"Snacks between meals" (winter wx 1/21-1/31)

[Thundersnow]

Based on discussions I'm reading, Saturday night and Sunday could be interesting.  There may be sufficient energy behind the front in the cold air to squeeze out some accumulations... even "convective" snow showers.

The NAM model is apparently hinting at this.

[Coach B]

T'snow, I have been wondering about that.  Remember the day following the big snow bust last year we had some snow showers that laid down 1/2 to 1" all across middle Tennessee.  Best I remember, it was not forcast at all.  Nearly all the school systems were closed that Monday as well.  Not a big snow by any means, but enough to get the job done.  

Louisville had this to say about the potential for Sun in yesterdays PM AFD:

SREF IS SHOWING 850MB TEMPS OF NEAR -16C
 SETTLING SWD INTO THE CWA...ALMOST 2 STD DEV BELOW NORMAL FOR LATE
 JANUARY. THIS WILL HELP STEEPEN LAPSE RATES IN THE LOW LEVELS...AND
 LATEST FCST SOUNDINGS FROM NAM AND GFS ARE INDICATING A VERY
 FAVORABLE ENVIRONMENT FOR SNOW SHOWERS SUNDAY AFTN (NAM FCST AT LEX
 HAS 50J/KG CAPE AT 22Z/SUN). WILL INCREASE POPS INTO THE 30-40%
 RANGE SUNDAY FOR SHSN. THREAT MAY CONTINUE INTO SUNDAY NIGHT.
 LOCALIZED ACCUMULATIONS OF AN INCH OR SO ARE CERTAINLY POSSIBLE

[Ron_Jarrell]

Not much to work with per GEM:

[snowdog]

12z GFS and NAM both still have us getting a little something this weekend.  It will be a good start for next weeks "big one".

[Crockett]

One of you guys who knows more about this than I do:

The 12z run of the GFS and the NAM seem to me to show almost all of Saturday night/Sunday's precip as snow behind the colder air, with very little moisture in front of the colder air. Would that be a correct assessment?

[Thundersnow]

Yeah, I think in this clipper type scenario, most of the energy/moisture/height falls are behind the front in the colder air.

[Ron_Jarrell]

One of you guys who knows more about this than I do:

The 12z run of the GFS and the NAM seem to me to show almost all of Saturday night/Sunday's precip as snow behind the colder air, with very little moisture in front of the colder air. Would that be a correct assessment?

Very little rain before the changeover. 850mb will be below freezing at onset, and 2m temps will get there quickly. Of course plateau and northern tier will see changeover quicker with precip onset if it doesn't start as snow. Not too much QPF right now though. GFS MOS showing only about .09 LE.

[Ron_Jarrell]

Here's the link again for GFS txt MOS for BNA: http://beta.wxcaster.com/text/1DegGFS/GFS_Kbna.txt

[Reneezelle]

So give me a guess here, how much do you think we may see? Sounds to me if the moisture is all behind the cold air, thats good right?

[joemomma]

Those of us on the plateau are eagerly awaiting some of the good stuff....

[Reneezelle]

Well? Whats the twelve say???!!!

[snowdog]

Here is the 12z GEM.  Looks like a dusting to an inch possible.  

[Eric]

Hey snowdog, looking at the precip map, the color blue over us translates to 1" precip.  Does the model factor in the ratio for snow (10:1)?

[snowdog]

The way I read it (and I am not even close to being a Met) is we could see about 1-2.5(mm) or total precip over the 12 over period shown.  I think we could see 2 or 3 mm of total frozen precip with this event.  Which would be about .07-.1 total inches.  With a 10:1 ratio that would give about .7-1" of snow.

[Eric]

My bad, I didn't see the mm on the legend.