Marine Weather and Tide Forecast for Southwest Harbor, ME

NEAR TERM /THROUGH FRIDAY/
Fast moving low pressure will cross the region tonight with scattered rain showers. Otherwise, expect mostly cloudy skies north with partly/mostly cloudy skies Downeast tonight. High pressure crosses the region Friday, exiting across the Maritimes late. At the same time, low pressure tracking across the Great Lakes will draw a warm front towards the region later Friday. Expect partly sunny/mostly cloudy skies across the region Friday. Could also have a slight chance of rain approaching western portions of the forecast area late Friday afternoon. Low temperatures tonight will range from around 40 north to the lower 40s Downeast. High temperatures Friday will range from the lower to mid 50s north, to the lower to mid 60s interior Downeast with mid 50s to around 60 along the Downeast coast.

SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/
Low pressure system moves in from Ontario, bringing rain for the weekend. Warm front associated with the low brings some warm air into the region on Friday night into Saturday, alongside plenty of moisture. Forecasting skies to stay mostly cloudy overnight, with low temperatures in the low-40s throughout northern Maine.
925mb Jet passes as the system moves into Maine, causing some gusty winds on Saturday, predominantly along the coast.

Low system moves into Quebec on Saturday, with moderate rainfall occurring during the day. Warm air continues to funnel in, but with southwest flow and ample cloud cover, high temperatures are looking to stay in the high-40s/low-50s.
Highest precipitation amounts forecast to fall during the day and evening on Saturday, specifically along the Washington county coastline Saturday afternoon. Overnight, low moves into Maine, as cold air gets advected in behind the associated cold front. GFS is indicating an aggressive dry slot at 700mb Saturday night, but low levels stay moist, but rain begins to taper down in intensity. Can’t rule out a few snowflakes to mix in at higher elevations. Lows forecast to be in the mid-30s.
High begins to build in over the Great Lakes on Sunday, as low pressure system moves out to the Atlantic. Rain begins to taper off from west to east. Storm total precipitation around 1-1.5 inches throughout northern and Downeast Maine. Highs forecast to be in the low 50s.

LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
Sunday night, low pressure over Maine moves out to Nova Scotia, as high pressure pushes east. Behind the low, tight pressure gradient follows which could produce some gusty winds. Next system approaches on Tuesday. Warm front associated with it brings in plenty of warm air, helping temperatures to rise into the high-60s. Rain showers forecast throughout Maine. As front passes that evening, could be some favorable temperature gradients and lift for a few scattered thunderstorms in the north. System moved away by Thursday, as a skinny ridge develops by Friday. Forecasting highs in the 50s/60s, and low temperatures in the 30s/40s.

AVIATION /20Z THURSDAY THROUGH TUESDAY/
NEAR TERM: Generally VFR/MVFR tonight, though local IFR also possible overnight. Scattered showers tonight. Occasional MVFR ceilings possible early Friday. Otherwise, VFR Friday. Variable winds 5 to 10 knots tonight. Northwest/north winds 5 to 10 knots, becoming variable Friday.

SHORT TERM: Friday Night.. MVFR conditions as rain showers move in from the west. NE winds that turn SE at 5-10kts, gusting to 15-20kts possible.

Saturday-Saturday Night.. MVFR/IFR conditions due to rain and low ceilings. LLWS possible throughout the day. Winds from the S-SE at 5-10kts, that then shift NW overnight. Gusts 20-25kts possible.

Sunday-Sunday Night.. MVFR conditions due to linger rain showers. Winds NW at 10-15kts with gusts up to 25kts possible.
LLWS possible Sunday night.

Monday-Monday Night...VFR conditions. Winds from the NW at 5-20kts, then shifting to the SW overnight. Gusts 15-20kts possible.

Tuesday.. MVFR conditions as rain showers move in. Potential for scattered thunderstorms at far northern terminals. Winds from the S at 5-10kts. Gusts 15-20kts possible in the evening.

MARINE
NEAR TERM: Winds/seas below small craft advisory levels tonight through Friday. Scattered showers tonight.

SHORT TERM: Small Craft Advisory conditions begin during the day Saturday, jumping up to possible Gale conditions by evening.
Conditions start to fall below Small Craft criteria during the day on Sunday. Seas get as high as 8 ft on the outer waters Saturday night, and 6 ft at the intra-coastals. Potential for a low end Small Craft Advisory on Wednesday next week. Winds from the SE Friday night, and shift to the W by early Sunday morning.
Rain showers that may reduce visibility throughout the weekend, ending on Monday.

CAR WATCHES/WARNINGS/ADVISORIES
ME...None.
MARINE...None.