<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/HeraldCitz1.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/HeraldCitz1.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/HeraldCitz1.jpg?v=ap&w=980&h=551 800w" > A boat rests on a car amid the total destruction of a home on the west edge of Cookeville, Tennessee, after a March 3, 2020, tornado. (Jack McNeely/Cookeville Herald-Citizen)

At a Glance We examined 10 years of warnings issued by the NWS to find which offices issue the most.

Due to severe thunderstorm and tornado warnings, most are in the South and central U.S.

We also broke down the most warnings issued for several other concerns.

The National Weather Service issues tens of thousands of weather warnings each year for severe thunderstorms, flooding, high winds, winter storms, tropical storms, coastal impacts and extremes in temperature.

That prompted us to ask which areas of the country are warned most.

To answer this, we compiled over 300,000 NWS warnings issued in the 50 U.S. states from 2010 through 2019 using an online tool developed by Daryl Herzmann of Iowa State University. We focused on warnings, rather than advisories, to capture the higher-end weather events, but also included high surf advisories, which are more commonly issued rather than high surf warnings along the East Coast.

There are 122 NWS forecast offices, each responsible for issuing forecasts and warnings for a defined area of the 50 states, as well as Guam, American Samoa, Puerto Rico and the U.S. Virgin Islands. (Editor's note: The online tool we used wasn't able to scrape warnings issued by NWS offices serving American Samoa, Guam, Puerto Rico and the U.S. Virgin Islands.)

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/wfo-map.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/wfo-map.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/wfo-map.jpg?v=ap&w=980&h=551 800w" > National Weather Service forecast office locations and their corresponding county warning areas of coverage. (NOAA/NWS)

Based on our calculations, the 10 NWS offices which issued the most warnings in the 2010s were largely in the mid- and lower Mississippi Valley or the Southern Plains.

The Norman, Oklahoma, NWS office, serving central and western Oklahoma and extreme northwestern Texas, led the pack with over 8,700 warnings. The Jackson, Mississippi, office came in second with over 8,300 warnings.

You can see the entire dataset of warnings considered broken down for each NWS office in the 50 states in the links below. You might have to scroll right to see all the data.

(Warnings By NWS Office 2010-2019: Part 1 | Part 2 | Part 3)

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/nws-top10-warning-offices.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/nws-top10-warning-offices.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/nws-top10-warning-offices.jpg?v=ap&w=980&h=551 800w" > The 10 National Weather Service offices which issued the most weather warnings from 2010 through 2019. (Data: Daryl Herzmann/IEM/Iowa State University)

There's a straightforward reason these offices issued the most warnings.

Of the 318,053 warnings issued in this 10-year period, 60% were severe thunderstorm warnings. Another 25% were either flash flood or river flood warnings.

These 10 NWS offices serve areas that are most frequently affected by the combination of severe thunderstorms and flooding.

On an active day, an NWS office may issue dozens of short-lived severe thunderstorm, tornado and flash flood warnings, each covering part of one or more counties for an hour or less.

During the historic April 27, 2011, tornado Super Outbreak , over 300 tornado warnings were issued by NWS offices in 24 hours.

By contrast, for a winter storm, an NWS office typically issues one winter storm or blizzard warning over a larger area for several hours or a few days, covering the entire duration of the snowstorm. Similarly, a period of excessive heat and humidity or dangerous wind chills can be covered by a single warning from each NWS office.

As you can see, the number of warnings per office is biased to a significant extent by how frequently severe thunderstorms are present in each of their forecast areas.

So let's break this down by weather phenomenon to see which NWS offices issue the most warnings for, say, snow and ice, or flash flooding.

The maps below, generated from Herzmann's website, reveal some interesting insights. You can click on the magnifying glass in the lower right corner of each map for an enlarged version.

Severe Thunderstorms and Tornadoes

Severe thunderstorms are defined as those that produce at least one of the following: tornadoes; hail of at least 1-inch diameter; wind gusts of at least 58 mph; or wind damage, such as to trees, power lines or buildings.

