CheeselandSkies

Yesterday Day 4 outlook was talking about warm front with primary threat over southern WI. Last 2 NAM runs have like zero EHI north of about I-64 in IL. Ironically, after the GFS was the most progressive solution by far the last couple days, the 18Z actually retrogrades the low center a bit from 21Z Sunday to 00Z Monday. Even so, the warm sector environment isn't very impressive up north along the triple point/WF, mucked up by widespread ongoing convection at 00Z Monday. Moreover, it seems this system has trended sort of disjointed, with the SFC low still forecast in a favorable position for a S WI/N IL tornado threat, but the main 500mb jet now forecast much further south, with the speed max/left exit region being over SW IN/KY. This is why they shouldn't bother getting too cute with these outlooks in July/August.

Yeah looks like massive amounts of rain wrecks the instability.

Good write-up from LOT:

...and 0Z NAM now flipped to progressive solution with warm sector into central/even southern IN by 00Z Monday. Sayonara.

18Z GFS might be the start of the cave, finally has the low along the MS River at 00Z Monday. Environment still doesn't look super impressive, though* (at least not over nearly as widespread an area as the Day 4 highlight). Seems like the trough comes out a bit positively tilted with most of the flow hanging on the back side. Meanwhile, 12Z NAM had the sfc low center over northern WI at 00Z Monday; 18Z has it over the IA/MO/IL confluence, but at about the same longitude. Lots yet to be sorted out. *No doubt due in large part to the massive amount of convection the model breaks out.

GFS is still vastly more progressive than the other models. Latest (06Z) run has the low over Milwaukee at 18Z Sunday, while 06Z NAM has it west of Mason City, IA at that time (as far out as it goes). 00Z Euro (can't see 06Z on free Pivotal) has it pretty much right over Mason City. Again this does seem to be a known bias of the GFS, so not surprising SPC is siding with other guidance. Euro also deepens the low 2MB from 18Z Sunday to 00Z Monday...

Also, 5 days in a row with a SLGT+ highlight from SPC. August > May.

Uncanny.

Latest NAM has the low over La Crosse at 12Z Sunday, still might be mistimed for us. If it was there at 00Z Monday... Edit: On that run, eastern Iowa and possibly parts of western IL look interesting on Saturday evening. SPC highlight for that day has been much further west.

Wonder when the GFS will cave. Today's 12Z still has the action in Lower MI/NW OH at 00Z Monday, although it does seem a tad bit further west with the low than previous runs.

ENSO impact on severe is really hard to gauge. For example the Super Nino December of 2015 had two major tornado outbreaks in four days (12/23 MS/TN, 12/26 TX); but December 2021 (Nina, I'm sure) had two massive ones as well. December 1, 2018 (weak Nina IIRC) also featured an unusually far north and prolific outbreak in Illinois.

The GFS is just way, way more progressive, with the 18Z having the low over southwest Lower Michigan at 00Z Monday. However it does seem to have a bias for this sort of thing, so we shall see. 12Z Euro OTOH is almost classic SW flow, >60kt strongly diffluent jet, left exit region over S WI/N IL. Looks like it belongs in May.

Sucks, but thankfully it's mostly going to my northeast. Looks like WI north of a line from Manitowoc northwest, and most of MI, NE 1/2 of OH, northern WV, and western PA are getting it.

SPC mentions it, too (Saturday Day5 highlight for NE/w IA is pretty gutsy in August IMO). 06Z GFS has any potential for Sunday way east of us.

View from my porch as the action rolled in last night. Constant lightning flashes, but no visible bolts.

Quality.

Had some interesting colors/effects with the sunset last night before the storms rolled in.

Another QLCS spinup possible near Eagle, WI.

New tornado warning, multiple QLCS spinups possible along here.

SVR finally extended through Dane.

Sauk County sup just went TOR.

https://www.spc.noaa.gov/products/md/md1763.html

Nice comma head near Friendship while embedded sup moves toward Baraboo.

Entire region getting rocked and we haven't even seen a flicker of lightning in Madison yet...looks like the HRRR was kinda right. That northern complex should at least clip us, though.