textproduct: Caribou

WHAT HAS CHANGED

-A Gale Warning has been issued for the offshore water beginning this afternoon and will continue through Friday night. A gale warning has also been issued for the intracoastal waters Friday night.

-Continued uncertainty in system approaching Gulf of Maine Sunday night into Monday.

KEY MESSAGES

1) Light snow early this morning may create some slippery travel for the morning commute, especially Downeast.

2) Snow squalls are possible today and likely on Friday, especially across central and northern parts of our region.

3) Frigid arctic air brings extremely dangerous wind chills this weekend

4) Chance of winter storm Sunday night into Monday

DISCUSSION

KEY MESSAGE 1...Light snow early this morning may create some slippery travel for the morning commute, especially Downeast.

KEY MESSAGE 1 DESCRIPTION... A weak occlusion will cross the area early this morning. As it moves through, a weak triple point low will form along our coast, and then track northeast into New Brunswick later this morning. The occlusion, in combination with the weak low, will support an area of light snow, mostly over east central and southeastern parts of our region early this morning. This may result in some slippery and messy travel during the morning commute. This initial area of snow will lift northeast and out of the region by mid morning as the occlusion moves through.

KEY MESSAGE 2...Snow squalls are possible today and likely on Friday, especially across central and northern parts of our region.

KEY MESSAGE 2 DESCRIPTION... Colder air will begin moving in aloft today as residual relatively milder air remains near the surface from the occlusion crossing the area. This will result in some steep lapse rates up to around 12K ft and CAPES just over 30 J/KG across parts of the area. The instability will likely spawn some snow showers over the north and an isolated snow squall will be possible. Any snow showers or squalls can cause an abrupt brief drop in visibility and coat the roads as it moves through.

An Arctic front pushing into the area on Friday will bring another chance of snow squalls. A weak weather disturbance will hold "relatively" milder air near the surface while much colder air begins to surge in aloft. This will again produce some instability with steep lapse rates up to around 10K ft and CAPES up to 60 J/KG. Any snow squalls on Friday will have a greater risk of having an impact because 1) Strong gusty winds may accompany the passage of the Arctic front causing blowing snow and a brief rapid drop in visibility with isolated white-out conditions and 2) temperatures quickly dropping behind the Arctic front from the teens into the single digits north and from the 20s into the teens Downeast will result in damp roads freezing and becoming very slippery. The best chance for any squalls will be during the midday and afternoon as the front pushes through.

KEY MESSAGE 3...Frigid arctic air brings extremely dangerous wind chills this weekend.

KEY MESSAGE 3 DESCRIPTION... Occluding low pressure system swings through Maine on Friday, as high pressure builds in from the west, well behind the front. In its wake, is an arctic air mass that will settle over the region this weekend, bringing bitter wind chills throughout northern and eastern Maine. Temperatures begin to drop on Friday, with overnight lows around 15 in the west, -10 in the north, and just below 0 Downeast. Gusty winds forecast with strong pressure gradient that develops over the region in between the two aforementioned pressure systems, resulting in wind chills around -30 to -40 in the north and west, around -30 in the Central Highlands, and around -25 to -20 in the Bangor and Downeast regions. High temperatures on Saturday will be just below 0 in the north, and the single digits Central Highlands and Downeast. Similar wind chill values could occur on Saturday as well, -30 to -40 in the north and west, -30 to -25 in the Central Highlands, and around -25 to -20 in the Bangor and Downeast regions. There is a chance for clearing to occur overnight, and alongside lighter winds, temperatures could plummet quickly. Highs on Sunday will be around 0 in the north, single digits in Central Highlands, and around 10 around Bangor region to Downeast. Wind chills will improve Sunday night, but not by much. Northern Maine expecting -25 to -15 chills, central Maine around -15 to -10, and Downeast around -10. A warming trend is expected Monday onwards. Exposure to these frigid temperatures can quickly result in frostbite and hypothermia.

KEY MESSAGE 4...Chance of winter storm Sunday night into Monday.

KEY MESSAGE 4 DESCRIPTION... Models have been hinting at the potential for a system to move through Sunday night into Monday, depending on how close this low pressure system gets to the Maine coastline. Currently, the ECMWF has a much stronger low pressure system, which shifts the system closer into the Gulf of Maine. This results in a higher chance for precipitation extending in central and northern Maine. The GFS remains conservative however, as it shows a solution where the high pressure system over the region has the low pressure go out out into the Atlantic down in southern New England. There is a chance for accumulating snowfall to fall, primarily in the Bangor region and Downeast. The most uncertainty is how far north this low could move north, and as a result, how far inland snow will get.

AVIATION /06Z THURSDAY THROUGH MONDAY/

Today...IFR early this morning improving to MVFR late morning then VFR this afternoon. Possibly briefly dropping back to MVFR or IFR in any snow showers central and north this afternoon. Some WSW wind shear early this morning, mainly south. Winds SW around 10 kt.

Tonight...VFR except possibly occasionally MVFR over the far north. WSW winds 5 to 10 kt.

Friday...Mainly VFR except possibly briefly lowering to MVFR or IFR in snow showers/squalls central and north midday into the afternoon. Winds W 10 to 15 kts with higher gusts.

Friday night through Saturday...VFR/MVFR north. VFR Downeast. W/NW winds 10 to 15 kts, with gusts up to 25 to 30 kts.

Saturday night through Sunday...VFR at all terminals. W/NW winds at 5 to 10 kts. Gusts 15 to 20 kts late Saturday night, diminishing during the day Sunday.

Sunday night through Monday...Becoming MVFR and possibly IFR by morning at southern terminals with snow. VFR/MVFR northern terminals, with a slight chance for snow showers by afternoon. Light N/NW winds Sunday night, shifting to the N by Monday. 5 to 10 kts.

MARINE

A strong SCA today increasing to gale over the outer waters this afternoon. A gale will continue across the outer waters tonight and Friday with an SCA across the intracoastal waters. Winds SW today and W tonight and Friday. Seas up to 9 ft today then 8 ft tonight and Friday.

Gale conditions persist into Saturday over the outer-waters. Outer-water seas reach up to 7-9 ft Friday night, gradually relaxing during the day Saturday. Gale Warning out for the intra-coastals from Friday night into early Saturday morning. Intra-coastal seas around 3-5 ft, gradually relaxing during the day Saturday. Light freezing spray Friday, becoming moderate freezing spray on Friday night, and then high freezing spray on Saturday. Relaxes back down to moderate freezing spray on Saturday, and light on Sunday. Winds from the northwest Friday night, shifting to the north by Sunday. Chance for snow showers on Friday. Chance for snow Sunday night into Monday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Extreme Cold Watch from late Friday night through Saturday morning for MEZ001>006-010. MARINE...Small Craft Advisory until 1 PM EST this afternoon for ANZ050- 051. Gale Warning from 1 PM this afternoon to 7 AM EST Saturday for ANZ050-051. Small Craft Advisory until 7 PM EST Friday for ANZ052. Gale Warning from 7 PM Friday to 7 AM EST Saturday for ANZ052.