pa discuss
Office: CTP
FXUS61 KCTP 021118
AFDCTP
Area Forecast Discussion
National Weather Service State College PA
618 AM EST Tue Dec 2 2025
.SYNOPSIS...
* The first widespread snowfall of the season is underway. Will
be over by late morning in west and in the early aftn east.
* Arctic cold front will deliver snow showers/squalls and much
below normal temperatures Thursday and Friday
* Reinforcing cold blast will ensure the first part of December
will be colder than the historical average with the potential
for another storm system this weekend or early next week
&&
.NEAR TERM /THROUGH TONIGHT/...
Inverted trough will close off today as fast southwesterly flow
aloft keeps things moving. Current 1025mb high over New England
is not going to put up much of a struggle. Sfc low tracks over
or just off the DelMarVA peninsula and then off the NJ coast.
This is a favorable storm track for snow over PA. Nrly wind will
keep cold air in place for much of the time. But, with the high
retreating and the short time of the best moisture plume and
lift over the CWA, the potential for deep snow (6+") is not
strong. The highest potential for 6+" snow amounts is generally
confined to the higher elevations of the Poconos. Many models
make the heaviest snow accums along an axis from AOO-RVL-SEG-
AVP. The most recent NAM and GFS both hint that the axis may be
a short distance (20-40sm) southward. They also keep the srn
part of Lanc Co warm enough to be plain rain for all but the
beginning 1-3hrs. Still, the rates could near 1"/hr in spots. No
real deviations made from going forecast in most if not all
respects due to high continuity. WPC guidance is highly similar,
leading to even stronger confidence. BFD has already been down
below 1sm in SN, but just to the south at OYM and DUJ, the dry
low levels are holding out (for the moment) - keeping the snow
from reaching the ground there. Best lift and hope for
mesoscale banding and 1+"/hr rates still looks like it'll be
between 11Z-16Z. Thought about pulling the advy from Lancaster
Co, but the advy can still be valid if they can squeeze out 2"
and/or get any freezing rain. This is not a favorable
situation/setup for freezing rain in the first place and if it
does occur, it will have snowed a little before hand. That would
make it easier to plow/shovel away - or even notice it at all.
We will keep all headlines in place with timing the same, too.
By 11 AM, the steady snow will be out of the Alleghenies and
Laurels, and by 2 PM it should be done in the east. Upslope flow
does bring in lake moisture to the favored west-facing slopes of
the Laurels for the afternoon and first half of the night,
though accums should be <1".
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
Upper trough axis is through the area around 03Z. 8H temps do
drop to around -10C in the N and even get close to -5C in the
SE. The clouds and --SHSN lingering in the west should go away
quickly on Wed AM. High pressure does pass to our S on Wed,
allowing the flow to come back out of the SW. Layered clouds
build in from the NW again. A true arctic front will cross LE by
sunrise Thurs. This should kick up numerous SHSN and perhaps
some squalls along the front, too. Time of day for frontal
passage is not the best for squalls, as the instability will be
limited to what warmth can be mustered as the air over the lakes
is brought over PA. The moisture is also limited to only what
the lakes can yield. We'll only manage about 10-15F diurnal rise
on Wed, and the SW flow Wed night ahead of the cold front will
keep mins generally 20-25F (again only a 10-15F drop).
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
Thursday will be the frontal passage - either very early AM in
the NW and late AM or mid-day in the SE. The moisture rapidly
disappears as the front goes into the Central Mtns. As mentioned
above, the time of frontal passage is not that favorable for
squalls due to lack of instability/higher stability normally at
that time of day. But, the air airmass is much colder behind the
front. Knock 3-5F off the maxes from Wed to Thurs.
Friday continues to look quite cold, with lows in the single
digits and teens while highs only make it into the 20s to low
30s. Otherwise, temperatures will be fairly consistent for the
upcoming week and weekend, with highs in the 30s and lows in the
teens and 20s.
The threat of winter weather for late week/early weekend seems
to have decreased with the most recent cycle of guidance, but it
has not disappeared. EC most willing to generate snowfall for
our SErn counties as the low passes to our south on it's progs.
GFS keeps the wave moving and does not allow it to move far
enough north to put down any snow over any of PA. Regardless, a
prolonged stretch of colder than normal temperatures and an
active storm track looks to continue into next week.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Widespread IFR flying conditions in light to moderate falling
snow will continue across the airspace through about mid day.
