low temperatures on Friday morning:

And Saturday morning:

And Sunday morning:

Some of those temperatures, especially in the Mid-Atlantic and Northeast, are hardly low temperatures at all. 82°F for the low in Washington D.C. and 81°F in New York City on Sunday morning? That's horrendous, and even worse when you account for the humidity that doesn't go away when the sun goes down.

The Heat Will Break Next Week

We're dealing with this heat wave because the jet stream is firmly wedged north of the Canadian border, creating a large ridge of high pressure over the eastern two-thirds of the United States. Ridges of high pressure during the summer are often called "heat domes" because they foster heat waves like the one we're seeing right now.

The ridge will begin to break on Sunday in the middle of the country and by Monday on the East Coast, bringing relief to those who need it the most. It's not going to get cool—hey, it's the middle of July—but we'll go from "dangerously warm" to just "miserably warm," and the latter is at least bearable.

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July 11, 2019

Life-Threatening Flooding Likely As Tropical Storm Barry Crawls Toward Louisiana

Extremely heavy rain associated with Tropical Storm Barry will lead to life-threatening flooding across southern Louisiana and the lower Mississippi River Valley over the next couple of days. The slow-moving storm could reach hurricane strength before it makes landfall on the Louisiana coast on Saturday. Latest forecasts show double-digit rainfall totals across the eastern part of the state, compounding ongoing flooding issues across the region.

NHC Forecast

The disturbance we've been watching for the last couple of days developed a closed surface circulation on Thursday morning, allowing the National Hurricane Center to upgrade the system to Tropical Storm Barry. The NHC's 7:00 PM CDT advisory shows the storm slowly organizing over the next two days, possibly strengthening into a hurricane before making landfall in southern Louisiana on Saturday morning.

Conditions across the northern Gulf of Mexico are conducive to strengthening if the storm can get its act together fast enough to take advantage of its environment. Barry's structure on Thursday afternoon was...lacking...with an exposed low-level circulation south of the mouth of the Mississippi River, and almost all clouds and convection fanned-out on the southern side of the system.

The window for strengthening will begin to close the longer the storm remains disorganized. That's great news in terms of wind and storm surge, but Barry is set to bring flooding rains to the northern Gulf Coast regardless of its strength at landfall.

Rainfall Forecast

While wind speeds and the phrase "hurricane warning" will get the most attention, the real story of this storm is the water. Barry threatens to wring out a tremendous amount of tropical moisture over the northern Gulf Coast through this weekend.

The latest rainfall prediction from NOAA's Weather Prediction Center shows the potential for 20" or more—yes, that's twenty inches or more—of rain across southern Louisiana. A wider swath of half a foot or more of rain spreads up the Mississippi River toward the Memphis area.

Not everyone will see all of the rain in the forecast. But the storm will move slow enough that rain bands and thunderstorms will be able to tap into a deep reserve of tropical moisture and produce copious amounts of rain in a short period of time.

It's important to note that these predicted rainfall amounts will change as the storm gets closer to land and forecasters get a better handle on the structure and future track of the storm. Small changes in intensity, organization, and track will shift the bullseye for heavy rain with time. The overall point is that everyone in Louisiana should prepare for a potentially significant flooding event.

Flooding Potential

The combination of accumulated water from heavy rain, the Mississippi River rising from excess upstream runoff, and a potential storm surge could severely strain the ability of New Orleans and surrounding areas to stave off floodwaters.

The Mississippi River is already in flood from months of heavy rain across the central United States. Add that on to the flash flood emergency that played out across New Orleans on Wednesday—dropping more than half a foot of rain in a couple of hours—and it won't take much heavy rain to cause major flooding along the area's already-strained waterways.

River flooding forecasts from the National Weather Service show the Mississippi River in New Orleans cresting at 19 feet if current precipitation forecasts hold up, which would be the highest crest recorded there since February 1950. The levees along the Mississippi in New Orleans are only 20 feet tall, so the water would only be about a foot away from the top.

The entire city of New Orleans sits below sea level. Not only does it face a threat from the bodies of water that surround the city, but rainwater has to be pumped out of the city because it can't seep into the ground. The pumps can handle rainfall rates of 1.00" in the first hour and 0.50" in every subsequent hour after the rain stops. Rain that falls faster than that will cause flooding in spots around the city until the pumps can catch up with the excess water.

It's not just New Orleans, either. The excessive rainfall amounts forecast across Louisiana and throughout the lower Mississippi River Valley will cause extensive and life-threatening flash flooding across the region.

A scenario like this played out not too long ago. A disturbance over the northern Gulf of Mexico brought a widespread swath of 10"-20" of rain to central and eastern Louisiana back in the summer of 2016. The resulting flooding was some of the worst in Louisiana's modern history, killing more than a dozen people and causing more than $10 billion in damage. Many homes destroyed by the floods in 2016 didn't have flood insurance, as the owners thought they were safe from flooding.


Flooding is the greatest threat, but we can't ignore the winds. Hurricane warnings are in effect for the central Louisiana coast for the potential that Barry could strengthen into a hurricane before reaching land. In practical terms, though, the difference between a 70 MPH tropical storm and a 75 MPH hurricane is negligible.

Wind gusts above 70 MPH and soggy ground will allow trees and power lines to fall with relative ease. Widespread power outages are likely where the strongest part of the storm makes landfall. Strong winds will easily snap tree limbs and blow around small debris—stuff like trash cans and yard decorations.


