Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/03/21
AREA FORECAST DISCUSSION
National Weather Service Albany NY
950 PM EST Tue Feb 2 2021
.SYNOPSIS...
A coastal storm will slowly move along the New England
coast overnight through tomorrow. Cloudy skies with occasional light
snow or snow showers will continue through Wednesday. Fair and
seasonably cold weather is forecast for Thursday. A cold front may
bring a period of light snow and rain on Friday.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 950 PM EST...All the winter weather advisories have been
canceled that were in effect for eastern NY. Some light snow
continues across the western Mohawk Valley, western Adirondacks,
Schoharie Valley and the northern Caskills. Additional snowfall
will be light with a dusting to a few inches in most areas. The
exception maybe across northern Herkimer County where north of
Route 28 2-4" may occur, but overall downward trends of
widespread, impactful accumulating snow is expected overnight.
The center of the closed H500 low is near the northeast
PA/northern NJ and southern NY corridor based on the RAP.
Short-wave energy continues to rotate around the closed low
which the latest water vapor imagery shows a vort max swirling
over eastern NY. The main sfc low at 987 hPa is near the Gulf of
ME. The cyclonic vorticity advection with the closed low
continues to tap some Atlantic moisture into upstate NY and
northern New England. The best coverage of snowfall on the
regional mosaic radar imagery is over northern and west-central
NY. The activity is more diffuse over eastern NY with spotty
light snow. Some locations west of the Capital Region across the
Mohawk Valley, western Adirondacks, northern Catskills and
Helderbergs could get additional snowfall tonight.
Another short-wave rotates around the low overnight bringing
some light snow or snow showers back across eastern NY into the
southern Greens and Berkshires towards 6 am. This may cause some
upslope snowfall along the northern Taconics too. We tried to
increase the PoPs towards daybreak and retool PoP trends based
on the 3-km HRRR and NAMnest.
Northerly winds continue tonight at 5-15 mph. Lows will be in
the mid teens to lower 20s with cloudy skies.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
The coastal storm will move slowly northeastward up the New
England coast reaching the Canadian Maritimes by Wednesday
evening. Our area will remain under its influence as the
associated the upper low moves slowly across southern New
England. This will keep chances for light snow and snow showers
in the forecast into Wednesday night with chances gradually
decreasing over time. Accumulations are generally expected to be
light, but with a large slow moving cutoff low, there are
always surprises. Winds will become northwesterly tonight and
remain brisk and gusty through the day Wednesday.
Lows tonight in the teens to mid 20s. Highs Wednesday in the
mid 20s to lower 30s. Colder Wednesday night with lows mainly
between 10 and 20 degrees.
As the low pulls away on Thursday, a weak high pressure ridge
builds across the area, and skies are forecast to clear. A fair
and tranquil late winter day is expected with highs mainly in
the 30s, although cooler in the highest terrain. Thursday
evening remains tranquil, and with fresh snowpack, mainly clear
skies and light winds, good radiational cooling should help
temperatures drop off fairly quickly. Clouds begin to increase
after midnight as a cold front approaches the area. Lows
Thursday night mainly in the teens.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Active weather pattern continues through the long term, with best
chances for impactful winter weather Friday, then again possibly
Sunday-early Monday.
Initial system approaches from the Great Lakes region Friday, with
strong surge of mid level warm advection. Thermal profiles suggest P-
type may start as snow, or a snow/sleet mix in many areas Friday
morning. Then, boundary layer warming should allow for P-type to
become mainly rain, or a rain/snow mix in valley areas near and
south of I-90 for the afternoon, with precipitation possibly
becoming more showery/spotty for these areas. North of I-90,
steadier precipitation may continue into the afternoon, and enough
wet bulb/dynamical cooling should support mainly snow, perhaps
mixing with rain before precipitation tapers off in valley areas.
