textproduct: Caribou

WHAT HAS CHANGED

650 am update... Regional radars showing a void in precip over Downeast zones which indicates drizzle and/or freezing drizzle already occurring. Have passed onto day shift that coastal zones may be able to be dropped out of the advisory this morning.

Upgrade to Winter Storm Warning over North Woods and Northeast Aroostook County.

Areas of blowing snow over central and north Monday morning into Monday afternoon.

KEY MESSAGES

1) Snowfall amounts across the north have increased leading to difficult travel today and tonight with freezing drizzle over Downeast leading to slippery conditions.

2) Areas of blowing snow downwind of open and agricultural areas Monday will lead to extremely hazardous travel with blowing and drifting snow.

3) Low pressure lifting up to our north on Wednesday will bring some light rain across southern areas and snow changing a mix then rain north.

4) A strong cold front will cross the area Thursday morning followed by abruptly falling temperatures and a chance for icy roads.

5) Bitter cold expected Thursday night into Friday.

DISCUSSION

KEY MESSAGE 1 Snowfall amounts across the north have increased leading to difficult travel today and tonight with freezing drizzle over Downeast leading to slippery conditions.

KEY MESSAGE 1 DESCRIPTION... Surface low in the initial stages of developing off of the eastern end of Long Island. Regional radar image showing fairly light echoes moving in from western Maine with light rain being reported at BHB and light snow at Bangor as of 06z. Not really sure what to make of these light echoes though 03z RRFS is showing this but quickly fills back in as coastal low starts to take over in the next hour or two. This puts a question on how winter weather advisories will be affected with possibly lower snowfall totals acrs central areas where 4 inches of snow is being forecast. Given lighter echoes and trend of bringing freezing drizzle further north than interior Downeast this morning, may need to adjust thru the morning hours to highlight less snow and more icing for areas in the Upper Penobscot Valley and portions of southern Aroostook.

Have adjusted end time of the advisories over Downeast and the Bangor Region as snizzle expected to move in after 13z this morning before exiting into NB this afternoon. Therefore only expecting hazardous travel with falling precip until mid-late afternoon. Though falling temps will result in black ice for southern areas overnight.

Further to the north, have increased snow totals slightly, into the 6-9 inch range, with isolated locations possibly hitting the 10 inch mark. WV imagery showing upper level diffluence over nrn New England and heading toward nrn portions of CWA. Thus, expecting a quick thump of snow at onset with around 5 inches over the North Woods through sunrise this morning. We've been advertising this storm as being two separate waves though still considered to be one storm. Expecting snow to lighten this afternoon before picking up again overnight, albeit lighter than previously though. Still expecting to see an additional 1-3 inches through Monday morning. Snow over the north of 6 to 9 inches likely to impact the morning commute, especially once the blowing and drifting kick in as noted in Key Message 2.

KEY MESSAGE 2 Areas of blowing snow downwind of open and agricultural areas Monday will lead to extremely hazardous travel with blowing and drifting snow.

KEY MESSAGE 2 DESCRIPTION... As the low deepens over the Maritimes pressure gradient strengthens with H9 winds around 30-35kts between 10-15z Monday. Peak time of wind gusts from the northwest of between 30 to 35 mph will be right around 12z Monday and the time of the morning commute. This will lead to blowing and drifting of the fresh snow pack across the north. This will effect mainly east-west roads downwind of the agricultural areas.

KEY MESSAGE 3 Low pressure lifting up to our north on Wednesday will bring some light rain across southern areas and snow changing over to a mix then rain across the north.

KEY MESSAGE 3 DESCRIPTION... Low pressure along a frontal boundary will track across Quebec north of the St. Lawrence Valley on Wednesday. The gradient between high pressure to our east and the low lifting up to our north will bring a southerly wind and warm advection across the area. The system will bring a chance of rain south and a chance of snow north with snow over the north possibly mixing with or changing to rain late Wednesday or Wednesday evening.

KEY MESSAGE 4 A strong cold front will cross the area Thursday morning followed by abruptly falling temperatures and a chance for icy roads.

KEY MESSAGE 4 DESCRIPTION... Low pressure continuing into Eastern Canada combined with high pressure building in from Central Canada will push a strong cold front into the area Thursday morning. Cold air along the southern edge of a core of Arctic air over Eastern Canada will filter into the area along the front on Thursday. Wet roads from rain and wet snow Wednesday night into early Thursday morning may become icy as temperatures fall Thursday morning. This has the potential to produce icy conditions for the morning commute on Thursday, mainly across the north.

KEY MESSAGE 5 Bitter cold expected Thursday night into Friday.

KEY MESSAGE 5 DESCRIPTION... Arctic air infusing into the region behind Thursdays cold front will bring a return of very cold weather with lows Thursday night from the single digits below zero in the northwest to the mid teens near the coast and highs Friday from the mid teens over the north to the mid 20s along the coast. Wind chills on Friday will range from near zero north to the low teens by the coast.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

MVFR/IFR conditions for Downeast terminals today with a wintry mix expected. FZDZ will be the most impactful to runways today before switching back over to light snow later this afternoon/evening and ending after 03z tonight.

Northern Aroostook terminals look to be pure IFR/LIFR snow today, with heaviest snow falling through 18z this afternoon before lightening up to IFR. Snow may become heavy again after 00z this evening but quite a bit of uncertainty at this time.

The wild card remains KHUL. IFR/LIFR snow expected this morning before possibility of FZDZ moves in between 15-00z today. Still have very low confidence in TAF for HUL.

Winds out of the E/NE 5-15kts today into this evening. Winds will back around to the NW and increase after 06z Monday. NW winds 10- 20kts gusting to 30-35kts will lead to MVFR or IFR in blowing and drifting snow at northern terminals into early Monday afternoon. Late afternoon winds will lighten to 10-20kts from the W.

Monday night...MVFR to VFR south. MVFR north. Light SW winds.

Tuesday...VFR south. MVFR becoming VFR north. Light SW winds.

Tuesday night...VFR dropping to MVFR then IFR late. S winds.

Wednesday...IFR. S winds.

Wednesday night...IFR. S winds, becoming N late.

Thursday...IFR becoming VFR north and MVFR south. N winds.

MARINE

SCA in effect today, for easterly wind gusts initially with seas between 2 to 4 feet. Winds diminish as low tracks over the waters with seas building in serly swell in the afternoon. Seas build to between 5-10 feet Monday morning as winds become WNW and begin gusting aoa gale force toward midnight tonight. Winds diminish below gales Monday afternoon with small craft conditions expected thru the end of the day.

A gale may be needed late Tuesday night into Wednesday for winds gusting up to 35 kt over the offshore waters. Winds will diminish to SCA late Wednesday and below SCA Wednesday night. A SCA and possibly a gale may be needed Thursday night into Friday for gusty N winds.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Winter Storm Warning until 4 AM EST Monday for MEZ001>004. Winter Weather Advisory until midnight EST tonight for MEZ005- 006-010-011-031-032. Winter Weather Advisory until 4 PM EST this afternoon for MEZ015>017-029-030. MARINE...Small Craft Advisory until 10 PM EST this evening for ANZ050>052. Gale Warning from 10 PM this evening to 4 PM EST Monday for ANZ050>052.