Keep in mind: the number of severe thunderstorm and tornado warnings do not correlate to the actual number of severe thunderstorms or tornadoes. Some warnings are issued for storms that have a potential to produce severe weather based on radar but don't.

The layout of the 192,117 severe thunderstorm warnings in the 2010s matches well with NOAA's severe thunderstorm climatology . There are two maximum corridors, one roughly north to south through the Plains and another west-to-east corridor through the Southeast from the Ozarks of Arkansas and southern Missouri through the western Carolinas.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/severe-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/severe-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/severe-warn.jpg?v=ap&w=980&h=551 800w" > Severe thunderstorm warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

The Jackson, Mississippi, NWS office issued over 1,000 tornado warnings from 2010 through 2019, most of any office in the nation. The Slidell, Louisiana, office was a distant second place, followed by the Shreveport, Louisiana, and Norman, Oklahoma, offices.

At first glance, this lower Mississippi Valley warning maximum doesn't mesh with the longer-term average number of actual tornadoes , from Texas to Kansas.

However, that 20-year average compiled by NOAA ended in 2010, prior to the April 2011 Super Outbreak and several other active tornado years in the Deep South. Mississippi set a state record yearly tornado count in 2019 .

Also, severe thunderstorms and tornadoes can occur in the Deep South any time of year, even in winter , which may be responsible for those higher tornado warning totals, compared to the Plains.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/tornado-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/tornado-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/tornado-warn.jpg?v=ap&w=980&h=551 800w" > Tornado warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

Flash Flooding

Rainfall that produces the type of sudden water rises and falls on streets, creeks or streams is known as flash flooding.

Again, with the caveat of warnings not necessarily matching the number of events, the lower Mississippi Valley stands out as a frequent flash flood corridor.

NWS forecast offices serving Washington D.C. and Philadelphia also issued a larger number of flash flood warnings relative to surrounding offices, given the large, sprawling metro areas with concrete leading to higher runoff.

You may be surprised to see the large number of flash flood warnings issued in the Desert Southwest. NWS-Las Vegas was the nation's leader in such warnings in the 2010s.

A normally dry creek or streambed known as a wash, or arroyo, can fill quickly with fast-moving water, posing a danger where roads cross, or where they pass near buildings or homes.

Heavy rain can also run off quickly on city streets and over dry, mountainous terrain, proving dangerous to motorists and hikers.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/flash-flood-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/flash-flood-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/flash-flood-warn.jpg?v=ap&w=980&h=551 800w" > Flash flood warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

High Winds

The distribution of high wind warnings matches well with average wind analyses .

The top offices in the nation are in the High Plains, from Montana to West Texas.

The Cheyenne, Wyoming, forecast area includes one of the windiest places in the U.S., crossed by Interstate 80 between Laramie and Cheyenne. The Midland, Texas, forecast area includes Guadalupe Pass, a notoriously windy mountain along the Texas and New Mexico border.

These warnings are also common along parts of the Pacific Northwest coast and Alaska, associated with strong Pacific storms, and in Southern California with Santa Ana wind events.

In the East, high wind warnings are most common in the Northeast, particularly southeastern New England, from strong coastal storms that may brush Nantucket, Martha's Vineyard and Cape Cod.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/high-wind-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/high-wind-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/high-wind-warn.jpg?v=ap&w=980&h=551 800w" > High wind warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

Snow, Ice

The criteria for winter storm warnings varies by location. A 2-inch snowfall is a higher-impact event in Houston than Detroit.

Therefore, the distribution of winter storm warnings isn't too surprising. Northern Alaska and the Rockies lead the pack, as these higher latitudes or higher elevations can have significant snow over a longer time of year.

