8 Climatic Facts About Our Abnormally Warm Winter

Christof Stache/AFP/Getty Images
Christof Stache/AFP/Getty Images

It was warm this winter. Freakishly warm, in fact. It was warm enough that we probably should have felt guilty for enjoying it so much. After all, any time you can open your windows when you’re supposed to be shivering and watching travel shows for warmth is a strange situation. Most of the United States just lived through one of the warmest Februarys on record to close out one of the warmest winters on record. Here are some statistics that will show you just how unusually balmy it’s been for the past three months.

1. THIS FEBRUARY WAS WARMER THAN NORMAL.

A map of how warm this February was compared to previous years. Stations showing a ‘1’ experienced the warmest February ever recorded at that location. Image Credit: SERCC

 
It shouldn’t come as any shock that February’s temperatures were above-average when you crunch the numbers. Out of 888 weather observing stations across the lower 48, a solid 60 percent of those stations (or 534 locations) saw their top-10 warmest February on record this year. Even worse is that 186 of those locations—scattered from the depths of Texas to the Canadian border—recorded their all-time warmest February, with some records stretching back more than 100 years.

2. THE WHOLE WINTER WAS WARMER THAN NORMAL.

Not only was this past February a record-breaker, but the whole winter was warm on average. Data from the Southeast Regional Climate Center shows that over half of those 888 weather observing stations in the contiguous United States saw this winter place among the top ten warmest winters ever recorded, with almost all of the toasty stations residing east of the Rocky Mountains. Most of the all-time warmest winter records were set in the southern part of the country, including cities like Houston, Texas, and Raleigh, North Carolina.

3. THE WARMTH KEPT MOST OF THE SNOW AT BAY.

Taken just one day apart in early February, two views of the downtown Manhattan skyline—one warm and sunny, the other obscured by snow—as seen from the Brooklyn Heights Promenade. Image Credit: Spencer Platt/Getty Images

 
As you can imagine, you’re not going to find very much snow when it’s relatively toasty out there. There have been other winters with less snow than most places saw this year, but the differences are negligible. Take Washington D.C., for example. Washington National Airport, which sits just across the Potomac River from the capital city itself, typically sees about 15 inches of snow every year. They’ve recorded just over an inch of snow this year. On the list of least-snowy winters in the nation’s capital, this winter ranks fourth since records began in 1940.

4. CHICAGO SAW NO SNOW IN JANUARY OR FEBRUARY.

Even more unusual is the fact that Chicago went through the entire months of January and February without seeing one lick of snow cover the ground. According to the city’s National Weather Service office, this was the first time in the city’s 146 years of recording weather observations that they didn’t see any snow on the ground during the dead of winter. The city saw a foot-and-a-half of snow spread out over several storms during the month of December, but all of that snow melted by Christmas. The most they’ve seen since then is a “trace” of snow, which is snow that falls but instantly melts when it hits the ground.

5. THE GREAT LAKES WERE RELATIVELY ICE-FREE.

While we’re looking toward the Midwest, it’s worth noting that the Great Lakes were surprisingly ice-free this season. The five lakes only saw about 15 percent of their surface covered by ice during the season’s maximum extent on February 8, and what little ice did form this year is rapidly melting as warm air continues to bathe the enormous bodies of water. Since NOAA began keeping records back in 1973, a typical winter sees a little more than half of the Great Lakes covered with ice during the peak of winter, but the coverage has been as low as 11 percent, a record achieved in 2002.

6. THE LEAVES LOVED IT, THOUGH.

A map showing how unusually early (or late) leaves first showed up on trees in 2017 compared to normal. Image Credit: USANPN

Humans aren’t the only organisms enjoying the reprieve from winter’s grip. The USA National Phenology Network tracks the extent of trees budding and growing leaves as spring begins to set in. According to their observations, almost every part of the United States that has leaves on its trees right now saw those leaves appear a full three weeks ahead of schedule—what it calls "very large anomalies." This is welcome news for the birds and the bees, but if there’s a sudden cold snap in March—which isn’t unheard of—it could do some serious damage to any plants that are suddenly more vulnerable than normal.