Forecast timing on track. Snow will taper to VCSH during the
afternoon. Confidence in -RA mixing in with the -SN would be
highest (~80%) at KLNS. The melting line should stay south of
KMDT but have a confidence of about 40% that some -RA could
briefly mix in there before the precipitation ends.
As the storm system moves east of the area Tuesday afternoon,
expect northwest winds to increase to 10-15KTS. This may cause
some nominal restrictions in visibility in BLSN but confidence
is too low to warrant wording that far out in the forecast.
Outlook...
Wed-Sat...Trending drier, lingering snow across NW PA. Gusty
winds return Thu aftn.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 1 PM EST this afternoon for
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-
049>053-056>059-063>066.
&&
$$
SYNOPSIS...Dangelo/NPB
NEAR TERM...Dangelo/NPB
SHORT TERM...Dangelo/NPB
LONG TERM...Steinbugl/Banghoff/Colbert
AVIATION...Gartner/Tyburski
Office: PHI
FXUS61 KPHI 021512
AFDPHI
Area Forecast Discussion
National Weather Service Mount Holly NJ
1012 AM EST Tue Dec 2 2025
.SYNOPSIS...
Low pressure tracks northeast towards our area Tuesday into
Tuesday night, bringing widespread precipitation. High pressure
and below normal temperatures return for the middle of the
week. Another cold front will track through the region Thursday
night, with high pressure building back in thereafter. Another
system may impact the region Friday night into the weekend,
before high pressure builds back in for early next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 10:15AM, the rain/snow line is moving north and continues
to progress NW of the I-95 corridor. There has been a slower
progression of this transition zone this morning as the colder
air has held on longer. This has led to more mixed
precipitation including freezing rain. Due to radar data,
observation trends, and reports, the Winter Weather Advisory
running from western Montgomery county in PA to Somerset county
in NJ was extended to 12PM today. Chester county was allowed to
expire as temperature trends are now above freezing and winter
precipitation looks to have ended as the transition to rain has
occurred. All other Winter Weather Advisories remain unchanged
as these areas continue to see winter precipitation.
The previous discussion below remains on track:
The low pressure system remains the main story for the near term
period as it continues to approach the area this morning and
then off the coast by this afternoon, which will continue to bring
widespread precipitation to the region, including the first
accumulating snowfall to portions of the area. This low will
make its closest approach to the area as it passes offshore this
afternoon, and begins departing to the northeast tonight.
In terms of the details with this system, the forecast largely
remains on track. The precipitation remains widespread across
the area with the highest PoPs (90-100%) remaining during the
daytime hours today.
Observations indicate that temperatures continue to increase
with subtle warm air advection as the system approaches.
Continuing through the day today, the onshore flow and warm
marine influence with the surface low drawing near will impact
the temperature profiles. For perspective on this, high
temperatures today will be near or a couple degrees above
freezing in the Poconos, mid 30s to near 40 degrees northwest of
the fall line, low 40s along the I-95 corridor, and in the mid
40s to low 50s in Delmarva and along the coastal areas.
Through the morning hours, the rain/snow line will inch closer
to I-78. During the afternoon, the rain/snow line has the
potential to reach into the Poconos and parts of northwest NJ.
With the aforementioned highs being near/just above freezing in
the Poconos, there is even the potential for mixing in the
higher elevations of these areas above 1,500 feet.
Regarding more details about the precipitation accumulation, QPF has
remained about the same with the latest updates. Totals continue to
range from 0.50-1.00" with localized amounts to 1.25" with the
greatest across the coastal plain and least farther inland north of
I-78.
As for snowfall accumulation, the forecast has remained about the
same with this update. The probability for plowable snow (2" or
more) remains high (60-90%) in the Poconos and areas along and north
of I-78. As you head well south and east of I-78, the potential for
plowable snow quickly decreases to near 0% for the I-95 corridor.
Our latest forecast includes snowfall amounts of a few tenths of an
inch for the very NW portion of the I-95 corridor, up to an inch for
areas just northwest of there, and in the 1-3" range for the I-78
corridor and NW NJ. Higher elevations (especially 1,500 feet and
higher) in NW NJ and across the Pocono Plateau have potential for
snowfall in the 3-6" range.
Outside of potentially the Poconos and perhaps the higher elevations
in NW NJ, the snow that falls will then be melting through the day
with the change to all rain and warm air moving further inland.
During the transition period from snow to rain, some sleet is
possible briefly. Due to the stronger signal of warmer air advecting
in, the transition zone from snow to rain may not be as clean. There
is now the potential for a light accumulation of ice from freezing
rain in the transition zone northwest of the I-95 corridor. The ice
accumulation looks to be a light glaze.
