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The slow-moving system responsible for Thursday’s widespread rain will remain close enough to keep Fort Kent and the Saint John Valley cool and unsettled through Saturday. Although the surface low is moving into the Maritimes, the associated upper-level disturbance will depart more slowly, maintaining considerable cloud cover and scattered showers. Lingering moisture from Thursday’s rain will also support areas of morning fog today, locally dense in spots. Colder air aloft may help showers become more numerous this afternoon, with an isolated thunderstorm possible.

Conditions should gradually improve Saturday as the upper-level system moves farther east and somewhat drier air reaches northern Maine. Scattered showers will remain possible, especially earlier in the day, but should decrease with time. For the latter part of the holiday weekend, Sunday is shaping up to be the more favorable day for outdoor plans, as high pressure brings much drier and brighter weather with seasonable temperatures and mostly sunny to partly cloudy skies.

Friday: Areas of fog, locally dense early this morning, will gradually lift, leaving considerable cloud cover across Fort Kent and the Saint John Valley. Scattered showers should become more numerous this afternoon as the atmosphere destabilizes beneath the lingering upper low, and an isolated thunderstorm is possible. Highs should reach the mid- to upper 60s, with winds becoming northerly around 5–10 mph. Showers become less numerous this evening but remain possible overnight beneath mostly cloudy skies. Lows should fall into the lower 50s, with patchy fog possible where winds become light.

Saturday: The lingering upper-level low will make for another cool and somewhat unsettled day, although conditions should gradually improve. Mostly cloudy skies and scattered showers are most likely during the morning and early afternoon before coverage decreases later in the day. Highs should remain in the lower to mid-60s, with northeast winds becoming noticeable. Saturday night turns drier as the system pulls farther away, with skies becoming partly cloudy and temperatures falling into the mid- to upper 40s.

Sunday: A much-improved end to the weekend is expected as the upper low moves farther into the Maritimes and high pressure becomes more influential across northern Maine. Skies should become mostly sunny to partly cloudy, with dry conditions and highs in the mid- to upper 60s. Sunday night should remain mostly clear and cool, with lows generally in the lower to mid-40s. Patchy Saint John River valley fog may develop late where winds become light.

Mon. Sep. 7 - Thu. Sep. 10

A quiet and warmer start to the period is expected as high pressure settles across northern Maine, providing sunny, dry, and pleasant weather for Labor Day. Temperatures should climb into the lower to mid-70s with comfortable humidity, making Monday particularly favorable for outdoor holiday plans.

A weak cold front will approach from Quebec and cross the region Monday night into Tuesday, possibly bringing a brief shower before cooler and drier air returns. Tuesday and Wednesday should then be mainly dry and seasonably cool as another area of Canadian high pressure builds into northern Maine. Clearer skies and light winds may promote patchy Saint John River valley fog during the cooler nighttime periods.

The pattern becomes more unsettled again Wednesday night into Thursday as the next disturbance approaches from the west. Clouds and moisture will increase, followed by a growing chance of showers Thursday. An isolated thunderstorm may also be possible, although the timing and strength of the system remain somewhat uncertain.

Labor Day: A very pleasant holiday is expected across Fort Kent and the Saint John Valley as high pressure provides abundant sunshine, dry conditions, and comfortable humidity. Temperatures should rise into the lower to mid-70s, several degrees above early-September normals. Clouds may increase somewhat Monday night as a weak trough approaches, with a small chance of a late-night shower. Lows should settle into the upper 40s to around 50°F.

Tuesday: A weak frontal passage will usher cooler air back into northern Maine. A lingering early shower is possible depending on the timing of the boundary, but most of Tuesday should be dry with clouds giving way to increasing sunshine. Highs should reach the lower to mid-60s. Tuesday night looks partly cloudy and cool, with lows generally in the lower to mid-40s; patchy Saint John River valley fog may develop late where winds become light.

Wednesday: Cooler high pressure should provide another largely dry day. Expect a mixture of sunshine and clouds, with highs generally in the lower to mid-60s. Clouds should increase Wednesday night as the next disturbance approaches from the west. Showers may develop overnight, with lows in the upper 40s to around 50°F.

Thursday: The next system should bring a return to more unsettled weather. Current guidance favors mostly cloudy skies with periods of showers, although the timing and coverage remain uncertain this far out. Enough instability could develop for an isolated thunderstorm, depending on the system's track and timing. Highs should reach the mid- to upper 60s. Thursday night should remain mostly cloudy with a chance of showers and thunderstorms and lows in the mid- to upper 40s.

The latest Climate Prediction Center outlook favors slightly above-normal temperatures and precipitation across northern Maine. Broad ridging is expected across much of the eastern United States, although lingering troughing near Atlantic Canada may temper the warmer signal across northern New England. Early to mid-September climatology across the Saint John Valley generally features highs in the mid-60s and lows in the lower to middle 40s, with temperatures gradually declining through the month.

Outlooks updated 7-9 AM weekdays & 8-10 AM weekends and holidays. Long range outlooks indicate broader temperature and precipitation trends rather than precise day-to-day forecasts.

Updated every 3-6 hours from NWS Caribou

Weather Notice: This information is based on available computer models and data and may not reflect current conditions or later forecast updates. Always visit NWS Caribou at https://www.weather.gov/car/ for the latest official watches, warnings, and advisories for northern Maine.

Credits

• Sun/Moon data from US Naval Observatory with additional information from timeanddate.com.
• NOAA Warning Banner provided by WillyWeather.com.
• Until Dec. 2026, additional Archived Weather Data from Apex Wx is at the University of Utah's MesoWest
• Apex Wx Weather Data at Synoptic Data (successor to MesoWest)
  
• Apex Wx logo by Joanna Becker ©2016 (Visit Bushi and Brush Arts Dojo)

How accurate are forecasts? On average, for the first 72 hours the accuracy is 90 percent. For days 4-7 it is 70 percent. After seven days, it is 50 percent—just good for indicating trends. On social media and other similar sites, posts that show a forecast model run a week out are just for clicks and likes, and are not considered reliable. Extended forecasts are subject to change as weather patterns evolve so should be considered guidance rather than precise predictions. Check for updated forecasts and advisories as conditions develop.