It was just enough of a wind shift that permitted some drier air to slip into some portions of central Indiana Tuesday. 100-degree heat indices return area wide this week
DEW POINT DROPPED
Dropping the dew point makes the difference. Front slipped south last night and lowered humidity on a northeast breeze. Indianapolis did not reach 90-degrees and the HEAT INDEX Tuesday was much lower and much more comfortable in Indianapolis by as much as 10-degrees. It peaked at 102° Monday.
It is easy to find where front has stalled, Terre Haute was still feeling like it was over 100° late it the day. The overnight temperatures will still be warm but at least a little more comfortable through sunrise. Winds are to gradually shift again overnight to the southwest, signaling a return of high levels of heat and humidity for Wednesday afternoon.
DOME OF HEAT TO EXPAND – WARNINGS ISSUED
That stalled front just south of Indianapolis, returns north Wednesday as a warm front bringing resurgent heat and humidity. Temperatures are to rise and surpass Monday’s high of the season of 93° reaching a predicted high of 94°. That is just shy of the 1936 record for the date of 96°. Thursday is also predicted to be the hottest in the spell reaching 97° and shy of the 1936 record for the date of 98°. Each afternoon will produce a heat index over 100° and likely well over 100° Thursday.
With a triple-digit heat index forecast that high Wednesday and again Thursday afternoons, an excessive heat warning has been issued from 8am Wednesday to midnight Thursday night.
Our default weather pattern of the summer is coming back, the ‘Northwest Flow’ jet stream backs down and allows the massive upper-air high (Hot dome) to expand east. This will likely send the heat index to well over 100° each of the next two afternoons.
Relief is still days away but it is coming. Starting this weekend milder air returns!