Area Forecast Discussion Issued by NWS Albany, NY
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FXUS61 KALY 281145
AFDALY
AREA FORECAST DISCUSSION
National Weather Service Albany NY
645 AM EST Sun Feb 28 2021
.SYNOPSIS...
The next system will move across the region later today
through tonight with scattered rain showers and perhaps a wintry mix
across some higher terrain areas. A strong cold front will cross the
area Monday afternoon and evening and advect in a much colder air
mass along with strong winds and scattered snow showers and
squalls. Blustery and cold conditions are expected on Tuesday as
an area of high pressure builds into the region.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 630 AM EST...No major changes to the current forecast.
Main change was to update temperatures based on the latest
trends. Pops may need to be reduced or delayed even further for
this afternoon and evening based on some of the latest model
guidance, but will refer to later updates to make any further
adjustments.
High pressure will depart to our east this morning as the next
system approaches our area from the south and west. This system is
split into two parts. The first part is a wave of low pressure
tracking eastward across the mid-Atlantic. The second part is an
area of low pressure lifting northeastward from the Great Lakes
toward Hudson Bay which lifts a mid-level warm front across the
region this afternoon and evening and then sends a weak cold front
across our region Monday morning.
Today will start out mostly cloudy and dry. Precipitation will begin
to break out during the afternoon and evening hours. The best areas
for some precipitation will be across the mid-Hudson Valley into the
Litchfield Hills (from the mid-Atlantic low) and then across the
Adirondacks (from the Great Lakes low). Activity elsewhere should be
fairly limited with much of the afternoon and evening likely being
dry. Precipitation will be mostly all rain; however, forecast
soundings suggest some light freezing rain/drizzle will be
possible across the higher elevations of the eastern Catskills,
southern Adirondacks and southern Greens for a time with air
temperatures hovering near or just below freezing. Any ice
accumulations will be generally a light glaze. Coverage looks
rather localized so will hold off on a Winter Weather Advisory
for these areas and issue Special Weather Statements for slick
travel, if necessary.
During Sunday night, additional showers are possible in advance
of the front. Air temperatures will remain or rise above
freezing in all locations. Toward daybreak, some cooler air
will begin to reach the southern Adirondacks where some snow
showers may mix in with the rain prior to daybreak.
High temperatures today will range from the mid to upper 30s across
the higher terrain to the lower 40s in the valleys. Lows tonight
will be mainly in the 30s.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
The weak cold front will push to the east early Monday with
showers gradually coming to an end. In its wake, a stronger cold
front will push across the region during the afternoon and
evening. Temperatures will increase slightly in the morning
(especially along and east of the Hudson Valley) before falling
behind the front. Strong low- level lapse rates and weak
instability will develop ahead and just behind the front. As
moisture gets picked up from the Great Lakes, isolated to
scattered snow showers and squalls will be possible Monday
afternoon and evening. Any heavier snow shower or squall could
greatly reduce visibility and produce a quick coating to an inch
or so of snow. As drier air moves in later Monday night, the
snow shower activity will end.
Behind the front, winds will pick up out of the west to northwest
Monday afternoon through Monday night with gusts 35 to 45 mph
possible. Wind headlines may be needed if confidence increases on
this wind potential.
Low temperatures Monday night will bottom out to near or below zero
in the Adirondacks to the mid-teens in the mid-Hudson Valley. Wind
chills early Tuesday morning will be as low as 15 to 25 degrees
below zero across the southern Adirondacks and southern Greens and
around 0 to 15 below elsewhere.
High pressure will gradually move into the region on Tuesday with
sunshine, but it will be quite cold with 850 hPa temperatures
between -15 to -25 C (2 to 3 standard deviations below normal). High
temperatures will only reach the teens across the higher terrain to
the 20s to lower 30s elsewhere (about 10 to 15 degrees below
normal). It will remain windy with wind gusts 35 to 45 mph possible
and will lead to wind chill values only reaching the single digits
and teens for most areas. Wind will gradually lessen during the
afternoon hours as the pressure gradient begins to weaken.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The extended forecast begins with temps returning to above normal
readings for the mid-week. However, a cold front moving through
Thursday will allow temps to trend back below normal into next
weekend as mean mid and upper level trough becomes established over
the Northeast and eastern Canada.
