textproduct: Caribou

WHAT HAS CHANGED

- 6:29AM UPDATE...12z TAF UPDATE. See below. Increased cloud coverage for this afternoon into the overnight hours. Hi-res guidance indicating a low to mid level deck developing this afternoon with the NW winds off the still open St. Lawrence seaway. It is also possible for some flurries to develop with these clouds and have added flurry mentions for this afternoon then again tonight. Better chance of scattered flurries tonight when moisture increases in the boundary layer trapped under the inversion.

KEY MESSAGES

- Cold Arctic air and gusty winds will result in frigid wind chills tonight into Sunday morning.

-Increasing chances for some snow Tuesday night with possible impacts to the Wednesday morning commute.

DISCUSSION

KEY MESSAGE 1...Cold Arctic air and gusty winds will result in frigid wind chills tonight into Sunday morning.

KEY MESSAGE 1 DESCRIPTION... Snow showers this morning associated with deepening 500mb low to our south is bringing colder air into Maine. Cold air advection has been a little slow to start but expecting temperatures to continue to fall through the morning hours. Winds are increasing across the area as surface low pressure deepens well to our south-southeast. The airmass that originated from the North Pole back on Jan 28-31st will hang somewhat back to the west into tomorrow but a piece of the coldest part is over the western half of the CWA today. Temperatures bottom out in the single digits below zero this morning from the Moosehead Region northward to the St. John Valley with temps ranging 0-5F across the rest of the north. Bangor Region to Downeast bottoms out 5-10F.

Winds will increase and gust 20-30mph this morning as the pressure gradient tightens between the deepening low SE of the area and 1037mb surface high building in from Ontario. Winds at the top of the mix layer this morning (approx 2kft) is in the 25-35kt range so combining the temps and winds wind chills will be below zero for most areas. 5-10 degrees below zero Downeast, 10-15 below zero for Bangor Region to Houlton to Caribou. Moosehead Region to North Woods and St. John Valley looking at wind chills of 20 to 25 below zero. Cold Weather Advisory remains in effect for N. Somerset County where wind chills will reach criteria of -25F. Partly to mostly sunny today, did raise temps a couple degrees with slightly warmer airmass in place on the east side of the shortwave. Highs in the teens north, 9-12F for Moosehead Region and 20-25F for Bangor Region to Downeast Coast. Winds will remain gusty and trended the winds closer to the NBM75th-NBM90th percentile.

Tonight once again will need to monitor the trends in temps and winds for the Moosehead Region and N. Somerset about the possibility of Cold Weather Advisory headlines. Air temperatures will drop back -10F to -5F for the North Woods and Moosehead Region with -5F to +5F in most other locations in the CWA except around +10F at the shoreline. Watching the headlines needs because winds will remain breezy 10-15mph gusting 20-30mph at times. Latest thinking is wind chills dip to -27F to -23F range but those aren't fully widespread around Moosehead. Elsewhere winds chills of 10 to 20 below zero.

KEY MESSAGE 2...Increasing chances for some snow Tuesday night with possible impacts to the Wednesday morning commute.

KEY MESSAGE 2 DESCRIPTION... Low pressure approaches from Ontario province Tuesday and then tracks southeast off the coast of Maine Wednesday morning. Warm advection pattern in advance of the system will result in snow overspreading the region Tuesday night. The snow is expected reach on a line from Greenville to Bangor by around midnight and then the route one corridor from Houlton to Caribou between 3 am and 6 am Wednesday morning. There was enough model consensus to increase pops to likley across much of the forecast area later Tuesday night. As the low exits to the east of the coast to the south of Nova Scotia during Wednesday, a trof will extend back to the west. This will serve as the focus for continued snow during the day on Wednesday. The snow should gradually diminish later Wednesday and Wednesday night, although there may be the continued threat of scattered snow showers.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

12Z UPDATE... Today and Tonight...VFR this morning except MVFR at FVE. Expecting a period of VFR at the northern terms this morning becoming low end VFR to MVFR this afternoon. Cannot rule out brief flurries so added VCSH to these northern terms. Low end VFR or MVFR expected through tonight into the early AM hours of Monday. Southern terms expect VFR today into tonight. Area wide winds NW 10-15kt gusting 20-30kt. LLWS likely this evening into early Monday AM.

Monday...VFR. NW winds 5-15kt gusting up to 25kt.

Monday night and Tuesday...VFR.

Tuesday night VFR early, then MVFR or lower in developing snow.

Wednesday...MVFR or lower in snow.

Wednesday night amd Thursday...VFR/MVFR.

MARINE

Gale Warning remains in effect through midnight tonight for the Coastal Waters. N winds 20-30kt and gusts up to 40kt. Seas 3-6ft. A Small Craft Advisory remains in effect through midnight tonight for the Intra-Coastal Waters. N winds 15-20kt gusting up to 30kt and seas 2-4ft. A Freezing Spray Advisory remains in effect through 10AM EST Monday for all of the waters out to 25nm. Moderate accumulation of freezing spray likely. Freezing spray may render mechanical and electronic components inoperative. Ice accretion on decks and superstructures may result in some loss of stability. Sea surface water temperatures from the Downeast Coast out 25nm range 36-41F including Penobscot and Passamaquoddy Bays. Expecting winds to remain at SCA levels from early Monday morning through Tuesday AM and light freezing spray to continue.

SCA conditions are possible Monday night otherwise winds/seas below SCA levels through mid week.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Cold Weather Advisory until 10 AM EST this morning for MEZ003. MARINE...Gale Warning until midnight EST tonight for ANZ050-051. Freezing Spray Advisory until 10 AM EST Monday for ANZ050>052. Small Craft Advisory until midnight EST tonight for ANZ052.