Chicago Storm

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. .

No, that’s not what that means. 150 years worth of December days is 4,650 days. If only 77 December days during that 150 years have hit 60°+, only an extremely small amount of December days actually get into the 60°’s. .

Might be about time to break out some stats today. .

ready2torch. .

GFS has a bomb in the N Plains next week. .

he lives. .