December and a Hint of January Pattern Discussion

[snow.]

Did any of those periods lead to snowy weather eventually?

 

They all had late season snow except maybe 1957?...not sure about that year

[snow.]

Yeah, it's starting to look good for you! All the top analogs coming up now are very familiar years we've spoke about, with day 8-14 number 1 being 1996!!

 

Very solid way to end November with the December forecast you issued.

 

http://www.cpc.ncep.noaa.gov/products/predictions/814day/analog.php

 

Thanks...hopefully we'll get some blocking at some point

[usedtobe]

Models are extremely similar with the pattern at 8-10 days...which is a B- for cold and a D for snow....

 

I think maybe a c for cold and D for snow during that time frame.

[usedtobe]

I suppose so Wes.  I wasn't throwing off on anyone.  It's just that a few days back everyone was giddy at how good the first half of December looked, and now the enthusiasm seems to be gone.  If a good looking pattern possibility can vanish in a few days, so can a bad looking pattern possibility.

I don't look out much more that 14 days, I think that is about the time period where you can make reasonable guesses about the pattern and the mean temps during that week but not the individual days but I could be full of hubris.  Personally, I never liked that pattern for snow. 

[mattie g]

We suck.

Bring on spring!

[Bob Chill]

I don't look out much more that 14 days, I think that is about the time period where you can make reasonable guesses about the pattern and the mean temps during that week but not the individual days but I could be full of hubris.  Personally, I never liked that pattern for snow. 

 

d11-15 on both the gfs and euro ens show cold breaking off and sliding east at times and the mean trough axis shifting more towards the middle of the country. 

 

The pattern doesn't look "cold" but not warm either. There's a lode of very cold air in western canada and modified pieces will come eastward...in the wake of cutters...to cool us down. 

 

Much is up in the air still. There is plenty of spread. But getting a favorable pattern for snow is a bit of an uphill climb either way. 

[aldie 22]

What happens if tomorrow's ensembles and super duper d+89 ensembles show an A+ pattern?

[Bob Chill]

What happens if tomorrow's ensembles and super duper d+89 ensembles show an A+ pattern?

 

We revel in a weenie celebration of epic proportions. 

[HighStakes]

Did any of those periods lead to snowy weather eventually?

I would guess that 12/02/2005 was the only date that had snow of any significance during the following ten days.

[Bob Chill]

Pretty incredible cold invading the northern plains on the 18z gfs. I know it's an extreme solution but there are 30-40 degree negative departures all the way to TX. The Dakota's would have sub-zero highs if it verified. Even without being in our back yards, an arctic blast like that is very impressive. Would love to see it happen.

[snow.]

Pretty incredible cold invading the northern plains on the 18z gfs. I know it's an extreme solution but there are 30-40 degree negative departures all the way to TX. The Dakota's would have sub-zero highs if it verified. Even without being in our back yards, an arctic blast like that is very impressive. Would love to see it happen.

 

 bouts of short-lived epic cold wouldn't surprise me....I said in some thread yesterday that I think there is the potential in December for a  -15 to -20 departure day....but I think it would be along the lines of 56, 45, 24, 31, 49, so in the 5 day period you are -7 or so on the maxes....and we know we suck at mins, so it would probably be a -5 period...and there is always a counterfeit midnight high in there....so you get the idea....I think we might get blocking later this month, but who knows what the state of the PAC will be...but then at least we can get our 2-3" front thump...

[Heisy]

Said it in the NE thread, but if we can hopefully get that west ridge to shift east a bit the pattern reminds of Jan 94....to my amateur eye at least.

[Bob Chill]

 bouts of short-lived epic cold wouldn't surprise me....I said in some thread yesterday that I think there is the potential in December for a  -15 to -20 departure day....but I think it would be along the lines of 56, 45, 24, 31, 49, so in the 5 day period you are -7 or so on the maxes....and we know we suck at mins, so it would probably be a -5 period...and there is always a counterfeit midnight high in there....so you get the idea....I think we might get blocking later this month, but who knows what the state of the PAC will be...but then at least we can get our 2-3" front thump...

 

This is definitely a "new" pattern compared to many recent ones (good and bad). The blocking thing is a real thorn of course. It's starkly evident on the 18z gfs as the big cold high from the weekend just cruises out to sea as the next system moves in. Just a transient 50/50 would give us a fair chance on the 2nd/3rd storm. But it is what it is.

 

If we aren't going to have blocking, let the hounds dive into the northern and central plains. Maybe we get lucky and end up on the winning side of the gradient. We will get tastes of that cold. And IF a big invasion blasts down through the middle of the country it can definitely help our chances in an overall hostile snow pattern. 

[uncle W]

They all had late season snow except maybe 1957?...not sure about that year

DCA got 2.2" in March and 0.1" in April...probably 3/1/57 and 4/7/57?...1956-57 had a cold and snowy January in DC...

[Amped]

I think maybe a c for cold and D for snow during that time frame.

 

It's an A pattern for cold,  just not in our half of the country.

[CoastalWx]

The first week of December definitely had a relaxation period modeled for a while now. Don't forget that the Aleutian ridge modeled adds the caveat of a -PNA and we know what that can mean for the MA. We had this discussion in our subforum because a few got disappointed for week 1 in December.

[HM]

Did any of those periods lead to snowy weather eventually?

Nothing that you would be impressed with. However, if you are looking for just snow, we still need to watch mid Dec before xmas. As the flow retrogrades, a weak NAO signal may show up and amplification in Plains. If we have enough EPO cold lingering, could make for a messy event. Heck, maybe it will be more frozen than wet, idk. But latest guidance is getting more retrograded later in Dec, so warmth will be trying to take over.