Winter storm warnings are common each "winter" atop the volcanic peaks in Hawaii. They've even been issued on rare occasions in Deep South Texas and North Florida.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/winter-storm-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/winter-storm-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/winter-storm-warn.jpg?v=ap&w=980&h=551 800w" > Winter storm warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

Ice storm warnings are much less frequently issued, mainly for events where damaging ice accumulations are expected in the absence of snow.

However, the map below shows a few ice storm corridors in the interior Northeast, from Oklahoma to Tennessee and in the upper Midwest.

The nation's ice storm warning leader, however, is the Portland, Oregon, office.

This is because cold air plunging southward out of western Canada often squeezes through the Columbia River Gorge and empties into western Oregon's Willamette Valley. When a Pacific storm pumps moisture over that subfreezing air, accumulating ice can result in Portland, Salem and Eugene, Oregon.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/ice-storm-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/ice-storm-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/ice-storm-warn.jpg?v=ap&w=980&h=551 800w" > Ice storm warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

Excessive Heat

The NWS issues excessive heat warnings when the combination of heat and humidity will be much higher than a typical summer day in any location, posing a danger to those outside for long periods of time or those who lack air conditioning.

It's no surprise the Desert Southwest leads the way in these warnings, especially considering days when air temperatures alone can soar into the 110s or 120s.

Otherwise, the hot, humid corridor from Kansas and Oklahoma to the Mississippi Valley and the urban corridor from Washington D.C. to New York City are other heat warning hot spots.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/excess-heat-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/excess-heat-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/excess-heat-warn.jpg?v=ap&w=980&h=551 800w" > Excessive heat warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

Wind Chill Warnings

For dangerous wind chills, nowhere in the U.S. tops northern Alaska.

Just behind NWS-Fairbanks are a number of offices in the Northern Plains, including Cheyenne, Wyoming; Bismarck, North Dakota; and Duluth, Minnesota.

Parts of the Northeast also have an average of two to three wind chill warnings a year from northern New England into New York state.

You'll notice a number of wind chill warnings in South Texas and Florida. As with winter storm warnings and excessive heat warnings, the criteria is markedly different in those southern locations.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/wind-chill-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/wind-chill-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/wind-chill-warn.jpg?v=ap&w=980&h=551 800w" > Wind chill warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

Coastal Flooding

The NWS issues coastal flood warnings when flooding from water driven ashore is expected to pose a serious risk to life and property.

The distribution of these warnings nicely illustrates the typical area where coastal storms off the East Coast tend to intensify, generally near or off the coast of North Carolina. Note the marked increase in warnings issued by the NWS-Wakefield, Virginia, office (51) compared to the Morehead City, North Carolina, office to its immediate south (19).

Also, note the higher number of warnings issued by NWS-Fairbanks, for coastal areas along the Beaufort, Bering and Chukchi seas.

With planetary warming leading to diminished sea ice, strong Pacific storms may increasingly drive flooding into the vulnerable, low-lying Alaskan Arctic coast in the years ahead.

In the Great Lakes, lakeshore flood warnings were most commonly issued by the Buffalo, New York, office, with both the Cleveland and Detroit offices a distant second place.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/coastal-flood-warn.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/coastal-flood-warn.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/coastal-flood-warn.jpg?v=ap&w=980&h=551 800w" > Coastal flood warnings issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

High Surf

We made an exception in this case to look at advisories, rather than warnings. While high surf warnings are issued along the West Coast – and in rare occasions, along the Gulf Coast – they're not issued along the East Coast.

Hawaii is the undisputed king of high surf, often in the winter months as powerful Pacific storms cross well north of Hawaii, sending large swells to the north shores of the islands.

In the Lower 48, Southern California often experiences large swells from Pacific storms, distant Eastern Pacific hurricanes, even from storms thousands of miles away in the Southern Hemisphere.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/high-surf-advisory.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/high-surf-advisory.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/high-surf-advisory.jpg?v=ap&w=980&h=551 800w" > High surf advisories issued by local NWS forecast offices from 2010 to 2019. (Daryl Herzmann/Iowa State University)

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.