Monday, January 30, 2012

**February 2-6 Potential Significant Snowfall NEW Discussion**

12z GFS total snowfall
The 12z GFS has taken a turn for the disgusting today. It's looking like the GFS is projecting the storm system to become a separate storm of its own and move north and obliterate the Nebraska, Dakotas region.
As you all know, the +PNA and Strong Phase 6 MJO will be contributing to the eventual track and effects of this storm system. Using those major indices, I think this 12z GFS is garbage. Take a look at the ensembles.

12z GFS ENS Hour 120
12z GFS ENS Hour 132
12z GFS ENS Hour 144
To me, this is a much more acceptable solution. The GFS Ensembles are following a strong +PNA lead, whereas the 12z GFS acts like the jet stream shoots north after curving around the +PNA ridge. A +PNA actually takes the storm along the South and takes it up the East Coast. However, a Phase 6 MJO influences the heaviest precipitation into the Lower Great Lakes and interior Midwest. That would land the jet stream in a format very similar to what these 12z GFS Ensembles are showing.

The ECMWF takes a track that in my eyes looks like it takes a more predominantly +PNA track with maybe a slight MJO influence. Here's the ECMWF vs. the ECMWF Ensembles.

12z ECMWF Hour 120
12z ECMWF ENS Hour 120
The ECMWF Ensembles push the storm further north, but also push the warm air northward as well. In the process, the storm looks to be a tad weaker. However, individual ECMWF ensembles may show something else- we do not have access to those individual members, though.

HPC Day 4 Forecast
HPC Day 5 Forecast
The HPC goes along with the ECMWF/GFS Ensemble groups, much to my liking. Personally, the 12z GFS is one to be thrown out. I don't see that solution per the current trends of the teleconnections.

**A side note: Tonight's 0z model runs and tomorrow's 12z model runs will be ones to watch, as they will contain sampling (observation) data from inside the storm-to-be. You can tell the NOAA is watching this storm, because 12z observation data injected from a storm-to-be winter flight is rare.
By the way, the data is gathered from special airplane flights that drop items that record observations in the atmosphere. these observations are injected into the models and thus help solidify their solutions for those runs in that suite (0z or 12z).

Right now, I do think that the ECMWF/ECMWF ENS are onto something, as is the GFS ENS. I believe that the GFS ENS are banking on a stronger MJO than the ECMWF ENS are, which can be settled as the date for the storm approaches. I am going to go with a ECMWF ENS/GFS ENS blend, as again- group consensus' are better for me than models themselves.
Something I have discovered is that the ECMWF indeed keeps the MJO in Phases 6-7 weaker than the NCEP for the storm timeframe. That said, I think that the stickler for the models will be the MJO strength, as both ensemble groups from the ECMWF/GFS keep the PNA at relatively similar strengths.

I am thinking that the storm will affect the Ohio Valley and take the ECMWF Ensemble direction, where it may eventually hit the Northeast. The NAO will be an interesting piece to watch, as the models are not particularly certain on its fate during the storm.
Any questions may be asked below.



Eddie said...

Could Detroit get snow??

Vlad said...

What impacts could Columbia, MO get from this storm?

Jen from toledo said...

hi andrew....thank you for a in depth is my area, of toledo, ohio going to fair? thanks for all you do

Mike Paulocsak said...

Hi.Andrew.I agree 100% with you about the 12z GFS being garbage!It seems like every run it does projects different snowfall amounts.I admit i don't know much about these models,but the Ensembles would probably be a more certain way to forecast this storm.With that being said,could this possibly bring heavy snow to my area in Ohio.Holme county ohio.Also,thanks a million for sticking up for me the other day!!

Anonymous said...

I don't know. It seems to me that in every storm, the ensembles show colder air and much more snow. Then when the storm comes around, the operation model runs were much more accurate than the ensembles. Hope it changes tomorrow.

Owen12789 said...

Maybe I am looking at this the wrong way but it looks the day five map might give Central Illinois a chance of snow. Am I correct in this assumption. Please correct me if I am wrong.

Joshua Steiner said...

I can see your reasoning quite well, as the National weather Service in Northern Indiana has also thrown out the 12z GFS solution, because of its consistency issues and because of the pattern we are in right now. In my opinion, because of the +PNA and the -NAO/AO, I would expect the storm to take a track a bit further south than what the operational ECMWF is taking, which would result in a storm that would cause snow in the Ohio Valley and Great Lakes (maybe not so much in the Northeast).

Andrew said...

Eddie: Right now, it doesn't look like it.

Vlad: It depends on the track. The ensembles say some form of precipitation, i believe.

Jen: It depends on the track. Right now, you may get some precipitation.

Mike: The amount of cold air will determine the snowfall, if any, and if this verifies. I won't let commenters be harassed on my blog.

Anonymous: I guess time will tell.

Owen: This particular snow map is not showing anything, but we haven't checked out any others recently.

Joshua: The MJO favors the lower great lakes for precipitation in Phase 6. Seeing that it will be a strong phase 6, i think it could be forced north. Also, the NAO looks to be around neutral, therefore lowering the influence of it against a strong +PNA and strong MJO.

Maine man said...

Hi Andrew, First time on blog.I'm from Maine and I wonder do you talk about or give a forecast for this area at all? You talk about a hard area to forecast--this it here in northern New England. I am impressed with your forecast for the ohio valley area and all your information in the other areas also.

Anonymous said...

could nyc get some snow out of this sytem

roadruner said...

When is the Kansas City area going to get in the act. We have had no rain or snow we are a kindel box. FIRE DANGER IS ssoo high need snow rain freez rain any thing fast now.

ERN WX said...

Good post friend. It is going to be a tough call. The models are doing dreadful with this storm. I wonder if this is the pattern changing storm you talked about. I myself am fond about the idea of a pattern changing storm. Have you looked at the MONSTROUS storm on the 12z GFS? It is a wonderful storm for the northeast. Thanks for the work you do.

Anonymous said...

Hey Andrew I saw in the sidebar that you have an IQ Test. I have realized that you are very smart over the time I have followed the blog, and I was wondering what you scored on the test.

Andrew said...

Maine Man: Thanks for stopping by! I have a feeling that in the coming weeks the Northeast will be a focus point for forecasting.

Anonymous: A lithe too far out to tell.

Roadruner: Kansas City is certainly going to have to be watched with this form carefully.

Eastern WX: Let's hope this is it.

Anonymous #2: That is a sponsor type thing that has to be there. I forgot to put that disclaimer up. Sorry for the confusion!