August 29, 2018

Warnings of Extreme Heat Aren't a Matter of Wimpiness—It's All About What You're Used To

The true great American pastime is putting down people from other parts of the country. Those southerners eat so unhealthily. Northerners are so rude. People in California are so snobby. These rivalries thrive when it comes to the weather. Summertime heat brings out the worst of our mockery. “Why do those northerners need a heat advisory for temperatures cooler than our normal high?” For once, the answer to that question doesn't boil down to “because they're wimps.” There really is a difference between the north and south when it comes to extreme heat or cold.

The National Weather Service issues dozens of watches, advisories, and warnings to alert us to hazardous weather and help us make decisions to keep ourselves safe. The alerts range from the mundane—something like a fog advisory—to the most urgent tornado warnings.

Some of these alerts are the same all around the country and some vary from county to county. Alerts like tornado warnings and severe thunderstorm warnings are static. A severe thunderstorm warning is issued for a thunderstorm capable of producing hail the size of quarters or larger and/or 60 MPH wind gusts. It's the same whether you're in Seattle, Washington, or Mobile, Alabama.

Then there are relative alerts. A winter weather advisory is a relative alert. It only takes a dusting of snow in Pensacola, Florida, to trigger a winter weather advisory, but it takes 4 inches of snow in 12 hours to meet the criteria for a winter weather advisory in Cleveland, Ohio.

Extreme cold and extreme heat are relative because it's all about what you're used to. We're all acclimated to different temperatures. It's easier for someone in North Carolina to suffer through three months of heat and humidity than it is for someone in Atlantic Canada to deal with it for a few days. 'Stifling' is the default setting somewhere like Tampa for much of the year. If places like Louisiana or Texas followed the same heat advisory guidelines as Michigan or Vermont, they'd be under a heat advisory all day and all night for months on end. It would be meaningless.

A heat advisory is issued when an expected period of hot temperatures—either air temperature or heat index—could pose a risk to those who are sick, elderly, or working outside for an extended period of time. An excessive heat warning is issued when dangerously hot temperatures are in the forecast that could quickly cause heat-related illnesses to set in for even healthy individuals.

The heat index is the temperature it feels like to your body when you take into account the amount of moisture in the air. Your body cools off less effectively when there's more moisture in the air, making it feel much hotter—and allowing heat illness to set in more quickly—when it's more humid.

I did my very best to map out the heat index required for a heat advisory for areas east of the Rocky Mountains. The criteria for a heat advisory is different across the country. It's pretty hard to map out the exact criteria because it's subjective for some offices and the temperatures needed can change quickly across short distancse.

Many NWS offices—especially in the south and east—have their criteria helpfully laid out in various places online (see here, here, and here). Some of the heat index requirements on the above map are inferred based on the text of past heat advisories and the requirements of the surrounding offices. My piecemeal map works as a good illustration for these purposes.

It only takes a heat index of 95°F or higher for a heat advisory to be issued in much of New England. The heat index (or air temperature) required for a heat advisory slowly rises the farther south you go. The criteria reaches 108°F along the Gulf Coast and 110°F in desert areas of the southern Plains. (The 110°F requirement in parts of South Carolina and Georgia is due to these areas routinely seeing some of the hottest and muggiest days along the East Coast.)

The heat index routinely climbs above 100°F during the summer months in Miami. Using New England's criteria, a heat advisory would be issued for Miami almost every day for months on end. But residents of the city are acclimated to the heat. Even vulnerable populations—such as the elderly and outdoor workers—mostly know how to handle the heat in a way that doesn't make them sick.

On the other hand, wind chills dipping into the lower 30s is all it takes for a wind chill advisory in Miami. It takes a wind chill of -15°F and -24°F for at least three hours for NWS Boston to issue a wind chill advisory. It's all a matter of what you're used to.

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August 28, 2018

The United States' New Weather Satellite Isn't Quite as Broken as We Thought

Are you ready for some preliminary, non-operational good news? Sure you are! It's about time we had something positive. GOES-17, the shiny new satellite the United States launched into orbit a couple of months ago, isn't quite as broken as we thought it was when they fired it up earlier this year. Not only has the latest weather satellite's future been upgraded from "oh no, please no" to "working (for the most part)," but today we're starting to get our first public images from the satellite.

