textproduct: Caribou

SYNOPSIS

An Arctic cold front crosses the region on Thursday. High pressure builds across the region Friday into Saturday. A cold front crosses the region Sunday. High pressure builds toward the region Monday.

NEAR TERM /THROUGH THURSDAY NIGHT/

Update...

See updated aviation section.

Key Messages -Snow Squalls Likely Thursday, Brief Dangerous Travel Possible -Arctic Air Mass Arrives Thursday Night

Discussion... Tonight will be mainly benign across the CWA with 500mb weak ridging passing overhead. Mostly cloudy skies and temperatures falling back into the mid to upper teens north and upper teens to low 20s south. Winds light and variable slowly shifting S at 5-10mph overnight.

Thursday will feature a solid potent arctic cold front passing through the area. Hi-Res models along with the global models have come into really solid agreement on timing and the dynamics at play for Thursday. General timing is 7AM-10AM across the North Woods, Moosehead Region and Allagash Region. 8AM-Noon for Route 11 to Route 1 corridors in Aroostook County. 11AM-2PM for the I-95 Corridor from Houlton to Bangor to Newport. Then Noon-3PM for the Downeast coast. Looking at the dynamics at play we have very good agreement on non-zero CAPE, very steep low level lapse rates, a well mixed boundary layer 3-4.5kft deep. Winds at 3-4.5kft will be 30-40kt and much will mix down with FROPA. Given the best diurnal part of the day a sharp boundary and dynamics/thermodynamics supporting squalls will continue to message it. We do expect some heavy snow showers to potentially reach the need for SQWs tomorrow. Have placed the concerns in the HWO and will message via social media. Any snow shower to squall has the potential to reduce visibility to 1/4mi or less and produce a quick 1-2 inches of accumulations. As the front crosses the region expect rapidly falling temperatures with 6-12 degree temperature falls at FROPA.

Thursday night the arctic front will pass well SE of the state and strong cold air advection takes shape on W-NW winds. Using the NOAA Hysplit backward trajectory this airmass originated from Siberia Russia back on November 26th traveling over the North Pole to Canada and then soon here in Maine. Thursday night will be the coldest night so far this season. Air temperatures will fall back to -7F to -1F across much of the northern 2/3rd of the CWA. The Bangor Region to Calais will see -3F to +2F air temperatures with 0F to +5F along the Downeast coast and +5F to +10F for the islands. Expect widespread W-NW wind gusts 20-35mph with isolated stronger gusts especially in places like Greenville and the open agricultural areas of Aroostook and Northern Penobscot counties. Strong gusts combined with frigid temperatures will result in wind chills dropping to between -25F to -15F across much of the CWA. The Moosehead Region northward into the North Woods and NE Aroostook County may flirt with Cold Weather Advisory level wind chills but will hold off right now on potential headlines.

Blowing snow is possible from any recent snowfall as winds increase behind the cold front across any open areas that see wind gusts >25mph. Patchy blowing snow may cause localized whiteouts and dangerous driving conditions in the open areas of Aroostook and N. Penobscot counties. This could impact such roadways but not limited too; Routes 1, 1A, 2, 10, 11, 89, 161, 163, 167 and 212.

SHORT TERM /FRIDAY THROUGH SATURDAY/

High pressure will build across the region Friday through early Saturday. Expect mostly sunny skies early Friday, then partly sunny. Partly cloudy/mostly clear Friday night. Partly sunny early Saturday, then increasing clouds. Partly/mostly cloudy Saturday night with isolated snow showers. Much below normal level temperatures Friday, then below normal level temperatures Saturday.

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/

A strong cold front will cross the region Sunday with isolated/scattered snow showers. High pressure should build across the region Monday into early Tuesday with mostly clear/partly cloudy skies. Low pressure could then begin to approach later Tuesday with increasing clouds and chance of snow or snow showers. Low pressure could then bring a chance of snow or snow showers Wednesday. Slightly below normal level temperatures Sunday, then below normal level temperatures Monday through Wednesday.

AVIATION /00Z THURSDAY THROUGH MONDAY/

NEAR TERM:

KFVE/KCAR/KPQI/KHUL...VFR tonight all terminals through 12z Thursday, then MVFR in sct -SHSN, with locally brief LIFR in heavier snow showers 13z to 16z. VFR later Thursday through Thursday night. Light SW wind tonight, increasing to 10 to 15 kt late tonight, then becoming gusty W 15 to 25 kt Thursday afternoon and Thursday night.

KBGR/KBHB...VFR tonight. Mainly VFR Thursday and Thursday night but possible brief MVFR conditions later Thursday morning into Thursday afternoon in sct -SHSN. Light SW wind tonight, increasing to 10 to 15 kt late tonight, then becoming gusty W 15 to 25 kt Thursday afternoon and Thursday night.

SHORT TERM:

Friday through Friday night...Occasional MVFR ceilings possible north. Otherwise, VFR. West/northwest winds 10 to 15 knots with gusts up to around 20 knots, becoming west/southwest 5 to 10 knots Friday. Variable winds 5 to 10 knots Friday night.

Saturday...VFR early, then VFR/MVFR. Variable winds 5 to 10 knots, becoming south/southeast.

Saturday night...VFR/MVFR. Variable winds 5 to 10 knots.

Sunday...Variable conditions with snow showers. Otherwise, VFR/MVFR. Southwest winds 5 to 10 knots, becoming west/northwest 10 to 15 knots with gusts 20 to 25 knots.

Sunday night...VFR/MVFR. A chance of snow showers north, slight chance of snow showers Downeast. West/northwest winds 10 to 15 knots with gusts 20 to 25 knots.

Monday...VFR/MVFR north, VFR Downeast. West/northwest winds 10 to 15 knots with gusts 20 to 25 knots.

MARINE

NEAR TERM: A Gale Warning is in effect for the Intra-Coastal and Coastal Waters from 3PM Thursday till 7AM Friday. Tonight expecting seas to be 4-7ft across the waters but winds below SCA levels. SW winds tomorrow will increase to SCA levels by mid morning and gusting 30-35kt in the late afternoon. Winds will shift NW around or just before sunset and rapidly increase to NW gales. Tomorrow night on the Intra-Coastal Waters NW winds 20 to 30 kt with gusts up to 45 kt and seas 3 to 5 ft expected. On the Coastal Waters NW winds 25 to 35 kt with gusts up to 45 kt and seas 7 to 10 ft expected. Air temperatures will be rapidly falling tomorrow night into the single digits and teens. Although sea surface water temperatures are in the 45-48F range it is possible some areas with colder SSTs may see light freezing spray. Confidence is too low to put in the forecast at this time.

SHORT TERM: Small craft advisory conditions Friday into Friday night. Conditions below small craft advisory levels Saturday into Saturday night. Isolated snow showers possible Saturday into Saturday night.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...Gale Warning from 3 PM Thursday to 7 AM EST Friday for ANZ050>052.