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Office: CTP

FXUS61 KCTP 162005
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
405 PM EDT Tue Oct 16 2018

.SYNOPSIS...
A cold front will move in Wednesday morning and reinforce the
cold with frequent rain showers across the northwest mountains
during the day Wednesday and scattered afternoon and night-time
showers across the Laurel Highlands.

The rain showers will change to snow showers Wednesday night
across the northwest mountains with the first ground covering
likely.

The breezy southwest wind today and tonight will get stronger
on Wednesday behind the cold front with gusts into 35 to 40 mph
range at times, especially over the Laurel Highlands and South-
Central Mountains.

Occasional rain and snow showers will occur across the Northwest
Mountains Thursday, while mainly dry and much cooler than normal
weather persists elsewhere Thursday into Friday as the center
of high pressure drifts by just to the south of PA

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Axis of a potent, 150 kt westerly 300 mb jet was located right
over the I-80 corridor in PA this midday hour, with a shield of
cirrus and cirrostratus streaming along its southern periphery.

Area of thick strato cu present earlier this morning across the
north has dissolved and lifted north into the Niagara region of
New York State as the mean LLVL flow backed to the WSW.

Look for little change in current sky cover across the state
late this afternoon through at least the first half of tonight.

Temps will warm by another 1-3 degrees through 20Z with highs
ranging from the U40s across the NW Mtns to the U50s in the SE.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
Another cold front with even chillier air behind it will arrive
on Wed AM across the NW mtns. The timing of the arrival of
precip and colder air may allow for a few flakes of snow. But,
most of the precip should be in the form of occasional light to
moderate rain showers, as the mixed air parcels being advected
well-inland off Lake Erie will be very warm and likely super-
cooled when suspended in the clouds with temps mainly in the -3C
too -6C range.

The showers should only make it about half-way through the CWA,
getting eaten up by the downslope off the Allegheny Front within
the rather strong anticyclonic llvl flow.

Max temps Wed will range from only near 40F over the higher
terrain near KBFD, to near 60F in the far SE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
A shot of cold air via brisk NW flow will top the Great Lakes
and produce lake effect rain/snow showers Wednesday night into
Thursday. A light accumulation (<1 inch) is expected in the
higher elevations of the snowbelt region downwind of Lake Erie.
This will be the first snow accumulation of the 2018-19 winter
season. Lingering lake effect snow/rain showers should end by
Thursday afternoon.

Frost/freeze conditions are likely Thursday night into Friday
morning. Frost/freeze headlines are probable for areas to the
east of the Allegheny Front where the "extended" growing
season remains active.

Occasional rain showers are likely early Saturday in advance of
a sharpening cold front poised to sweep across the Appalachians
Saturday evening. A more pronounced shot of cold air will follow
in the wake of the frontal passage, likely supporting a greater
coverage of snow showers/flurries across the Alleghenies Saturday
night through Sunday. Additional snow accumulation is probable
in the favored lake effect zones and upslope/higher terrain.
Wind chills in the low 30s to mid 40s on Sunday will make it
feel more like early December than late October. Conditions
should improve into Monday as high pressure migrates eastward
from the Mid MS Valley.

Below average temperatures are strongly favored to continue
next week and likely last through the end of the month.

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
Expect widespread VFR at all airfields through much of tonight
in West to SW flow ahead of a cold front slicing through the
Upper Great Lakes at this time.

MVFR, then IFR Stratocu deck will spread across the NW mtns,
then into the central zones very late tonight through Wednesday
morning along and in the wake of the cold front.

LLWS placed in all tafs tonight through the time of the cold
frontal passage mid-late Thursday morning in most places. In the
wake of the cold front, westerly winds will gust between
30-35kts Wednesday with widespread mechanical mixing causing
turbulence and cross-wind affects impacting takeoff and FAP.

.Outlook...

Wed - Thursday morning...Gusty NW winds. Wed PM snow
showers/vis reductions possible NW Mtns. VFR to tempo MVFR
strato cu Wed afternoon into Thursday in the KAOO to KUNV and
KIPT corridor.

Thu afternoon-Fri...No sig wx expected.

