Chicago Storm

the derecho was just the start.

That will be a question for @RCNYILWX, as LOT would handle that decision.

12z Euro a tick south and drier. .

I know that Ricky's thoughts were higher.

i refuse to back it a 3rd time, just in case.

i'm still waiting for eurythmics time.

12z GEFS Mean .

next time know what you're talking about first, before trying to claim an lol victory. see above.

12z UKMET bumped north and drier.

channeling your inner angrysummons here. yes, everyone did know the storm was going to shear apart with eastward extent. i'm not sure there is anyone here that didn't believe that. however, the trend for the storm to end up further northwest in the plains due to additional ridging (in part) is not something that was originally modeled...and is part of why it is shearing out faster as it heads east. please share your crystal ball next time.

i'm pretty sure he was before your time.

It was mostly virga.

12z GEM with a solid bump north and drier.

One thing that we have seen change over time is for the storm system to end up further northwest in the Plains, as it ejects out and gets caught in a bit of ridge that extends back up into the Rockies and BC/Alberta. This allows the storm system to peak sooner while out west, before hitting the wall and quickly shearing off to the east.

12z GFS keeping with the trend of going drier.

12z RGEM bumping south and drier.

That has been a large part of it, especially with how much the confluence over the Lakes/Northeast has been changing with time. There have also been some changes with the main southern wave with how far north/south it ejects out, as well as changes with ridging ahead of it. Another thing to watch, is the next trough coming into the West Coast, as that is actually somewhat acting as a kicker for our ejecting southern wave.

There were 3 soundings missing in the Southwestern US, which is significant given that is where the main southern trough/wave is located. At the same time, soundings occurred as normal across most of the rest of the US and Canada, which allowed for the open field ahead of the southern wave and the northern stream to be fully sampled still. So probably have some caution, but don't overthink it too much. Edit: Also, some Mexico soundings were missing at times yesterday, but were available this morning.

12z NAM .

Parts of IA went from 13" 6z run to 0" 12z run.

12z NAM is much drier.

Confluence in S Canada/N Lakes/Northeast is further south and the southern wave ejects out a bit further south.

12z NAM coming in with a big bump south.

Very much has been the case over the years.

probably on point there.