GOES, short for Geostationary Operational Environmental Satellite, is the United States' advanced network of weather satellites that keep a constant eye on storms across the Western Hemisphere. The family of satellites has seen numerous series since the first launch in 1975. GOES-17 is the second satellite in the fifth GOES series; the first, GOES-16, went into operation as GOES-East in late 2017. GOES-17 is slated to become GOES-West, covering the western half of the Western Hemisphere, when it's put into operational use later this year.

GOES-17 launched from Cape Canaveral back on March 1 and quickly wiggled its way into a testing orbit in the following weeks. Once scientists started firing up the satellite's instruments, they found that the cooling system for the Advanced Baseline Imager (ABI) isn't working at full capacity.

The ABI is the instrument that gives us all of our visible, infrared, and water vapor imagery. The ABI analyzes radiation from the Earth at 16 different wavelengths (known as "bands") to give us everything from visible imagery—showing us clouds as if we took a picture with a camera—to water vapor imagery that shows the location of moist and dry air at different levels of the atmosphere.

Visible imagery utilizes the shortest wavelengths, while infrared imagery—the colorful images that tell us the temperature of the cloudtops and allow us to see clouds at night—operates at the longest wavelengths.

An example of degraded infrared imagery from the GOES-17 satellite, August 14, 2018. | Source: NOAA/NASA

When the ABI runs hotter than it's designed to handle, the instrument starts giving off enough heat that the additional radiation effectively drowns out some of the infrared products that run on longer wavelengths. The above image from NOAA shows what the interference will look like when excess heat starts interfering with certain water vapor and infrared products. The image is unusable for anything but wall art.

Not all hope is lost, though. Scientists working on the satellite have determined that they can change up the position the satellite so that the longer-wavelength products will only be unusable for just a few hours a day during certain parts of the year.

All 16 channels should be available around the clock near the solstices, while the usability of longer-wave products like water vapor and most infrared imagery will be unavailable for a couple of hours at night around the vernal and autumnal equinox.

Why the equinoxes? GOES-17 follows a geostationary orbit above the equator; by matching its orbital speed to the rotation of the Earth, the satellite always stays over the same spot and always has the same view of the planet. This orbit exposes the satellite to the most intense solar radiation when the sun's energy is focused on the equator around the vernal and autumnal equinox, and the least-direct radiation when the energy is focused on the Tropics of Cancer and Capricorn on the solstices.

The greatest heating will occur at night because of the satellite's distance from the Earth. The front-facing ABI will experience direct sunlight while it's nighttime in the Americas, while the instrument will be shielded from direct light when the satellite has its back to the sun during the Americas' daytime.

GOES-17 red band visible imagery, 5:00 PM EDT August 28, 2018. Source: RAMMB/CIRA
While it's great that we'll have full use of the new satellite between 75% and 85% of the time, that's still going to amount to tens of thousands of hours of product downtime for meteorologists trying to track storms and features in great detail. NOAA says that they're going to fill in the coverage gaps by using GOES-17 alongside the less-advanced (but fully-functioning) GOES-15, which currently serves as GOES-West.

All images and products from GOES-17 are considered preliminary and non-operational until NOAA says otherwise. (I have to put this in here or I might get an angry email from someone with a dot-gov email address.)

That being said, you can get some of those preliminary and non-operational images from the awesome SLIDER tool by RAMMB/CIRA, the source for the image at the top of this post. The full suite of products aren't available yet, but the data we do have is pretty nice (and such a relief) to see.

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August 22, 2018

Hurricane Lane Poses the Greatest Storm Threat to Hawaii in a Generation

Hurricane Lane is on course to pose the greatest tropical threat to Hawaii since Hurricane Iniki made landfall on Kauai nearly 26 years ago. While the powerful category four storm is not currently forecast to make a direct landfall on any of the main islands, the hurricane's wide-reaching effects will still touch all seven populated islands later this week.

The storm reached its peak strength on Monday night, achieving category five intensity with 160 MPH winds, a rare feat for storms in this part of the Pacific Ocean. Hurricane Lane has since weakened a bit and it will continue to lose strength over the next couple of days. However, "weakening" is a relative term, and Lane will still be a strong hurricane when it comes perilously close the state on Thursday, Friday, and Saturday.

