St. John Valley weather, May 17-23, 2023

3-Day Outlook: Wednesday, May 17-Friday, May 19

A cold upper-level trough will move across the area today with mostly cloudy skies, gusty northwest winds, and a chance for isolated snow showers along with some isolated afternoon rain showers. No accumulation is anticipated from this system. 

The upper trough will move east of the Valley tonight with high pressure building in from the Great Lakes. While overnight lows fall into the lower 30s winds are expected in the 10-12 mph range tonight which will likely preclude frost. Partly cloudy skies with isolated snow showers are possible this evening, then skies become mostly clear after midnight. Today’s highs top out in the middle 40s with the lower 30s overnight.

Sunny skies are expected Thursday as high pressure over the Middle Atlantic builds across the St. John Valley. The wind becomes west by afternoon in the 10-15 mph range  with gusts to 25 mph possible. Thursday’s high is expected to be in the upper 50s. Thursday night, mostly clear skies are expected with southwesterly flow developing as the ridge of high pressure moves east. Overnight lows fall into the upper 30s with southwest winds 5-8 mph.

Return flow around the departing high pressure ridge in the Atlantic brings temperatures in the low 70s Friday with partly cloudy skies expected with breezy southwest winds 14-16 mph gusting up to around 28 mph at times. Friday night remains partly cloudy with a chance for an isolated shower after midnight. The low is expected in the mid-40s. 

Daily Summary

Today: Scattered snow showers before noon, then scattered rain and snow showers. Mostly cloudy, with highs mainly in the middle 40s. North wind around 15 mph. Chance of precipitation is 30 percent.

Tonight: A slight chance of rain and snow showers before 7 p.m. Partly cloudy, with lows mostly in the lower 30s. Northwest wind between 10 and 12 mph. Chance of precipitation is 20 percent.

Thursday: Sunny, with highs mainly in the upper 50s. West wind between 10 and 13 mph.

Thursday Night: Partly cloudy, with lows mostly in the upper 30s. West wind around 7 mph.

Friday: Mostly sunny, with highs mainly in the lower 70s. South wind between 14 and 16 mph.

Friday Night: Mostly cloudy, with lows mostly in the middle 40s. South wind between 11 and 15 mph.

4- to 7-day Outlook: Saturday, May 20 -Tuesday, May 23

An upper low and cold front approach from the west Saturday as mostly cloudy skies overspread the area Saturday morning. There will be increasing chances for rain in the afternoon continuing into Saturday night as the low from the west phases with a disturbance moving up the East Coast. Rain is likely overnight into Sunday morning. Highs reach the middle 60s Saturday and lows in the lower 50s Saturday night. South winds expected in the 8-14 mph range.

Cloudy skies with rain are likely Sunday morning into the afternoon before tapering to showers towards evening. Highs reach the upper 60s across much of the Valley with the wind becoming west 8-14 mph. Sunday night, partly cloudy skies develop with a chance for scattered showers. Sunday night’s low is expected in the upper 30s. Northwest winds currently expected in the 8-14 mph range.

An upper-level trough follows the cold front Monday with partly cloudy skies and a chance for isolated showers that taper off by evening. Monday’s high reaches the middle 50s with northwest winds 8-14 mph.  Monday night, skies become mostly clear with a low in the mid-30s with a west wind 0-7 mph expected. A bit early yet to assess the frost potential for Monday night.

Tuesday features mostly sunny skies with a high in the mid-60s. South wind in the 8-14 mph range expected. Tuesday night looks mostly clear to partly cloudy with a low in the middle 40s and a west wind 0-7 mph, based on current forecast model data.

Daily Summary

Saturday: A chance of rain, mainly after 10 a.m. Mostly cloudy, with highs mainly in the middle 60s. South wind between 10 and 14 mph. Chance of precipitation is 40 percent.

Saturday Night: Rain likely. Cloudy, with lows mainly in the lower 50s. Chance of precipitation is 70 percent.

Sunday: Rain likely. Mostly cloudy, with highs mainly in the upper 60s. Chance of precipitation is 60 percent.

Sunday Night: A chance of showers. Partly cloudy, with lows mainly in the upper 30s. Chance of precipitation is 30 percent.

Monday: A slight chance of showers. Mostly sunny, with highs mostly in the middle 50s. Chance of precipitation is 20 percent.

Monday Night: Mostly clear, with lows mostly in the middle 30s.

Tuesday: Mostly sunny, with highs mostly in the middle 60s.

Tuesday Night: Mostly clear to partly cloudy, with lows mostly in the mid-40s.

8- to 14-day Trends: Wednesday, May 24-Tuesday, May 30 

Above normal temperatures / Near normal 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.