Snow/Cold Outlook Sunday Night(11/9) to Tuesday (11/11)

With the first widespread cold outbreak and Allegheny snow event on the way, scenes like the one below may be experienced Monday-Tuesday

Showers push in on Sunday, as well as colder air through through the p.m hours. Showers will begin to transition to wet flakes and snow shower activity first in the higher Wv areas of the Alleghenies Sunday evening/early night and overnight Sunday snow looks mainly light and across the Wv high ground.

Remember days ago the GFS rushed drier air in on Monday and shut the snow activity off? Well it has since came around to the Euro solution and keeps an unstable NW flow and accompanying secondary front later Monday as potentially the best period of accumulation as we go Monday PM to Tuesday a.m. squalls may be present Monday Pm-Tuesday a.m as well and as you know, those can rapidly cause deteriorating travel. Temps in combination with gusty winds will allow for rapid covering on roadways, especially after nightfall.

With more similarities in modeling now, let’s punch the GFS in motion.

Again, liking the later Monday-Tuesday a.m stretch the best. Many folks will get up Monday expecting to have all the accumulation thats expected to have occured and thats not expected to be the case.

Temps dropping Sunday pm, overnight in to Monday and holding steady Monday. Mainly 20s across the Alleghenies. Any areas of sun, that likely will occur will aid in a potential equally setup. Squally setups, much like thunderstorms, impact localized areas while areas missing out will see lower accumulations. Some of these squalls can make it to and across the east side of the Alleghenies.

Temps Monday night continue to drop in to the teens and low 20s for most of the Alleghenies, the highest Wv tops may drop in to the upper single digit air temps.

A look the 850mb Temps off the 12z GFS. The best method to get an idea of the highest Wv tops. Indicating upper single digits possible. (These numbers are in celcius)

A look at the temps off the 12Z GFS

Winds will be gusty, but not extreme through the period. Strongest winds look likely Monday Night, Tuesday. Gusts 25-35mph+ during the coldest stretch. Winds also do increase as the trough lifts on Wednesday with once again, strong winds. The coldest period in combo with stronger winds will produce windchills 0 to 10 across most of the Alleghenies, with 0 to -10 above higher exposed 4000’+ Elevations.

A look at the wind and windchills off the 12z GFS. Once the mesoscale models come in to range, you’ll see those depict the coldest windchills a bit better vs the GFS.

Now snowfall….Snowfall in these setups have variability and reduction as you progress east in the Alleghenie. . Areas in the eastern Alleghenies can still be impacted by squalls and localized higher amounts.

●In general:

Snowfall amounts(always lean towards the low to mid range of these numbers with a good performance getting the high end) looking like a 2-5″ western Alleghenies. 1-3″ eastern Alleghenies from Garrett, Preston and north in to Pa. As you move in to Wv, favored upslope zones by Tuesday Pm could see pops of 4-8″ with localized higher pops possible. Most areas in the Wv Alleghenies look to be in the 2-5″ range with 1-2″ west of the Alleghenies in the lower elevations.

The Blended Model v5 Par IMO gives a decent outlook. No model will be perfect in a squally and high ratio setup.

I’ll stick to that as I think it gives a range that looks reasonable giving the setup. The very warm lakes, the very early, very cold unstable air mass should produce. Most modeling looks a bit too high on the high end so for now I’ll refrain from killing it with images off all models… oh heck I cant refrain…

keep in mind, multi day accumulation is not the same thing as snowfall depth…..will post updates as needed. Expect some sort of winter weather Advisories issued for areas as we go through the next 24 hour period.

oh yeahhhhh dig it