Mainly light snowfall amounts are expected (perhaps a coating to 2
inches), although higher terrain of the Catskills, SW Adirondacks,
and portions of the Mohawk Valley and Lake George region could have
2-5 inches, which may eventually prompt the issuance of some
advisories. Timing currently looks to be mainly mid morning through
early/mid afternoon, however will have to watch in case
precipitation develops a bit sooner, which could then affect
portions of the morning commute.
A brief reprieve expected Friday night-Saturday night, although some
Lake Effect and upslope snow showers could occur through Saturday
across portions of the SW Adirondacks and southern VT.
Then, the threat for a more highly impactful storm system exists for
Sunday-early Monday, although considerable uncertainty remains in
the details, with the 12Z/02 GFS and mean of the GEFs suggesting a
track well offshore with less phasing between northern/southern
stream features, however an arctic front may bring snow showers or
snow squalls to the region during this time. The 12Z/02 ECMWF, on
the other hand, continues to depict a stronger storm system with
northern/southern stream phasing and a track much closer to the
coast. Should this prove correct, a highly impactful winter storm
would occur across much of eastern NY and western New England. At
this time, have kept high chance PoPs Sunday-early Monday across the
region, and trends will have be watched in case a more
phased/stronger storm system affects the region during this time
period.
Regardless of the exact outcome with this potential storm system for
Sunday-early Monday, well below normal temperatures and Lake Effect
snow look likely for late Monday into Tuesday, with the possibility
for significant Lake Effect snow across portions of the SW
Adirondacks (especially northern Herkimer/western Hamilton Counties).
As for temperatures, highs Friday mainly in the mid 30s to lower
40s, although portions of the southern Adirondacks may only hold in
the lower/mid 30s. Friday night lows in the teens to lower 20s.
Highs Saturday-Sunday mainly in the mid 20s to lower 30s, with
Saturday night/Sunday morning lows in the single digits and teens.
Much colder for Monday-Tuesday, with highs mainly in the teens to
lower/mid 20s; although could actually be even colder. Overnight
lows should range in the single digits above and below zero, with
some colder min temps possible across the southern Adirondacks. Wind
chills may drop into the 10 to 20 below zero range for at least
higher elevations Monday night.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
Disturbances rotating around a nearby upper level low pressure
system will bring some snow showers and flurries to the TAF
sites overnight into Wednesday.
Mainly MVFR conditions (mainly for Cigs) are expected overnight
into Wednesday morning. A few periods of MVFR/IFR Vsbys will be
possible through 02Z/Wed as some snow showers pass through.
MVFR Cigs may lift to VFR at some TAF sites Wednesday
afternoon, as ceilings lift to between 3500-4500 FT AGL.
However, as another upper level disturbance passes through, some
snow showers or flurries will be possible roughly between 14Z-
20Z/Wed. Brief periods of MVFR/IFR Vsbys could occur within any
more formidable snow showers.
Winds will become north to northwest tonight at 5-10 KT,
although some gusts of 20-25 KT will be possible at KPOU this
evening. On Wednesday, winds will become northwest to west and
increase to 8-12 KT, with gusts of 20-25 KT possible.
Outlook...
Wednesday Night: Low Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: High Operational Impact. Breezy. Likely RA...SN.
Friday Night: Low Operational Impact. NO SIG WX.
Saturday: No Operational Impact. NO SIG WX.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: Moderate Operational Impact. Chance of SN.
&&
.HYDROLOGY...
No widespread hydrological issues are expected for the next week.
Daily average temperatures are forecast below freezing through
the next week which will lead to an increase in river ice.
Precipitation will generally be in the form of snow leading to
an increase in the snow pack.
For details on specific area rivers and lakes, including
observed and forecast river stages and lake elevations, please
visit the Advanced Hydrologic Prediction Service /AHPS/ graphs
on our website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...SND/Wasula
NEAR TERM...Wasula
SHORT TERM...SND
LONG TERM...KL
AVIATION...KL/Rathbun
HYDROLOGY...SND
Area Forecast Discussion
National Weather Service Bismarck ND
929 PM CST Tue Feb 2 2021
.UPDATE...
