Here Are Maps of All the Areas Hit by Tornadoes So Far This Year

Dennis Mersereau · 06/26/14 03:13PM

Even though 2014 is another relatively quiet year for tornado activity, it's pretty interesting to see which areas of the country were most heavily affected by the couple of tornado outbreaks we've seen over the past six months.

Why Do Weather Maps Ignore Canada?

Dennis Mersereau · 06/23/14 03:22PM

Weather doesn't stop at the borders, but you would never know it by looking at an American weather forecast. Our friends north of the border are inundated with our forecasts, but rarely do they actually benefit from the information. Why do our weather maps stop at the border?

These Simple Maps Show How Little of the United States Is Populated

Dennis Mersereau · 06/20/14 11:05AM

In an ever-growing effort to provide valuable weather information — or just a vulgar display of automated GIS skills — the National Weather Service is tweeting out images that show how many people are impacted by severe weather. The exercise shows just how little of the United States is populated.

Blitzortung Is One of the Best, Most Mesmerizing Websites Out There

Dennis Mersereau · 06/12/14 11:18AM

The internet is saturated with websites that give you weather information, and frankly, most of them suck. Very few allow you to see lightning around the world in real-time, and even fewer give you this data for free. But there is one nugget of gold tucked deep in the confines of Europe that gives you the best of the best, all for free.

Colorado Can't Catch a Break This Year. What Gives?

Dennis Mersereau · 06/09/14 01:10PM

Colorado just can't catch a break. When it's not burning or flooding, it's catching hell from the sky, with hailstones the size of baseballs and a constant conga line of tornadoes raking the eastern half of the state. How common is extreme weather in Colorado, and is this the new normal?

More Than 2,000 Severe Weather Warnings Issued in the Past Week

Dennis Mersereau · 06/08/14 09:28PM

Here are all of the severe thunderstorm (blue), tornado (red), and flash flood warnings (green) issued in the past 7 days. To say that this was an "active week" is an understatement. The past week has seen nearly 2,000 severe weather warnings go into effect, and this doesn't include the 200+ warnings that were issued on Sunday.

Dennis Mersereau · 06/06/14 04:19PM

Oklahoma could see more than eight inches of rain over the next seven days if current forecasts hold true. That much rain over the Plains states would do wonders toward alleviating the extreme to exceptional drought plaguing the region.

What Parts Of The Country Get The Worst Weather Predictions?

Reuben Fischer-Baum & Dennis Mersereau · 05/02/14 11:50AM

When you check the day's temperature or see if it's going to rain on your way to work, the answer can vary widely depending on where you look. Luckily, the website ForecastAdvisor—which grades the accuracy of U.S. forecasting outlets such as The Weather Channel, National Weather Service (NWS), CustomWeather, and AccuWeather—can help you sort the good from the bad. If you head over to their site you can plug in your zip code and see your local numbers, but they were kind enough to provide us with their raw data for 2013, and the results are pretty surprising.

Dennis Mersereau · 05/01/14 04:30PM

Check out this excellent interactive feature created by Brian Crumpler on the Mayflower/Vilonia, Arkansas EF-4 tornado that touched down on Sunday. The feature blends together radar images, maps, and pictures of the damage to give you an in-depth look at how the tornado evolved along its 40-mile path.

Cut-Off Low Creates an Awesome Pinwheel of Dry Air Over the Southeast

Dennis Mersereau · 04/19/14 01:43PM

A large low pressure system sitting over the southeastern United States is creating quite the sight on satellite imagery this afternoon as it wraps dry air into its core. This is a water vapor image from the GOES satellite, showing the moisture in the atmosphere around 10,000 feet up. Warmer colors indicate drier air, and cooler colors indicate moist air.

Historic Weather Maps: Tornado Outbreak of April 18, 1880

Dennis Mersereau · 04/18/14 10:30AM

This was a weather map drawn back on April 18, 1880, showing the weather at 1AM Eastern for every weather station in the United States. Less than 24 hours later, dozens of tornadoes would tear across the central United States, killing over 100 people.

Here's a Map of Every Severe Weather Warning Issued in the Last Week

Dennis Mersereau · 04/05/14 12:30PM

The United States saw 752 severe weather warnings issued across 25 states between last Saturday and yesterday evening. On the map above, blue boxes indicate a severe thunderstorm warning, red indicates a tornado warning, green indicates a flash flood warning, and teal indicates a special marine warning.

Map Porn: Average Date of Year's First Tornado Warning

Dennis Mersereau · 04/03/14 02:30PM

This map shows the average date that each National Weather Service forecast office issues its first tornado warning every year, based on data from 1986-2013. It's pretty illustrative of how tornado climatology tends to work in the United States. The Deep South sees its first round of severe weather during the winter, and it radiates outwards as the atmosphere begins to warm up through the country.

Map Porn: Decaying Squall Line Forms Near-Perfect Cane Over Midwest

Dennis Mersereau · 03/28/14 10:00AM

Satellite images over the past few weeks have been anything but boring, and last night's thunderstorms were no exception. A weakening squall line moving through Illinois and Missouri formed into almost a perfect cane shape as the northern end wrapped around a strengthening low west of Chicago.