Dangerous Even Without Landfall

The latest forecast from the Central Pacific Hurricane Center in Honolulu shows that Lane is a high-end category four hurricane with maximum winds of 150 MPH. The storm has started to gain latitude, moving on a west-northwesterly course toward Hawaii. The current forecast shows Lane scraping all seven populated islands as a hurricane between Thursday and Saturday before it makes its way west toward open sea.

Hurricane Lane will be dangerous even if its eye never makes landfall. The path of the storm on the forecast map above only applies to the eye of the hurricane. The dangerous effects of the storm—strong winds, heavy rain, storm surge, rough surf, and tornadoes—will extend hundreds of miles away from the eye.

Even on an offshore track, it's increasingly likely that the entire state of Hawaii will experience a period of hazardous weather conditions.

Tropical storm force winds currently extend 140 miles from the center of the storm. It wouldn't take much of an eastward wobble in the storm's track to bring hurricane force winds onshore. In fact, the latest CPHC forecast shows hurricane force winds reaching the heavily-populated southern shore of Oahu, home to Honolulu.

A storm surge greater than three feet is possible on south- and west-facing shores, especially on the Big Island and Oahu. This could cause major coastal flooding in and around Honolulu and Pearl Harbor. Flash flooding will be a major concern with this hurricane. The entire island chain could see more than 10 inches of rain with more than a foot likely around higher terrain where orographic lift enhances rainfall rates. The heavy rain will also trigger mudslides and rockslides in mountainous areas. High surf and rip currents will pose a significant danger to swimmers, boaters, and communities along the immediate coast.

Lane Isn't Iselle

One of the issues we run into when we talk about storms threatening the contiguous United States is that a decent portion of coastal residents just don't want to take tropical threats seriously. This is a big problem in a state like Florida, where, despite the extended hurricane drought between 2007 and 2017, residents feel like they have the experience and moxie ride out any storm below a certain category on the Saffir-Simpson Scale.

Hopefully this issue of comparative complacency won't be too much of a factor in Hawaii. The island chain hasn't been directly affected by as many hurricanes as you'd think given its location.

Surprising as it is, Hawaii really hasn't had to deal with many hurricanes in its modern history. The state has had many glancing blows with tropical cyclones in recent decades, but few full-fledged hurricanes have come as close as the forecast track for Hurricane Lane. The last major hurricane to affect the state was Hurricane Iniki in September 1992. The category four hurricane , which made landfall with little advanced warning, left behind significant damage on Kauai.

The closest analogy in recent times was Hurricane Iselle, which made landfall as a tropical storm on the eastern shore of the Big Island in August 2014. The storm's path took the center of circulation directly over the island's 13,000-foot volcanoes, shredding the system apart before it could bring serious effects to any other islands.

Unfortunately, Lane is not similar to Iselle. This hurricane will be considerably stronger than Iselle at its closest approach and it's approaching the islands on a curving path from the south, which will spread its effects over all of the islands in the coming days.

This looks like it will be a storm unlike anything Hawaii has faced in decades.

The Preparation Problem

Hawaii is cemented in the American worldview as the mainland's vacation destination. Everyone dreams of going to Hawaii to spent a week or two without a care in the world. The state is home to more than a million people, however, and they really don't have many options to escape the worst of a hurricane.

Hawaii's infrastructure outside of major cities is not as well-built as many hurricane-prone areas of the contiguous United States. Homes, roads, and electrical grids may not fare as well against a hurricane's wind and rain as we would see on the mainland.

Tourists can also pose a unique safety issue during a hurricane. Most tourists will leave a vacation destination ahead of a storm, but a lot of folks—especially in an expensive and hard-to-leave vacation spot like Hawaii—decide to ride it out and hope for the best.

A hurricane approaching an island chain is different from a hurricane approaching a continent. You can't really evacuate from the storm unless you catch one of the last flights out before airlines start cancelling departures. When you're on an island, you can only evacuate to relatively safer spots—sturdy buildings that are away from flooding and mudslide dangers.

For many tourists, this means staying in the hotel for several rainy, possibly-powerless days at a time. No beach. No restaurants. No Instagram selfies on cliffs. Just staying put and staying occupied. Some people won't want to do that, and every tourist who tries to go all Reed Timmer and venture into the storm makes it that much harder for rescue and aid to reach the endangered residents who—let's not put it gently—actually belong there.

