Disruptive weather in a warming world

The summer of 2021 was a glaring example of what disruptive weather will look like in a warming world. In mid-July, storms in western Germany and Belgium dropped up to eight inches of rain in two days. Floodwaters ripped buildings apart and propelled them through village streets. A week later a year’s worth of rain—more than two feet—fell in China’s Henan province in just three days. Hundreds of thousands of people fled rivers that had burst their banks.,,In mid-August a sharp kink in the jet stream brought torrential storms to Tennessee that dropped an incredible 17 inches of rain in just 24 hours; catastrophic flooding killed at least 20 people. None of these storm systems were hurricanes or tropical depressions.

Soon enough, though, Hurricane Ida swirled into the Gulf of Mexico, the ninth named tropical storm in the year’s busy North Atlantic season. On August 28 it was a Category 1 storm with sustained winds of 85 miles per hour. Less than 24 hours later Ida exploded to Category 4, whipped up at nearly twice the rate that the National Hurricane Center uses to define a rapidly intensifying storm. It hit the Louisiana coast with winds of 150 miles an hour, leaving more than a million people without power and more than 600,000 without water for days. Ida’s wrath continued into the Northeast, where it delivered a record-breaking 3.15 inches of rain in one hour in New York City. The storm killed at least 80 people and devastated a swath of communities in the eastern U.S.

What all these destructive events have in common is water vapor—lots of it. Water vapor—the gaseous form of H2O—is playing an outsized role in fueling destructive storms and accelerating climate change. As the oceans and atmosphere warm, additional water evaporates into the air. Warmer air, in turn, can hold more of that vapor before it condenses into cloud droplets that can create flooding rains. The amount of vapor in the atmosphere has increased about 4 percent globally just since the mid-1990s. That may not sound like much, but it is a big deal to the climate system. A juicier atmosphere provides extra energy and moisture for storms of all kinds, including summertime thunderstorms, nor’easters along the U.S. Eastern Seaboard, hurricanes and even snowstorms…

Fascinating – and dangerous – forecasting. Even here in the desert Southwest, we can look forward to drought and unusual cloudbursts. The scariest part being rapid intensification – with circumstances changing dramatically in a matter of hours. Not only an interesting read. Something needing to be added to our understanding of changing weather systems in our future – for simple self-preservation.

Tropical Storm Cindy nears Louisiana

❝ Tropical Storm Cindy formed in the Gulf Tuesday afternoon and was heading toward the Louisiana coast, bringing with it the potential threat of life-threatening flash floods.

As a result, the Gulf coast from the Louisiana-Mississippi border, which includes New Orleans, to the Houston-Galveston area of Texas was under a tropical storm warning — which means tropical storm conditions are expected.

❝ Stacy Stewart, Senior Hurricane Specialist at the National Hurricane Center in Miami, said that what’s notable about Cindy was that some of the storm’s most intense weather was far from its core.

Tropical storm-force winds were extending about 205 miles from the storm’s center, mainly to the north and east, forecasters said.

“It’s a large sprawling system, it’s not a classic tropical cyclone,” Stewart said.

❝ Whether it’s a sign of things to come this season remains to be seen, but NOAA’s prediction of a busier-than-normal hurricane season is ringing true so far.

As much as we often whine about the absence of rain – average annual rainfall here in northern New Mexico is 14+ inches. If we’re lucky. Still, I do not miss the weather on the Gulf of Mexico. Even if I miss the crawfish.

NASA Spots “Hot Towers” in Tropical Storm Frank — which you should start learning about


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As tropical storm Frank was forming in the Eastern Pacific Ocean, NASA analyzed rainfall and cloud heights and found “hot towers” that indicated intensification was likely.

After the Global Precipitation Measurement mission or GPM core satellite passed over System 99E, it quickly strengthened into Tropical Depression 07E and then a tropical storm. The…satellite flew directly above the increasingly organized stormy area on July 21, 2016 at 4:51 a.m. EDT. GPM found some powerful thunderstorms contained intense showers. Rain was measured by GPM’s Dual-Frequency Precipitation Radar instrument falling at a rate of over 7.2 inches per hour in a few of these convective storms.

WTF? Ever been in a tropical downpour? They average about 1½ inches/hour rainfall – up to 6″ max. I’ve been in cities with superb drainage, lots of paving leading to storm drains – at 2″ hour and experienced flooding.

GPM data also provided a 3-D look at the storms. GPM’s radar…slicing through these storms found that some tall thunderstorms were reaching heights of over 9.9 miles…

A “hot tower” is a tall cumulonimbus cloud that reaches at least to the top of the troposphere, the lowest layer of the atmosphere. It extends approximately 9 miles high in the tropics. These towers are called “hot” because they rise to such altitude due to the large amount of latent heat. Water vapor releases this latent heat as it condenses into liquid. Those towering thunderstorms have the potential for heavy rain. NASA research shows that a tropical cyclone with a hot tower in its eyewall was twice as likely to intensify within six or more hours, than a cyclone that lacked a hot tower…

Frank was moving toward the northwest near 12 mph and the NHC forecast a turn to the west-northwest with a decrease in forward speed during the next couple of days. On the forecast track, Frank is expected to move away from the southwest coast of Mexico and pass well south of the Baja California peninsula over the weekend.

Maximum sustained winds are near 50 mph with higher gusts. NHC said some strengthening is forecast during the next 48 hours, and Frank could become a hurricane during the weekend.

I’m not posting this to give you the weather forecast over the eastern Pacific. Just pointing out what’s happening in weather systems during a fairly normal La Nina year. Maybe even lightweight at this point. As a matter of habit in the high desert Southwest we watch for orange tops with hopes of getting a bit of precip. For you folks, elsewhere, it’s a different story.

I’d suggest you start paying attention. “Nobody told me this was coming” ain’t a terrific excuse anymore.