St. John Valley Weather for July 14-20, 2021
Short-Term Outlook: Wednesday – Friday
A warm front moved through overnight ushering in higher dew points and humidity levels. Low-level clouds across the Valley will keep temperatures in the lower 70s today for most Valley locations.
High-resolution models show a line of storms moving into the Allagash from Québec later today bringing a chance for showers and thunderstorms across northern Maine as they track to the east. Any thunderstorms are expected to be sub-severe, though some storms may feature heavy downpours.
Areas of fog are possible overnight with a slight chance for showers Thursday as a cold front slowly approaches from the west. Isolated showers continue overnight into Friday with increasing chances for showers and thunderstorms by the afternoon as the cold front closes in on the region. The front moves through the Valley Friday night with showers waning behind the frontal boundary by early Saturday.
Today & Tonight
Cloudy and more humid with a slight chance for showers in the morning then showers likely in the afternoon with a chance for thunderstorms. Heavy downpours possible in some storms. Chance for precipitation 80percent. Rainfall totals between 0.01and 0.09-inch. High around 73 with south winds 5 to 10 mph.
Tonight, cloudy and humid with showers likely and a chance for thunderstorms in the evening. Chance for precipitation 60 percent. Rainfall totals less than 0.10-inch. Low around 63 with south winds becoming southwest winds 0 to 5 mph.
Thursday, July 15
Partly sunny with a slight chance for showers. Chance for precipitation 20 percent. High around 85 with southwest winds 0 to 5 mph.
Thursday night, partly cloudy with a 20 percent chance for showers. Low around 65 with south winds 0 to 5 mph.
Friday, July 16
Partly sunny in the morning then mostly cloudy in the afternoon with a 60 percent chance for showers and afternoon thunderstorms. Rainfall totals in the 0.10 to 0.25-inch range. High around 80 with southwest winds 5 to 10 shifting to the west in the afternoon.
Friday night, partly cloudy with a 20 percent chance for showers. Low around 58 with west winds 0 to 7 mph.
Medium-Range Outlook: Saturday – Tuesday
High pressure builds in Saturday with lower humidity levels and drier conditions. Low pressure tracking south of the state will bring a slight chance for showers to the SJV Sunday. Partly cloudy skies with a chance for afternoon showers and thunderstorms are expected Monday with partly sunny skies and a chance for mainly afternoon showers and thunderstorms Tuesday as low pressure tracks towards the Valley from the Great Lakes.
Saturday, July 17
Partly sunny with a 20 percent chance for afternoon showers. High near 81 with northwest winds 0 to 7 mph.
Saturday night, partly cloudy with a 20 percent chance for showers. Low around 58 with west winds 0 to 7 mph.
Sunday, July 18
Mostly cloudy with a 20 percent chance for showers. High near 80 with west winds 0 to 7 mph.
Sunday night, mostly cloudy with a 20 percent chance for scattered showers. Low near 58 with west winds 0 to 7 mph.
Monday, July 19
Partly sunny with a 30 percent chance for scattered afternoon showers and thunderstorms. High around 81 with north winds 0 to 7 mph.
Monday night, partly cloudy with a 20 percent chance for isolated showers. Low near 58 with north winds 0 to 7 mph.
Tuesday, July 20
Partly sunny with a slight chance for showers in the morning then a chance for showers and thunderstorms in the afternoon. Chance for precipitation 30 percent. High near 80 with southwest winds 0 to 7 mph.
Tuesday night, mostly cloudy with a 50 percent chance for showers and a chance for isolated thunderstorms. Low around 59 with northwest winds 0 to 7 mph.
Long-Range Trends: Wed. July 21 – Tue. July 27
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.