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August 21, 2018

How Thunderstorms Near Madison, Wisconsin, Produced a Foot of Rain in a Few Hours

A significant flash flood event unfolded just west of Madison, Wisconsin, on Monday evening, after thunderstorms dropped more than a foot of rain in just a couple of hours. The resulting flash floods inundated streets and neighborhoods, washing away cars and killing at least one person. The record-breaking rainfall unfolded after all the right ingredients came together over an extremely small area.

The National Weather Service's precipitation analysis for Monday, August 20th, showed a bullseye of heavy rain over a tiny part of west-central Dane County, Wisconsin, just west of the state capital of Madison. There was a sharp gradient between a rainy afternoon and a flooding emergency. The greatest totals were measured in Middleton, where some gauges recorded more than a foot of rain in just a few hours.

Monday's rainfall event was unprecedented in this area. The most rain ever recorded in 24 hours in Wisconsin was 11.72" in Mellen, Wisconsin, back in 1946. The heavy rain near Madison will become the heaviest rain ever recorded in 24 hours in Wisconsin if meteorologists verify reports of more than a foot of rainfall.

There aren't many natural or man-made waterways in the world that can handle that much rain all at once. The effect of the heavy rain and flooding is readily apparent on webcams operated by the USGS. The above video, taken by the USGS at Pheasant Branch in Middleton, Wisconsin, shows how quickly the water rose with the rain on Monday. The time lapse video starts at 7:00 AM on Thursday and runs through noon on Tuesday.

The thunderstorms that triggered the flash flooding near Madison were associated with a low-pressure system over the Mississippi Valley. The lines of storms produced damaging winds and even a couple of tornadoes from southern Wisconsin through Louisiana.

Dane County's deluge started when individual cells began training over the Madison area in the early afternoon hours on Monday. A particularly heavy thunderstorm reached Madison's western suburbs just as a line of thunderstorms approached from the south; the interplay between the existing heavy rain, the approaching line of storms, low-level winds converging near Madison, and a small mesoscale convective vortex all allowed the thunderstorms to sit and pivot over Dane County for several hours, prolonging the heavy rain which led to the flash flood emergency

The storms over south-central Wisconsin formed in just the right environment to wring out every drop of tropical moisture from the atmosphere. The low-pressure system responsible for all the active weather dragged deep tropical moisture north into Wisconsin on Monday.
Source: Pivotal Weather
You can measure the amount of moisture in the atmosphere by looking at precipitable water (PWAT), which measures how much rain would fall if all the moisture in a column of the atmosphere were condensed and fell as rain. PWAT values for southern Wisconsin on Monday evening were greater than 1.50", which is indicative of a moist, tropical atmosphere. These high PWAT values allowed the thunderstorms to tap into a deep reservoir of moisture and produce copious amounts of rain in a short period of time.

It's hard to predict these kind of localized events ahead of time. NWS Milwaukee did issue a flash flood watch for southern Wisconsin ahead of Monday's heavy rain. Meteorologists knew ahead of time that the setup would allow for the potential for flash flooding, but there was no way to know in advance just how bad the rain would be. This is why it's so important to listen for warnings even when you're not expecting the very worst from the storms that day. The atmosphere is complicated and it doesn't take much for regular thunderstorms to quickly turn into a big issue.

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August 20, 2018

Hurricane Lane May Pose a Threat to the Hawaiian Islands Later This Week

Hurricane Lane is a powerful category four storm this afternoon as it slowly makes its way in the direction of Hawaii. The storm is forecast to take a path that brings it uncomfortably close to the Hawaiian Islands later this week, though exactly how close—and its impacts—are still to be determined given the complicated setup driving the hurricane's future path.
Several aircraft investigated Hurricane Lane this afternoon and found that the storm had maximum sustained winds of 130 MPH and a minimum central pressure of 964 mb. This makes Lane a category four hurricane on the Saffir-Simpson Hurricane Wind Scale, the second such storm in this part of the world in the past week. Hurricane Hector passed through the same area last week as a stronger storm. 

The latest forecast from the Central Pacific Hurricane Center—the NHC's sister agency in Honolulu—shows Lane turning toward the northwest around the middle of the week. While the storm will start to lose strength as it encounters wind shear closer to the islands, it will still be a strong storm as it comes dangerously close to the 50th state.

