textproduct: Caribou

WHAT HAS CHANGED

The expected track of the storm today has shifted further south and thus freezing rain is likely to remain primarily confined to central and coastal Washington and Hancock counties. Thus, have cancelled the winter weather advisory for northern Washington and central Penobscot counties.

Added patchy freezing drizzle just ahead of steady precipitation on Friday morning with freezing drizzle behind cold front.

KEY MESSAGES

1) Light snow across the north, with a mix of snow, rain, and freezing rain across Downeast Maine through this evening

2) Patchy freezing drizzle ahead of precipitation Friday morning and freezing drizzle behind cold front late Friday night

3) Potential Winter Storm Saturday Night and Sunday

DISCUSSION

KEY MESSAGE 1...

Light snow across the north, with a mix of snow, rain, and freezing rain across Downeast Maine through this evening.

KEY MESSAGE 1 DESCRIPTION...

Low pressure is expected to track east across upstate New York, then undergo secondary development in the the Gulf of Maine this morning before eventually exiting to the east, passing south of Nova Scotia while intensifying, later today.

Light snow is expected across northern and central Maine from this system with light accumulations of 1 to 3 inches. Expect the highest totals over southern and central Piscataquis county, especially in the higher terrain.

The Downeast region, particularly central and coastal Hancock and Washington counties, is where the greatest threat for freezing rain exists. Ice accumulations in these areas are expected to be anywhere from a trace to a tenth of an inch so slippery roads and surfaces, not tree damage or power outages, are expected. A few patches of freezing rain in the Bangor region cannot be ruled out but seem unlikely given the more southern trend of the storm track.

Will have to closely watch temperatures this morning over the coastal Downeast area. Current guidance suggests that temperatures may stay at or below freezing north of Route 1 through mid-day allowing freezing rain to hold on there while a changeover to plain rain is expected along the immediate coast by mid-morning. Thus, have extended the winter weather advisory in those regions.

KEY MESSAGE 2...

Patchy freezing drizzle ahead of precipitation Friday morning and freezing drizzle behind cold front late Friday night

KEY MESSAGE 2 DESCRIPTION... Warm front will lift through the region on Friday afternoon. Isentropic lift on Friday morning will bring patchy freezing drizzle just ahead of the steadier precipitation. Warm front lifts through with temps climbing above freezing after a brief period of light snow at onset. All told expect a glaze of ice and a dusting of snow before becoming all rain in the afternoon.

Following fropa late Friday night low levels will remain briefly saturated with sfc temps dipping blo freezing and another possibility for patchy freezing drizzle across the north.

KEY MESSAGE 3...

Potential Winter Storm Saturday Night and Sunday

KEY MESSAGE 3 DESCRIPTION... Upr low digging into the upper Midwest will dive twd the Great Lakes Saturday night. Precip will be slow to move in from the southwest as blyr remains dry courtesy of ridge axis over the area. Onset of precipitation will be determined by how quickly ridge axis builds into eastern Canada, as well as how fast temps can drop before clouds move in.

Cold air damming is being shown late Saturday night. As of this time there are hints of a triple point developing along the coast Sunday morning. For the time being have gone with a rain/snow mix though signs are pointing to snow beginning at onset before transitioning to a sleet or freezing rain mix Saturday night into Sunday morning, mainly over central locations. Depending on how far north the triple point can develop will determine whether the north stays all snow. Winds behind the system could bring blowing snow to some of the region Sunday night and Monday.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

Wednesday: IFR at HUL/CAR/PQI/FVE throughout the day with -SN. LIFR possible at times. IFR/LIFR at BGR/BHB this morning with -RASN, improving slightly to IFR late this afternoon as precip tapers off. -FZRA possible at BHB through about 14z with confidence high enough to include it in TAF. Lower confidence in some temporary -FZRA at BGR through mid-day and thus did not include in TAF. Light N/NE winds around 5 kts. Light N/NE winds around 5 kts.

Wednesday night: BGR and BHB should improve to MVFR first, and possibly VFR late, with HUL/PQI/CAR/FVE likely to improve to MVFR around midnight but could potentially hold on to IFR conditions through much of tonight. N/NW winds around 5 kts.

Thursday: MVFR possible early at northern terminals then VFR. W/NW winds 5 to 10 kts.

Thursday night...Mainly VFR. Light WSW winds.

Friday-Friday night...MVFR/IFR. Freezing drizzle possible Friday morning with patchy fog and mainly rain on Friday. S 5-15kts Friday becoming W 10-20kts late Friday night. LLWS possible.

Saturday...Mainly VFR. WNW 5-15kts.

Saturday night-Sunday...MVFR/IFR in wintry mix. ENE 5kts Saturday night, becoming S-W 5-10kts Sunday afternoon.

MARINE

Today through Thursday... Winds and seas below small craft criteria today before seas increase to just above criteria tonight through early Thursday afternoon on all waters. Winds generally below small craft criteria through the period but may approach SCA levels tonight on the outer waters.

Thursday night through Sunday: Winds below small craft levels through Friday morning before increasing from the southwest in the afternoon. Winds likely to be marginal gales over the outer waters Friday evening before diminishing Saturday morning. Winds late in the weekend will be dependent on track of surface low over the waters. Seas look to remain under small craft levels through Friday morning before increasing in southerly swell. Expect seas to remain aoa SCA through the day on Saturday before briefly diminishing Saturday night, possibly becoming elevated again on Sunday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Winter Weather Advisory until 3 PM EST this afternoon for MEZ015>017-029-030. MARINE...None.