Mid-January Chances

[Ron_Jarrell]

Check out the blocking high over AK. That would be the reason for tracking the storm south and also cause the PV to shunt cold air into the Eastern U.S.

[Thundersnow]

Interesting!

One thing for sure... all the potential ingredients seem to be there.  It's just a matter of whether they will come together at the right time.

[snowdog]

00z Euro showing a suppressed solution.

06z GFS showing 2 potentials back to back.  The first looks like all rain then snow backside the second one looks like a little rain to start then mostly snow. 

At least there is something to look forward too.  The second low at 288hr is intriguing because the cold air would be better entrenched.

Links below to 06z run (1/4/08)
First low (216hr frontside): http://raleighwx.easternuswx.com/models/gfs/06zgfs850mbTSLPp12216.gif
(228hr backside)  http://raleighwx.easternuswx.com/models/gfs/06zgfs850mbTSLPp12228.gif

Second low (276hr)  http://raleighwx.easternuswx.com/models/gfs/06zgfs850mbTSLPp12276.gif
(288hr): http://raleighwx.easternuswx.com/models/gfs/06zgfs850mbTSLPp12288.gif 

[servocrow]

Does it seem that the cold air is digging further down more consistently (at least in model solutions) than it did last year?  And earlier?

They even had flurries in FL this week..not unheard of, but indeed unusual.  Some of that cold air looks to even reach Mexico as well.

[snowdog]

This far out it isnt unusal for the GFS to overestimate the cold (reaching down well into Mexico).  Our current cold shot was pretty impressive though, as you said made it all the way down to Florida.  Which is pretty common in January.  I would like to get into a cold pattern like we had last year Mid Jan through Feb...we just couldnt get a good storm to save our life last year and we had plenty of cold air to work with.   

[servocrow]

True...our dry pattern started VERY early last year.  Lord willing, that WILL NOT repeat this year.

And WE ARE DUE for a snow-wallopin'.

really.

[Ron_Jarrell]

Here's a reality check for you. I've been pulling up state climo reports for JFM 1999. The reason I wanted to look at 99 is because this years LaNina pattern strongly correlates to 99's La Nina. Recent SST Anom suggests warming in 1-2 and cooling in ENSO 3-4 suggesting La Nina is peaking attm. Very similar to the SST anom from 99.

Here's what I found: 1999 saw a brief cold snap the first week of January followed by a lasting warmup. During that brief cold period, Nashville got an inch of snow on the ground with other locales picking up a few inches. The snow was short lived though, and temps returned to above normal throughout the rest of Jan and Feb. The next snow wasn't until mid March (March 15 to be exact) where BNA picked up 1" and that closed our season out. Also noted was much above normal precip for the end of January where Nashville received over 2" of rain of course.

I believe with La Nina we will see an active pattern, but it will be dominated by the PAC jet giving us above normal temps the rest of this winter. Along with the active pattern in above normal temps comes rain. I believe we will see that as well in abundance toward the end of the month. The reason behind 99's March snow is I believe a tendency for our area to see snows when ENSO is near neutral or with slight to moderate ENSO events. With La Nina waning, we saw a snow out of it in 99. If Nina wanes again this year, it would be late in the season, but possibly still early enough to see a cold period that we could see a snow out of in early to mid March.

It is important to note that the Atlantic environment is different from 99's, so variables are at play there. I believe that the primary influence with the NAO in this pattern would be a return to average precip and not directly influence our temps as much.

[Thundersnow]

The 12Z GFS today has trended to a much colder solution for January 12 and beyond.  But, the January 13-14th storm is mainly to our south... in fact, Birmingham and Atlanta might be game for something! (while we would only get light stuff and flurries).

This thing is FAR from set in stone.  It may be fun to watch in the coming days.

[Snowman]

Thats actually where I prefer us to be this far out. It gives this storm time to make a northwest trend. I dont like being in the bullseye 7-10 days out. It will be the cold air im sure. Will it get here in time? Will it stay here? Those are my questions right now. I am not too excited until about 4-5 days out. So I shall be patient for now.

[joemomma]

I'm of the mindset anymore that I don't excited until I see it piling up!  Although from what I'm picking up from you guys, this looks like it could get really exciting.  I noticed that hackuweather has us having another really cold snap in their long-term outlook.

[Thundersnow]

Yes, Snowman, the infamous "northwest trend."

Although, what I have observed that happens is that a storm system will be trended northwest through subsequent model runs, and then it will "correct" further southeast at some point (which may be what we're seeing with this morning's run)... before trending northwest again. 

At this range, the true track of the storm may be somewhere in the middle... it's just hard to say.

[Thundersnow]

Interesting statement from the CPC 8-14 day outlook this afternoon:

8-14 DAY OUTLOOK FOR JAN 12 - 18 2008:  FOR THE WEEK 2 FORECAST PERIOD... THE MAIN UNCERTAINTY IS HOW QUICKLY THE CANADIAN MARITIMES BLOCK WEAKENS AND/OR RETROGRADES.  THE GFS SUPERENSEMBLE, AS WELL AS THE 0Z AND 6Z GFS ENSEMBLE MEANS, SUPPORT AN ANOMALOUS RIDGE WITH THREE MAXIMUM HEIGHT ANOMALY CENTERS... ONE OFF THE PACIFIC NORTHWEST COAST, ANOTHER NEAR HUDSON BAY, AND THE THIRD CENTER SOUTH OF NEWFOUNDLAND.  THESE THREE MODELS ALSO AGREE ON A SIGNIFICANT NEGATIVE HEIGHT ANOMALY CENTER LOCATED OVER THE LOWER MISSISSIPPI VALLEY.  THESE SOLUTIONS FAVOR A RETURN TO COLD, STORMY CONDITIONS FOR MUCH OF THE CENTRAL AND EASTERN CONUS AFTER THE ANTICIPATED BRIEF WARMUP IN EARLY JANUARY. THE OPERATIONAL 0Z AND 6Z GFS ARE FORECASTING AN UNUSUALLY STRONG NORTHEAST PACIFIC RIDGE, AND PULLS THE SOUTH-CENTRAL U.S. TROUGH FURTHER BACK INTO THE SOUTHWEST. THE 0Z GFS ALL BUT ELIMINATES THE CANADIAN MARITIMES RIDGE BY THIS TIME.  TODAYS OFFICIAL 500-HPA HEIGHT FORECAST LEANS MORE TOWARDS THE ENSEMBLE AVERAGES THAN THE SINGLE DETERMINISTIC RUNS.

The 8-14 day map recedes the anomalous warmth in the east and shows an area of below normal temps in the central part of the nation.

Also, it shows a large area of above normal precipitation in much of the central and east.

[Snowman]

In easier terms. Near Normal or slightly below normal temperatures and above normal moisture. I like that scenario.

[Ron_Jarrell]

I like that scenario too. May be our one shot at a decent snow this winter.

[servocrow]

At or below normal temps + above normal precip = BETTER SNOW CHANCES

I like math when it works out that way (like finding money in your coat pocket from last year).