Wednesday-Friday
The Saint John Valley will experience a substantial temperature change during the second half of the workweek, beginning with cool, generally pleasant conditions Wednesday before a surge of milder air arrives Thursday. A cold front will then bring a return to cooler and somewhat unsettled weather Friday.
High pressure will maintain mostly sunny skies Wednesday as the colder Canadian air mass established earlier in the week gradually moderates. Light southwest winds will accompany afternoon temperatures in the middle 40s. Mostly clear skies Wednesday night will allow temperatures to fall into the lower 30s, with locally colder readings possible in sheltered sections of the Saint John and Fish River valleys.
Thursday will be considerably warmer as strengthening southwest winds transport milder air into northern Maine ahead of an approaching cold front. Temperatures will climb into the lower 60s, making Thursday the warmest day of the forecast period. Winds may gust to around 25 mph, particularly across exposed terrain. Increasing cloud cover Thursday evening will accompany a 50% chance of light rain overnight. Rainfall amounts should remain limited, generally less than one-tenth of an inch.
The frontal system will bring cooler conditions Friday, although afternoon temperatures should still reach the lower 50s. Partly sunny skies will alternate with cloudier periods, accompanied by a 50% chance of light rain. Westerly winds will remain noticeable during the day before shifting toward the northwest. Any lingering showers should end Friday evening, followed by clearing skies and a considerably colder night as temperatures fall into the middle 20s.
Saturday-Tuesday
A cooler Canadian air mass will settle across northern Maine Saturday as high pressure builds behind the departing frontal system. Sunshine will return throughout the Saint John Valley, although afternoon temperatures will remain in the lower 40s. Northwest winds may still add to the chill, particularly in exposed locations. Clear skies Saturday night will favor substantial cooling, with temperatures falling into the lower 20s and locally colder conditions possible in sheltered valleys.
Sunday will bring a modest improvement as high pressure maintains generally sunny conditions and temperatures recover into the upper 40s. The lighter winds and sunshine should provide favorable weather for outdoor activities, although another chilly night is expected, with temperatures near freezing.
The settled pattern should continue Monday, with partly sunny skies and afternoon temperatures around 50°F. Partly cloudy skies Monday night will allow temperatures to return to the upper 20s.
By Tuesday, somewhat cooler conditions will return, with mostly sunny skies and afternoon temperatures in the middle 40s. A weak disturbance may approach northern Maine Tuesday evening, introducing a slight chance of precipitation overnight. However, the timing and coverage remain uncertain. With temperatures expected to fall into the middle 20s, precipitation type could become a consideration if moisture reaches the Valley, although the current forecast indicates only a slight chance of rain.
Looking Ahead: November 4-10
The Climate Prediction Center’s October 27 outlook favors above-normal temperatures across northern Maine and the Saint John Valley, with precipitation probabilities also leaning above normal. A developing trough across the eastern United States may support a more active weather pattern, bringing additional opportunities for precipitation during early November. Typical temperatures across the Valley during this period feature daytime highs in the lower 40s and overnight lows in the middle to upper 20s.
Daily Forecast Summary
Wednesday: Mostly sunny early, becoming partly sunny. Highs in the middle 40s. Southwest winds 5-10 mph.
Wednesday Night: Mostly clear, with lows in the lower 30s. Southwest winds 5-10 mph.
Thursday: Mostly sunny early, becoming partly sunny and considerably milder. Highs in the lower 60s. Southwest winds 10-15 mph, gusting to 25 mph.
Thursday Night: Mostly cloudy, with a 50% chance of light rain. Lows in the middle 40s. Southwest winds 10-15 mph, gusting to 25 mph.
Friday: Partly sunny, with a 50% chance of rain. Highs in the lower 50s. West winds 10-15 mph.
Friday Night: A 50% chance of rain during the evening, then becoming mostly clear. Colder, with lows in the middle 20s.
Saturday: Sunny and cool, with highs in the lower 40s.
Saturday Night: Clear and cold, with lows in the lower 20s.
Sunday: Mostly sunny and somewhat milder, with highs in the upper 40s.
Sunday Night: Mostly clear, with lows in the lower 30s.
Monday: Partly sunny, with highs around 50.
Monday Night: Partly cloudy, with lows in the upper 20s.
Tuesday: Mostly sunny, with highs in the middle 40s.
Tuesday Night: Partly cloudy, with a slight chance of rain after 7 PM. Lows in the middle 20s.
Weather Notice: The weekly forecast, by UMFK Professor Joseph E. Becker, is based on available computer models and data and may not reflect current conditions or later forecast updates. Check The County.me or the National Weather Service Caribou, Maine for the most recent weather information for the Saint John Valley.
