Latest data from the afternoon computer model runs and what I am seeing in the radar and satellite suggest the snow may be a bit heavier and it looks like a widespread 3-6″ snowfall is likely for the county tomorrow and tomorrow night.

The following are some snowfall totals reported to the NWS office in Albany from the recent storm:

North County: The big “winner” for the county was Savoy at 20.2″; Adams – 12″; Chesire – 12″; and Williamstown – 8″

Central Berkshire: Windsor – 13.4″; Washington – 12″; Stockbridge – 12″; Hinsdale – 10″; Becket – 10″; Pittsfield  – 9″; Lanesboro – 7.5″; Hancock – 4.5″

South County: Otis – 11.5″; Alford – 5.5″

There were a few “mesoscale” (on a scale smaller than the storm itself) phenomena which had a large impact (predominantly diminishing) on snowfall totals for Berkshire County.

1) A “gravity wave” appeared to develop and propagate over the county as the storm intensified rapidly off the Mid-Atlantic Coast Wednesday evening. These phenomena are not uncommon when a coastal storm rapidly intensifies as it moves over the warm waters of the Gulf Stream. However, it is a forecasting dilemma because they do not always develop, and they are a complicated, somewhat poorly understood physical phenomena so they are not manifested in the computer models.

To describe these waves in the most basic form, they are vertically-oriented waves that develop due to rapid ascent in the atmosphere over the intensifying surface low. Buoyancy and gravity are the vertical restoring forces that generate a vertical “oscillation” of air in the atmosphere. Essentially, the air which is accelerating upward “bounces” up and down between two very stable layers, usually inversions (temperatures increase with height instead of decrease) in the atmosphere, 1] the tropopause (transition between the weather layer, the troposphere, and the warmer stratosphere [warmed by ozone absorbing UV light from the sun], at about 30,000 feet altitude) and 2] the lowest 5-10 K feet of the troposphere near the surface where warmer air is being forced up and over colder air near the surface to the north and northeast of the surface low. This results in a “wave” of alternating upward and downward moving air radiating out toward the north/northeast of the surface low. Where the air is going up, the precipitation is enhanced and where it is going down, the precipitation shuts down.

After an initial burst of heavy snow moving south to north across the county in the early evening (upward branch of the gravity wave) the precipitation completely shut down for several hours over the county (downward branch). This is typical of a gravity wave since, apparently, it takes a while to regenerate enough upward motion to redevelop the precipitation after it shuts down from the downward branch of the gravity wave.

2) Downsloping – This occurred as very strong easterly winds forced air up (upward motion=cooling, condensation and heavy precipitation) the eastern highlands and then down (downward motion=warming, evaporation and lighter precipitation) the western slopes into the valleys. This is the reason that elevated terrain in eastern parts of the county (Savoy, Washington, Windsor, Otis, Becket) received much more snow than western portions of the county (Pittsfield, Alford, Williamstown, Hancock).

3) Mixed precipitation – There was a mixing with and brief changeover to sleet and freezing rain in the early morning on Thursday in South County and parts of Central Berkshire.

Summary: We are still along the eastern side of the trough in the jet stream wave pattern, which puts us in the path of the next developing surface low pressure system presently located over Louisiana. However, unlike the last storm, the jet stream wave pattern is more zonally (east-west) oriented so the surface low will not intensify as much and will move through much faster than the last storm, tracking off to our south off the Mid-Atlantic Coast and out to sea Saturday afternoon and evening.

Air is cold at all levels of the atmosphere so this should be an all snow event without concern for any ice or mixed precipitation. Most of the county should receive in the 2-4″ range with some spots in the elevated terrain receiving as much as 5 or 6″. The snow should begin around noon or early afternoon on Saturday. The snow should be generally light but it could be occasionally moderate and continue through the afternoon and evening. The snow will begin to taper off in the later evening but snow showers will likely continue off and on into Sunday morning.

