There is a MARGINAL RISK of severe weather for the entire viewing area mid-afternoon to evening.
Although we are strongly capped currently, cap should erode somewhat this afternoon as weak short wave skims by.
Also, remnant MCV (from severe storms in Iowa & Nebraska lastnight) nearby & a couple outflow boundaries will be around to serve as triggers for some storms with a rather deep layer if CAPE & steepening lapse rate.
Another remant (from the central Plains) will pop storms down towards St. Louis once cap weakens & is breached.
Any storms should diminish rapidly after sunset.
Again, there is the risk of a couple severe storms with a wind/hail threat.
I put rainfall coverage at an average of 30%.
Highs will run 87-90 with heat indices 92-101.
MARGINAL RISK is up for northern half of area for Friday.
I think you could paint this for the north Thursday & Friday (see in second & third images).
On Thursday, one MCS overnight to the morning will traverse Minnesota to Wisconsin, Iowa & northern Illinois.
Its gust front/outflow boundary & diffuse, remnant outflow boundary from some storms later today in the area will result in some storms popping Thursday afternoon & evening.
Storms may battle a bit of capping at first, then overcome it.
There is the risk of a couple severe storms with a wind/hail risk.
I kept rainfall coverage averaging 30%.
Highs will run 88-91 with heat indices 96-102.
On Thursday night, a large MCS should track from the Dakotas, Minnesota & Wisconsin to northern Illinois, then collapse.
However, its outflow boudary will surge southward, reaching our area by Friday morning.
Friday's capping looks especially strong, but this boundary could still serve as a trigger for at least a couple of storms.
I kept the coverage at 20%.
Highs will run 89-92 with heat indices 97-104.
An MCS will likely track from northern Minnesota, through Wisconsin, Michigan & Ontario Friday night-Saturday morning.
Its outflow boundary will reach our area Saturday afternoon.
We do look to become increasingly capped, but an isolated storm or two may pop on that diffuse boundary given up to 3000 J/kg of deep layer CAPE.
It will be hot, humid & windy with highs 90-93 with heat indices 99-107.
I kept the coverage at 20%.
Sunday & Monday look strongly capped with MCSs tracking from the Dakotas to Ontario.
I went for highs Sunday at 90-93 with heat indices 99-107 & 90-95 Monday with 99-108 heat indices. Both Sunday & Monday look to have less wind than the 30 mph gusts of Saturday (gusts to 20 mph instead).
TUESDAY, JULY 2-WEDNESDAY-JULY 3:
Tuesday, an MCV may penetrate nearby out of Minnesota, Wisconsin & far northeastern Iowa, resulting in a trigger for some storms with 30% coverage. Isolated severe risk will exist given very high CAPE & some local enhancement of shear via the MCV. Highs of 90-95 are likely with heat indices 99-108.
As for Wednesday, highs of 89-93 are likely, but the potential is there for very high dew points to pool ahead of an approaching weak cold front. With dew points potential up to 75-78, heat indices may reach 100 to 110.
Late afternoon-evening scattered storms are likely along & ahead of the weak cold front.
The storms will tend to be pulsey in nature with isolated severe risk. Risk of a wet downburst(s) & isolated large hail are possible given the very unstable airmass.
Lack of really good dynamics & shear will prevent widespread severe threat. They pulsey storms may briefly congeal into a couple of gusting-out line segments, but will tend to be multi-cellular with brief intense cores.
THURSDAY, JULY 4-FRIDAY, JULY 5:
At this point, July 4 still looks good. With the cold front stalling over southern Indiana, that is where storms will tend to fire.
Here, it just looks like some fair weather cumulus clouds with high cirrus clouds in mainly the southern half of the sky.
Dew points look to drop from 75-78 to 62-66 over much of the area.
As a lake breeze front comes into northern Newton & Jasper counties, dew points there may drop to 58-62.
So, it does look to feel a bit better Thursday with a north wind at 10 mph.
Highs should run 80-85 with perhaps staying at 76-78 in northern Newton & Jasper counties.
After 57-64 Thursday night, it will begin to heat back up Friday with highs 83-88 with dew points back at 63-67 as light to calm winds for part of the day then turn to the southwest.
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