Portland, Maine – A milder air mass building into New England ahead of St. Patrick’s Day will push more of Maine’s upcoming systems toward rain, but nighttime cooling could still trigger bouts of wet snow between March 11 and March 17.
According to the National Weather Service Climate Prediction Center, Maine remains in a 40-50% probability zone for above-normal precipitation during the 8-14 day period. Unlike colder parts of the Upper Midwest, temperatures across Maine are projected to trend near to slightly above seasonal averages. That shift favors daytime rain in many communities, though marginal nighttime readings may still support rain-to-snow transitions.
In Portland and along the Interstate 95 corridor south toward Biddeford, daytime highs climbing into the 40s could keep most precipitation liquid. However, if steadier precipitation lingers after sunset and temperatures dip into the lower 30s, wet snow could briefly accumulate on grassy surfaces and untreated secondary roads. Farther north toward Augusta, Bangor and into Aroostook County, slightly cooler surface temperatures may allow more consistent snow, especially during pre-dawn hours.
Along the Downeast coastline, onshore winds will play a key role in keeping temperatures above freezing, limiting snow potential except during heavier bursts. Reduced visibility remains possible statewide during steadier rainfall.
Drivers across Maine should monitor overnight road conditions where temperatures hover near freezing. Even brief wet snow can create slick spots on bridges and elevated roadways. Additional updates are expected as the March 11-17 window approaches and system timing becomes clearer.