All seven populated islands are within the cone of uncertainty, which is the historical margin of error in previous hurricane track forecasts. The cone of uncertainty only applies to the eye of the storm, however, and Hurricane Lane's effects will extend hundreds of miles from the center of the storm. Even if the storm's eye misses Hawaii to the south, significant impacts can't be ruled out, especially on the Big Island, Maui, Lanai, and Molokai.

On the storm's current path and timing, watches and warnings will likely be required for the Big Island within the next day. The latest CPHC forecast says that Wednesday morning is the earliest reasonable arrival time for tropical storm force winds if they affect the Big Island, with the successive islands feeling the first effects over the following day.

Lane is in an environment that makes it hard for forecasters and weather models to agree on what will happen. The storm's future path will be determined by the strength of two ridges of high pressure—one to the southeast of the hurricane and one to the east. The interplay between the two ridges will dictate how soon and how sharply Lane curves north/northwest as it approaches the islands.

Just like their counterparts at the National Hurricane center, the Central Pacific Hurricane Center in Honolulu will issue updates on Hurricane Lane every six hours—at 11 and 5 AM/PM—with intermediate updates every three hours in between once watches and warnings are in effect. Hawaii is six hours behind Eastern Daylight Time.

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Benevolent Low-Pressure System Set to Bring Sweet, Merciful Taste of Fall

A brief hint of fall will wash over parts of the central and eastern United States over the next couple of days as a low-pressure system forces Canada to share some of that sweet autumn air with its less-deserving neighbors. Dry air will allow temperatures to bottom out in the 50s in some spots through the end of the week. It won't last very long, but it's a nice break from the humidity and a reminder that the end of summer is near.


The first preview of fall is the appearance of strong thunderstorms that are likely today in parts of the south and Midwest along and ahead of the cold front along the Mississippi River and the warm front farther north. A secondary peak in severe weather season typically starts during the fall as strong low-pressure systems sweep across the country.

An enhanced risk for severe thunderstorms—a three on a scale from one to five—exists across the Mississippi Valley from southern Illinois south through Memphis. The greatest threat with today's thunderstorms is damaging winds, though some tornadoes and instances of large hail can't be ruled out, especially in the areas under an enhanced or slight risk.

The marginal risk for severe weather over North Carolina today is due to potential for damaging winds from some of the thunderstorms that develop.

Dry Air

Source: Tropical Tidbits
The low-pressure system responsible for today's thunderstorms will slowly move northeast over the next couple of days, allowing drier, cooler air from Canada to fill in behind it. It's going to feel fantastic in areas that benefit from the lower humidity, and that's really all you can ask for when it's still August. Low humidity even makes highs in the mid- to upper-80s feel comfortable.

The dew point is the best way to measure the comfort of the moisture in the air. Relative humidity is, well, relative, so it constantly changes as the temperature changes. The dew point means the same thing no matter what, so it's a good way to index our comfort or misery. Generally, dew point values below 60°F are comfortable, and it's oppressively muggy when the dew point climbs above 70°F.

You can follow the progression of dry air with the above loop of dew point values from last night's run of the GFS model, shown above. The loop runs through next Monday, August 27th.

The reprieve won't last very long—two or three days at most in the luckiest areas near the Great Lakes—but just a break from the monotonous slop of summer air is all it takes to refresh you long enough to wait for sustained autumn air to start taking hold.


Source: Climate Prediction Center
Things will start to cool down in the coming weeks, but probably not as quickly as we'd like. The Climate Prediction Center's latest outlook for the autumn months calls for decent odds of above-average temperatures for just about the entire Untied States. That doesn't mean we'll be sweating like crazy through Halloween—though, the way things are going these days, I wouldn't count it out, either—but it probably won't get crispy-cool right away.

While above-average temperatures is mostly a matter of personal comfort east of the Rockies, it's a serious issue out west. The western United States has been dealing with above-average temperatures for quite a while now, and each day that passes with warmer-than-usual temperatures and no rainfall adds to the fire danger. The Mendocino Complex, the largest wildfire in California's recorded history, is still burning nearly a month after it started, joining fires raging in western Canada to blanket North America and the Atlantic Ocean in thick smoke.

