7/6 – Rob Knight’s “Wet & Hot” Workweek Forecast
No pattern change today and model soundings actually show a slightly bump in precip chances, so expecting a near repeat of yesterday. In fact, the latest models show storms developing south and west of I-10 corridor in the morning and progressing northeast during the afternoon.
The main concern for today is heavy rain and flash flooding. Scrolling through radar imagery from yesterday, some very impressively high numbers were seen. Instantons rainfall rates of over 8″ per hour occurred a few times…that’s 1 inch of rain in 7-8 minutes. While it’s quite rare for a rate that high could be maintained for very long, multiple places did see 4″ over an entire hour yesterday. In addition, it’s not too unlikely that a pattern like this can produce upwards of 5 to 6 inches over an hour. Location is everything though and where the training of these intense storms to occur will determine if flash flooding develops.
The upper level pattern doesn’t appear to change going into Tuesday. The area will continue to sit in a region of weakness between 2 areas of high-pressure with ample moisture in place. The pattern will finally starting to gradually change Wednesday onward. The high-pressure centered near the 4 Corners region of the country will begin to deepen and expand eastward. This will increase subsidence and bring in drier air into the column. Rain chances will slowly decrease as this transition takes place with precip chances possibly as low as 20 to 30 percent on Friday. Of course, lower precip chances along with plenty of sunshine and compressional heating will lead to very hot temperatures.