7. THE WARMTH LED TO SOME SEVERE THUNDERSTORMS.

When you put an active weather pattern together with warm and unstable air, it’s almost inevitable that you’ll wind up with strong thunderstorms at some point. We saw several rounds of severe weather this spring, resulting in at least three fatalities on the last day of February. Severe weather is fairly common in the southeast due to its proximity to muggy air over the Gulf of Mexico, but severe weather stretched unusually far north this year. A tornado that touched down in western Massachusetts on February 25 was the only tornado ever recorded in the state during the month of February, and quite possibly the farthest north we’ve ever seen a tornado since reliable records began in 1950.

8. SO WHY HAS IT BEEN SO WARM?

Why has it been so warm in the east and so cool and active out west? It has to do with the jet stream. For the past couple of years, there’s been a huge ridge in the jet stream over the West Coast that kept them warm and dangerously dry, while the jet stream dipped south and brought cooler, more active weather to the rest of the United States. That pattern broke this year, essentially reversing itself and keeping the warmth-inducing ridge out east while the jet stream in the west keeps dipping south and bringing them a steady stream of rough weather. One theory as to why the pattern flipped is the disappearance of the infamous “Blob,” a nickname given to an unusually warm area of water in the northeastern Pacific Ocean. That water cooled off, which may have allowed the jet stream to readjust itself into the pattern we’ve seen this winter.

12 Powerful Facts About Hurricanes

iStock/shaunl
iStock/shaunl

Hurricanes are a stunning, and dangerous, display of nature’s power. They’re some of the largest and most intense storms nature can produce. Today, we know more about these systems and have an easier time measuring and predicting them than ever before. There’s more than meets the eye when it comes to hurricanes. As the 2019 hurricane season kicks off (it runs from June 1st through November 30th), here are some things you might not know about these dangerous storms.

1. Hurricanes are only "hurricanes" around North America.

A tropical cyclone is a compact, low-pressure system fueled by thunderstorms that draw energy from the heat generated by warm ocean waters. These tropical cyclones acquire different names depending on how strong they are and where in the world they form. A mature tropical cyclone is called a hurricane in the Atlantic and eastern Pacific Oceans. What’s known as a hurricane in the Atlantic is called a typhoon near Asia and simply a cyclone everywhere else in the world.

2. Hurricanes come in all shapes and sizes.

Not all hurricanes are picture-perfect. Some storms can look so disorganized that it takes an expert eye and advanced technology to spot them. A full-fledged hurricane can be as small as a few dozen miles across or as large as one-half of the United States, as was the case with Typhoon Tip in the western Pacific Ocean in 1979. The smallest tropical cyclone on record was 2008’s Tropical Storm Marco, a tiny storm in the Gulf of Mexico that almost made it to hurricane strength. Marco’s strong winds only extended 12 miles from the eye of the storm—a distance smaller than the length of Manhattan.

3. The greatest danger in a hurricane is in the eyewall.

The spiraling bands of wind and rain that radiate from the center of a hurricane are what give these storms their distinctive buzzsaw shape. These bands can cause damage, flooding, and even tornadoes, but the worst part of a hurricane is the eyewall, or the tight group of thunderstorms that rage around the center of the storm. The most severe winds in a hurricane usually occupy a small part of the eyewall just to the right of the storm’s forward motion, an area known as the right-front quadrant. The worst damage is usually found where this part of the storm comes ashore.

4. The eye of a hurricane is very warm.

The core of a hurricane is very warm—they are tropical, after all. The eye of a hurricane is formed by air rushing down from the upper levels of the atmosphere to fill the void left by the low air pressure at the surface. Air dries out and warms up as it rapidly descends through the eye toward the surface. This allows temperatures in the eye of a strong hurricane to exceed 80°F thousands of feet above the Earth's surface, where it’s typically much colder.

5. You can tell a lot about a hurricane by its eye.

Like humans, you can tell a lot about a hurricane by looking it in the eye. A ragged, asymmetrical eye means that the storm is struggling to strengthen. A smooth, round eye means that the storm is both stable and quite strong. A tiny eye—sometimes called a pinhole or pinpoint eye—is usually indicative of a very intense storm.