Tornadoes are always a threat in the right-front quadrant of any landfalling tropical system. Folks along and to the east of Tropical Storm Barry's track will stand the greatest threat for tornadoes. Tropical tornadoes are different from tornadoes you'd see in a "regular" thunderstorm. They can happen so quickly that forecasters can miss them between radar sweeps. Eastern Louisiana, Mississippi, and Alabama will have to be on the lookout for tornadoes as the storm makes its way inland.

[Satellite Image: NOAA]

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July 9, 2019

Tropical System In Gulf Likely To Strengthen; Greatest Threat Is Flooding From Heavy Rain

A tropical disturbance entering the Gulf of Mexico has a high chance of growing into a named storm by the end of the week. Some models have the system intensifying before it makes landfall on the northern Gulf Coast this weekend. Flash flooding from heavy rain is far and away the greatest threat with this system, no matter what it's called at landfall.

Tuesday afternoon's update from the National Hurricane Center gave the disturbance, dubbed "Invest 92L" for now, an 80 percent chance of developing into a tropical depression by Thursday morning. We've been watching this trough of low pressure mosey southward across the southeastern United States for a couple of days. The disturbance emerged in the northeastern Gulf of Mexico on Tuesday morning, opening the window for potential development over the next day or two.

Conditions over the Gulf of Mexico are capable of supporting a tropical system. Sea surface temperatures in the northern Gulf are in the mid- to upper-80s, which is plenty warm enough to support tropical development. Low wind shear will allow thunderstorms to develop without getting ripped apart, and ample moisture should stave off intrusions of dry air from suffocating the storm.

The major complication here is the structure of the disturbance itself. It's pretty disorganized at the moment. Assuming the system develops, exactly where it takes root and how strong it gets will ultimately determine how far west it travels across the northern Gulf. A stronger storm may be able to tap into winds that could steer the storm farther west across the Gulf.

Water is the greatest threat with this system no matter what it does. The best case scenario right now is that this system remains disorganized and weak. The worst case scenario is that the system gets its act together in a hurry, posing a threat for wind damage and power outages in addition to lots of heavy rain.

Either scenario would bring heavy rain to the Gulf Coast. The latest forecast from the Weather Prediction Center shows more than five inches of rain falling across a wide swath of the southern United States, with a maximum near the coast where the system ultimately makes landfall. This swath of heavy rain will shift in location and intensity as forecasters get a better handle on exactly what will happen. Everyone along and inland of the Gulf Coast is at risk of seeing flooding rains through next weekend.

We've seen so many storms in recent years—from tropical storms to major hurricanes—leave behind horrendous flooding in their wake. Folks in Texas and North Carolina are intimately aware of the threat for flooding in a landfalling tropical system. Even so, it's still a major battle to get folks in harm's way to appreciate the threat of water over the threat of wind.

The threat of winds can't be completely ignored, of course. Strong winds could cause damage if this system reaches shore as a tropical storm or hurricane. Tree damage, power outages, and some structural damage would be possible in that scenario. Those are significant hazards, made even worse by the potential for flooding from heavy rains.

Forecasters (and weather models!) will have a better idea of what's going to happen over the next couple of days once—and if—the system develops and there's actually something there to analyze. It's a good idea to prepare for an extended period of heavy rain if you live in any of the southern states. Good questions to ask yourself right now include "do I have multiple routes to get around if roads are flooded out?" and "do I have food and supplies to get through a couple of days without power?"

The National Hurricane Center will begin issuing advisories on this system every 3-6 hours if/once it develops into a tropical depression. In the meantime, they issue tropical weather outlooks every six hours at 2:00 and 8:00 AM/PM Eastern Time.

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July 7, 2019

A Trough Over Georgia Could Become A Tropical System In The Gulf—And It's Not As Weird As It Sounds!

The National Hurricane Center is monitoring a trough of low pressure over the southeastern U.S. for signs of tropical development once it reaches the Gulf of Mexico in a couple of days. A disturbance turning into a tropical cyclone once it moves from land to sea isn't as weird as folks are making it sound on Facebook and Twitter—after all, where do you think Cape Verde hurricanes come from? (It ain't the stork!)

Sunday's 8:00 PM EDT update from the NHC gives the disturbance over northern Georgia a 60 percent chance of developing into a tropical system once it reaches the northern Gulf of Mexico later this week. Conditions are favorable for the system to slowly organize by late next week as it meanders in the northern Gulf.

Even if the storm doesn't develop, it looks like a good bit of rain will fall along the northern Gulf Coast and points inland once this whatever-it-is starts moving inland next weekend. The latest rainfall forecast from the Weather Prediction Center shows a boatload of rain (technical term!) falling across parts of Florida, Alabama, and Georgia, through next Sunday, and these totals could easily tick higher if the system organizes and grows stronger once it reaches the Gulf. Flash flooding is likely in areas that see too much rain too quickly.

Everything I've seen about this system on social media so far makes a hullabaloo about the National Hurricane Center mentioning it in their outlooks while the trough was still over Tennessee. If that seems weird, it shouldn't. Lots of tropical systems begin as clusters of storms that form over land and move over the ocean.

You know how we talk about Cape Verde hurricanes and "tropical waves" moving off of Africa in August and September? Those are disturbances that begin over western Africa and move over Atlantic Ocean. Most of the big hurricanes we remember—Katrina! Andrew! Rita! Charley!—started as troughs or thunderstorms over the African continent.

Most folks just aren't used to hearing about this process occurring over the United States. Well, that, and the fact that it's a little unsettling to see a giant X over Tennessee on a map produced by the National Hurricane Center. But this is certainly one method of tropical development this early in the season, and the Gulf of Mexico is a prime location for storms to develop in July.

Oh, and if you're wondering..."Barry" is the next name on this year's list of tropical cyclone names for the Atlantic Ocean. (We used the name Andrea back in May.)

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