SUMMER MARCHES ON...
Before I get into the forecast, I came across a graphic on the Iowa Mesonet (Daryl Herzmann has an excellent site there) which allows us to visualize the highest and lowest hourly temperature readings for any hour of the day. I ran both ends of the spectrum (highest and lowest) for Cedar Rapids and the Quad Cities and came up with this side by side comparison. The hour of the day is on the left and the date of the highest or coldest temperature for that hour is off to the right.
The Quad Cities data goes back to 1929. The all time lowest of 33 below was reported at 7:00 am January 31, 2019. I remember it like it was yesterday! The all-time highest 110 at 3,4, and 5:00 pm July 14, 1936.
For Cedar Rapids the available data only goes back to 1972 so it does not include the heat records established in 1936.
Also, some of you weather junkies may know that the record low in Cedar Rapids is actually 30 below in 2019 and the all-time high in the Quad Cities is 111 in 1936. The reason the graphic does not reflect that is due to the fact the hourly observation was taken at the top of the hour. The temperature was either warmer or colder at some other point within that 60 minute period.
Out of all of the hourly highs and lows, I think the 93 degree reading in both the Quad Cities and Cedar Rapids at 5:00 in the morning is the most eye opening of the bunch. That is a ridiculous temperature for that hour of the day!
Well, there was nothing overly remarkable about Tuesday's weather. The most notable aspect was the temperatures which held in the 70s and low 80s thanks to clouds and in spots rain. Here's the late day readings.
As you can see the those temperatures were only a couple degrees down from Monday so we've had ourselves a nice respite from Saturday's torrid heat.
The one feature that remains an issue is humidity. Dew points were again in the low 70s so the muggies were there even with the blow normal temperatures.
On the satellite, clouds and an approaching cool front were readily apparent as of late Tuesday afternoon.
In most places only light rain occurred. However, as expected a few bands/pockets of heavier rain developed, especially in the south. The Cedar Rapids airport on the south side of town had .88" but amounts on the north side were only .05" or less. Here are the Doppler rainfall estimates.
With the weak front well to the east Wednesday, a couple days of relatively comfortable weather is expected. Highs should generally be in the range of 80-85 through Friday. Humidity will be moderate, about what you would expect in the middle of summer. Rain chances look low as well.
Over the weekend, the heat dome expands again out of the Plains sending another short but intense burst of heat into the central Midwest. On the nose of the heat some thunderstorms are possible Saturday. By Sunday very warm and sticky conditions are back in place and the stage is set for heat advisories on a widespread basis. The GFS is showing dew points in the 80s but I suspect the numbers are a bit inflated. I could certainly see upper 70s and that would be enough to put heat index values into the 103-108 degree category.
Here's the 500mb upper air pattern that drives Sunday's heat
Tuesday a strong short wave is digging into the lakes bringing a cold front and a quick death to the heat Monday. Some storms are also possible Sunday night or Monday, depending on the timing of the front and some mesoscale features yet to be determined.
Meantime, aside from some patchy early morning fog, hump day looks to be nice and friendly around the region. Thanks for visiting and roll weather...TS
