2/14 - 2/15 Valentine's Day Clipper

[Kevin]

Anybody know where I can find the "like" button.........

lol

Unfortunately seems the the 12z Euro shifted the 500 low way north...up near Chicago now...that would not be good for us should it verify...

[Eric]

lol

Unfortunately seems the the 12z Euro shifted the 500 low way north...up near Chicago now...that would not be good for us should it verify...

Hahahaha.....figured it'd be like that.

[Woodvegas]

Haven't seen the 12Z ECMWF today so I can't comment on it yet. The 12Z GFS actually looks better though...

[Tom23]

The normally conservative MRX is calling for a snow event for my area from Sat. Night into Monday night. Have a feeling with the temps that I'll see a mix from Saturday through Sunday afternoon, but I don't know yet. They did say that they'd like to wait a few more days (Thursday night/Friday time range??) to say what will happen with the precip in the weekend.

[Charles L.]

OHX has increased chances to 40% Sunday, 40% Sunday night, and 40% on President's Day.

LMK has increased chances to 60% Sunday, 60% Sunday night, and 40% on President's Day.

 

[Tom23]

Guys I don't understand why MRX is calling for snow over my area for the daytime if the highs are:
Sunday-38
Monday (Pres. Day)-36

[Crockett]

Haven't seen the 12Z ECMWF today so I can't comment on it yet. The 12Z GFS actually looks better though...

Now that is a juicy clipper...

[keithinala]

Guys I don't understand why MRX is calling for snow over my area for the daytime if the highs are:
Sunday-38
Monday (Pres. Day)-36

Just because that is the high doesn't mean that will be the temp if it's snowing. If it's cold enough to support snow up above, it can snow at several degrees above freezing, but most likely it will quickly fall to near freezing when precip starts.

[Tom23]

Oh that makes sense Keithinala. Hope it does happen..

[Eric]

18z GFS shows a low passing directly through the heart of TN (not sure if past runs have shown this feature) with most of the state on the warm side of the low.  Surface temps currently look to warm for frozen precip...850s support it.  There is, however, a pretty good wraparound event pictured as the low progresses northeastward.  18z GFS skew-Ts look decent, though....maybe above freezing for only 800-1000' AGL.  Given the dynamics, if the snow fell hard enough, temps could cool enough aloft to allow for snowfall.  I just don't know if they'll be strong enough...  And we're still a few days out, so PLENTY of time for a change. 

[Kevin]

18z GFS shows a low passing directly through the heart of TN (not sure if past runs have shown this feature) with most of the state on the warm side of the low.  Surface temps currently look to warm for frozen precip...850s support it.  There is, however, a pretty good wraparound event pictured as the low progresses northeastward.  18z GFS skew-Ts look decent, though....maybe above freezing for only 800-1000' AGL.  Given the dynamics, if the snow fell hard enough, temps could cool enough aloft to allow for snowfall.  I just don't know if they'll be strong enough...  And we're still a few days out, so PLENTY of time for a change.  

Personally I think the GFS is doing its typical warm low-level temperature bias when dealing with an arctic front. That said...it could start out as rain before changing over as the arctic front won't have passed through yet...that may take out .05 to .10 of the modeled QPF from the 18z run (of course keeping in mind as you say there is a lot of time for changes...and they should be expected).

The low passing to the north is typical in a clipper system. There's no connection to the STJ so "WAA" is not really an issue...

[Eric]

Personally I think the GFS is doing its typical warm low-level temperature bias when dealing with an arctic front. That said...it could start out as rain before changing over as the arctic front won't have passed through yet...that may take out .05 to .10 of the modeled QPF from the 18z run (of course keeping in mind as you say there is a lot of time for changes...and they should be expected).

I'll keep that in mind.  Did the low that's present on the 18z get spun up by the front's passage?

[Kevin]

I'll keep that in mind.  Did the low that's present on the 18z get spun up by the front's passage?

Yeah...the low spins up to the north upstream of the front...just like a typical frontal system. But...like I mentioned above...clipper systems are usually going to pass near if not north of us anyway...that's just how they behave.

Clippers are very very tricky to forecast because a lot of things can go wrong with them...that can benefit us greatly or leave us all crying...

[Franklin SnowKing]

Hey guys I know it is the JMA and NOGAPS but the 12z runs on those models show up to .5 qpf in the Middle Tennessee area on 2/15. If that verifies and it is all snow it could be fun.

[snowdog]

This is kind of an odd clipper type deal.  It comes down from the northwest and looks to join or spin up a low near BNA...in which it then starts feeding up WAA and most of the state goes above freezing.  There has been some crazy weather of late.  I've never heard of WAA associated with a clipper but hey DC is sitting under 4 feet of snow.