It will become blustery and cold on Sunday with some partial clearing in the afternoon after some morning cloudiness and flurries. Temperatures will remain below normal for the rest of the week as the jet stream shifts to our south. There may be some snow flurries and showers as a cold front moves through on Wednesday, opening the door for a very cold Continental Arctic air mass (our first of the season) to move in for late week with low temperatures near zero and highs not making it out of the teens.

Friday Night

Partly to mostly cloudy and seasonably cold.

Low temperatures in the mid teens in most locations with some low teens over the elevated terrain.

Northwest winds at 5-10 mph, becoming light and then calm after midnight.

Saturday

Becoming overcast early with snow developing around noon or early afternoon. The snow will be generally light but there could be a few bursts of moderate snow. Probability of precipitation 90%. 1-3″ snowfall accumulations are likely by dark.

High temperatures should be in the mid 20s in Pittsfield, Adams, North Adams and Williamstown, mid to upper 20s in Great Barrington and Sheffield, and low 20s over the elevated terrain and hilltowns.

Winds light and variable in the morning, becoming east-northeasterly at 5-10 mph in the afternoon.

Saturday Night

Overcast with intermittent light snow during the evening, tapering to snow showers near midnight. Scattered snow showers should continue off and on into Sunday morning. Probability of precipitation 80%. An additional 1-2″ of snowfall accumulation is likely. Total accumulations will be in the 2-4″ range for most locations, with 5 or 6″ in some spots in the elevated terrain and hilltowns.

Low temperatures near 20 with mid to upper teens over the elevated terrain.

Winds shifting to northwesterly during the evening and increasing to 10-15 mph after midnight.

Sunday

Mostly cloudy with scattered snow flurries during the morning. No accumulation, other than a light dusting in a few places is expected. It will become partly sunny in the afternoon but will be blustery and cold.

Temperatures will not rise much with high temperature in the low 20s in Pittsfield, Adams, North Adams and Williamstown, low to mid 20s in Great Barrington and Sheffield, and mid to upper teens over the elevated terrain and hilltowns.

Northwest winds will increase to 10-20 mph by afternoon and as high as 25 mph over the higher terrain. Gusts from 30 mph in the lower elevations to as high as 40 mph over the higher terrain.

Summary: A fairly deep surface low pressure center located over eastern Kentucky is presently generating heavy snow over the upper Ohio Valley. The surface low is beginning to redevelop along the Mid-Atlantic coast. This is a common occurrence with eastern U.S. winter storms as the most upper-level divergence and upward motion in the atmosphere shifts to the coast, where the greatest temperature contrast is located. The surface low should track to the Delmarva Peninsula by midnight and just south of Long Island by Thursday morning. It will then track over Cape Cod and into the Gulf of Maine during the day Thursday.

The air over the Northeast is cold enough at all levels for the precipitation to begin as snow everywhere. However, the track of the surface low will be right along the coastline and the counterclockwise circulation around the low will bring much milder air from over the ocean (surface water temperatures still in the 40s) northward and westward where it will override the cold air near the surface. This will definitely cause a fairly rapid changeover to ice and eventually rain in areas to our south and east where snow accumulations will not be particularly great.

The precipitation will start as snow in Berkshire County from south to north, at around 5 pm in South County and near 7 pm in North County. Berkshire County will lie right along a transition zone between snow and ice late tonight and tomorrow morning. The farther south and east within the county one is located, the more likely that the snow will change to sleet and, possibly, freezing rain after midnight tonight. The precipitation should stay snow in North County and, there, over a foot of snow is likely to fall.

In South County, a changeover to sleet and, possibly, freezing rain is likely after midnight. However, even there 4-8″ of snow will likely fall before the changeover. An additional 0.50″ to 1″ of sleet and 0.25″ of ice (freezing rain) could fall during the morning hours of Thursday.

Central portions of Berkshire County provide more of a forecast challenge. If there is a changeover, it looks like 6-12″ of snow will likely fall before any changeover to sleet well after midnight. Another 0.50″ of sleet could fall during the early morning hours, with an additional thin coating of ice. This is presently the “party line” (all public forecast outlets are forecasting a changeover). However, my feeling at this point is that it will remain all snow in much of Central Berkshire which would result in an accumulation of over one foot there as well.