The Winter Weather Advisory for the southern Poconos and Sussex
County NJ is unchanged, remaining in place through the day today, as
snow and/or mixed precipitation will continue in this area until the
system departs this evening.
The Winter Weather Advisory for the next tier of counties
southeastward in northern NJ and the I-78 corridor and down into the
far northwestern reaches of the Philly metro, has been expanded to
include Somerset County in New Jersey. These are the areas most
likely to experience a troublesome Tuesday morning commute, with
snowfall up to the 1-3" range as well as light glaze of ice from
freezing rain.
For the remainder of the region that will see all rain or a change
to rain early on will have a good soaking all-day type of rain. A
few precipitation and/or snowfall records could be challenged. See
the Climate section below for more details on the records.
Once the low departs late this evening, a high pressure system will
build in from the southwest. This will lead to drier conditions
through tonight. Lows tonight are in the 20s for most, which may
lead to some black ice issues where any slushy snow melt refreezes
on roadways (especially north of I-78).
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
By Wednesday morning, the axis of the H5 trough that will lead to
Tuesday's widespread precipitation will be in the Gulf of Maine
vicinity, rapidly lifting northeast away from the area. A subtle
upper-level ridge axis will shift eastward across the area through
the day Wednesday. Wednesday night into Thursday, enhanced
southwesterly flow aloft will begin to overspread the area as a
trough digs southeastward over portions of Ontario and eventually
Quebec. The trough axis will pass to the north/glance the region
Thursday. Subtle height rises will follow with flow aloft becoming
zonal Thursday night. At the surface, high pressure will build in
from the west on Wednesday. A surface low will pass well to the
north of the area on Thursday with a strong trailing cold front
moving through by Thursday evening.
Wednesday should be a partly to mostly clear day. Highs will range
from the mid 30s across eastern PA and northern NJ to the low 40s
across southern NJ and the Delmarva. Wednesday night will feature
increasing clouds from northwest to southeast as the cold front
begins to approach the region. Lows will be in the low-mid 20s
across most of eastern PA and NJ, with upper 20s to near 30 for the
coastal plain, urban corridor, and Delmarva.
Thursday will be partly to mostly cloudy ahead of the front. While
not explicitly mentioned in the forecast at this time, a couple of
snow showers could occur with the frontal passage across the
Poconos. If this were to occur, accumulation amounts would be
light. Otherwise, it looks to remain dry. Will defer to future
shifts on potential inclusion of PoPs for this region. Highs
will generally be in the 30s northwest of I-95 and 40s
southeast. Skies should clear behind the front, but breezy
northwest winds will ensue, so it will be quite chilly.
With the cold post-frontal airmass in place, decreasing winds, and
partly to mostly clear skies, the stage will be set for a very cold
Thursday night. Lows are expected to be in the single digits across
the Poconos and into far northwestern NJ, the teens across the
remainder of eastern PA and NJ, and the low 20s across the
Delmarva.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
Friday looks to start with high pressure centered over our area
under zonal flow aloft. Deterministic guidance still shows the
potential for a weak impulse aloft to track through the region
Friday night into Saturday. The surface high will shift
eastward and off the coast Friday night into Saturday. Ensemble
guidance still suggests the possibility of surface cyclone
formation across the Carolinas, though consensus remains that it
will be a weaker storm that will stay south of us, with only a
glancing blow. We continue to have a chance (30-50%) PoPs
across most of the area for Friday night, with the greatest
chances across southern DE and far southeastern NJ. These
ultimately may continue to come down, but trends will be
monitored in the coming days as this potential storm system gets
closer in time. The airmass in place will be cold enough that
any precipitation that does fall across the area with this
system would have the potential to be of the wintry variety.
Regardless of precipitation chances for Friday night into Saturday,
the pattern favors well below average temperatures. In fact,
temperatures may remain below freezing on Friday for most of eastern
PA and northern NJ, and only reach the mid 30s across the Delmarva
and into southern NJ. Saturday and Sunday look to remain below
average, though slightly warmer than Friday. Another cold front
could bring at least low precipitation chances and a renewed shot of
cold air Sunday night into Monday.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.
Today...IFR/LIFR conditions develop between 11z-15z. High
confidence in all rain at KACY/KMIV. The trend as of this
morning has been warmer and slower with precipitation moving in.
