Following a slew of precipitation which coincided with the Tuesday evening commute, a brief lull in the action awaits us this evening as a warm front lifts east/northeastward across the region. After 10pm tonight (between 11PM and 3AM) it is possible to see a few more isolated rain &/or snow showers across the region as the system’s cold front approaches…
For the rest of the overnight period, the best chances for any breaks in the cloud cover appear downwind of the ADK’s (the lower Champlain Valley; parts of S. VT) whereas most of us stay mostly cloudy. Seeing as the low-level air behind this boundary is not all that “dry” (dewpoints still in the 20’s) it will likely take until the late morning to burn off any moisture trapped from this evening’s precipitation. Additionally, orographic effects will also play a role in the amount of sunshine each part of the region sees as well. Temperatures are fairly mild to start, however. Not a whole lot of diurnal range by sunset–especially for areas north and west of the CPV…
Wednesday night will bring slightly chillier low temperatures and set the stage for what could be a complicated start to a larger & wetter system for Thursday afternoon/evening (vs. what we saw tonight). The question currently at hand is: how far north does an approaching warm front make it and what is the timing? Also, there is the question of how much cold air gets locked to the east of the Green Mountains and, perhaps, deeper sheltered valleys of the ADK’s. Should cold air get “locked in” at the surface, we could be dealing with a prolonged period of freezing rain in the aforementioned locations. A large portion of the atmosphere between the 1500′ and 10,000′ will start above freezing which leaves the question of where & when does the warmer air enter at the surface…
Best thought now is: a brief period of freezing rain in the valleys (starting between 1pm-4pm) before a transition to a raw & cold rain (temps 34-36 in the CPV) whereas areas above 1000′ &/or east of the Green Mountains could have a prolonged period of freezing rain resulting in 0.10″-0.25″ of ice accretion. This forecast will need to be monitored very carefully in the coming 24 hours seeing as the temperature profile and complex topography of the region will make it a tricky one for forecasting…
The good news is, this system (again) appears to be relatively “quick-hitting” and should be exiting the region between 8PM and 10PM Thursday evening. The cold front with this system will not be all that “cold”–more of a marked wind shift (south to southwest). Temperatures on Friday will likely be the warmest of the week with some areas approaching the mid-40’s! This precedes a secondary boundary swinging through Friday night which will usher in a brief period of seasonably cold weather for Saturday (upper 20’s/lower-30’s).
Stay tuned for updates!
-Meteorologist Justin Templer