The intensity of precipitation will be the heaviest overnight and will begin to taper off during the morning Thursday. It will also become quite windy overnight tonight as the pressure gradient intensifies as the low approaches the county. Winds will peak out of the east-northeast at 20-30 mph with gusts to 40-50 mph after midnight. Gusts to 50-60 mph could occur along east-facing elevated terrain. Winds will begin to weaken toward morning and during the day Thursday. Precipitation will change back to all snow during the afternoon and evening on Thursday as the surface low pulls east and northwest winds bring colder air back in at all levels. We could receive an additional 1-3″ in “backlash” snow showers during this time as the storm moves out.

I expect snowfall totals for the entire storm to be 12-16″ in North County and much of Central Berkshire. Accumulations could be on the order of 16-20″ in some of the favored east-facing slopes along the elevated terrain (e.g. Savoy). Snowfall totals in South County should range from 4-8″ in most locations but up to 10″ if the changeover occurs late. 

It will become partly cloudy and seasonably cold on Friday. A weak storm will move by to our south on Saturday. Right now it looks like only 1-3″ of snow from that system.

I will try to update this forecast later today as more information becomes available…..

Summary: It looks likely that Berkshire County should have a White Christmas as we receive about 1-3″ tonight into tomorrow morning from a weak surface low pressure system passing by to our south. The higher amounts in that range should fall in South County with the lower end of that range more likely in North County. The snow should spread across the county from south to north, starting around 11 pm in South County, midnight in Central Berkshire and around 1 am in North County. The precipitation may start as a burst of moderate snow but, in general, the snow will be light and intermittent. Light snow is still likely at daybreak but it should taper off fairly quickly and end during the late morning hours.

The biggest weather story of the week and probably the season so far will likely be the much stronger storm (Nor’easter) that appears headed our way for Wednesday night and Thursday. The surface low pressure center will move along the western slopes of the Appalachians during the day Wednesday and then redevelop along the Delmarva Peninsula Wednesday evening. It will then move slowly northeastward hugging the New Jersey and Long Island coasts Wednesday night and Thursday morning and then over Cape Cod by Thursday afternoon. The precipitation will begin as snow Wednesday evening and will likely come down heavy at times. With this track, the counterclockwise circulation around the low will also generate strong Northeast winds (i.e. Nor’easter). However, with the track hugging the coastline, this same circulation will cause milder air from the ocean to lift up and over the cold dense air near the surface. This warmer air aloft could cause the precipitation to change to sleet (ice pellets) for a time. This is more likely to occur in southern portions of the county than northern portions. If all snow falls we should be looking at at least 8-12″ and possibly more that a foot. If there is a transition to sleet, this will diminish snowfall amounts considerably. Once any warmer air gets in place aloft, and the sleet begins, the remainder of the precipitation in any location that this occurs will likely continue as sleet. At this point, I think the all snow scenario for most of the county, with a possible changeover to sleet in South County, looks most plausible and I believe we will get substantial accumulations.

After that storm moves by it should turn colder for the remainder of the week and then we could get another coastal storm over the weekend….

Monday Night

Increasing, lowering and thickening clouds this evening with snow developing from south to north near midnight. There may be a brief burst of moderate snow at the outset but the snow will generally be light and intermittent through the remainder of the night. Probability of precipitation 90%. Snowfall totals overnight should range between 0.5″ and 2″.

Temperatures should fall into the mid 20s in the lower elevations and low 20s over the elevated terrain with the onset of the snow and then hold steady for the remainder of the night.

Calm winds this evening will become light (less than 5 mph) out of the north-northeast after midnight.

Tuesday

Intermittent light snow tapering off during the morning and ending by noon. A low overcast should persist for most of the afternoon, although there may be a few breaks in the clouds late. Probability of precipitation 70%. Total snow accumulations for Monday night and Tuesday will likely be 1-3″ with the higher amounts to the south and lower end of the range to the north.