This will result in pretty much all rain for KILG/KPHL and have
taken snow out of the TAF for now. Cannot rule out a few
flakes/mix at onset, but would expect a quick flip to rain once
precipitation begins. For KPNE/KTTN, expecting a longer period
of snow and/or mix, but a flip to all rain should occur by 14z.
A period of all snow expected at KRDG/KABE till about 14z before
mixing occurs and eventual flip to all rain after 18z. High
confidence in at least IFR through the morning with the
potential (25-35%) in prevailing LIFR. Moderate confidence in
timing of precipitation type changes. Winds will be out of the
east/northeast around 5-10 kt, expecting to shift to
north/northwest between 19z-22z. Moderate confidence in timing
of wind shifts.
Tonight...Conditions gradually improving with rain coming to and end
though MVFR/IFR expected to start, with VFR anticipated to return
between 03-06Z. Northwest winds around 10 knots with gusts up to 20
knots possible. Moderate confidence.
Outlook...
Wednesday through Wednesday Night...VFR. No significant weather.
Thursday...VFR. Gusts near 20 kt expected out of the
west/northwest
Thursday Night through Friday...VFR. No significant weather.
Friday Night through Saturday...Restrictions possible (40-60%)
with rain and snow showers moving through.
&&
.MARINE...
No marine hazards are anticipated through early this morning with
seas 2-3 feet and winds out of the east to then southeast gusting to
10-20 knots.
Winds and seas will then increase later this morning. Winds will
gust to 25-30 knots and flip to be out of the north to northwest by
this evening. Occasional gusts to 35 knots are possible on the ocean
zones tonight. Seas will reach 5-7 feet tonight as well. As a
result, a Small Craft Advisory is in effect beginning at 10 AM today
for the Atlantic Ocean coastal waters and at 3 PM for the Delaware
Bay. The SCA will continue through tonight for all coastal
waters.
Outlook...
Wednesday...SCA conditions linger into the first part of the
day. While winds are expected to have subsided, seas of 4-6 feet
are expected in the morning, decreasing to 2-4 feet through the
day.
Wednesday night...No marine headlines are anticipated with winds
below 25 kt and seas below 5 feet.
Thursday through Thursday night...SCA conditions are possible with
northwest winds 15-25 kt and seas 3-5 feet.
Friday through Saturday...No marine headlines are anticipated with
winds below 25 kt and seas below 5 feet.
&&
.CLIMATE...
Widespread moderate to heavy precipitation is expected on
Tuesday, December 2nd. A few daily precipitation and/or snowfall
records could be challenged. Records for our climate sites are
listed below:
Record Precipitation (Rainfall)
December 2
Site Record/Year
Allentown (ABE) 0.86"/1934
AC Airport (ACY) 1.03"/1996
AC Marina (55N) 1.18"/1929
Georgetown (GED) 1.11"/1974
Mount Pocono (MPO) 3.56"/1996
Philadelphia (PHL) 1.48"/1986
Reading (RDG) 1.29"/1981
Trenton (TTN) 2.13"/1986
Wilmington (ILG) 1.27"/1991
Record Snowfall
December 2
Site Record/Year
Allentown (ABE) 3.6"/1952
AC Airport (ACY) T/2019*
Philadelphia (PHL) 2.0"/1903
Reading (RDG) 6.0"/1929
Trenton (TTN) 3.0"/1903
Wilmington (ILG) 1.0"/1952
*Multiple years with a Trace.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory until 1 PM EST this afternoon for
PAZ060>062.
Winter Weather Advisory until noon EST today for PAZ103-105.
Winter Weather Advisory until 6 PM EST this evening for PAZ054-
055.
NJ...Winter Weather Advisory until 7 PM EST this evening for NJZ001.
Winter Weather Advisory until 1 PM EST this afternoon for
NJZ007-008.
Winter Weather Advisory until noon EST today for NJZ009-010.
DE...None.
MD...None.
MARINE...Small Craft Advisory from 3 PM this afternoon to 6 AM EST
Wednesday for ANZ430-431.
Small Craft Advisory until 1 PM EST Wednesday for ANZ450>455.
&&
$$
SYNOPSIS...MJL
NEAR TERM...AKL/Guzzo
SHORT TERM...Cooper/MJL
LONG TERM...Cooper/MJL
AVIATION...AKL/MJL
MARINE...AKL/MJL
CLIMATE...WFO PHI
Office: PBZ
FXUS61 KPBZ 021159
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
659 AM EST Tue Dec 2 2025
.SYNOPSIS...