[Satellite Image: NOAA]

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August 15, 2018

Another Weak Storm Forms in Oceanic Boondocks As Peak of Hurricane Season Nears

Subtropical Storm Ernesto formed in the northern Atlantic Ocean on Wednesday, posing a threat to nothing but some fish and ships. The cyclone may strengthen a tiny bit over the next day or two as it accelerates northeast toward a less favorable environment. The Atlantic hurricane season has been rather anemic this year, puffing out storms that look more like Ernesto than anything more serious. (Not that there's anything wrong with that.) But don't let the quietness fool you—we're on the doorstep of peak season, and history says there's a good chance we'll see a decent storm or two in the next few weeks.

The National Hurricane Center says that Subtropical Storm Ernesto has 40 MPH winds as it lingers many hundreds of miles from anyone who cares. The system is...sufficiently spinny?...on satellite imagery. It's hard to find anything complimentary to say about a sad storm like this. One interesting sight is that you can actually see smoke from the California wildfires wrapping into the storm from the north. (Yes, really.) The storm will continue in the general direction of the Ireland and the United Kingdom as it degenerates and merges into a frontal system this weekend.

Ernesto is a subtropical storm. The difference between subtropical and tropical is an academic exercise that does more to confuse people than serve a practical purpose. A tropical cyclone is a low-pressure system that has a tightly-packed core of thunderstorms around its center of circulation. A tropical cyclone has warm air through the entire storm—top to bottom, side to side—and the storm gathers its energy through the thunderstorms at the core of the storm.

A subtropical cyclone, on the other hand, is one that features characteristics of both a tropical cyclone and an extratropical cyclone, or the typical low-pressure system you'd see over land. A subtropical cyclone isn't uniformly warm throughout the entire storm. A subtropical cyclone's thunderstorms and winds can be far removed from the center of circulation. A subtropical cyclone usually gathers some of its energy from upper-level winds rather than through thunderstorm activity.

Subtropical cyclones are kind of tropical, and their impacts are similar enough to tropical systems that the NHC gives them the same treatment.

So far this year, four out of the five storms we've seen in the Atlantic Ocean were subtropical at one point during their life cycles. It's a testament to the unfavorable conditions that have dominated the ocean basin for the past couple of months.

The end of May saw Alberto make landfall in Florida as a subtropical storm. The unlikely life of Hurricane Beryl swiftly ended as it approached the Lesser Antilles, only to redevelop as a subtropical storm almost a week later. And Debby formed in roughly the same spot as today's Ernesto, starting life as a subtropical storm before transitioning into a fully-tropical storm with 50 MPH winds.

We'll have to keep a very close eye on the tropics over the next month. While unfavorable conditions for tropical development—high wind shear, dry air, Saharan dust—will continue for the foreseeable future, we're in prime season for tropical waves coming off of Africa's west coast to develop into something more. The NHC's evening forecast on Wednesday called for a small window of opportunity for a bulky tropical wave moving toward the Lesser Antilles to develop a bit before wind shear gets a hold of it.

The most dangerous threat we face in a quiet hurricane season is complacency. There are plenty of examples of slow years pumping out a major storm. The slow 1997 hurricane season produced Hurricane Danny, a destructive storm on the Gulf Coast that caused nine-figure damages and dropped more than three feet of rain on Dauphin Island, Alabama. The posterchild for "don't let a quiet season fool you" is Hurricane Andrew, forming in the middle of August during the otherwise-quiet 1992 hurricane season.

[Satellite Image: RAMMB/CIRA]

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August 10, 2018

Here Are the Best Ways You Can Get Emergency Weather Alerts

I think I've written the phrase "keep an eye out for warnings" in every post I've ever written about thunderstorms. Urging folks to listen up for weather alerts is a mainstay of daily weather forecasts. Most bad storms are warned in advance, but judging by the amount of people who say "we had no warning!" after a major disaster, it makes you wonder just how many people are listening for warnings at all.

I have so many weather alerts coming at me during severe weather that the apartment sounds like WUPHF from The Office when there's a severe thunderstorm nearby. I've long been open about the recent reemergence of storm anxiety. There were a couple of times in college I came close to finding myself in a dangerous spot because I didn't hear a severe thunderstorm or tornado warning. One of my roommates chose not to wake me up for a tornado warning one morning even as the sirens blared outside—the tornado touched down not far from campus.

