THERE'S A NEW SHERIFF IN TOWN...
This past weekend saw some exceptional Midwest weather ranging from extreme humidity and heat to torrential rains of up to a foot in NW Illinois. The highly impactful weather was brought about by a monsoonal flow of moisture that brought available water vapor (humidity) to levels greater than 2.50 inches. Very rarely have I seen water vapor level that high that break without excessive rainfall rates and totals. This event was no exception. Heat index values also exceeded 110 degrees in spots with 80 degree dew points.
Actually the event was well forecast. We at TSwails.com nailed the sauna like conditions and heavy rain potential aimed at the north days in advance. Additionally the NWS had heat advisories and flood watches posted in a timely fashion. Flash flood warnings were also issued when the need arose.
These are the PWATS (available water vapor) the EURO depicted three days in advance of the weekend onslaught.
Here you can see the moderate risk outlook issued for excessive rains in my northern counties by the Weather Prediction Center Saturday night and Sunday.
The Storm Prediction Center put this mesoscale discussion out just before flash flooding began in northern Illinois.
These are NWS reports showing where flooding was eventually observed.
The rainfall graphic shows much of my are north of I-80 picked up 3-6 inches of rain Saturday night through Sunday night with local amounts up to 8 inches.
Below you can clearly identify the 10 inch plus bullseye between Dubuque and Rockford where significant flash flooding occurred.
In the wink of an eye Monday the rains ended, the humidity lessened and temperatures tanked. Look at these late afternoon readings Monday that were in the low to mid 70s. Dew points had also lowered by 15 degrees thanks to a fresh NW wind. What a dramatic and welcome change.
THERE'S A NEW SHERIF IN TOWN...
Today, there's a new sheriff in town, one who commands peaceful, quiet, law abiding weather. There will be no more wild hot weather mischief while he's running the show and from the looks of things he's going to be in charge through the remainder of the work week. The locals call him " Sheriff High Pressure"
Anyway, under the dominance of high pressure the forecast looks straight forward and high confidence through Thursday. Skies have already undergone a clearing process Monday night but the clearing skies and residual moisture may create some patchy fog to start the day Tuesday morning. This would be most likely on the north and should depart early leaving the are with sunshine that will give way to scattered cumulus in the afternoon. Similar conditions are likely Wednesday. As for highs, most areas will remain in the upper 70s to lower 80s. Thursday there are signs warmer air will make another push towards the central Midwest. This time the main thrust should remain just to the west but highs are likely to climb a bit going into the weekend.
With the heat close by we then bring the ring of fire back into play. As early as Friday spotty showers and storms may pop up. However, the location is contingent on where the differential heating boundary sets-up. It's still too early to make that call but I will introduce at least a small chance of showers and storms Friday and Saturday. There looks to be plenty of dry hours and this scenario is nothing compared to what we saw this past weekend. Here's what the EURO meteogram looks like for temperatures the next 10 days.
With that, I guess I'm going to round up that new sheriff and see if he's up for a sarsaparilla on me. It's always good to be on the right side of the law. Have a fine day and roll weather....TS