Remember when the southern Plains had so much heavy rain this spring that the storms straight-up murdered their years-long drought in something like four weeks? The good ol’ days! The region is starting to slip back into a drought, but it’s not too late for things to improve again.
It’s been a little hot in the south this year, and neither heat nor dry conditions are unusual in the southern Plains during the summer. The region stays hot and calm in July and August due to the ridge of high pressure that builds up over Texas (the same reason there’s a monsoon season in the southwest). These ridges are often called “death ridges” or “heat domes” because they deflect all the active weather around the edge of the high, keeping everyone caught beneath them hot, dry, and desperate for water.
Just like the extreme heat of the oven bakes the moisture right out of a nasty meatloaf, so too does the relentless summer heat take a toll on the ground beneath our feet.
Let’s look at the weather so far this summer in Dallas and the smaller (but not lesser) Fort Worth, which nobody ever remembers. Yesterday was the 66th day of meteorological summer, and during that time between June 1 and August 5, DFW Airport has only seen measurable rain on eight days. The airport has picked up 4.87 inches of rain so far this summer, which is a little more than an inch below average.
Look at that heat, though. Dallas hasn’t seen a high temperature below 95°F since July 11, and it’s been 97°F or hotter every day since July 17. That’s not unusual, of course, seeing that the normal high temperature at DFW Airport is 97°F from July 25 through August 17. It’s mind-boggling that millions of people can live where there’s such cruel, inhospitable summer heat and humidity that lasts for so long. But anyway...that kind of heat and lack of precipitation has taken its toll.
Here’s what your drought looked like at the beginning of March:
And here’s what it looked like near the end of June, after the deluge:
And that brings us to this morning’s update of the drought monitor:
When you have intense sunshine baking the ground for weeks at a time with little or no precipitation to keep the soil from resembling The Thing, you’re going to start slipping back into some level of drought. Thankfully, the intense, flooding rainfall seen across the southern Plains late this spring all but erased the drought that built up for years across the region. This gave the area’s soils and bodies of water a good starting point to go into a hot, dry summer without suffering as much as they would have otherwise.
Even though we have small pockets of moderate to severe drought in Texas, the deficit is only a couple of inches at this point, and it’s nothing that can’t be made up with a few days of heavy showers and thunderstorms (or a good tropical disturbance moving through). What’s more concerning is the growing drought in the Carolinas and the ongoing drought in southeastern Florida, but these deficits will hopefully begin to dwindle if our strengthening El Niño holds through winter and follows historical trends.
The southern United States—from California straight through to the Carolinas—tends to see a cooler- and wetter-than-normal winter when a strong El Niño is present. The warmer waters in the eastern equatorial Pacific Ocean help nudge the subtropical jet stream farther north, allowing disturbances and storm systems to develop near the jet and drench the region with precious, precious rain. The Climate Prediction Center says that the pattern is favorable for above-average precipitation in the entire southern half of the country this winter, so hopefully it will benefit California as much as it benefits places like Texas or the Carolinas.
[Images: AP, author]