.SHORT TERM /Tonight through Thursday night/... Issued at 411 AM EDT Tue Mar 20 2018 Main focus is on changeover to snow tonight and snowfall amounts. Models in pretty good agreement and generally used a consensus. Another upper low moves in tonight and keeps the surface low stalled just southeast of the area. This could set up a strong deformation zone over the eastern counties of the forecast area. Temperature profiles indicate a changeover to snow from north to south from around 8 pm to midnight. The best forcing will set up before midnight but likely remain across the eastern counties through much of the overnight. Given the cooler highs today and mostly cloudy skies, road temperatures will start out cooler then last night and cool to below freezing without much trouble. Snowfall rates with the cooler but more saturated profiles and some possible dendritic growth could approach an inch an hour at their height, and thus think 4 inch amounts are possible across some of the eastern counties. With the colder road temps and this bumping up to the morning commute time, impacts and amounts necessitate a winter weather advisory beginning at 8 pm and running through midday Wednesday. Will likely be able to end the advisory a bit earlier than that but including a buffer in case the system slows even more as this has been a trend. This system will finally kick out by Wednesday afternoon and dry conditions will move in. Temperatures will rebound a bit Thursday into the mid 40s to around 50, but more chances for precipitation will arrive in the southwest counties Thursday night as a front approaches. A wintry mix looks possible at onset. && .LONG TERM (Friday through Monday)... Issued at 311 AM EDT Tue Mar 20 2018 Mostly wet weather and below normal temperatures are expected this weekend as Winter refuses to give up without a fight. Models agree that the long term will start off with an upper low over the northeastern states, a high amplitude ridge over the central states and troughing over the west coast. Models also agree, the central ridge will flatten as it moves overhead on Saturday. Meanwhile, energy from the western trough and accompanying frontal system will approach. Models have timing differences with these features along with timing of QPF. So, confidence is not good on timing and thus do not have enough to overturn the blend output which has PoPs starting off Friday afternoon and maximizing Friday overnight through Saturday evening. After that, upper waves in southwest flow aloft could bring more showers to the area. With below normal temperatures, nighttime and morning snow and or wintry mix looks reasonable. Should see just rain during the afternoon hours. Confidence is high on below normal temperatures to start off with. Meanwhile, temperatures closer to normal look good by Monday. However, with model differences, confidence is low.
Winter is still hanging on all week long.
Here's NWS forecast discussion for today and rest of this week.
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