Widespread precipitation expected this morning, with impactful
snow accumulation for much of the region. After a brief break
Tuesday night into Wednesday, an active weather pattern and
below-normal temperatures continue into next weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
KEY MESSAGES:
- A Winter Weather Advisory remains in effect for the entire
area until 1 PM
- Widespread snowfall accumulations of 2-5 inches, especially
north of I-70. Heaviest snowfall rates occur between 4 AM and
8 AM, impacting the morning commute
- Mixed precipitation in the Mon Valley and the ridges of SW PA
and northern WV, including a chance for light ice accumulation
due to periods of freezing rain
- Precipitation ends from west to east by late morning or early
afternoon
---------------------------------------------------------------
Early Morning Update:
Widespread light to occasionally moderate snowfall is ongoing
across much of the area as of 630AM EST, with a wintry mix of
snow/sleet/freezing rain in the Mon Valley as warm air aloft
attempts to nose its way slowly northward. Snow accumulations
are on track with the forecast, with most early morning report
indicating between 1-3 inches having fallen across the region
thus far (locally up to 4 inches in spots). Numerical guidance
appears to have a solid handle on this event to this point and
continues to suggest accumulating snow ends from west to east
during mid to late morning hours, roughly the 8-9AM timeframe in
eastern OH, 9-10 AM in the lowlands of western PA and northern
WV, and lingering a little longer to around Noon in the ridges.
An additional 1-3 inches of accumulation will be possible
through that time.
Even after accumulating snow ends, a dense low cloud deck is
forecast to linger throughout the day so there won't be much (or
any) sunshine to help melt snow and ice. Still, with high
temperatures climbing slightly above freezing, some melting may
occur on untreated roads this afternoon, but low temperatures in
the 20s tonight will pose a threat for refreezing and icy
conditions into Wednesday morning.
Previous Discussion:
Little change was needed to the forecast through today, as the
sequence of events is playing out largely as expected. An
upper trough, currently crossing the western Great Lakes, will
swing into the Middle Ohio Valley this morning and into the
Appalachians by this evening. Models continue to agree on the
track of the associated surface low, bringing it up the Atlantic
Coast today and to just off of southern New England by 00Z.
Precipitation is in the process of overspreading the region,
having begun here in Moon at about 0715Z.
Warm advection ahead of the system has led to rising
temperatures south and east of Pittsburgh, with LBE, MGW, and
VVS all rising into the mid 30s as of 2 AM. HRRR soundings here are
suggesting a weak warm layer aloft, or even near isothermal
profiles around 0C, suggesting perhaps some sleet or freezing
rain at onset, before wet-bulbing changes much of this over to
snow. Lower snow-to-liquid ratios (6:1 to 10:1) are expected as
compared to areas to the northwest. However, a stronger and
more persistent warm layer aloft remains more likely in the area
of the Laurels and especially the West Virginia ridges, where
freezing rain is more of a threat. Only a light glaze is
expected in most cases, but eastern Tucker County could see a
more meaningful ice accretion of a tenth of an inch or so this
morning. Some plain rain should even mix in by the tail end of
this event.
Otherwise, in areas west of I-79 and north of I-70, all snow is
forecast for the event, with SLRs generally in the 10:1 to 14:1
range. We are already seeing visibilities of a mile or less at
a few locations. The heaviest snow rates are still pictured to
be in the 4 AM to 8 AM window, creating widespread impacts
during the morning commute. The HREF continues to suggest that
instantaneous snow rates of 1 inch per hour remain possible in
banded precipitation in the overall shield, supported by 700mb
frontogenesis and jet-aided ascent. Storm total snowfall of at
least 3 inches has a 50 to 80 percent probability of occurrence
in the all-snow region, with lower probabilities in the mixed-
precipitation region to the south and east. Best probabilities
of 4 to perhaps 5 inches in spots, at around 50 percent, lie
northeast of Pittsburgh. Given all of this, sufficient impacts
to the morning commute are expected to justify the continued
existence of the CWA-wide Winter Weather Advisory, even if
accumulation criteria are not technically met in some locations
to the southeast of Pittsburgh.
Precipitation should end fairly rapidly from west to east
during the late morning and early afternoon as the low pulls
into the Atlantic and as moisture depth decreases with the
passage of the shortwave trough axis. Some snow showers may
linger near and north of I-80 as well as in the ridges with a
brief push of NW flow, but additional accumulation should not be
as impactful, remaining under an inch. Trends will continue to
be monitored to see if a localized extension of the Winter
Weather Advisory could be needed, particularly in the ridges.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
KEY MESSAGES:
- Mostly dry and cold Tuesday night and Wednesday
- A front Wednesday night into Thursday provides a reinforcing
cold shot and some minor snow accumulation
----------------------------------------------------------------
Isolated snow showers may linger north of I-80 and along the
ridges in northwest flow, but slowly backing low-level wind and
falling inversion heights should help to largely shut off this
activity by midnight, with little additional accumulation.
