Chicago Storm

DVN still gusting 58kts currently. Severe winds are lasting a bit longer than the usual hit and go. There was a report that the severe winds lasted for ~45mins in CID.

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SPC needs to consider high with 20z out look or sooner. This is as about as high end as it gets. .

These high end reports continue to be right near the main vortex... .

1255 PM TSTM WND GST 1 S MIDWAY 42.09N 91.70W 08/10/2020 M112 MPH LINN IA EMERGENCY MNGR

1258 PM TSTM WND DMG 4 ENE SHELLSBURG 42.12N 91.81W 08/10/2020 LINN IA EMERGENCY MNGR ESTIMATED GUSTS OVER 100 MPH WITH MULTIPLE CAMPERS BLOWN OVER, ALONG WITH THE SHELTER ROOF AT THE PARK BLOWN OFF.

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1151 AM TSTM WND DMG 2 S MARSHALLTOWN 42.01N 92.91W 08/10/2020 MARSHALL IA STORM CHASER SEVERAL LARGE SECTIONS OF ROOFS BLOWN OFF BUILDINGS ALONG OLD HIGHWAY 30 ON SOUTH PART OF MARSHALLTOWN.

And "hurricane force".

High risk worthy derecho in progress.

****. .

DSM on north to Fort Dodge about to get rocked... .

With you, you never know. .

Not even. Should be E or ESE until it’s around here. .

That SPC outlook still needs some work. .

And we are on track. Gonna need a large moderate risk across Much of IA/S WI/N IL/N-C IN/SW MI. .

While most guidance has been tame for today (Monday), the HRRR and HRRRx develop a fast moving MCS/bow that sweeps across IA/IL/IN this morning into this evening. Digging into things a bit deeper, while the HRRR has been overzealous and alone on an island numerous times this spring and summer, the solution it spits out is actually fairly plausible in this case. The main trough and wave is currently diving into the Northern Plains from Canada, and along with it is a solid jet streak. This can all be seen very nicely on water vapor and IR satellite currently. There’s also a very nice power-keg environment out across portions of SD/NE/MN/IA currently as well, where initial development is expected within the next several hours. 4k+ cape, PWATS of 1.50”+, DP’s in the 70’s, a great EML with ML lapse rates ~9C, 50kts shear and the main wave and jet streak moving in. Should likely see development as the HRRR shows in SD and possibly NE within the next several hours, as capping erodes. The environment mentioned above is supportive of MCS formation, and a damaging wind threat. Now I won’t go as far as saying the derecho the HRRR/HRRRx have is going to occur across IA/IL/IN, but the setup is definitely supportive of something that could be quite good, as long as everything works out. Along the lines of everything working out...One potential caveat is the activity around MSP currently...Does it slowly fade away as it continues to drift east, or does it develop a nice cold pool and drive more SE, which would greatly affect the threat for some downstream areas outlined in this post. .

You're my favorite...Because whatever you say, the opposite happens.

93 ORD (22), 90 MDW (18) and 92 here (20) today. .

89’d at ORD today, and here as well. .

Yep. ENS ditched the -PNA beyond mid-week. .

Looks warm and wet. .

Warmest Julys On Record: 1. 81.3 - 1955 2. 81.2 - 1921 3. 81.1 - 2012 4. 79.2 - 2020 5. 79.0 - 2011 6. 78.5 - 1977 6. 78.5 - 1916 8. 78.4 - 1999 9. 78.3 - 1966 10. 77.8 - 1949

Today has been the worst day of the summer.

Looks like we’ll see a return to a warm/hot and humid pattern beginning Fri/Sat. A nice prolonged -PNA looks to return once again. .