Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/28/23

AREA FORECAST DISCUSSION

National Weather Service Albany NY

 934 PM EST Mon Nov 27 2023

&&

.SYNOPSIS...
A chilly air mass will be over the region tonight into
the mid week, as lake effect snow will continue across the western
Adirondacks, western Mohawk Valley and into the northern Catskills.
The heaviest lake effect snow will be tonight through Tuesday.
Additional snow showers and flurries will impact the region tomorrow
with a secondary cold front moving through, but high pressure will
build in from the Mid Atlantic States with the lake effect
decreasing by Wednesday.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
930 PM Update...
Radar trends east of Lake Ontario suggesting snowband is taking
a little longer to get established than previously thought, so
have trended QPF and resultant snow totals across northern
Herkimer and Hamilton Counties down just a bit. Still think band
will become better organized through the overnight hours with
latest scans showing less cellular appearance to returns in
northern Oswego and Lewis Counties, indicative that better
organization is beginning to take place. This should still
yield decent snowfall totals across northern Herkimer and
Hamilton Counties by morning.


630 PM Update...
Minor tweaks made to pop/wx based on radar trends from TYX radar.
Lake effect snow event becoming more firmly established this
evening as cold air advection combines with long-axis wind flow
down the length of Lake Ontario. With high equilibrium levels,
favorable lift through the dendritic snow growth region and
extreme instability, expect ongoing activity to develop more
into a single band as the evening/overnight hours progress.
Primary areas of concern overnight will be northern Herkimer and
Hamilton Counties, where several inches of snowfall is expected
by morning. Will continue to monitor and make adjustments as
necessary.

Previous discussion...

Lake Effect Snow Warning for northern Herkimer and Hamilton
Counties Wednesday...


As of 355 PM EST...A chilly air mass is impacting the forecast
area for tonight. A broad mid and upper level trough remains
over the Great Lakes Region, southeast Canada and the Northeast.
Bands of lake effect snow have developed downstream of Lakes
Erie and Ontario. The band moving across the Tug Hill Plateau
continues to organize and move into northern Herkimer and
western Hamilton Counties late this afternoon and early this
evening. The low-level inversion remains high above 8 kft AGL
on upstream soundings with moderate to extreme lake induced
instability. The 260-270 degree low-level trajectory favors
long-axis bands to form with snowfall rates of 1-2"/hr tonight.
Strong ascent intersecting the DGZ could allow for aggregating
flakes. A rumble of thunder is also possible with the extreme
instability.

Also as the previous forecast noted...documented CSTAR research
showed that a cyclonic trough, multi-lake connection, and
favorable trajectory favors a deep inland extent with a single
snow band with snow rates 1-3"/hr. Locations overnight in and
near Old Forge and Route 28 could receive 7-14" of snowfall.

Some lake effect snow showers and flurries could drift in off
Lake Erie into the northern and eastern Catskills. A few
isolated snow showers or flurries may spill eastward into the
Hudson River Valley. Light snow accums may occur on the western
spine of the southern Greens. West to southwest winds will
continue at 10-20 mph early and then be 5-15 mph overnight. It
will be chilly with lows in the 20s with some teens over the
higher terrain.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Lake Effect Snow Warning for northern Herkimer and Hamilton
Counties until midnight Wednesday...

Winter Weather Advisory for Lake Effect Snow for southern
Herkimer County from 7 AM Tuesday to 7 AM Wednesday...

No changes to the headlines here. We are monitoring if northern
Fulton Co. needs an advisory, but 2-4" looks fine for now.

