Chicago Storm

enlighten us on what this means. .

Definitely, across E NE/MN/IA. .

went back to check the lists, and that indeed was the lone omission and error. .

They are. However, the list of 60+ days is much longer, thus only the top of the count was included. Then 2021 was added in at the bottom of that list just to show we already chalked up 1 60+ day already this month.

Chicago daily records... 12/15 Record High: 64 - 1971 Record High Min: 44 - 1928 12/16 Record High: 60 - 1984

Stats time... Days With 60+ High Temp In December: 9 - 1982 5 - 1998 4 - 1946 4 - 1877 3 - 1984 3 - 1975 3 - 1962 3 - 1951 3 - 1879 1 - 2021 Days With 65+ High Temp In December: 3 - 1975 2 - 1998 2 - 1982 2 - 1970 1 - 2017 1 - 2012 1 - 2001 1 - 1984 1 - 1980 1 - 1951 1 - 1877 1 - 1875 Days With 70+ High Temp In December: 1 - 2012 1 - 1982 1 - 1970 Warmest December Days: 71 - 12/2/1982 71 - 12/3/1970 70 - 12/3/2012 69 - 12/28/1984 68 - 12/5/2001 68 - 12/1/1970 68 - 12/31/1875 67 - 12/3/1998 67 - 12/13/1975 67 - 12/20/1877 Warmest Met Winter Days: 75 - 2/27/1976 72 - 2/25/2000 71 - 12/2/1982 71 - 12/3/1970 70 - 2/20/2017 70 - 2/18/2017 70 - 12/3/2012 70 - 2/11/1999 69 - 2/19/2017 69 - 12/28/1984 69 - 2/15/1954 68 - 2/22/2017 68 - 12/5/2001 68 - 12/1/1970 68 - 2/22/1922 68 - 12/31/1875

keeping my inbox full ftw. .

A little more on this now… As I mentioned a few days ago, we will be transitioning to a new pattern late this week into next weekend. This pattern will continue a -PNA, and will introduce a neutral to - EPO/AO/NAO. At face value, this ‘should’ bring more cold and snow opportunities across more of the sub-forum. Obviously any particular threat within this new pattern will rely on how much of a dip that the EPO/AO/NAO is taking at any particular time. .

Making it to Friday (17th) is a lock, but beyond that it’ll likely become fairly dicey. .

As of this time I haven’t seen anything below EF-2, but obviously it’s still early. .

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Either way there will be a wind/tornado threat, whether activity is cellular or QLCS.

CC signature with it. .

Outside of the sub-forum, but nice example of a slowly maturing supercell in a high shear environment, near Little Rock. .

Denver finally picked up their first measurable snow of the season today. Poor Matty wasn’t even there for it.

If you believe the HRRR, there will be a fairly significant threat into the LOT CWA now as well. .

Another aspect to watch is the synoptic high wind potential. Should have 45-60MPH wind gusts potential across IL/IN/MI/OH. .

18z NAM not to HRRR extent, but getting close. .

If the 18z HRRR has any clue on the severe threat tomorrow… .

Severe weather threat looking possible up into the LOT CWA now. .

that was me about a day or so ago. here's the updated one...

The next pattern shift looking likely to occur next weekend (Weekend of 18/19th).

The Euro continues to look the most significant severe weather wise, even well up into IL/IN. .

Let’s talk December 70°’s… They’re very rare, only having happened three times on record. In addition, it has never been achieved after December 3rd. 71° - 12/2/1982 71° - 12/3/1970 70° - 12/3/2012 Note: There has never been a 70°+ temp in winter between 12/4 and 2/10.

tth is the preferred answer. .