It would be pretty embarrassing if I were to die in a tornado or earn myself a new head shape thanks to a hailstone. Could you imagine the fun the tabloid websites would have with that one? Storm Clown Torn Down By Cloudy Beatdown. Well, regardless of the reasoning, I try my best to stay ahead of any storms that come my way, and that's something we should all strive to do.

Meteorologists and reporters always tell you to listen for warnings, but what's the best place to look to make sure you hear every warning every time? Here's how I get my warnings.

NOAA Weather Radio

Source: Amazon

I have a NOAA weather radio. These devices are like smoke detectors for the weather. The radios themselves are a bit outdated compared to the technology we have today, but they're a fantastic backup device when dangerous weather is on its way.

Each county/parish in the United States has a unique six-digit identifier (called a SAME code) that you can program into your weather radio. If you tune to the right frequency for your area, the radio will listen for that county's code to come across in a watch or warning and it'll sound a loud siren and turn on the audio feed when it hears that code in the broadcast. You know that annoying screeching sound in the Emergency Alert System? That's actually a coded message similar to dial-up, and it's that tone the radio listens for and uses to sound an alert.

A basic SAME-enabled weather radio costs somewhere around $30 depending on where you look. More advanced radios—ones that allow you to program which alerts you want to hear and which you'd rather ignore—are a little more expensive, but worth it if you want to tune out some alerts that don't apply to you.

The Weather Channel's Bot on Facebook Messenger

One of the most surprising tools I've found useful during severe weather is The Weather Channel's bot on Facebook Messenger.


Facebook Messenger allows companies to set up bots to communicate with you through automated messages. You can use Messenger to do things like order food, discover music through Spotify, receive breaking news alerts from NBC News, and get weather forecasts and severe weather alerts from The Weather Channel.

The Weather Channel's severe weather alerts are usually the very first notification I get when a watch or warning is issued for my town. These alerts actually come through to me on Facebook Messenger a second or two before my weather radio goes off.

The only downfall to these alerts is that they don't follow you around when you're out and about. You only receive alerts for the location you program into the app. Much like weather radios, this Messenger bot is a great tool if you're at home or the office, but it's not the ideal source for warnings when you're out traveling.

Wireless Emergency Alert System

The Wireless Emergency Alert System is a default feature on all modern smartphones sold in the United States. The system sends out emergency alerts to users based on their location. This is a great improvement over the county-based method in that only people in a tornado warning will receive a tornado warning. This cuts down on the Crying Wolf effect and ensures the folks who are in harm's way know that they need to take the alert seriously.

The only problem with wireless emergency alerts is that people tend to deactivate the feature after one or two annoying disruptions. The main purpose of the system, as with on television and radio, is to allow the President of the United States to quickly communicate with the public in case of a national emergency. The most common use, though, is for severe weather. These alerts are typically sent out for tornado warnings and flash flood warnings, but they can be used for hurricane warnings in coastal areas and even dust storm warnings in desert regions.

It's a really good idea to look in your phone's settings and make sure these alerts are activated. They may be annoying, but the NWS has found at least one case where these alerts were directly responsible for saved lives.


There are more weather apps available on Android and iOS than anyone could possibly cover in one blurb. Heck, I've written enough words about the trustworthiness of apps to fill a book. Most reputable weather apps give you timely severe weather alerts based on your location. If you're going to rely on an app for a potentially life-saving warning, I'd rely on one of the big ones—someone like The Weather Channel, Wunderground, AccuWeather, or WeatherBug.

I try to shy away from apps when I'm under the threat for severe weather. My apps sometimes tell me when there's an alert and sometimes they don't. I have The Weather Channel and Wunderground apps on my phone and they both stopped giving me alerts months ago. I don't know if an update tripped a setting or what.

Situations like that are why I like redundancy. I like it when my phone and radio and TV all go off at the same time because I know I'm covered when it suddenly sounds like I won a few bucks on a dorky slot machine.

Code Red Alerts

A growing trend among towns and counties in the United States is to allow residents to sign up for "Code Red" alerts. These services allow localities to push out emergency alerts to people ahead of events like dangerous weather, police activity, boil water advisories, and road closures.

My town in North Carolina, along with many other communities around the country, subscribe to Code Red alerts from OnSolve. Through this program, I receive a text message, email, and phone call when there's an emergency in my area. The lead time is comparable to NOAA Weather Radio. I've only ever had a one-minute delay at most.

Check your city or county's website to see if your local government is signed up for the program.