6. Some hurricanes have two eyes.

An eye doesn’t last forever. Storms frequently encounter a process known as an “eyewall replacement cycle,” which is where a storm develops a new eyewall to replace the old one. A storm weakens during one of these cycles, but it can quickly grow even more intense than it originally was once the replacement cycle is completed. When Hurricane Matthew scraped the Florida coast in October 2016, the storm’s impacts were slightly less severe because the storm underwent an eyewall replacement cycle just as it made its closest approach to land.

7. The strong winds that a hurricane creates are only part of the danger.

While strong winds get the most coverage on the news, wind isn’t always the most dangerous part of the storm. More than half of all deaths that result from a landfalling hurricane are due to the storm surge, or the sea water that gets pushed inland by a storm’s strong winds. Most storm surges are relatively small and only impact the immediate coast, but in a larger storm like Katrina or Sandy, the wind can push deep water so far inland that it completely submerges homes many miles from the coast.

8 California rarely sees tropical cyclones.

It can seem odd that California occupies hundreds of miles of coastline but always seems to evade the hurricane threat faced by the East Coast. California almost never sees tropical cyclones because the ocean is simply too cold to sustain a storm. Only a handful of tropical cyclones have ever reached California in recorded history—the worst hit San Diego in 1858. The San Diego Hurricane was an oddity that’s estimated to have reached category 1 intensity as it brushed the southern half of the Golden State.

9. Hurricane hunters fly planes into storms.

Aside from satellite and radar imagery, it’s pretty hard to know exactly what a hurricane is doing unless it passes directly over a buoy or a ship. This is where the Hurricane Hunters come in, a brave group of scientists with the United States Air Force and NOAA who fly specially outfitted airplanes directly into the worst of a storm to measure its winds and report back their findings. This practice began during World War II and has become a mainstay of hurricane forecasting in the decades since.

10. Hurricane hunters drop sensors to measure waves.

The Hurricane Hunters assess the storm with all sorts of tools that measure temperature, pressure, wind, and moisture, and have weather radar onboard to give them a detailed view of the entire storm. They regularly release dropsondes to "read" the inside of the storm. Dropsondes are like weather balloons in reverse: instead of launching weather sensors from the ground into the sky, they drop them down through the sky to the ground. The Hurricane Hunters also have innovative sensors that measure waves and sea foam and use the data to accurately estimate how strong the winds are at the surface.

11. We started naming storms to keep track of them.

Meteorologists in the United States officially started naming tropical storms and hurricanes in the 1950s to make it easier to keep track in forecasts and news reports. Since then, naming tropical cyclones has become a worldwide effort coordinated by the World Meteorological Organization, the United Nations agency responsible for maintaining meteorological standards. Today, the Atlantic Ocean and eastern Pacific Ocean each receive a list of alternating masculine and feminine names that are reused every six years.

12. Names are retired if the storm was especially destructive.

If a storm is particularly destructive or deadly, the WMO will “retire” the name from official lists so it’s never used again out of respect for the families of the storm’s victims and survivors. When a name is retired, another name starting with the same letter takes its place. More than 80 names have been retired from the Atlantic Ocean’s list of names since 1954. Earlier this year, it was announced that the names Florence and Michael were being retired as a result of the damage they caused during the 2018 hurricane season; they will be replaced with Francine and Milton when the list is reused in 2024.

This piece originally ran in 2017; it has been updated for 2019.

Denver is About to Experience Summer and Winter Temperatures Within 24 Hours

iStock.com/mphotoi
iStock.com/mphotoi

In a story tailor-made for exhaustive Weather Channel coverage, Denver, Colorado is about to experience one of the more bizarre weather shifts in recent memory. After an expected Tuesday high of 80°F, residents can anticipate a dramatic shift down to 32°F by midday Wednesday, with an initial half-inch of snow accumulation increasing to up to 7 inches by Wednesday night.

Put another way: Citizens who need to make sure they hydrate in the warm temperatures Tuesday will have to bring out the parkas the following day.

The Denver Post reports that the warm air coming ahead of the cold can result in a clash of air masses, prompting areas of low pressure that can create forceful and damaging weather conditions. The storm could bring winds of up to 60 miles per hour and possibly even cause power outages. Snow accumulation should dissipate by the weekend, when temperatures are expected to climb back into the 60s.

The high temperature record for April 9 in Denver is 81°F, set in 1977.

[h/t The Denver Post]

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