Summary: Precipitation should be all snow overnight and there may be some significant accumulations by morning. During the day on Wednesday, the precipitation will continue to fall moderate at times into the afternoon. Temperatures look to remain very close to freezing from the ground up to about 10,000 feet so precipitation type during the day is somewhat uncertain. However, a significant change with yesterdays forecast is that I think that it will be a little warmer at the surface. Therefore, there is less risk for freezing rain or icing, even over the elevated terrain and this now looks predominantly like a snow and rain event. At this time of year, this is likely to be an “elevation” event with significant differences in snow accumulation depending on your elevation.

The snow that falls overnight tonight should be “wet” snow with temperatures close to freezing. Therefore, the snow will tend to melt when it hits the road, particularly if the roads are treated. Still, snow will fall moderate to heavy at times after midnight into the early morning, permitting snow to accumulate on the roads faster than it can melt, causing snow-covered or slush-covered roads at times, right into the morning “rush” hour. When it is not snowing heavily overnight, the roads may just be wet in the lower elevations but still probably snow covered over the elevated terrain. During the day, wether it is snowing or raining, the rising temperatures near the surface and the high sun-angle should turn the roads wet over the course of the day.

The time line for this precipitation event looks like this:

Snow should develop from south to north across the county, beginning near midnight, possibly an hour or two before midnight. Snow should fall fairly steadily after midnight, moderate to even heavy at times til morning. The snow may mix with and begin to change to rain in the lower elevations of South County by 6 or 7 am. Likely total snowfall accumulations by morning 3-6″ with the lower amounts most likely in the lower elevations to the north and the higher amounts most likely in the higher elevations in central and southern portions of the county. During the morning hours, wet snow will likely mix with and change to rain between 7 and 10 am in the lower elevations. It is likely to take longer to transition to rain in the elevated terrain where it may stay wet snow until noon in northern areas. There is still a chance that it could remain wet snow for the entire event over the elevated terrain in central and northern Berkshire. Daytime snow accumulations are difficult to predict due to the uncertainty and timing of the changeover to rain. However, in the lower elevations, snow accumulations are unlikely to total more than an additional coating to an inch or so during the morning given the rising temperatures and sun-angle. However, additional snowfall totals during the day in the elevated terrain could range between 1-4″ depending on elevation and when or if the snow changes over (highest totals will most likely be in the north-e.g. Savoy, Florida). Keep in mind that the accumulations during the day are likely to be mostly on grassy surfaces. Also, even though if you total the amounts I have predicted you would come up with as much as 10″ over the elevated terrain, there will not be that much on the ground. Snowfall totals are compiled each hour and there will be considerable melting going on as the snow falls during the day.

Precipitation will begin to taper off during the mid to late afternoon. Any precipitation will change back to all snow during Wednesday evening. However, there should be nothing more than a little light snow or snow showers overnight Wednesday with nothing more than an additional inch or so of accumulation. The should be some snow showers on Thursday as well as the upper-level cold pool moves over the region and destabilizes the atmosphere. Once again, not much accumulation is expected.

Tuesday Night

Overcast with snow developing from south to north between 10 pm and midnight. Snow moderate to even heavy at times after midnight. Probability of precipitation 100%. Most likely snowfall accumulations 3-6″. The snow may begin to mix with or change to rain in the lower elevations in South County toward daybreak.

Low temperatures near 30 to the low 30s in most locations with high 20s over the elevated terrain.

Easterly winds at 5-10 mph in the evening, increasing overnight to 15-25 mph by morning. There will likely be gusts over 30 mph, particularly over the elevated terrain.

Wednesday

Wet snow early, mixing with and changing to rain in the lower elevations during the morning (~7-10am), later (late morning-noon, if at all) over the elevated terrain. Probability of precipitation 100%. Likely additional snowfall accumulation a coating-1″ over the lower elevations, 1-4″ over the elevated terrain

High temperatures in the mid to upper 30s in Pittsfield, Adams, North Adams and Williamstown, near 40 in Great Barrington and Sheffield, and low to mid 30s in the elevated terrain and hilltowns.

Easterly winds at 15-25 mph, diminishing during the afternoon, dropping to 5-10 mph by evening.

Wednesday Night

Overcast with occasional rain or snow showers in the evening, scattered snow showers after midnight. Probability of precipitation 60%. Most likely snowfall accumulation 1″ or less.

Low temperatures in the low 30s in most locations, near 30 over the elevated terrain.

Light east-southeasterly winds.

Thursday

Overcast with scattered snow showers, particularly during the afternoon. Snow may be mixed with rain in the lower elevations. Probability of precipitation 60%. Most likely snowfall accumulations 1″ or less.

High temperatures in the mid to upper 30s in Pittsfield, Adams, North Adams and Williamstown, near 40 in Great Barrington and Sheffield, and low to mid 30s in the elevated terrain and hilltowns.

Light east-southeasterly winds in the morning shifting to northwesterly at 5-10 mph in the afternoon.