Marine Weather and Tide Forecast for Augusta, ME

NEAR TERM /TODAY/

645AM Update...Just a few updates to temps, dewpoints, and sky but nothing major as the forecast appears to be in good shape. Even though radar looks to be showing precip in southern NH, no reports of any reaching the ground yet...but light rain is being reported upstream at KRUT in southern Vermont, so this should be the case in portions of southwest NH within the next hour or so.

Previous...

High clouds have really filled in over the last couple of hours ahead of an upper trough currently about to enter the Great Lakes region and associated surface low moving across the OH Valley. Ahead of these features, cloud bases will continue to lower today, but there's a lot of dry air to erode before any precip reaches the ground. So no precipitation is expected over the next couple of hours, but portions of western and southern NH may start seeing a bit of light rain or sprinkles around daybreak.

Per latest hi-res guidance, light rain will continue moving into southern NH this morning and could reach as far north as central NH and into southwestern ME, but there is uncertainty on how far north it will progress as it will be battling dry air.
But going into this afternoon, isentropic ascent increases, and the drier air to the north will start eroding, allowing the light rain to slowly start progressing farther north and east, probably reaching the Augusta and Midcoast regions by late afternoon or early afternoon.

Clouds and precip will hold most in the 40s today, but areas to the north and east where the precip holds off the longest could still reach the lower 50s.

SHORT TERM /TONIGHT THROUGH MONDAY/
The upper trough will continue digging across the Great Lakes tonight and eventually close off near the St. Lawrence Valley while the weak surface low moves east over southern New England.

With this system getting closer to the area, continued moistening and isentropic ascent the precip shield will make more of a push to the north and east this evening with steady rain expected for most of the region overnight. Cooling temperature profiles across the western ME mountains and northern NH suggest that some of this precipitation may fall as snow, especially in the higher elevations, but it's possible lower elevations see a brief period of snow as well. Any accumulations are expected to be light and confined in the higher elevations, except Mt.
Washington could pick up a couple inches.

The weak surface low will lift north and east across the Gulf of Maine Monday morning, and winds will gradually switch to the northwest and carry in drier air in the mid levels. The steadier rain is expected to taper off from southwest to northeast as a result, but forecast soundings do indicate low ceilings and patchy drizzle lingering through much of the morning and even into early afternoon toward the Midcoast and Augusta regions. For the afternoon south of the mountains, should start getting some breaks in the clouds as mixing improves. This will steepen lapse rates and create a small amount of instability, and with the area under the influence of the upper low, expecting some additional showers to develop.
High temps are forecast to reach the mid 40s to lower 50s.

For the mountains, skies will remain cloudy through the day Monday as upslope flow takes over. Scattered rain and/or snow showers will continue with temperatures profiles supporting more in the way of snow showers going up in elevation, although lower elevations could still see a few flakes. A light dusting is possible in the mountains, except an inch or two in the highest elevations.

Total rainfall accumulations from today through Monday are expected to be mostly between 0.50" to 1.00" across the region.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/
Pattern Overview: An active Fall pattern begins as a potent vertically stacked low pressure system continues to meander to our north through Tuesday. Afterwards, the 500 mb closed low remains overhead on Wednesday before pulling away Thursday morning. Another trough quickly dives through Thursday night before heights look to build on Friday and Saturday.

Impacts: * Potential for snow continues through the first half of the week in northern zones, mostly at elevation. No significant travel impacts expected.

Light upslope snow showers look to continue in the mountains through Tuesday with dry conditions elsewhere as a drier airmass moves in. Tuesday also looks like another blustery day with westerly winds gusting 20-25 mph.

Low pressure departs off to the east Wednesday slowly bringing upslope snow showers to an end. Surface high pressure then builds in which will begin to clear things out. High temperatures on Wednesday and Thursday will generally be in the 40s and 50s as it looks like we have mostly clear skies and well mixed forecast soundings. This will get low temperatures into the 30s each night as well, but still above freezing across much of the interior and coastal plain.

The drying and warming trend continues through Friday and Saturday as heights continue to build, pushing 850mb temps close to 10C based on the latest ensemble guidance. Trends will have to be watched as another potentially prolonged dry period may bring about fire weather concerns as foliage gets past peak and ends up on the ground. Also of note, the current forecast pushes Portland and Concord into the top ten for latest Fall freezes, with Concord more likely to see one this week.

AVIATION /08Z SUNDAY THROUGH THURSDAY/
Short Term...Low pressure approaches today with -RA moving into southern NH and southwest ME this morning and early afternoon.
However, ceilings and visibilities are expected to remain VFR as this is expected to be light. Ceilings will steadily to lower to MVFR this afternoon and then IFR by early evening at most sites, except a little later toward AUG and RKD. Visibilities will also lower as rain continues to overspread the region. IFR to LIFR conditions expected tonight as rain, low ceilings, and fog continue. Steadier rains should gradually wind down Monday morning from southwest to northeast, but could be followed by a period of drizzle with continued low ceilings. Gradual improvement is expected through Monday afternoon with scattered showers possible, but HIE and/or LEB are expected to hang on to MVFR ceilings with upslope flow.

Long Term...Most terminals should be VFR by Monday night with the only exception being HIE as snow showers will continue in the mountains. This will be the case through Wedensday with VFR becoming the prevailing condition at all terminals by Wednesday night. Westerly winds gusting 20-25 kts are possible Tuesday.

MARINE
Short Term...Winds become more east to northeast later today and increase as low pressure approaches and moves across the Gulf of Maine tonight and into Monday. As this occurs, gusts to 25 kt are possible for a brief duration tonight across the outer waters. Another period of SCA gusts could occur as the low lifts north and pulls a cold front across the waters Monday afternoon with brisk westerly winds taking over.

Long Term...Low pressure north of the waters Monday night through midweek will bringing westerly wind gusts generally 20-25 kts through Wednesday. Winds and seas relax toward late week as high pressure builds into the Northeast.

GYX WATCHES/WARNINGS/ADVISORIES
ME...None.
NH...None.
MARINE...None.