[alwaysready126]

Thank God its only 11/26.  First week of January, we may be singing a different tune.

[mitchnick]

Thank God its only 11/26.  First week of January, we may be singing a different tune.

I think if you look back right after Christmas last year, there were many posts saying the same thing and we know where that got us in the end

we need to be greedy when it comes to snow around here because it's so rare

[snow.]

The first week of December definitely had a relaxation period modeled for a while now. Don't forget that the Aleutian ridge modeled adds the caveat of a -PNA and we know what that can mean for the MA. We had this discussion in our subforum because a few got disappointed for week 1 in December.

 

I was talking with Will about a week ago and mentioned I thought there would be 2-3 days of + departures the 1st week of december....He agreed...

[snow.]

models aren't that warm that 1st week of december..reallt depends where  the gradient sets up...we could be mid to upper 40s much of the week....though  I think a day or 2 of mid 50s or warmer is possibly in the cards

[WxUSAF]

models aren't that warm that 1st week of december..reallt depends where  the gradient sets up...we could be mid to upper 40s much of the week....though  I think a day or 2 of mid 50s or warmer is possibly in the cards

Yeah, looks pretty seasonal overall.  SE ridge might stay beat down, which leaves us with some stale cold air.  Not a snowy looking pattern for sure.  But, I still think as long as our source region is staying in the deep freeze, that bodes well going forward.  

[Bob Chill]

models aren't that warm that 1st week of december..reallt depends where  the gradient sets up...we could be mid to upper 40s much of the week....though  I think a day or 2 of mid 50s or warmer is possibly in the cards

 

 

Yea, pretty much. If a sizeable system develops and cuts we could have a day or 2 of strong sw flow pretty easily. Depends how much the trough out west digs. Not much to get in the way of heights rising in the east. That's for sure. 

[Bob Chill]

Still active in the storm dept on the gfs. 2 lows do the tx - va track. Rain verbatim and the pattern favors a nw track but a mangled mess is still trackable..... long ways off.

[usedtobe]

Just looking at the D+11 Centered mean and compositing the temps for the centered day (Dec 7) and the equivalent of Dec 8th would argue for Matt's day or two possibly getting into the mid 50s> the pattern is really cold out west and some eventually seeps into the area after Dec 9th according to dumb guys extrap of the pattern (always risky).  Anyway here are the two composites.  All 5 days between Dec and Dec 9 average a little above normal with the two warmest days in the composite being the two I'm showing. 

 

 

 

 

The ensembles I looked at from last night showed lots of variation (spread) which usually argues for toning down any extreme forecasts towards climo.  If I were to guess I'd guess the 5 days would average a few degrees above normal but not with much confidence. 

[lsukev]

Still active in the storm dept on the gfs. 2 lows do the tx - va track. Rain verbatim and the pattern favors a nw track but a mangled mess is still trackable..... long ways off.

 

Agreed.  At least it isn't eons of sunny skies   

[WxUSAF]

12z GEFS mean still shows a western trough post Day 7 or so.  Only notable change I've seen from the last few runs is that after Day 10, the lowest heights in the Northern hemisphere are on our side of the pole with the PV set up near Baffin Island.  Still probably a seasonable pattern more or less for us with warm days ahead of any big cutter as Matt and Bob have suggested.  If we can get a low to go past and bomb out to our north, that might be enough to sag the gradient to our south and suppress the flow for a couple days and allow a second low to pass underneath us.  That's not indicated in the model explicitly of course, but is a feasible scenario that could get us a little snow out of this pattern.  

[Bob Chill]

12z GEFS mean still shows a western trough post Day 7 or so.  Only notable change I've seen from the last few runs is that after Day 10, the lowest heights in the Northern hemisphere are on our side of the pole with the PV set up near Baffin Island.  Still probably a seasonable pattern more or less for us with warm days ahead of any big cutter as Matt and Bob have suggested.  If we can get a low to go past and bomb out to our north, that might be enough to sag the gradient to our south and suppress the flow for a couple days and allow a second low to pass underneath us.  That's not indicated in the model explicitly of course, but is a feasible scenario that could get us a little snow out of this pattern.  

 

Pretty much in a nutshell. 

 

Some good agreement with the global ens that we will have a relaxed period next week when the trough digs in the west. After that it will depend on whether the mean trough axis shifts east or not. Euro and gfs are a bit apart here. Last nights euro ens h5 anom mean is centered further west than the gfs. Nothing tragic or exciting in our parts. Seasonable weather verbatim.

 

GEFS is a bit more agressive moving things along. I suppose it's fair to side with the gefs to some extent considering the euro's usual bias hanging things out west.

 

Even though I hyped up the 1st week of Dec pattern when it looked better, without atlantic help expectations should always stay in check. There were plenty of caveats even though it looked good. I was just hoping we could time something into a cold antecedent airmass. That possibility is still there down the road a piece but it's a challenge in these parts so medium to short leads will have to sort that out if anything arises. 

 

At the very least we should all take some solace in the fact that there is no big stable craptastic pattern showing up. This helps us a lot in the sense that there is less time and work involved transitioning into something decent. 

[WxUSAF]

 

 

At the very least we should all take some solace in the fact that there is no big stable craptastic pattern showing up. This helps us a lot in the sense that there is less time and work involved transitioning into something decent. 

Absolutely.  Still better than the last 2 years in that regard.  And our source region is icy cold.  Both of those facts improve our odds over those years, even if the odds overall remain not great.  

[lsukev]

Anyone see the low pressure to the east of us at hour 162 on the Euro?  Temps are marginal (upper 30's) and precip looks limited at this point, but there is a nice high pressure over New England.  Something to watch?

 

Edit: Is that a subtropical system?