Apex Wx

Overview: A strong coastal storm south of New England will remain the dominant regional weather feature through the weekend, while high pressure stays anchored across Quebec. The storm will bring rain, strong northeast winds, and coastal impacts to Downeast Maine, but the Saint John Valley should remain near its far northern fringe. Dry air feeding southward from Canada will continue to resist the northward advance of Atlantic moisture, keeping significant rainfall well south of northern Aroostook County.

Friday should remain unusually mild and mainly dry, although clouds will gradually increase as moisture circulates around the distant storm. Cloud cover becomes more persistent Saturday, resulting in somewhat cooler daytime temperatures while the Valley remains largely removed from the rain.

By Sunday, the pressure difference between the Quebec high and coastal low will strengthen, making northeast winds more noticeable across the County. The precise northern extent of the storm’s moisture remains the principal forecast uncertainty, and shower chances may begin edging northward Sunday night. At present, however, the SJV remains favored for a predominantly dry weekend.

Monday, September 28 – Thursday, October 1

Overview: The slow-moving coastal storm affecting Maine through the weekend will remain influential Monday as it gradually weakens and pulls away. Northern Aroostook County will remain near the northern edge of its moisture, allowing scattered showers to reach the Valley while the more persistent rainfall stays farther south. Rainfall locally should remain relatively light, with considerable cloud cover keeping Monday temperatures somewhat cooler.

The coastal system should steadily lose its influence Monday night into Tuesday, allowing drier air to spread across the County. A few showers may linger early Tuesday before conditions improve, followed by a brief period of weak high pressure Tuesday night into Wednesday. Increasing sunshine will support a noticeable midweek warm-up, with temperatures returning well into the 60s.

The next change begins Wednesday night into Thursday as another disturbance approaches from the west. Clouds will gradually increase across the SJV, although much of Thursday currently appears dry and relatively mild. By Thursday night, deeper moisture begins arriving, bringing mostly cloudy skies and a slight chance of rain showers as temperatures remain unusually mild around 50°F.

Monday: Clouds will remain fairly extensive as the weakening coastal system continues to influence northern Maine. Scattered showers are possible during the day, but significant rainfall is not expected in the Valley. Highs should reach the upper 50s to around 60°F. Shower chances continue Monday night before gradually diminishing, with lows in the lower to middle 40s.

Tuesday: A few showers may linger early before the departing system finally loses its influence. Increasingly dry conditions and some breaks of sunshine should develop during the day, with highs in the the upper 50s to lower 60s. Tuesday night remains mostly cloudy to partly cloudy and dry, with lows in the mid-40s.

Wednesday: A much brighter and milder day is expected as weak high pressure becomes established. Mostly sunny skies should allow temperatures to rebound into the mid- to upper 60s. Clouds increase Wednesday night ahead of the next disturbance, with lows rising only modestly downward into the upper 40s to around 50°F and a slight chance of showers developing late.

Thursday: Partly sunny and relatively mild conditions are favored for much of the day, with temperatures reaching the upper 60s to around 70°F. Clouds should become more prevalent as the next system approaches. Thursday night will be mostly cloudy and mild, with a slight chance of rain showers and lows around 50°F.

Weather Notice

Apex Wx forecasts are based on available observations, computer model guidance, and other meteorological data. Conditions and forecast guidance can change, and information displayed here may not reflect the latest official forecast or warning information. Always visit NWS Caribou for the latest official forecasts, watches, warnings, and advisories for northern Maine.

Apex Wx is a private weather information service unaffiliated with NOAA or the National Weather Service and operated by Joseph Becker. Dr. Becker earned a Certificate in Weather Forecasting from Penn State University and is a trained NWS SKYWARN Storm Spotter.

Credits

• Sun and Moon data from the U.S. Naval Observatory, with additional astronomical information from timeanddate.com.
• NOAA warning banner provided by WillyWeather.com.
• Through December 2026, additional archived Apex Wx weather data are available through the University of Utah's MesoWest.
• Current and archived Apex Wx weather data are available through Synoptic Data, the successor to MesoWest.
• Apex Wx logo by Joanna Becker © 2016. Visit Bushi and Brush Arts Dojo.

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