Heat and humidity has been very noticeable so far this weekend, but that's about to change as we head into Sunday.
We've been in a predominantly southwest flow for much of the week that is on the fringe of an area of high pressure pumping in heat to the west. This high-pressure system will begin to break down some by Sunday allowing a more northwesterly flow to develop and surround the Quad Cities. This means we'll get a temporary break from the heat and humidity with temperatures cooling off into the 80s and heat index values quite close to the actual temperature. The active storm track will also take a break and move more to the southwest keeping us dry through at least Tuesday morning.
All good things must come to an end though and they certainly will by the time we reach Tuesday afternoon. Winds will switch back to the southwest ahead of an approaching cold front. This will send high temperatures back into the upper 80s and heat index values well into the 90s as the humidity creeps back up.
Chances for showers and thunderstorms will be primarily centered around two-time frames, one being late Tuesday afternoon and especially Tuesday evening as the front approaches. It appears we'll have enough instability present for a few isolated severe storms, but weak winds aloft won't promote widespread severe storms. The second round arrives for Wednesday morning as the actual front itself clears the area. Some locally heavy downpours will be likely with this activity, but widespread, heavy rainfall is not looking likely.
Once the front moves through, Wednesday evening through Friday will be enjoyable again with dry conditions and low humidity.
By next weekend you'll notice the return of heat and humidity again, along with a storm chance or two.
Meteorologist Andrew Stutzke