Issued at 929 PM CST Tue Feb 2 2021
Not seeing too many issues with dense fog just yet, with all
observations reporting at least a mile of visibility, so will
hold off on an advisory with this update. Made adjustments to sky
cover based on slow westward expansion of the low stratus deck,
seen on nighttime satellite imagery.
The cold front that will be moving through the forecast area
tomorrow is located in southern Saskatchewan, per the latest
surface analysis. No change in our thinking regarding
precipitation type and timing tomorrow as the cold front moves
through during the day. Still a chance for some freezing rain on
the leading edge of precipitation, and for some freezing drizzle
in the James River Valley tomorrow afternoon and evening.
Otherwise precipitation is expected to be primarily snow, with
generally less than an inch of accumulation expected.
Accumulations of 1 to 2 inches are possible in the north central.
UPDATE Issued at 607 PM CST Tue Feb 2 2021
Southwest North Dakota was the place to be today, with mostly sunny
skies and high temperatures reaching the upper 50s. Dickinson
even set a new record high of 58 degrees, breaking the old record
of 55 set in 1962. Meanwhile, low stratus has persisted across the
central part of the state, with Bismarck not even reaching above
freezing.
We went ahead and expanded areas of fog through much of the south
central and James River Valley from now, through the night, and
into tomorrow morning. NDDOT travel cameras at Ashley and Medina
are already showing fog, and Carrington, Jamestown, and Oakes are
all reporting reduced visibilities. Would not be surprised to see
visibilities continue to drop as they have the past few nights,
since the same air mass is still in place.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 215 PM CST Tue Feb 2 2021
The short term period is highlighted by a cold front arriving
Wednesday, bringing light snow, breezy northwest winds, and some
mixed precipitation with a chance of freezing drizzle in the James
River Valley.
Synoptic pattern this afternoon was characterized by a broad ridge
axis from southern Ontario through North Dakota. At the surface a
low was over southern Saskatchewan, along with an accompanying
cold front. A warm front aloft had pushed across the central, with
those in the west with sunny skies and little snowpack seeing the
warmest temperatures this afternoon. Satellite loops show stratus
slowly eroding eastward with dry westerly flow just above the
shallow saturated boundary layer. RAP 925mb relative humidity
fields keep saturation in the south central through east, which
seems reasonable for continued cloud cover and the possibility for
reduced visibilities again tonight.
Southwest flow and DCVA takes over on Wednesday with the surface
low and cold front arriving in the west. A potent warm nose
aloft, centered at about 850mb, will take time to erode and may
cause initial precipitation to have some pockets of freezing rain
mixed in. Confidence in this at any location is low however with
forecast soundings showing only a very brief window for this
possibility with initial soundings being very dry for
precipitation before cooling and saturation. Thus we have
predominantly snow as the weather type for most of the area. The
exception being the southern James River Valley tomorrow
afternoon and evening where antecedent low level moisture and
modest omega may overlap to produce freezing drizzle. With the
progressive wave and front, snow amounts should be light, less
than an inch in most areas. Across the north central where better
DCVA and brief low level frontogenesis line up, one to two inches
are possible.
.LONG TERM...(Thursday through Tuesday)
Issued at 215 PM CST Tue Feb 2 2021
The long term period is highlighted by dangerously cold wind
chills forecast this weekend.
Thursday will begin a period of reinforcing cold post-frontal air
masses as Arctic air arrives through the weekend. A low level
baroclinic zone will set up from northwest to southeast, gradually
pushing south across southwest North Dakota as colder air fills in.