Tomorrow...The lake effect machine continues with the long axis
band starting to shift southward in the morning, and then
pivoting to the southeast by the afternoon into the early
evening with a short-wave and secondary cold front. The veering
profile to the west/northwest and then northwest will allow the
band to move into the western Mohawk Valley by the afternoon
and into the evening. The transitory snow band could yield 2-6"
of snowfall. The extension into the Mohawk Valley is tricky,
but 1-4" could occur across portions of Fulton. Montgomery and
western Schenectady Counties. A few isolated heavier snow
showers or an isolated squall could occur north of I-90. Some of
of the snow showers will get into the Hudson River Valley,
Taconics, and western New England by the mid pm into the early
evening. The winds will be whipping with west to northwest winds
10-20 mph with some gusts 25-35+ mph. We did add some blowing
snow to the western Mohawk Valley. The 3-km HRRR and NAM both
show a broad range of snowfall there in the 2-6" range with the
higher totals north of I-90 we kept the advisory 7 am TUE to 7
am WED. High temps will be 10-15 degrees below normal. High will
be 30-35F in the Hudson and Mohawk Valley and and 20s to around
30F elsewhere.

The inversion will lower Tue night and the flow veers to the
northwest with multibands impacting the eastern Catskills,
Helderbergs, Mohawk and Schoharie Valleys. We could see 10-20"
of snow in the western Dacks, but winds will be whipping it all
around in a frenzy. The Capital Region Region could get a
coating to less than a half inch. A couple inches may occur in
the Berkshires and southern Greens. Lows will be in the teens to
lower 20s with a few single digits in the Adirondack Park. The
wind chills will be in the teens to slightly below zero over the
higher terrain.

Wednesday trends to tranquil, but cold conditions with some
weak warm advection ahead of the next disturbance. Additional
snow showers and flurries are possible mainly west of the Hudson
River Valley and Lake George. Any additional snow amounts will
be light. Partly to mostly cloudy conditions will prevail with
temps maybe a degree or two warmer than TUE but still colder
than normal by about 10 degrees with lower to mid 30s in the
valleys and 20s over the higher terrain.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
The extended forecast begins on a quiet note with high pressure
building in from the mid Atlantic Region over the Northeast. A
weak northern stream disturbance with weak warm advection may
produce a few flurries or snow showers over the southern
Adirondacks, but the mid level flow becomes nearly zonal, which
will allow temps to modify slightly with lower to mid 40s in
the lower elevations and mainly 30s over the higher terrain. The
sfc high will drift slowly offshore Thu night into Friday. Some
clouds may increase ahead of a cold front Thu night with lows
in the 20s and 30s.

The next chance of a widespread precipitation event will be
Friday afternoon through Friday night. A southern stream
cyclone will be lifting northeast from the lower MS River Valley
Thu night. The northern stream disturbance passes Friday across
southern Quebec with the cold front trying to move through. The
NBM/Ensembles/medium range favor a rain/snow ptype with the wet
snow mainly over the mountains north and west of the Capital
Region but we will continue to monitor the timing of the cold
front and the amount of cold air in place. Highs on Friday will
range from the mid 30s to upper 40s and PoPs were kept in the
high chance and low likely range. The system pulls away Friday
night with some weak cold advection in its wake. Lows fall into
the 30s with some 20s over the higher terrain.

The weekend looks pretty good at this rate with high pressure
building in from the Great Lakes Region and southeast Canada.
The surface high may translate eastward fast by Sunday with some
clouds thickening and lowering for isolated/scattered late day
rain/snow showers ahead of the next disturbance in the mid and
upper level southwest flow. Temps will be near to slightly above
normal. Another coastal wave in the southwest flow ahead of the
positively tilted mid and upper level trough over the CONUS
could bring a mix of rain/snow or a wintry mix Sunday night
through Monday.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Through 18z Tuesday....

Strong cold advection overspreading eastern New York and western
New England this evening following this morning`s cold frontal
passage. Main concern for the 00z forecast package involves
prospects for developing lake effect snow showers at area
terminals after daybreak, and gusty west to northwest winds
during the daylight hours as well. For now, best chance for snow
at ALB and PSF looks to be after the 18z time frame as main lake
effect band off of Lake Ontario shift south with time. This will
likely lead to periodic IFR conditions during the afternoon
hours and have included tempo groups at both locations. Activity
should remain north of POU for now, thus expect VFR conditions
through the fcst cycle. Further north at GFL, snow shower
activity may develop before daybreak with activity possibly
persisting through portions of the early afternoon as main band
shifts south with time. Overall confidence of IFR conditions at
GFL/ALB/PSF is medium, and trends will have to be monitored with
later arriving model and observational datasets.

