St. John Valley weather for Dec. 23-29, 2020
Short-Term Outlook: Wednesday – Friday
High pressure will build across the Valley this morning into the afternoon then move east of the region tonight. Meanwhile, low pressure over the Upper Mississippi Valley will move across the Great Lakes tonight and track towards James Bay in Canada Thursday drawing a strong cold front east towards the SJV.
A secondary low pressure will form in the Middle Atlantic and track north along the front Thursday night into Friday as it strengthens. The cold front will cross the Valley Christmas Day with rain along with windy conditions as it traverses the region. The system will fetch moisture and warm air in from the Caribbean with near record highs in the Valley Christmas Day. Valley locations will likely see in excess of 1 inch of rainfall from this Christmas Day storm with the highest totals in southern portions of the region. Rain will continue Friday night before colder air moving in behind the system brings a changeover to snow early Saturday.
Today & Tonight
Partly cloudy to mostly clear in the morning then partly cloudy in the afternoon with a high in the upper 10s/low 20s. Chance for precipitation 5 percent. Northwest winds 10 to 15 mph become southwest in the afternoon at 0 to 5 mph.
Overnight, mostly cloudy with a 30 percent chance for precipitation. Low in the lower 10s with south winds around 0 to 5 mph.
Thursday, Dec. 24 / Christmas Eve
Mostly cloudy in the morning then becoming overcast in the afternoon with a 30 percent chance for snow showers. Less than 1/10-inch expected. High in the low 40s with south winds 10 to 15 mph.
Thursday night, cloudy with a 90 percent chance for rain. Rainfall totals around 1/10-inch expected. Low in the lower 40s with south winds 10 to 15 mph.
Friday, Dec. 25 / Christmas Day
Cloudy with a 100 percent chance for rain. Rainfall totals around 1/2-inch expected. High in the low 50s with southeast winds 15 to 20 mph gusting 30 to 35 mph.
Friday night, cloudy with a 90 percent chance for rain mixing with / changing to snow after midnight. Low in the low 30s. South winds 8 to 14 mph.
Medium-Range: Saturday – Tuesday
Snow/snow showers are expected Saturday into Saturday night. High pressure briefly builds in Sunday and Sunday night with increasing clouds by Monday afternoon as another low-pressure system tracks east from the Great Lakes with a chance for snow Monday night and Tuesday as a cold front moves through.
Saturday, Dec. 26 / Boxing Day (Canada)
Mostly cloudy with a 30 percent chance for snow tapering to snow showers in the afternoon. High in the low 30s with southwest winds 0 to 7 mph.
Saturday night, becoming partly cloudy with a 20 percent chance for scattered snow showers. Low in the mid-10s with west winds 8 to 14 mph.
Sunday, Dec. 27
Partly cloudy with a 5 percent chance for snow showers early. High in the mid-20s with west winds 8 to 14 mph.
Sunday night, partly cloudy with a 5 percent chance for precipitation. Low in the mid-10s with southwest winds 0 to 7 mph.
Monday, Dec. 28
Partly cloudy with a 20 percent chance for scattered snow showers, mainly in the afternoon. High in the low 30s with southeast winds 0 to 7 mph.
Monday night, partly cloudy with a 30 percent chance for snow. Low in the mid-20s with southeast winds 8 to 14 mph.
Tuesday, Dec. 29
Mostly cloudy with a 40 percent chance for snow. High in the low 30s with northeast winds 0 to 7 mph.
Tuesday night, partly cloudy with a 20 percent chance for snow/snow showers. Low in the lower 10s with northwest winds 8 to 14 mph.
Regional Long-Range Trends: Wednesday, Dec.30 – Monday, Jan. 4
Above normal temperatures and precipitation
Note: Computer model precision diminishes the further into the week the forecast projects. Check the Fiddlehead Focus for weather updates with more current information.
The Week Ahead is the work of UMFK Professor Joseph E. Becker based on personal weather station data, various computer forecast models, and information that the National Weather Service, NOAA, and other weather resources provide.