Temperatures will not rise much with highs near 30 to low 30s in Pittsfield, Adams, North Adams and Williamstown, low 30s in Great Barrington and Sheffield, and mid to upper 20s over the elevated terrain and hilltowns.

Northwest winds at 5-10 mph.

Tuesday Night

Clearing skies during the evening, becoming clear after midnight.

We are set up for a fairly good radiational cooling night with clear skies, light winds and a snow cover. However, the winds won’t be completely calm and the snow cover will be thin. Still, it may be the coldest night of the season so far with low temperatures in the low to mid teens.

Light northwesterly winds becoming northerly after midnight.

Wednesday

It will start out mostly sunny but clouds will be increasing, thickening and lowering during the afternoon. There is a slight chance that snow could begin late. Probability of precipitation 20%.

High temperature in the low 30s in Pittsfield, low to mid 30s in Adams, North Adams and Williamstown, mid 30s in Great Barrington and Sheffield, and mid to upper 20s over the elevated terrain and hilltowns.

Light northeast winds early will increase to 8-12 mph by dark.

Wednesday Night and Thursday

Snow will likely develop Wednesday evening and continue moderate to heavy at times through the morning on Thursday. The precipitation likely will change to sleet in South County and possibly in Central Berkshire. However, I think it will more likely stay all snow in Central and Northern Berkshire. It could even stay all snow in the south. The precipitation should change back to all snow and taper off during Thursday afternoon. Probability of precipitation near 100%. Areas where the precipitation stays all snow will likely receive at least 8-12″ and possibly more than a foot, particularly over the favored east-facing slopes over the elevated terrain. Places where it does turn to sleet will likely receive 3-6″ before the transition with an additional inch or so of ice pellets.

Temperatures should hold steady overnight in the mid to upper 20s in the lower elevations and low to mid 20s over the elevated terrain. Temperatures will only rise a few degrees during the day on Thursday. It should remain freezing or below everywhere.

Northeast winds will increase to 15-25 mph overnight Wednesday night, probably higher over the elevated terrain, particularly exposed east-facing slopes. Gusts to 40 mph are likely. During the day on Thursday winds will diminish and shift to northwest during the afternoon.

Just a quick update….I will give a more comprehensive forecast later today.

It now looks like less snow from the low pressure system moving through Christmas Eve night, more on the order of an inch or two, although this should still be enough to create the mood of a White Christmas. Also, more bad news for snow lovers, the bigger storm on Wednesday and Thursday is starting to look more like a mixture of precipitation instead of a big snowstorm as the surface low continues too look like it will track right over western MA. More later….

This forecast is being posted about noontime:

Well, it appears that winter has finally hit Berkshire County. Interestingly, this year astronomical and meteorological winter appear to be aligned, yesterday being the winter solstice. From initial reports it appears that most of the county has received between 1″ and 3″ of snow (although I suspect there were greater amounts in some of the “favored” higher elevations) as lake-effect snow streamers waved over the region this morning. Most of the county is still receiving snow showers although Central Berkshire, including the Pittsfield area, is presently in-between streamers. Lake-effect snow showers will continue off and on for the rest of the day and into this evening but will tend to diminish over time. An additional inch or two could fall in some locations. A particularly heavy band has set up over North County and there an additional 3″ could fall in some of the higher elevations. It will remain quite windy (this cold wind is what is generating the lake-effect in the first place) through this evening and then winds will begin to diminish later tonight and through the day Sunday. Skies will clear somewhat overnight but then it will become mostly cloudy again on Sunday and there is even the chance for additional scattered lake-effect snow showers or flurries although with little if any accumulation. Temperatures will be seasonably cold throughout the weekend.

We will have one relatively tranquil day before the next snow event. It will be mostly sunny Monday morning and then clouds will begin to increase during the afternoon. Snow should begin late Christmas Eve and continue into Christmas morning (White Christmas!). The surface low responsible for this snow now appears a bit more robust and should track just to our south. Most likely accumulations will be 3-6″. Another, stronger storm will move our way for Wednesday evening into Thursday. We could get a foot or more of snow from this storm. The track of the storm in both the U.S. and European long-range models have been along the classic snowstorm path for Berkshire County, off the New Jersey coast and over Cape Cod. However, the GFS model run this morning has the track right over Berkshire which would give us a mixed-bag of frozen precipitation (yuck!). I will watch the trend over the next few days and update the forecast for this potentially large storm in coming days.

