STUNNING DROUGHT EXPANSION...
Flash Drought
A flash drought is a type of drought characterized by its rapid onset, intensification, and severity over a relatively short timescale, usually within a few days or weeks. This concept has evolved during the last decade as researchers have become more interested in understanding and mitigating the impacts. Flash droughts differ from other drought categories such as meteorological, hydrological, agricultural, ecological, and socioeconomic droughts, in that they develop and intensify more quickly, posing unique challenges for monitoring, prediction, and mitigation.
History
Flash droughts have gained increasing attention from researchers and policymakers due to their significant impacts on agriculture and water resources. The term "flash drought" was coined to describe the rapid onset and intensification of drought conditions, which set it apart from other, more conventional drought types that develop over longer periods.
During the past two weeks much of the central Midwest has met the qualifications of flash drought with little if any rain, hot temperatures, and abundant sunshine. Below you can see the rainfall deficits acquired over the past 14 days.
Those totals are 0-10 percent of normal.
Meanwhile, temperatures have pushed into mid-summer levels with the Quad Cities hitting 91 or above for the 3rd consecutive day Thursday.
In this side by side comparison you can see how dryness has rapidly expanded over the past week.
A closer inspection reveals that 66 percent of the of the Midwest is now in abnormally dry to extreme drought conditions. One week ago that number was just 26 percent. Last summer at this point only 10 percent of the Midwest was in one of the dryness categories.
The USDA indicates 34 percent of the corn crop is within the drought classification.
Beans are slight better at 28 percent.
Much of the region from Iowa east into Illinois and Indiana are highlighted as spots where drought development is likely (or will continue to intensify).
The current weather pattern does offer the prospect of some isolated showers and storms again Friday. However, much like Thursday, forcing is limited and coverage looks spotty and low. Some fortunate locations could get a welcome downpour but most others will see little if any rain, certainly nothing that would damper the evolving drought in any widespread way. The HRRR convective allowing model shows the popcorn nature of the cells which are most likely in the afternoon or evening during peak heating. One spot might see an inch of rain while a mile away nothing more than a sprinkle is noted.
Our friends in central Iowa had a taste of that situation Thursday morning where the doppler indicates nearly 4 inches of rain SE of Des Moines around Indianola. However, outside of that specific pocket, little fell to the east or west. Set-ups like this are often feast or famine.
As expected, later on in the day some localized storms popped up in my area that according to Doppler could have dumped up to 2" of rain between West Branch and Clarence. With steering currents very light the storms move little and rain themselves out. No doubt though, a few lucky folks had some beneficial rain. Far more got skunked.
So Friday appears to be a repeat of Thursday with scattered storms and very isolated cells dumping heavy downpours. After Friday, rain chances decrease again over the weekend as what forcing exists moves further west along with the better moisture. That's apparent in the water vapor. PWAT's Friday are looking very healthy.
By Saturday they have lowered considerably.
By Tuesday night of next week, they have plunged to exceptionally low levels once again! This is due to the mean trough retrograding west enhancing NW flow aloft. That allows a backdoor front to slip in turning winds to the E/NE. Some models hint at scattered storms along the front Monday night but confidence is low on that potential.
Behind the front Tuesday, relative humidity on the EURO is back down to 15-25 percent. You won't get rain in an air mass like that. However, there is a plus in that temperatures will turn cooler. Both the EURO and GFS show a nice drop in temperatures next Wednesday when highs are back in the range of 75-80. At least we have that going for us. Just how cool and for how long is highly debatable. The GFS and EURO are in better agreement tonight indicating the pleasant weather lasts through the end of the coming week
Big picture, the overall pattern and its staunch block doesn't change much the next 10-14 days, it just wavers west and east allowing some noteworthy temperature and humidity fluctuations. The EURO indicates this for readings through June 16th.
In general, rain chances appear few and far between and again, the EURO shows healthy rainfall departures over the throughout the central Midwest.
The next 10 days departures look like this ending June 12th.