Saturday, February 10, 2024

Winter Storm Lorraine/Valentine's Day Nor'easter























9:42 PM AST Saturday 10 February 2024

Potential winter storm mid week.

Environment Canada meteorologists are monitoring the potential development of a Nor'easter passing south of Nova Scotia Tuesday into Wednesday. It is too early to make a prediction of snowfall amounts, as the forecast track remains very uncertain. Regardless of the eventual scenario, a period of onshore flurries and snow squalls is likely to develop over northern Cape Breton behind the system later in the week.

We will share additional details as they become clear, and our messaging related to this system may be escalated in the coming days.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to NSstorm@ec.gc.ca or tweet reports using #NSStorm.


000
FXUS61 KCAR 110338
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
1038 PM EST Sat Feb 10 2024

.SYNOPSIS...
Low pressure will track well to our north through Sunday. A
cold front approaches Sunday and crosses the region through
Sunday night. Low pressure will organize along the mid atlantic
on Monday, move south of the area on Tuesday, and exit into the
north Atlantic on Wednesday.

&&

.NEAR TERM /THROUGH TODAY/...
1037 PM Update: Patchy fog conts msly ovr Cntrl/Downeast and
parts of NE ME; areas that experienced shwrs this prior Late
Aftn into Erly Eve or melting snow, xpctd to last thru the
remainder of the Late Eve with initial lgt and vrbl winds with
the occluded front passage. Deeper llvl WNW winds later tngt
should dissipate fog with slightly drier air arriving from QB.
Otherwise, latest obsvd temps/dwpts were used to update fcst
hrly temps/dwpts into the late ngt hrs with nearly steady temps
and little or no chgs to fcst ovrngt low temps attm.

Prev Disc: Expect another mostly cloudy and unseasonably mild
night tonight. Lows are only expected to fall into the lower 30s
for most areas. Sunday is another unseasonably mild day ahead
of the approaching cold front. Guidance continues to suggest the
potential for Northwest to southeast oriented streamers with
the cold front later Sunday afternoon. Highs on Sunday will be
in the mid to upper 30s north and lower 40s for bangor and
Downeast.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY/...
Sunday night into Monday there will be an inverted trough set up
over northern Aroostook county, which will provide just enough
instability for snow showers to linger across the north through
Monday afternoon. With only light moisture advection through
this time, showers may provide up to an inch of total snow
accumulation, but only in areas where snow showers train behind
one another.

The main player through the short term will be a low pressure
system passing south of the forecast area Tuesday into Tuesday
evening:

-Great uncertainty remains across deterministic models in low
 track, with Canadian guidance suppresses the precip shield well
 south of the Gulf of Maine and Nova Scotia, and the 12z ECMWF
 came in with the low deepening enough for precip to make it
 into southern Aroostook county. What is consistent across
 deterministic guidance is that the low has trended slower with
 each run, crossing our longitude late Tuesday afternoon into
 Tuesday evening.

-Forecast soundings across all guidance show a layer of dry air
 between 850 and 600 mb that will delay measurable precip onset
 while this layer begins to saturate as the storm approaches.
 Even the 12z ECMWF shows this layer, but saturates it more
 quickly than all other guidance. With northeasterly to
 northerly mid level flow during this time, it is unlikely for
 this layer to saturate very quickly, and so the solution in
 this forecast package leans towards the NBM and GFS guidance
 for precip onset and northern extent of measurable precip, with
 the northern extend ending around northern Washington and
 central Penobscot and Piscataquis counties. Due to the dry
 layer aloft, a drizzle/flurries profile results, and so
 flurries were added to the northern extent of stratiform precip
 as the storm crosses the area.

-Storm total snowfall amounts greater than an inch Winds and
 seas will remain below SCA criteria through Monday but increase
 to SCA through the day on Tuesday with a storm passing south of
 the Gulf of Maine. Northerly winds may approach low end gale
 strength Tuesday night through Wednesday night, while seas peak
 around 5 to 7 ft.are currently forecast to remain along the
 immediate coast, with a sharp decrease in total snowfall across
 Interior Downeast.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The low pressure exits to the west Tuesday night, and continues
to deepen as it moves out into the North Atlantic. This will
result in a tightening pressure gradient aloft over the forecast
area, which will lead to gusty winds through the middle of the
week.

Generally unsettled weather is expected through the end of the
week, as an upper level trough remains over the area and a
shortwave approaches from the west through the end of the week.
Though timing and strength remains uncertain with this next
system, there could be some snow showers across the area through
the end of the week. Temperatures will be around average for
this time of the year through the end of the week, with lows a
few degrees above normal with lingering winds and overcast skies
reducing the chance for radiational cooling.......


Hazardous Weather Outlook...CORRECTED
National Weather Service Gray ME
415 PM EST Sat Feb 10 2024

MEZ012>014-018>022-033-NHZ004>013-015-112115-
Southern Oxford-Southern Franklin-Southern Somerset-Interior York-
Central Interior Cumberland-Androscoggin-Kennebec-Interior Waldo-
Interior Cumberland Highlands-Northern Carroll-Southern Grafton-
Southern Carroll-Sullivan-Merrimack-Belknap-Strafford-Cheshire-
Eastern Hillsborough-Interior Rockingham-
Western And Central Hillsborough-
415 PM EST Sat Feb 10 2024

This Hazardous Weather Outlook is for Maine, south central Maine,
southwest Maine, western Maine, New Hampshire, central New
Hampshire, northern New Hampshire and southern New Hampshire.

.DAY ONE...Tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

We continue to watch potential low pressure moving to our south on
Tuesday. Plowable snow is possible depending on low track which is
uncertain at this time. The heaviest snow would likely be across
southern New Hampshire.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

$$