The following forecast is provided by Joe Kravitz, the  instructor for the Introduction to Meteorology course:

Summary: After our one nice day today, the storm which is presently giving the upper Midwest a large snowstorm will move through our region tonight and Friday. As with previous storms this year, the surface low pressure center will track to our northwest, leaving us on the warm side of the storm/jet stream. As a result, we will again receive mostly rain, and a fairly substantial amount. This storm, however, is a little different than our previous one. It is much stronger, with a lower central pressure (~980 mb) and, therefore, has a very tight pressure gradient surrounding it. The resulting strong pressure gradient force (PGF) will generate very strong winds. Also, as the surface low drifts by just to our northwest, it will drag its trailing cold front across the region and then slow down and, essentially, stall over northern New England on Friday night and Saturday. The strong, cold, west-northwest winds circulating around the back side of the low will move over the warm, unfrozen Great Lakes, resulting in evaporation of large amounts of moisture and generate large amounts of instability in the atmosphere (warm near the surface/much colder aloft) above the lakes. This will result in considerable upward movement of the moisture laden air that will be enhanced by convergence at the surface as the air reaches the eastern shores of the lakes and surface friction increases (air slams on the brakes and “piles up”). The upward movement will be enhanced even further by the elevated terrain in upstate NY. Upward motion in the atmosphere leads to cooling, condensation (cloud formation) and, eventually, precipitation. The stronger the upward motion, in general, the heavier the precipitation. The last few sentences were a description of how “lake-effect” snow forms and this is shaping up to be a major lake-effect snow event for upstate NY. Some regions will likely receive in excess of a foot of snowfall. Most of this lake moisture will fall as snow before it reaches Berkshire County, however, we will still get some lake-effect snow showers Friday night and Saturday. The lower elevations will likely receive a dusting to 1″ with 1-3″ accumulating over the elevated terrain.

The surface low will weaken considerably over the weekend as it becomes separated from the jet stream and drifts slowly over the Canadian Maritime on Sunday. However, for the first time this season, the jet stream will move south of the region and we will have normal to slightly below normal temperatures for several days. A very weak disturbance passing by to our south on Monday night and Tuesday may give us a little light snow or snow flurries but it does not look like much, if any, accumulating snow at this point. The long-range models are generating a strong surface low pressure system along the East Coast next Thursday but it is too early to tell if this potential storm will impact us and, if so, what type of precipitation we will get.

Thursday Night

Increasing clouds this evening, becoming overcast by late evening. Scattered light snow showers will likely develop near midnight and transition rapidly to sleet and, eventually rain by the early morning hours. No snow accumulation is expected in most locations although there could be a dusting over the elevated terrain before the changeover. Rain will become steadier and heavier toward daybreak. Probability of precipitation near 100%. Rainfall totals between 0.25″ and 0.50″. It will become windy toward morning.

Temperatures rising gradually after midnight to the upper 30s to near 40 in the lower elevations and mid to upper 30s over the elevated terrain.

East-southeast winds at 5-10 mph this evening will increase after midnight, reaching 15-25 mph by daybreak with the stronger wind speeds over the elevated terrain. Gusts to 40 mph, greater over the higher terrain, are possible.

Friday

Rain, heavy at times, through the morning. Rain should end by early afternoon. Probability of precipitation near 100%. Rainfall totals between 0.75″ and 1.00″. There will likely be some breaks in the overcast during the afternoon. It will be quite windy in the morning but winds should die down slightly in the afternoon after the cold front passes. It will be mild in the morning but turn colder during the afternoon.

High temperatures will be late morning to early afternoon, with low 40s in Pittsfield, Adams, North Adams and Williamstown, low to mid 40s in Great Barrington and Sheffield, and upper 30s in the elevated terrain and hilltowns. Temperatures will fall into and through the 30s during the afternoon after the cold front passes in the early afternoon.

