The following forecast is provided by Ryan Mercer as part of lab work for the Introduction to Meteorology course (ATM-145) under faculty (Joe Kravitz) supervision. The forecast discussion is mine (JK) ……

The cold trough in the jet stream wave pattern centered over our region will, finally, lift out and allow warmer air south of the jet stream to work its way in, as a ridge builds over us for Sunday and Monday. Surface high pressure will crest to our south tonight and then begin to move off the coast during the day on Saturday. As a result, we will have fair skies tonight and Saturday, with slightly milder temperatures on Saturday. A weak warm front, extending well to the east from a surface low pressure system in the northern Great Plains will lift slowly through Berkshire County late Saturday afternoon and Saturday night. This will result in occasional light scattered showers. Things could get a little tricky as temperatures will likely be around or just below freezing at the surface over a good part of the county, particularly over the elevated terrain until about midnight, when the front finally pushes through and temperatures rise above freezing. Therefore, the precipitation is likely to be sleet and freezing rain for a time during the evening. Even though temperatures will be close to freezing and the precipitation will be light, the ground is probably below freezing given how cold it has been. Therefore it won’t take much freezing rain to create some slippery spots.

After the front passes, it will be milder on Sunday, with a mix of clouds and sun and temperatures in the 40s. Meanwhile, a stronger surface low pressure system moving north from the Gulf Coast will merge with the one moving east from the Great Plains and move through the Great Lakes Sunday night. This stronger low will drag another warm front through here after midnight Sunday and into Monday morning. We will see a period of heavier rain with this stronger front, on the order of 0.50″, and this precipitation will be all rain, with temperatures well above freezing. After the front passes through on Monday, temperatures will soar to near 60 degrees. 

On Tuesday, the cold front trailing south from the surface low departing into Canada will begin to move slowly east as another amplified trough in the jet stream moves back over us with colder air for Wednesday through Friday. As the cold front moves through on Wednesday, a surface low pressure system will develop along it, off the Mid-Atlantic coast, and move northeastward. The European model has been bringing this low close enough to the coast that we see a few inches of snow here on Wednesday but the U.S. long-range model (GFS) has it further off the coast, so that we don’t get any precipitation. I will update this situation on Monday…….

Friday Night

Mostly clear and cold. 

Low temperatures in the mid teens, low teens over the elevated terrain.

Westerly winds at 5-10 mph this evening, becoming light southwesterly after midnight.

Saturday

Mostly sunny in the morning, increasing cloudiness with the chance of a light sleet or freezing rain shower late. Probability of precipitation 30%. 

High temperatures in the mid 30s in Pittsfield, Lee, Stockbridge, Adams, North Adams, and Williamstown; mid to upper 30s in Great Barrington and Sheffield and; low 30s over the elevated terrain. However, temperatures will fall back to near freezing after sunset.

Southwesterly winds at 5-10 mph.

Saturday Night

Cloudy with occasional, scattered light showers likely. The precipitation should fall as sleet and then freezing rain during the evening and then change to plain rain after midnight. Probability of precipitation 60%. Likely rainfall totals around 0.10″.

Temperatures will be at or just below freezing in the lower elevations before midnight and upper 20s to near 30 over the elevated terrain. Temperatures should rise above freezing everywhere after midnight.

Southwesterly winds at 5-10 mph, becoming light after midnight.

Sunday

A mix of clouds and sun and milder. There is likely to be more clouds than sun to the north and more sun than clouds to the south.

High temperatures in the mid to upper 40s in Pittsfield, Lee and Stockbridge, Adams, North Adams and Williamstown; upper 40s in Great Barrington and Sheffield and; low to mid 40s over the elevated terrain. 

Light southwesterly winds, shifting to southerly in the afternoon.

Sunday Night and Monday

Increasing cloudiness Sunday evening with rain developing just after midnight and continuing into Monday morning. Rain should taper off by mid-morning. Low clouds and some occasional sprinkles and drizzle will likely persist into the afternoon. Overnight lows near 40 will occur in the evening, with temperatures rising through the 40s after midnight. Highs on Monday in the mid to upper 50s.