qg_omega

Yup 26 inches of snow with 60 mph winds, awful

12z EPS for Dec08 and Dec12: Blocking in Greenland is not wildly off, however the PNA domain was very wrong which changes everything. Instead of having a PV under the block, it is now over Western Canada and the SE ridge is able to link up to the blocking. This is exactly what I was concerned about on November 27th: SSTs support the -PNA regime and I have no faith in any ensemble trying to break down the -PNA.

DT as well

January looks like a torch

Blocking incoming:

Brutal cold is north of Montana and locked up

yes, nothing like that this month with the PV in BC.

As I have said for the past month, ensembles have extremely low skill past 10 days and should not be used to forecast. The current pattern makes it even more difficult to use them. Look at the EPS forecast from 0z for +84: https://www.tropicaltidbits.com/analysis/models/eps/2022120500/eps_z500a_namer_15.png Compared to the EPS forecast for the same period but + 192 + 252 https://www.tropicaltidbits.com/analysis/models/eps/2022113012/eps_z500a_namer_33.png + 252 https://www.tropicaltidbits.com/analysis/models/eps/2022112800/eps_z500a_namer_43.png The PV is not caught under the block as forecasted but instead is heading into BC with a much stronger -PNA. Also the ridging is connected from the SE into Greenland resulting in a warm cutter pattern. Exactly as I warned a few weeks ago, you need the pattern shifts to move forward in time and just because the NAO is negative, doesn't mean much if a pacific airmass is trapped under the block, even for NNE.

Always take the cold, always

The EPS has been atrocious, especially on the PAC forecast

In this pattern with short wave lengths and lots of blocking, I would suspect correlation coefficients near 0.2 or worse in 10 to 15 day ensemble range. Would easily bet on an opposite look of that today

Can’t imagine anyone doing good in the next three weeks, the pattern screams rain to Maine. There is no cold air under the block and the PV is gone. One of the worst patterns we have seen in December in many many years. Hard to get 5 straight rain events in NNE in December but that’s on deck

10 to 15 day ensembles have no skill, the 10 to 15 day ensemble mean looked good two weeks ago as does today’s….as I said many times statistically it is worse than a coin flip

Yes north of Montreal, rain’s to the greens

No chances in the next three weeks

EPS is consistent in showing a massive linked ridge from the gulf coast into Greenland

Lots of people pointed out the issues weeks ago

Massive block means little when it links up with the SE ridge and strong negative PNA. It’s very possible we link up the ridges and can go very above normal for the second half of December

I said this two weeks ago

Looks above normal again for the month

Power out in armonk with trees down

Carbon copy fella