Surface high pressure crosses the Middle Ohio Valley and the
Central Appalachians later Tuesday night and Wednesday, and
extends ridging up into the forecast area. This should provide
dry weather and continued chilly temperatures. Maximum values on
Wednesday will continue to run some 10 to 12 degrees below
climatology.
The next cold front, extending from low pressure over Hudson
Bay, is forecast to cross the region late Wednesday night and
Thursday morning. The associated shortwave trough is expected to
remain mostly over the northern Great Lakes, keeping much of the
synoptic support to our north. Still, the boundary will provide
a reinforcing shot of cold air as 850mb temperatures drop into
the -10C to -15C range by Thursday afternoon. Given the system's
northern origins, moisture remains limited overall. A shot of
light snow is forecast, with quite minor accumulation. Areas
south of I-80 have a 30 percent or less chance of exceeding a
half inch. Portions of Mercer and Venango that may be more
favored for lake-enhanced activity could see an inch or so by
the time the snow cuts off Thursday afternoon. Here, model
soundings hint at some modest instability and reasonably steep
lapse rates into the DGZ that could support briefly stouter snow
showers during peak heating. However, better potential for such
activity, including snow squalls, lies to the north with deeper
moisture and instability.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
KEY MESSAGES:
- Dry and cold Thursday night and Friday
- Below average temperatures and continued wintry precipitation
chances into early next week
-------------------------------------------------------------------
Dry weather is forecast for Thursday night and Friday as high
pressure crosses in quasi-zonal flow. A mostly clear sky and light
wind may aid radiational cooling on what looks to be the coldest
night of the season thus far. Many locations away from urban areas
and major river valleys have a 50 percent or greater chance of low
temperatures colder than 10 degrees according to the NBM. Below-
freezing high temperatures are expected Friday for many areas north
of I-70.
For Saturday, ensembles generally drag a weak 500mb shortwave across
the Upper Ohio Valley with a Great Lakes surface low. There are some
questions regarding precipitation type, but amounts appear to be
light overall. Some modest temperature recovery may occur, into the
mid to perhaps upper 30s in spots. Thereafter, additional shortwave
activity may continue to keep a trough carved out across the
northeast CONUS into early next week, promising continued below-
normal temperatures and further chances of wintry precipitation.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
KEY MESSAGES:
- Snow arrives after 06z bringing widespread IFR and lower
restrictions areawide
- Period of worst conditions likely between 08z-14z
- Southeasterly wind veers northwesterly by Tuesday afternoon
-------------------------------------------------------------------
Widespread snow (and wintry mix in the Mon Valley) is ongoing to
start the TAF period, with a mix of IFR/LIFR ceilings and
visibilities at all area terminals. These conditions will
continue until accumulating snow ends from west to east during
mid and late morning. Latest guidance continues to suggest this
happens roughly in the 13z-14z timeframe at ZZV, 14z-15z at
PIT/AGC, and 16z-18z at LBE/DUJ. Flurries may linger across
western PA through the afternoon, but little to no accumulation
nor any notable impact to visibilities are expected. Ceilings
are expected to gradually rise to MVFR through the afternoon,
but may lower again (except for ZZV) this evening and overnight
tonight.
Light and variable winds this morning become northwesterly and
increase slightly (occasional gusts to around 15kts) by this
afternoon following a cold frontal passage.
Outlook...
Gradual ceiling improvement is expected on Wednesday with
eventual return to VFR Wednesday afternoon. Additional light
snow chances and restrictions are possible again Wednesday night
into Thursday morning (favoring locations north of PIT) and
during the day Friday (favoring locations south of PIT).
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory until 1 PM EST this afternoon for
PAZ007>009-013>016-020>022-029-031-073>078.
OH...Winter Weather Advisory until 1 PM EST this afternoon for
OHZ039>041-048>050-057>059-068-069.
WV...Winter Weather Advisory until 1 PM EST this afternoon for
WVZ001>004-012-021-509>514.
&&
$$
SYNOPSIS...CL
NEAR TERM...CL
SHORT TERM...CL
LONG TERM...CL
AVIATION...Cermak