With this setup, temperatures should be warmest in the southwest and
coldest in the northeast. Friday through this weekend, a series of
shortwaves embedded in the northwest flow will ride over the
baroclinic zone, delivering shots of light snow to the west. The
worst of the Arctic air mass still looks to set up Saturday and
Sunday, with 850mb temperatures over 2 standard deviations below
climatological mean. GEFS/ECMWF ensembles show healthy probabilities
of -30 C 850mb temperatures by Sunday morning, especially across
the north. This will deliver surface temperature lows, and
certainly wind chills, well below zero across the area. Northern
tier counties may reach wind chills of around 45 below zero Sunday
morning and Monday morning, depending on how cloud cover sets up.
Next week`s temperature outlook becomes a little murky, with 00/12Z
deterministic guidance straying from the means. GEFS/ECMWF ensemble
mean offers a gradual rebound, along with the NBM. 12Z ECMWF
deterministic does want to bring another cold shot mid-week, though
based on ensemble spread this is currently on the low end of the
probabilistic envelope.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 607 PM CST Tue Feb 2 2021
IFR to LIFR ceilings continue at KBIS and KJMS, and are expected
to persist through the 00Z TAF cycle. VFR conditions at
KDIK/KXWA/KMOT through 12Z, with a cold front entering northwest North
Dakota after 12Z. Expect initial MVFR conditions along the front,
with light snow possible, before IFR ceilings move in after the
front passes. Breezy northwest winds will also accompany the
frontal passage.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MJ
SHORT TERM...AE
LONG TERM...AE
AVIATION...MJ
Area Forecast Discussion
National Weather Service Caribou ME
1017 PM EST Tue Feb 2 2021
.SYNOPSIS...
Low pressure will track northeast into the Maritimes through
Wednesday. The low will then exit across the Maritimes
Wednesday night into Thursday. High pressure will cross the
region Thursday night. A warm front will approach later Friday,
with an occluded front crossing the region Friday night into
Saturday. Low pressure could begin to approach later Sunday.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
1010 PM Update:
Steady precip across the coastal areas has ended for the most
part. Some spotty rain showers or snow showers are still
possible overnight. Temps continue to slow warm along coast and
that warmer air is slowly working its way inland. Decided to
cancel the Winter Storm Warning for the coast and central
Washington County. The rest of the headlines remain as is for
now. BGR has climbed to 32F with snow mixed w/sleet at times.
Upper 20s to lower 30s across northern and central areas. The
warm layer between 850-700 has worked its way into Northern
Maine with Caribou and Presque Isle reporting sleet. The radar
shows the sleet well in Dual Pol mode working to the n. Cannot
rule out some -FZRA mixing in at times overnight as depicted by
the latest RAP and NAM soundings. The -FZRA could makes it way
into NE Aroostook County overnight w/a light ice coating
possible.
Previous Discussion...
Coastal low was near the Bay of Fundy per the latest sfc
analysis. Temps have jumped into the low/mid 30s w/rain being
reported right along the outer islands and up into the eastern
tip of coastal Washington County(Eastport at 36F). However, snow
was occurring further inland along the coast mixed w/-FZRA at
times. The latest radar showed broken bands of precip lifting
across the region w/snow- sleet across northern areas, and some
light -FZRA across the Maine Central Highlands. Abbot in
Piscataquis County reported FZRA last hr. The latest forecast
doing fairly well w/rain edging its way to the coast, while
sleet has made its way into northern Maine, and as far n as the
St. John Valley. Tweaked the hrly temps/dewpoints to bring
things to the current conditions. Decided to keep the headlines
where they are for now. Even though rain was occurring along the
outer islands and into the Eastport area, cold temps at the sfc
could allow for rain to freeze. Will re-evaluate the headlines
around 9 PM.
Previous Discussion...
Hvy snow continues acrs the north but warm temps aloft are
quickly closing in just to the north of HUL and would not be
surprised if area of sleet stays just east of the Route 1
corridor in nern Aroostook, strictly based on 800-700mb temps fm
18z NAM. This field seems to serve as the best proxy for
sleet/fzra line and hv based wx grids on this.