East-southeast winds at 15-25 mph, 20-30 mph over the elevated terrain, with gusts between 40 and 50 mph likely in the morning til early afternoon. Winds will then shift to the southwest and decrease somewhat, to 10-20 mph during the afternoon.

Friday Night

Overcast with scattered snow showers developing during the evening, becoming more widespread well after midnight. Probability of precipitation 70%. Snowfall totals for Friday night and Saturday combined will be a dusting to 1″ in the lower elevations and 1-3″ over the elevated terrain and hilltowns.

Temperatures falling into the upper 20s by morning, mid 20s over the elevated terrain.

Southwest winds at 8-12 mph becoming west-northwesterly toward morning.

Saturday

Overcast with scattered snow showers, breezy and colder. Probability of precipitation 70%. Snowfall totals for Friday night and Saturday combined will be a dusting to 1″ in the lower elevations and 1-3″ over the elevated terrain and hilltowns.

Temperatures will not rise much over the course of the day with high temperatures in the low 30s in Pittsfield, low to mid 30s in Adams, North Adams and Williamstown, mid 30s in Great Barrington and Sheffield, and upper 20s in the elevated terrain and hilltowns.

West-northwest winds increasing to 10-20 mph with gusts to 30 mph.

I do not have time to do a complete forecast today due to the open house for the new Hoffman Environmental Center. However, just wanted to note that there now appears to be some “hope” for a white Christmas for Berkshire County. There is the chance for a coating of lake-effect snow Friday night and Saturday and long-range models are now suggesting the development of a weak surface low pressure system that could give us a “light” snowfall on Christmas Eve night. I will update this tomorrow…..

The following forecast is provided by Joe Kravitz, the  instructor for the Introduction to Meteorology course:

Summary: There is little change from yesterday’s forecast. The cold pool aloft (upper-level low pressure), which helped generate the surface low that gave us almost one inch of rainfall overnight, and its associated instability showers (cold aloft, warmer at the surface) are presently moving through central NY state. These showers will loose some of their energy as they rotate through Berkshire County after the “sun” sets. However, most of the county will see some snow showers and/or flurries through the evening and into the early morning hours. The ground is still warm and wet and surface temperatures will be above freezing so not much snow accumulation is expected. In fact, lower elevations will likely see just rain showers at first until the air below cloud level cools enough (evaporation of falling precipitation) to prevent melting of the falling snow. Many places will see a dusting overnight to perhaps 1/2″. The higher elevations could see an inch or two in some locations.

It will turn blustery and colder overnight and through the day on Wednesday, although it will only be “seasonably” cold. There may be a few lingering flurries Wednesday morning. It will be mostly cloudy (predominantly low clouds) for most of the day Wednesday, a typical December day for Berkshire County, as low-level moisture from the Great Lakes (“lake-effect”, as cold air blows over the warmer lakes) is lifted by the Taconic and Hoosac Ranges. It will clear overnight Wednesday as surface high pressure builds in and we will have one nice day on Thursday before a surface low once again tracks to our northwest, bringing us about 0.50″ to 1.00″ of rainfall Thursday night and Friday morning. The passage of the cold front associated with this low will open the door to much colder air over the weekend. There is still some hope for a white Christmas as it appears that the low pressure system may cut-off from the jet stream and stall over the Canadian Maritime region. This will give us a strong, cold northwest flow of air and this will likely generate considerable lake-effect snowfall. Most of the accumulating snow will fall over upstate NY but, as the last stop on the lake-effect train, we could get a few inches as well.

Tuesday Night

Overcast with snow showers and flurries likely this evening into the early morning hours. The precipitation will likely start as rain showers in the lower elevations but be snow everywhere by midnight. Probability of precipitation 70%. Accumulations generally a dusting, to up to 1/2″ in the lower elevations. There could be an inch or even two in some locations over the elevated terrain. It will turn blustery and colder.

