When severe weather threatens, our minds often don’t see flooding as a danger. We often think of tornadoes, gusts of wind, and hail.
But flooding is also a danger; one that is more dangerous than most realize. Direct quote from NWS’s Severe weather 101 pages, “Except for heat-related deaths, more deaths are caused by flooding than any other weather-related hazard.”
We should see some potentially important setups for flash flooding for the rest of the work week.
Today (Wednesday) will have two areas of high opportunity: the Northern High Plains and the South Central Plains.
A low will move into the South Central from Texas. The Gulf moisture would then be pulled northward, and convection would continuously form along the boundary as a result. Simply put, storms will rain down on the same area multiple times a day, leading to the potential for flash flooding – especially in places where saturated soil.
Farther north in the Northern Plains, an upcoming low will help pull in Gulf moisture. The upflow will aid in the creation of convection which, once it hits the available moisture, will potentially cause heavy rain. Storms can also move along the boundary here, leading to the possibility of flash flooding.
ABOVE Thursday, the potential for flash flooding will further extend across the Central/Northern High Plains and also the Lower/Middle Mississippi River. In addition, the west side of Florida will be added to the risk.
Players remain the same for two of these regions:
In the MS River Valley, the lows from the previous day will continue to the northeast. The Gulf humidity is again expected to meet the boundary as convection forms and potentially create trains along it. Heavy rain will be possible regardless of training bands, but training will aggravate the situation.
In the High Plains, the same system from Wednesday will slow and remain over the region, continuing to pull Gulf moisture northward. Again, the upflow will help create convection that will exploit the unusual moisture in the area. Locations with heavy rainfall the previous day will be particularly vulnerable to flash flooding.
In western Florida, an old forward boundary would be the focal point for near-hit hurricanes. As storms penetrate the deep moisture already present on the peninsula, heavy rains can lead to some local flash flooding.
ABOVE Friday, the Northern Plains/High Plains enter the game again. We’ll also be adding the Ohio Valley area and much of the Southern Plains.
Similar lows from two days ago will continue to bring moisture northward to the Northern Delta. Locations with heavy rain on Wednesday, Thursday, or both will have the highest risk of flash flooding.
In the Ohio Valley, disturbances from earlier days will continue to spread to the northeast. Gulf humidity will continue to move northward. Again, training is possible with the greatest flash flood risk anywhere these strips materialize.
In the Southern Plains (mainly south/central Texas), a slow-moving depression will enter the area from the south. Convection that forms will move equally slowly and can lead to storms that linger over a particular area for quite a while. As you can imagine, rainfall can add up quickly in a case like this. Since this can happen in the evening/night, it is important that you know and be prepared if there is a flash flood warning for your area and your vulnerable property.
The precipitation forecast from the NWS plots a few “black spots” of 4 inches or more across the various regions I discussed above. We can clearly identify southern/central Texas (Friday), South Central (Wednesday) and Northern Plains/High Plains (Wednesday through Friday).
Unfortunately, the weekends will bring more rainfall to these soon-to-saturate areas. More on that in the next blog.
About the author
Meteorologist – ’22 Mississippi State Writer for Weather.us and Weathermodels.com. Focus on weather communication. BoyMom x1, CatMom x5. Twitter: @MegGulledgeWX