Storm total accums have not changed significantly acrs the area,
tho did bump accums up by an inch or two acrs the north with
band that went thru earlier and also the expectation of more
bands developing given frontogenetical frcg expected into the
evng hrs.
Expect that snow will rmn acrs the northwest thru the day
tomorrow as upr lvl trof continues to work it`s way east thru
Canada. Upr lvl ridge will be building in fm the west on Wed
evng at the tail end of the near term pd.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
The surface low slowly exits across the Maritimes Wednesday night,
with upper level low pressure remaining across the region. Expect a
chance of snow showers across the north and mountains Wednesday
night with light additional accumulations possible. Expect
decreasing snow showers Downeast. The upper low remains across the
region Thursday. Expect skies will remain mostly cloudy across the
north and mountains Thursday along with decreasing snow shower
chances. Across Downeast areas, expect mostly cloudy skies along
with a slight chance of snow showers early Thursday then decreasing
clouds during the afternoon. The upper low drifts east across the
Maritimes Thursday night, while high pressure builds across the
region at the surface/aloft. Expect mostly/partly cloudy skies
across northern areas Thursday night, with generally partly cloudy
skies Downeast. High pressure will exit across the Maritimes early
Friday. Low pressure lifting across the Great Lakes will draw a warm
front toward the region later Friday. Clouds will increase early
Friday. Overrunning warm advection precipitation will then expand
across the region through the afternoon. Generally expect
precipitation in the form of snow across much of the region Friday
afternoon. However, a snow/rain mix could develop Downeast
particularly near the coast. Temperatures will be at above normal
levels Thursday/Friday.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Low pressure could develop along the occluded front crossing the
region Friday night. Precipitation will remain in the form of
accumulating snow across northern areas Friday night, though snow
totals are still uncertain. A snow/rain mix is expected Downeast
Friday night. The low exits across the Maritimes early Saturday.
Could still have a chance of snow or snow showers across the north
and mountains early Saturday with the exiting low, with decreasing
snow shower chances during the afternoon. Snow/rain shower chances
will decrease Downeast early Saturday. High pressure should cross
the region early Sunday. Low pressure should develop south of the
region later Sunday. Uncertainty exists later Sunday through Monday
regarding the track and intensity of the low. Precipitation
chances, types and amounts with this potential system will be
dependent on the eventual track and intensity of the low. The
system should exit across the Maritimes Tuesday, with an upper
level trof remaining across the region. Expect partly/mostly
cloudy skies north with possibly a slight chance of snow
showers, partly cloudy Downeast, Tuesday. Expect above normal
level temperatures Saturday/Sunday, with the warmer
temperatures Saturday. Near normal, to slightly above normal,
level temperatures are expected Monday. Below normal level
temperatures are expected Tuesday.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: LIFR for northern terminals in moderate snow becoming
IFR after 06z at KFVE and after 23z at KCAR, KPQI and KHUL.
KHUL begin to mix with sleet after 23z and maintain -snpl
through Wed morning.
Downeast terminals will see IFR sleet into this evening, before
mixing with -fzra at BGR and -ra at BHB. Expect IFR cigs through
remainder of TAF forecast.
LLWS from the ENE at FL020 between 45-60kts this afternoon,
diminishing this evening at srn terminals and after midnight
across the north.
SHORT TERM:
Wednesday night...MVFR/IFR with a chance of snow showers.
North/northwest winds 10 to 15 knots.
Thursday...MVFR/VFR north with a chance of snow showers. MVFR/VFR
with a slight chance of snow showers early Downeast, then VFR during
the afternoon. North/northwest winds 10 to 15 knots.
Thursday night...VFR/MVFR north, VFR Downeast. Light winds.
Friday...VFR early, MVFR late with a chance of snow north and a
chance of snow/rain Downeast. Light winds early, then
south/southeast 10 to 15 knots.
