textproduct: Caribou

SYNOPSIS

A cold front crosses Maine tonight, followed by high pressure building in through Sunday. An area of low pressure tracks from northeastern New York Sunday evening to near southeastern Nova Scotia Monday morning. High pressure builds in behind this system through Monday night, then slides offshore on Tuesday. Another weak low tracks across the Gulf of Maine Tuesday night. A stronger low pressure system tracks from the Great Lakes Wednesday morning to the southern Canadian Maritimes by Thursday morning, followed by a cold front crossing the area on Thursday.

NEAR TERM /THROUGH SUNDAY NIGHT/

Two weak events will bring a modicum of snow to the forecast area through Sunday night. An Arctic front will cross tonight, bringing some snow showers mainly to Northern Maine. This front appears to be increasingly dry as it approaches the region, so not much snowfall is expected. What this front will do, is bring a cold air mass which will remain in place through Sunday night. This will drop temperatures to well below normal on Sunday and Sunday night, ensuring that any precip that falls with the weak low approaching Sunday night will fall as snow.

Sunday evening, a low pressure system will develop over the Gulf of Maine and move northeast along the coast. This will bring light snowfall through Sunday night, mostly to Downeast Maine. The heaviest period of snowfall will be late Sunday night, but all in all, less than 3 inches of accumulation is expected.

SHORT TERM /MONDAY THROUGH TUESDAY/

The axis of a northern stream trough crosses the area Monday morning, supporting some snow across mainly across southeastern portions of Downeast Maine. It should be dry Monday afternoon throughout with decreasing clouds with a colder and drier air mass moving in on NW flow aloft. Highs on Monday should be around 20 degrees below normal - mainly in the 10s, with wind chills generally in the negative single digits. Wind gusts of 25-35 mph probable on Monday.

The flow aloft backs from NW to WNW Monday night, with corresponding warm air advection aloft. Should see some increase in cloud cover as a result. Lows Monday night should be around 15-20 degrees below normal, with wind chills around -5 to -15.

Zonal flow Tuesday morning gives way to northern stream shortwave ridging building in during the afternoon. The subsidence should be sufficient to keep things dry, but there will be sufficient moisture advection ahead of the next system to bring in mid and high clouds, especially in the afternoon. Highs on Tuesday should be around 10-15 degrees below normal.

LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/

A northern stream shortwave crosses the area Tuesday night bringing some mainly light snow to the region, with the best chance of snow, including possibly moderate snowfall, being across Downeast Maine.

Another northern stream shortwave crosses the area from Wednesday into Wednesday night, exiting to the east late at night. This should bring a widespread snow to the North with rain across most of Downeast Maine, with a rain/snow mix in between. There is the potential for a plowable snowfall if current trends hold.

Another northern stream shortwave crosses the area on Thursday, bringing the chance of some snow showers across the North, rain showers across coastal Downeast, with a mix of rain and snow showers possible elsewhere.

The models then differ in timing/placing of systems Thursday night-Saturday, with solutions ranging from dry, to isolated to scattered showers, to a coastal low. For now went with slight chance to chance pops during this time frame. Until the models are able to sort out the main players in this time frame, the forecast could be quite volatile in this time frame. The one consistent signal is that it should continue to be seasonably cold late next week. That would tend to favor any precipitation being in the form of snow, except possibly a rain/snow mix near the coast.

Temperatures should be near to slightly below normal Tuesday night-Thursday, then below normal Thursday night-Saturday.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

NEAR TERM: TAFs starting out mainly VFR today, with cigs dropping to MVFR overnight in -SHSN. IFR conditions possible in snow showers, mainly earlier in the period with the heavier showers. Becoming VFR at all sites Sunday morning, lasting through Sunday evening. Sunday night, MVFR across the north with MVFR tempo IFR at BGR and BHB in -SN. Light SW winds becoming NNW 10 kts.

SHORT TERM: Monday...VFR, except for MVFR or lower possible at KBHB early. NW-W winds G20-30KT probable.

Monday night-Tuesday...VFR. W winds G15-25KT possible Monday night, SW-S winds G15-20KT possible Tuesday.

Tuesday night-Wednesday evening. MVFR or lower possible, with snow across the North, and snow Tuesday night, then rain and/or snow at southern terminals Wednesday-Wednesday evening. LLWS possible Tuesday night-Wednesday evening, with the highest chance at southern terminals.

Late Wednesday night-Thursday...becoming VFR late Wednesday night. W winds G15-25KT possible Thursday.

MARINE

NEAR TERM: A few gusts to 25 kts tonight, mainly on the outer waters. Light winds and seas on Sunday, then increasing N/NE winds Sunday night. Potentially increasing to gales late Sunday. Seas 2 to 4 feet.

SHORT TERM: Gale conditions possible on the coastal ocean waters Monday, will highlight this threat in the HWO. Otherwise SCA conditions likely on all waters from Monday into Monday night. There could be a period of sub-SCA conditions Tuesday morning, before SCA conditions probably return to all waters Tuesday afternoon. Gales are probable on the coastal ocean waters Tuesday night, with this threat also highlighted in the HWO, with SCA conditions likely on the intra- coastal waters. SCA conditions are then probable on the coastal ocean waters and possible on the intra- coastal waters Wednesday- Thursday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...None.