Tue night into Wed...High pressure moves off the Mid Atlantic Coast
Tue night with a split mid and upper level flow pattern impacting
the Northeast. A southern stream cyclone will be ejecting out of
the lower MS River Valley and moving towards the lower Mid Atlantic
States. A northern stream disturbance passes across southeast
Ontario and into northern New England Tue night into Wed. Some
clouds may increase on Wed, but after a cold morning with lows in
the single digits over the southern Dacks, and southern Greens, and
teens over the rest of the region. Highs on Wed with sunshine
mixing with a few clouds will be in the lower to mid 40s with a few
upper 40s in the mid Hudson Valley and NW CT, and 30s over the
higher terrain.
Wed night into Thu...Low pressure passes well south of the region
into the Atlantic. The mid and upper level long wave trough begins
to amplify over the eastern CONUS. A cold front will be approaching
the St Lawrence Valley and the the Great Lakes Region by THU
morning. Some mid and high clouds may increase from the north and
west. Lows will be in the 20s. The cold front dips southward
across the region with very little low-level moisture to work. Some
lake enhanced light snow/rain showers will be possible west of the
Hudson River Valley. Highs on THU are near normal based on the NBM
with upper 30s to lower 40s across the valleys (a few mid 40s near
KPOU) and hills with upper 20s to upper 30s over the mtns.
Thu night into Saturday...Broad cyclonic flow will prevail over NY
and New England with pieces of short-wave energy bringing periods of
clouds and some lake effect snow showers or flurries especially
north and west of the Capital Region towards the western
Adirondacks. Low-level moisture looks sparse, so we kept PoPs slight
chance or lower. H850 temps become -1 to -2 STDEVs colder than
normal on the 00Z GEFS over the forecast area THU night into FRI.
The actual temps may plummet to -20C to -25C. Lows Thu and Fri
night will be in the teens and 20s with some single digits over the
southern Dacks and southern Greens. Highs both days will run below
normal with upper teen to 20s over the mtns, and upper 20s to mid
30s in the lower elevations with brisk northwest winds each day.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
High pressure briefly builds in over NY and New England this
morning. An upper level disturbance and a warm front approaching
from the south and west will increase the clouds and bring some
light rain to the region late this afternoon into tonight.
Patchy mist should dissipate at KPOU between 12Z-14Z and mid
and high clouds will increase during the late morning into the
afternoon. The best forcing for some light rain to move into the
TAF sites will be closer to KPOU/KPSF between 21Z-00Z/MON. The
cigs/vsbys will initially lower to MVFR levels, but reductions
to IFR levels is possible closer to 00Z/MON at those two sites.
Further north clouds thicken and lower and a PROB30 group was
used for KALB/KGFL between 00Z/MON and 06Z/MON for some light
rain or showers with MVFR conditions.
The low-level moisture will increase and expect widespread low
MVFR and IFR conditions to impact the TAF sites prior to
midnight and last until the end of the TAF cycle. Light rain and
drizzle will persist and increase between 06Z-12Z/MON ahead the
sfc wave and warm front.
The winds will be southeast to south at 4-8 kts in the late
morning into the afternoon. The winds will continue to be south
to southeast at 7 kts or less overnight.
The 2 kft AGL winds increase to 35-40 kts in the late
afternoon thru the overnight period and LLWS was added to
KALB/KPOU/KPSF/KGFL 21Z/SUN to 00Z/MON as the sfc winds will be
less than 10 kts. The LLWS will continue until the end of the
TAF cycle.
Outlook...
Monday Night: Moderate Operational Impact. Windy With Gusts To 36 kts. Scattered SHSN...SN.
Tuesday: Moderate Operational Impact. Windy With Gusts To 33 kts. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: Low Operational Impact. NO SIG WX.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: Low Operational Impact. Breezy. NO SIG WX.
&&
.HYDROLOGY...
No major hydrologic issues are foreseen through the upcoming
week.
Some melting and sublimation of the snowpack in the valleys is
expected during the day time over the next several days with the
exception of Tuesday. NERFC forecasts show minor up and down
changes in river flows due to the diurnal freeze/thaw cycle.
River ice is not expected to break up over the next several
days.
The next system will track across the area later today into
early Monday with mainly rain. Total QPF for this system will
range from 0.10 to 0.30 of an inch.
A strong cold front with snow showers is expected to move
through the area Monday afternoon through Monday night. Much
colder air returns Monday night and Tuesday.
Mainly dry weather is then expected for the remainder of the
week.
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...Rathbun
NEAR TERM...Rathbun
SHORT TERM...Rathbun
LONG TERM...Wasula
AVIATION...Wasula
HYDROLOGY...Rathbun