Friday night...IFR/LIFR. Snow north. Snow, or a snow/rain mix,
Downeast. Southeast winds 10 to 15 knots early, becoming
west/northwest late.
Saturday...MVFR/IFR early, VFR/MVFR late. A chance of snow early
mostly north. West winds 15 to 20 knots with gusts to around 25
knots.
Saturday night...VFR/MVFR north and mountains, VFR Downeast. West
winds 15 to 20 knots early then decreasing.
Sunday...VFR early, then uncertainty late.
&&
.MARINE...
NEAR TERM: Update...Winds still gusting AOA 35 kt over the outer
zones, but the trends have been for the winds to drop back with
the next few hrs. Decided to let the Gale Warning expire, and
issued a Small Craft Advisory w/winds 20-30 kt sustained. A few
gusts to 35 kt still possible for the next few hrs.
Previous Discussion...
Winds likely to drop blo gales within the next 1-2 hrs and
below SCA levels shortly bfr midnight. However, seas will remain
elevated thru the day on Wed.
SHORT TERM: Small craft advisory conditions are expected Wednesday
night into Thursday night, then again later Friday. A slight
chance of snow/rain showers Wednesday night. A chance of
rain/snow later Friday.
&&
.TIDES/COASTAL FLOODING...
Storm surge of over 1 1/2 feet is still expected with the high
tide near 130am tonight, but with a relatively low astronomical
tide, coastal flooding is not expected. In terms of wave runup,
some minor overwash is possible on Seawall Road and other
vulnerable spots on Mount Desert Island and the Schoodic
Peninsula, but wave heights are expected to decrease
significantly compared to this afternoon`s high tide. As a
result, will not be issuing any coastal headlines at this time.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Winter Storm Warning until 7 AM EST Wednesday for MEZ001>005-
010-031.
Winter Storm Warning until 2 AM EST Wednesday for MEZ006-011-
015-016-032.
MARINE...Small Craft Advisory until 4 PM EST Wednesday for ANZ050>052.
&&
$$
Near Term...Hewitt
Area Forecast Discussion
National Weather Service Cheyenne WY
523 PM MST Tue Feb 2 2021
.SHORT TERM...(This evening through Thursday)
Issued at 205 PM MST Tue Feb 2 2021
Mild temperatures this afternoon with several locations over the
far eastern Wyoming plains and western Nebraska panhandle near 65
degrees this afternoon. High temperatures may approach 70 for
locations like Scottsbluff and Sidney before the higher clouds
begin to move in. Pleasant temperatures observed further to the
west with readings in the upper 50s to near 60 around Cheyenne and
Douglas, and upper 40s west of the Laramie Range.
Tricky wind forecast for tonight as models continue to show the
next cold front pushing into far western Wyoming with relatively
mild temperatures along and east of the I-25 corridor. 700mb winds
are a little stronger compared to this time yesterday with values
approaching 55-60 knots late tonight and into early Wednesday.
However, near surface gradients do not look too impressive; but
can`t ignore the mountain wave potential with all models showing a
signature signal for mountain wave activity, which you can already
see on Visible Satellite this afternoon. Felt comfortable enough
to upgrade the High Wind Watch to a Warning for the Arlington/Elk
Mountain zone starting at 11 pm tonight. This is a conditional
forecast so it`s not 100% certain at this point, but the
Arlington/Elk Mountain area has the best potential to see gusts
over 58 mph from both the mountain wave activity and frontal
passage. Kept the High Wind Watch going for the central & southern
Laramie Range including the Bordeaux area mainly due to less
confidence. May need to keep these watches going through tonight
since short-fused warnings are the best approach in this
situation. Stronger winds can`t be ruled out for other areas along
the I-25 corridor and the Laramie Valley as well, but confidence
is pretty low at this point.