Outlook...

Tuesday Night: Low Operational Impact. Breezy. Slight Chance of SHSN.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: Moderate Operational Impact. Chance of SHRA...RA.
Friday Night: Moderate Operational Impact. Chance of SHRA...RA.
Saturday: No Operational Impact. NO SIG WX.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Lake Effect Snow Warning until midnight EST Tuesday night for
     NYZ032-033.
     Winter Weather Advisory from 7 AM Tuesday to 7 AM EST
     Wednesday for NYZ038.
MA...None.
VT...None.

&&

$$

UPDATE...
SYNOPSIS...32/Wasula
NEAR TERM...Wasula
SHORT TERM...Wasula
LONG TERM...Wasula
AVIATION...32



Area Forecast Discussion

National Weather Service Twin Cities/Chanhassen MN

 1000 PM CST Mon Nov 27 2023

.KEY MESSAGES...
- Tonight, the coldest night of the year so far, with lows in
  the single digits at many locations.

- Transition day Tuesday, with a wide range in temperatures
  from west to east. Warming back above normal for Wednesday.

&&

.DISCUSSION...
Issued at 204 PM CST Mon Nov 27 2023

The Winter feel remains in place across Minnesota and western
Wisconsin, as the ongoing cold air advection regime continues to
usher in the coldest air of the season to date. Air temperatures in
the teens have felt more like the single digits, to even a few
degrees below zero thanks to breezy northwest winds. Afternoon high
temperatures are on track to top out in the low 20s at best for most
locations. Occasional flurries have been noted on observations
across Minnesota throughout the day. RAP forecast soundings are
not particularly impressive when it comes to additional flurry
potential, though the combination of vorticity advection aloft
and a shallow cloud layer near the DGZ may keep some flurries
around the area into the evening. No accumulation is expected.
Another very cold night is ahead, with lows forecast to dip into
the single digits, along with sub-zero wind chills outside of
the Twin Cities metro urban heat island.

While folks may not have been "thankful" for the cold blast
over the past few days, a change in the temperature trend is set
to arrive over the coming days. Tuesday will serve as a bit of
a transition day, beginning with the departure of the upper-
trough to the east, followed by the arrival of a surface warm
front from the Dakotas. The west to east motion and north to
south orientation of the front will result in a 10-15 degree
high temperature gradient between western Minnesota and western
Wisconsin Tuesday afternoon. Locations to the west of I-35 and
south of I-94 are forecast to make a run into the mid 30s,
perhaps even the low 40s along the Buffalo Ridge. Sub-freezing
highs, generally in the mid 20s, can be expected east of I-35
and north of I-94. A fast moving clipper will slide through
northern Minnesota Tuesday, though expectations are that the
local forecast will remain dry.

Much warmer air can be expected area-wide into Wednesday, as the
front shifts further east and mid-level warm air advection
increases. Temperatures will range between the upper 30s in
western Wisconsin to the low to mid 40s west of I-35 in
southern Minnesota. High temperatures will settle back to near
average in the 30s for Thursday and Friday thanks to the return
of northwest flow aloft. High pressure will keep things dry
through the end of the work week, which is great news for those
who still need to do some outdoor decorating!

Uncertainty in the forecast arrives this weekend, as the global
models bring a deep trough over western CONUS. While a myriad of
solutions regarding a potential storm system do exist, there is a
growing signal towards the return of wet, and potential wintry
weather across the ensemble suite. Latest NBM carries scattered PoPs
in the Sunday timeframe, which seems reasonable at this forecast
distance.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 958 PM CST Mon Nov 27 2023
VFR conditions throughout. Low clouds will continue to clear
overnight. Winds will become more south/southwest. Some mid-high
clouds are possible at times.

KMSP...
VFR conditions throughout with west/northwest winds becoming
more south/southwest for Tuesday.

/OUTLOOK FOR KMSP/
Wed...VFR. Wind W 10 kts.
Thu...VFR. Wind NW 10-15 kts.
Fri...VFR. Wind W 5-10 kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.

&&

$$

DISCUSSION...Strus
AVIATION...JRB