Temperatures falling to near 30 by morning, mid to upper 20s in the elevated terrain.

West-northwest winds at 10-15 mph, 15-20 mph over the elevated terrain with gusts between 25 and 30 mph.

Wednesday

Mostly cloudy, breezy and seasonably cold. There is the chance of lingering snow flurries in the morning.

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

Northwest winds at 10-20 mph, 15-25 mph over the elevated terrain, with gusts to near 30 mph.

Wednesday Night

Clearing skies with diminishing winds and seasonably cold temperatures.

Low temperatures in the mid 20s in the lower elevations with low 20s over the elevated terrain.

Northwest winds at 10-15 mph early, becoming light after midnight.

Thursday

Mostly sunny in the morning, increasing high clouds in the afternoon will dim the sun at times.

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

Winds light and variable.

The following forecast is provided by Joe Kravitz, the  instructor for the Introduction to Meteorology course. There is no student forecast today. In fact, the semester has ended so there will be no more student forecasts until I teach the course again next autumn. I will try to post forecasts on my own as many days as possible in the coming months…

Summary: A surface low pressure system, presently located over the Ohio Valley will track northeast to western NY overnight tonight and then redevelop off the New England coast tomorrow before moving rapidly out to sea. As the low tracks to western NY, the counterclockwise flow around the low will force the front, presently stalled over our region, off to our north as a warm front tonight. This will cause temperatures to rise to well above freezing both aloft and at the surface so that any precipitation we receive will be rain. Rain should begin just after midnight and will be moderate at times as it continues into Tuesday morning. Although Berkshire County will receive substantial rainfall from this system, it does not look as robust as it did previously. Rainfall totals should be in the 0.50″ to 1.00″ range. A possible “backlash” of snowfall for the county as cold air moves in behind the departing storm now appears less likely as the storm will be moving east fairly rapidly. We should still get scattered lake enhanced snow flurries and showers Tuesday night but I do not expect any significant accumulations.

It will turn blustery and “cooler” on Wednesday but temperatures will still be slightly above average. We will get some clearing on Wednesday afternoon and into Thursday morning as surface high pressure builds in briefly before our next rainstorm on Thursday night as a surface low and its associated cold front move through. This will set the stage for a colder weekend. Our only hope for a white Christmas now seems to be possible lake-effect snow showers over the weekend.

Monday Night

Overcast with rain developing just after midnight. Rain will fall moderately at times. Probability of precipitation near 100%. Rainfall totals between 0.25″ and 0.50″.

Temperatures will rise slowly, to near 40 in most locations, mid to upper 30s in the elevated terrain, by morning.

Light northeast winds this evening, shifting to easterly and increasing to 10-15 mph after midnight.

Tuesday

Occasional rain and showers early, ending mid morning. Probability of precipitation 80%. Rainfall totals 0.10″ to 0.25″. It will remain mostly cloudy in the afternoon with just a slight chance of a stray shower.

It will be unseasonably mild with high temperatures in mid 40s in Pittsfield, Adams, North Adams and Williamstown, mid to upper 40s in Great Barrington and Sheffield, and low 40s in the elevated terrain and hilltowns.

Easterly winds at 8-12 mph early, will become light and variable midday, and then shift to west-northwesterly at 5-10 mph later in the afternoon.

Tuesday Night

Mostly cloudy, becoming breezy and colder. Scattered snow showers and flurries are likely, particularly during the evening. Probability of precipitation 60%. Snow should accumulate no more than a dusting in most locations although there may be an inch or so in isolated areas of the higher terrain.

Low temperatures near 30 in the lower elevations with mid to upper 20s over the elevated terrain and hilltowns.

Northwest winds increasing to 10-20 mph, 15-25 mph over the elevated terrain. Gusts to 30 mph are likely, particularly in the elevated terrain.

Wednesday

There will be variable amounts of predominantly low clouds, although there should be more clouds than sun. There is still the chance of a few scattered snow flurries. It will be breezy and feel colder, but temperatures will remain above average for mid-December.

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

Northwest winds at 10-20 mph with gusts to near 30 mph.