Marine Weather and Tide Forecast for Brunswick Station, ME

NEAR TERM /UNTIL 6 AM SATURDAY MORNING/
1130 PM Update... The first batch of light rain is now located over the north and towards the Penobscot Valley with the next round of showers moving into southern NH. This activity will continue to lift northward overnight with perhaps some patchy fog developing late.

Previously...
700 PM Update... An area of light rain persists at this hour from southern Coos county in NH and extending southeastward towards Lewiston/Auburn and central Cumberland county. This rain is slowly advancing east-northeastward and is associated with a stationary front. Have increased PoPs across these locations as measurable rainfall of a few hundreds of an inch are likely but also lowered PoPs in most other locations. Otherwise, just blended in the latest surface observations at this time.

Previously...
Showers focused along a stationary front have been slowly moving across central NH this afternoon. So far these have been fairly light, and will tend to pull north ahead of the larger batch of rain arriving after midnight into early Saturday. Temperatures remain mild tonight, retreating to the 40s to around 50.

Low pressure will continue to deepen over the Great Lakes this evening and into early Saturday morning as upper trough amplifies into southern Ontario. Rapidly strengthening LLJ off the New England coast increases IVT and PWATs. Steadier rain looks to make its way into SW NH around daybreak and then ME around 8am.

SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/
Much of Saturday looks to be a washout, but rain rates and amounts keep flooding chances very low. The soaking rain will be beneficial for an otherwise dry April. As of Friday afternoon, Portland currently runs 0.7" below normal for rainfall this month, with Gray (0.93") and Augusta (0.89") also standing to benefit.

All in all, the system is fairly progressive, likely driven by the upper trough not developing a negative tilt until the Gulf of Maine. Precip efficiency may be held back due to a thinner warm cloud layer, but moderate to heavy rain is forecast to be falling through the morning. PWATs into the late morning may near GYX's daily max 12z RAOB value of 1.35". Coastal enhancement has been shown in today's CAMs, with increased values around Casco Bay up the Midcoast. Elevated instability could also aid in some rumbles of thunder over the coastal waters and along the coast Saturday.

The main period of rain pushes north through Saturday afternoon, with showers wrapping up the daytime. These become more isolated into the evening as dry air wraps around the low. Temps remain nearly steady until after midnight when NW winds arrive to bring cooler temps. Additional shower development is likely across central ME as some instability develops below the low.

LONG TERM /SUNDAY THROUGH FRIDAY/
04Z Long Term Update... Little change from the previous forecast in the latest NBM guidance. Other than a few showers possible Tuesday night, it looks relatively dry through the middle of next week before rain chances increase late week.

Previously...
Low pressure will be deepening over Downeast Maine Sunday before exiting into the Atlantic Sunday night. High pressure builds in Monday and Tuesday for dry weather and an upward trend in temperatures. A frontal system will cross Tuesday night and Wednesday with high pressure returning Thursday.

Sunday will be cool and cloudy with a surface low over Downeast Maine and an upper low crossing overhead. The 12Z model suite is in good agreement that precipitation will continue over the northern half of the CWA with colder air aloft allowing rain to change to snow in the mountains. Some dry air will wrap into the system Sunday morning leading to lower chances for rain showers south of the mountains. Highs will range from the mid 40s north to mid 50s south. As the low deepens to our east, north to northwest winds will increase Sunday afternoon with gusts 25-30 mph. Chances for precipitation diminish Sunday night with breezy NW winds continuing into Monday.

Monday will be dry will mostly sunny skies as high pressure builds in from the west. A NW gradient will persist into the afternoon with winds gusting 20-25 mph until high pressure moves closer to overhead Monday evening. Highs will range from the low 60s north to low 70s south. Heights build over New England Tuesday with high pressure shifting to the south. This will allow for warmer air to advect into the region bringing highs well into the 70s across NH and interior western Maine. Southerly winds will advect cooler marine air into the coast where highs will mainly be in the 60s.

Clouds increase late Tuesday into Tuesday night as a cold front starts to shift southeast out of Canada. This front will slowly cross overnight and Wednesday bringing mainly chances for showers.
Chances for showers will diminish through the day Wednesday as the front pushes offshore. High pressure and cooler air arrive for Thursday with the next system poised to approach Friday.

AVIATION /04Z SATURDAY THROUGH WEDNESDAY/
Short Term...VFR this afternoon and evening. Coastal terminals may see ceilings fall quicker this evening. A bank of low stratus or fog may move onshore mid to late evening. This will bring the possibility of quick onset IFR to LIFR ceilings.
Visibility restrictions are more uncertain, but may fall to IFR/LIFR after midnight in fog.

Elsewhere, ceilings will tend to lower to MVFR/IFR after midnight. SHRA becomes more widespread across all terminals after midnight, with RA more continuous through Saturday morning and early afternoon.

Strengthening winds off the surface will create LLWS Saturday morning with increasing rainfall rates.

IFR continues Saturday, with improvement towards VFR Saturday night for most southern NH and far southern ME terminals.

Long Term...Low pressure over Downeast Maine Sunday will maintain steady NW winds gusting to around 20 kts. Low cigs and showers will bring the threat of at least MVFR, especially at KAUG, KRKD, and KHIE. Mainly VFR Monday and Tuesday before a front crosses Tuesday night into Wednesday that will bring the chance for brief restrictions in showers.

MARINE
Short Term...A stationary front remains over the waters this afternoon as low pressure strengthens over the Great Lakes tonight. This low will dive into New England Saturday. SCA winds and building waves are forecast, with heavy rain and the chance of a rumble of thunder. Fog will also likely reduce visibility. The stacked low moves over the coastal waters Saturday night, bringing lighter wind gusts but wave heights slow to slacken.

Long Term...NW winds and elevated seas will likely continue SCA conditions Sunday into Monday morning. High pressure crosses the waters Monday and Tuesday with winds and seas below SCA thresholds. South to southwest winds increase late Tuesday ahead of a cold front with SCA conditions possible by Tuesday night.

GYX WATCHES/WARNINGS/ADVISORIES
ME...None.
NH...None.
MARINE...Small Craft Advisory from 6 AM Saturday to 8 PM EDT Sunday for ANZ150-152-154.
Small Craft Advisory from 10 AM Saturday to 2 PM EDT Sunday for ANZ151-153.