Television and Radio

When all else fails, it never hurts to flip on the TV or listen to an AM/FM radio. Emergency alerts are broadcast within a few minutes of the issuance of a severe weather alert. Television alerts are usually more useful than ones broadcast over AM/FM radio since they're more targeted to your county. Emergency alerts on the radio have to cover the station's entire listening area.

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August 6, 2018

Major Hurricane Hector Will Likely Pass South of Hawaii This Week

Hurricane Hector is a powerful category four storm with sustained winds of 140 MPH as it entered the central Pacific basin on Sunday night. The hurricane will likely remain south of Hawaii as it makes its closest approach this weekend, but a small northward change in its track could bring dangerous conditions close to the islands.

Hector is downright impressive on satellite imagery today. Its appearance reflects its strength. The storm has a solid eye, thick core, and good outflow. It's unsettling to see a storm this strong in any ocean basin let alone moving in the general direction of heavily-populated islands.

The hurricane will make its closest approach to the Hawaiian Islands between Tuesday night and Wednesday night. Most strong storms in the past that have moved through Hurricane Hector's current location stayed south of the islands and it looks as though this one will do the same. Assuming Hector stays south as forecast, the greatest threat to the islands will be rough surf and rip currents.

The hurricane's track depends on the strength of a ridge of high pressure to the north of the Hawaiian Islands. The outer edge of a high acts like a guardrail for hurricanes, steering them along the outer periphery of the ridge. A stronger ridge will steer Hurricane Hector farther south of Hawaii, while a weaker ridge will allow the storm to track farther north and closer to the 50th state. If the ridge turns out to be weaker than forecast and Hector jogs north, dangerous conditions can't be ruled out on the Big Island on Wednesday.

The Central Pacific Hurricane Center—the NHC's counterpart in Honolulu—expects that the hurricane is at or very near the strongest it'll get this week. Dry air from the north is starting to wrap around the hurricane and will soon start chipping away at its organization, forcing the storm to slowly weaken as it makes its closest approach to Hawaii.

The close approach of a hurricane is the last thing Hawaii needs at the moment. The May 3 eruption of Kilauea on the southeast coast of the Big Island destroyed entire neighborhoods and the lava flow is still going three months later. A large wildfire also broke out on the island of Oahu this weekend, consuming at least 5,000 acres of land and several homes.

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August 1, 2018

Damaging Winds and Isolated Tornadoes Possible on the East Coast on Wednesday

A threat for severe weather will accompany thunderstorms that pop up east of the Appalachians this afternoon. The Storm Prediction Center has issued a slight risk for severe weather—a 2 on a scale from 1 to 5—due to the threat for damaging winds and an isolated risk for tornadoes and large hail. The threat shouldn't be widespread, but any storm that develops could get strong in a hurry.

The eastern United States is deep in a gross weather pattern that just doesn't want to go away. A strong Bermuda High over the western Atlantic is funneling rich tropical moisture as far north as the Canadian Maritimes. This is why the East Coast has been so unusually muggy and wet for the past couple of weeks.

Source: Tropical Tidbits
A sharp trough stretching from the Great Lakes to the Gulf Coast on Wednesday will force thunderstorms to develop along and east of the Appalachian Mountains once daytime heating sufficiently destabilizes the atmosphere. There's enough wind shear in the atmosphere that conditions are favorable for storms to organize into squall lines—where damaging winds would be the greatest threat—or even isolated supercells, where large hail and tornadoes could occur.

It's not hard for thunderstorms in the middle of the summer to produce damaging wind gusts, especially in the southeastern United States where storms have ample moisture to work with. The severe weather threat today is exactly where you'd expect to see severe thunderstorms at the beginning of August.

Not only is there a risk for severe weather, but we can't discount the threat for flash flooding where storms develop. Flash flood watches are in effect from the Alabama coast all the way up to northeastern Pennsylvania. This region has seen a lot of rain recently. Parts of Pennsylvania and Maryland saw more than a foot of rain last week. The combination of soggy ground and the potential for torrential rain in any storms that form will heighten the risk for flash flooding through the end of the week.

It's a good idea to check your smartphone to make sure that emergency alerts are activated. People like to shut those off after one too many AMBER Alerts or flash flood warnings, but it's really helpful when you're out and about and a tornado warning is issued for your location.

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