10:01 PM AST Sunday 11 February 2024
Winter storm forecast to pass south of Nova Scotia late Tuesday and early Wednesday.
Potential snowfall accumulations: 20 to 30 cm by noon Wednesday.
Maximum wind gusts: northerly 60 to 70 km/h giving areas of blowing snow.
Location: most of Nova Scotia.
Time frame: spreading across the province from Tuesday afternoon to Tuesday evening. Conditions improving from west to east on Wednesday.
Remarks: Forecast guidance is beginning to give a clearer picture regarding a nor'easter passing south of the province mid-week. At this time, the most likely scenario appears to be 20 to 30 cm of snowfall accumulation for most of the province by noon Wednesday. Any fresh snow from this system has the potential to combine with strengthening northerly winds to reduce visibilities in blowing snow.
As with all nor'easters, small changes in the storm track can result in large changes in the snowfall forecast, and this alert will be updated periodically to reflect the latest information.
Behind this system, a prolonged period of onshore flurries and snow squalls looks likely develop over portions of northeastern mainland Nova Scotia and northern Cape Breton, and these areas could continue to see accumulating snow into Thursday night.
Rapidly accumulating snow could make travel difficult over some locations.
Public Safety Canada encourages everyone to make an emergency plan and get an emergency kit with drinking water, food, medicine, a first-aid kit and a flashlight. For information on emergency plans and kits go to getprepared.gc.ca.
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 120220
AFDCAR
Area Forecast Discussion
National Weather Service Caribou ME
920 PM EST Sun Feb 11 2024
.SYNOPSIS...
A cold front will cross the region through tonight. 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. High pressure builds in Thursday through Friday.
&&
.NEAR TERM /THROUGH TODAY/...
9:20PM Update...There is a cold front now entering the St. John
Valley and pushing SE. Cold air advection is developing in the
wake of the front. Webcams and observations indicate 1 mile
moderate wet snow falling in Frenchville and other areas of the
St. John Valley. Expecting snow showers to continue developing
along and ahead of this front as it drifts south. Temperatures
will begin falling below freezing, this combined with very cold
subsurface temperatures...frost depth 13 inches here at the
office...will result in slick conditions in Northern Aroostook
County. Have issued an SPS to handle the concern of slick travel
conditions developing tonight. Otherwise, mainly low clouds
across the North, mainly north of Baxter region. Higher clouds
passing through across southern zones with some areas of clear
skies. Expecting a general trend of partly cloudy skies south
and mainly cloud north. Minor tweaks to the temps and dew points
based on the observational trends.
Previous Discussion...
Deep layered westerly flow aloft will persist tonight through
Monday. A cold front will cross northern areas tonight, and then
cross the remainder of the region early Monday.
The guidance for the past many cycles has been suggesting a
northwest to southeast oriented band of snow showers developing in
the wake of the cold front for northern areas. The CMC regional has
led the way highlighting this. Have been monitoring the latest
several runs of the HRRR today and it continues to suggest a
band developing across northern Aroostook county through early
this evening before waning overnight. This could result in
localized accumulations of an inch or two in some parts of the
county into this evening.
The modest cold advection behind the front should still allow
overnight lows across the north to drop a good 10 degrees colder
that last nights, but still several degrees above the normals
for this time of year.
West to northwest flow persists on Monday with mainly cloudy
skies north along with isolated to scattered snow showers, and
partly cloudy for Bangor and Downeast. Afternoon highs on Monday
will be a good 5 to 10 degrees cooler than those of todays.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
Synoptic: A low pressure system will move up through the Mid-
Atlantic states and track off the southern New England coast
Monday night into early Tuesday morning. This low will deepen as
it travels eastward, continuing to strengthen as it crosses
south of the Gulf of Maine and Nova Scotia and pushes out into
the North Atlantic.
Model Guidance: Recent guidance has come into better agreement
with the northern extent of the precip shield, with the ECMWF
trending southwards slightly and the last couple runs of the CMC
moving steadily northwards to meet the GFS solution in the
middle. This agreement has only just been realized with the 12z
runs, but gives better confidence (50 to 60%) of where will
receive measurable snowfall (primarily the Downeast region,
especially along the immediate coast).
Threats:
-Most snowfall is expected along the immediate coast, with
current forecast being a chance (50%) of around 3 to 5 inches.
This accumulation is largely dependent on the exact low track,
as there is a steep gradient to the north where snowfall drops
to zero, so any shifts in low track by a few miles could lead
to amounts increasing or decreasing from here. Measurable
snowfall will likely not begin until Tuesday afternoon, as a
layer of mid-level dry air between 800 and 600 mb will need to
saturate prior to accumulating snowfall onset.
-Winds will remain breezy during the event itself, but will
rapidly increase behind the low passage Tuesday night into
Wednesday, where gusty winds up to 30 mph will persist. Since
snow will be of fluffier consistency, especially through the
second half of the event with SLRs approaching 20:1, there
could be some patches of blowing and drifting snow through the
day on Wednesday.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
A ridge of high pressure will return through the end of the
week, with a tight pressure gradient aloft Wednesday night
persisting gusty winds, but this gradient will relax into the
day on Thursday as the high pressure continues to further
establish. A weak warm front may lift across the area on Friday,
bringing a few snow showers across the area, but there remains
timing and strength uncertainty across guidance at this time
with this feature........
Hazardous Weather Outlook
National Weather Service Caribou ME
342 PM EST Sun Feb 11 2024
MEZ029-030-122045-
Coastal Hancock-Coastal Washington-
342 PM EST Sun Feb 11 2024
This Hazardous Weather Outlook is for Coastal DownEast Maine.
.DAY ONE...This afternoon and tonight.
Hazardous weather is not expected at this time.
.DAYS TWO THROUGH SEVEN...Monday through Saturday.
A coastal storm may bring light to moderate accumulating snow to
Coastal Downeast Tuesday into Tuesday night.
.SPOTTER INFORMATION STATEMENT...
Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.
$$