For Wednesday through early Thursday, models continue to be in
good agreement both on run-to-run consistent and compared to
others. Cold front will quickly push southeast across the region
and into Carbon and Converse county between 900 AM and noon, with
timing closer to the late afternoon/evening hours towards the
southern Nebraska panhandle. Snow will quickly develop across the
mountains tonight, but is not expected to reach the high valleys
and eastern plains until early morning (high valleys west of
I-25), and late afternoon/evening for the eastern plains. Some
rain is possible at the onset with the HRRR showing some
convective elements across the Nebraska panhandle late Wednesday
afternoon. Current snow forecast remains on track with only minor
updates made today. Both mountain zones look good with some north
and west facing slopes/ridges likely seeing a foot of snow by noon
Thursday. Went ahead and upgraded the Winter Storm Watches to
Warnings for both locations with the higher elevations and peaks
seeing around 10 to 15 inches of snow. Much lower amounts as you
head into the valleys and high plains since downslope
winds/subsidence behind the front will be tough to overcome.
Generally, kept snow accumulations up to one inch for the lower
elevations with a few exceptions. The northern panhandle over the
Converse county in addition to portions of the Laramie Valley may
see slightly higher amounts due to favorable upslope north to
northwest winds behind the cold front late Wednesday night.
However, the cold front and associated upper level trough will be
very progressive, so some moderate to heavy snowfall will likely
be pretty brief. May see around 2 inches of snow for these
locations. High resolution models are favoring the north faces
slopes of the northern Snowy Range, so issued a Winter Weather
Advisory for the Elk Mountain/Arlington area and made it valid
just after the High Wind Warning expires as impacts will switch
from high winds to falling/drifting snow through early Thursday
morning. Conditions are expected to improve by Thursday afternoon
with decreasing clouds, but isolated snow showers and cold
temperatures will remain over the area.
.LONG TERM...(Thursday night through Monday)
Issued at 300 AM MST Tue Feb 2 2021
Brief break in the weather Friday before the next upper shortwave
dives southeast out of Canada and across the region by late
Friday. This will bring a surge of colder arctic air in its wake
with some upslope snows mainly Friday night into Saturday. Right
now snowfall amounts not looking too heavy as moisture is somewhat
limited as well as dynamics. After that the arctic boundary may
slip a little northeast Sunday before the next weak impulse drops
across and pushes the boundary back sw again Monday. Temps will be
a bit tricky as a result. Some light snow possible again mainly
over the northern part of the CWA Monday closer to where the
boundary will exist.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 515 PM MST Tue Feb 2 2021
VFR under FEW to SCT high ceilings and west to northwest winds
gusting to 25 kts west of the Laramie Range. Increasing and
lowering clouds overnight ahead of winter weather. -SHSN will
begin west to east after 03/06Z, first across the mountains and
KRWL, spreading east by the afternoon, with increasing gusts
across the Plains. MVFR/IFR conditions are likely by the end of
the TAF period, and sooner at KRWL. LIFR is possible as well,
especially in BLSN. Mountain obscuration likely.
&&
.FIRE WEATHER...
Issued at 205 PM MST Tue Feb 2 2021
Minimal fire weather concerns this week. The very dry airmass over
portions of the area will continue into this evening as moisture
begins to increase in the boundary layer. Humidities will trend
much higher over the next few days as a strong Pacific cold front
moves across the area on Wednesday. Much colder temperatures, high
relative humidities, and several chances for accumulating snow are
expected beginning Wednesday afternoon and continuing through the
weekend.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Storm Warning from 11 PM this evening to 11 AM MST
Thursday for WYZ112-114.
High Wind Warning from 11 PM this evening to 5 PM MST Wednesday
for WYZ110.
Winter Weather Advisory from 5 PM Wednesday to 9 AM MST Thursday
for WYZ110.
High Wind Watch from 2 AM MST Wednesday through Wednesday
afternoon for WYZ106-116-117.
NE...None.
&&
$$
SHORT TERM...TJT
LONG TERM...RE
AVIATION...AB
FIRE WEATHER...TJT