Sat and Sunday...AM low cigs possible W Mtns Sat. Elsewhere
Scattered showers and areas of mainly MVFR CIGS as a cold front
pushes SE across the PA airfields. Then...SHSNRA/cig reductions
possible NW Mtns after dark Sat evening and through much
Sunday.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...Lambert
NEAR TERM...Lambert
SHORT TERM...Lambert
LONG TERM...Steinbugl
AVIATION...Lambert



Office: PHI FXUS61 KPHI 161942 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 342 PM EDT Tue Oct 16 2018 .SYNOPSIS... High pressure will lose its influence over our weather tonight. A cold front approaching from the northwest is forecast to arrive on Wednesday afternoon. High pressure is expected to build across our region from the west on Thursday and Friday. Another cold front is anticipated on Saturday afternoon, followed by high pressure for Sunday and Monday. The next in the series of cold fronts is expected on Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Dry weather conditions are expected to continue into this evening with just some cirrus overhead associated with an upper level jet. An impulse traveling in the mid level flow was bringing some rain to the Tennessee River Valley and vicinity this afternoon. The feature is expected to progress east northeastward, passing off the Middle Atlantic coast late tonight. The northern edge of the area of rain is anticipated to brush across the middle Delmarva and far southern New Jersey overnight. The remainder of our forecast area should stay precipitation-free. Low temperatures are expected to range from the upper 30s in parts of the Poconos, the Lehigh Valley and northern New Jersey to around 50 in southern Delaware and in the adjacent counties of eastern Maryland. The wind should be light and variable. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... A mid level trough is forecast to move from the Great Lakes on Wednesday morning to the northeastern states on Wednesday afternoon and evening. A surface cold front associated with the mid level feature is expected to pass through our region on Wednesday afternoon. The system will lack any significant moisture, so clouds will be limited and we will mention only a slight chance of showers from the Poconos into northern New Jersey. A gusty west wind is anticipated to develop on Wednesday with sustained speeds increasing to 15 to 20 MPH with gusts of 25 to 30 MPH. High temperatures will likely be in the 50s up north and in the lower and middle 60s in the rest of our forecast area. The sky is expected to be mostly clear on Wednesday night. Temperatures should drop into the 30s and lower 40s. The wind is forecast to be from the northwest around 10 MPH, precluding the development of frost in areas that fall below the upper 30s. Nevertheless, we could see some sub-freezing temperatures in the elevated terrain of the Pocono and far northern New Jersey. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Thursday and Friday...The main influence through this period will be a surface high slowly building east in combination with a mid and upper level ridge propagating east as well. The combination of these two factors will lead to dry weather, and a warming trend. The warming trend will be especially noticeable Friday into early Saturday as the surface high builds east of our region, leading to low level southwesterly flow. Before the warming trend gets started, we could see a round of frost Thursday night for location northwest of the I-95 corridor. Saturday...Cold front should arrive through the second half of the day. Unlike with the Wednesday front, there should be plenty of moisture advection ahead of this front, thanks in large part to the southwesterly flow ahead of the front. For now have kept the weather type as showers, but depending on the arrival time of the front, especially if it arrives before sunset, we could see some thunderstorms across the region. Sunday through Tuesday...Dry and cool conditions are expected through this period. Frost or even a hard freeze is possible especially Sunday night into Monday morning. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...VFR. Westerly wind 4 to 8 knots this evening, becoming variable 5 knots or less overnight. Wednesday...VFR. West wind increasing around 15 knots with gusts of around 25 knots. Wednesday night...VFR. Northwest wind 6 to 12 knots. Outlook... Thursday through Friday...VFR conditions expected. Light wind becoming southwesterly on Friday around 10 KT. Saturday...Mostly VFR though temporary visibility and ceiling restrictions are possible with showers. Winds starting southwesterly, but an abrupt shift to northwesterly is expected late in the day Saturday. Saturday night and Sunday...VFR conditions expected. Northwest wind 5 to 10 knots Saturday night increasing to 10 to 15 knots on Sunday. && .MARINE... We are anticipating a westerly wind less than 15 knots into this evening. Wind speeds are forecast to increase gradually late tonight with gusts in excess of 25 knots expected to develop on Wednesday morning. As a result, a Small Craft Advisory is in effect for Wednesday on our ocean waters and on Delaware Bay. The trend toward higher wind speeds will continue into Wednesday night, with gale force gusts likely at that time on our ocean waters and on lower Delaware Bay. A Gale Warning Outlook... Thursday...Northwesterly wind gusts of 25 to 30 KT are expected. Thursday night and Friday...No marine headlines are anticipated. Friday night and Saturday...Southwesterly wind gusts around 25 KT are possible with an abrupt shift to northwesterly late in the day Saturday with gusts up to 30 KT possible. Saturday night and Sunday...Northwesterly wind gusts of 25 to 30 KT are expected. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory from 11 AM to 6 PM EDT Wednesday for ANZ431-452>455. Gale Warning from 6 PM Wednesday to 9 AM EDT Thursday for ANZ452>455. Small Craft Advisory from 8 AM to 6 PM EDT Wednesday for ANZ450-451. Gale Warning from 6 PM Wednesday to 6 AM EDT Thursday for ANZ431-450-451. Small Craft Advisory from 11 AM Wednesday to 6 PM EDT Thursday for ANZ430. && $$ Synopsis...Iovino Near Term...Iovino Short Term...Iovino Long Term...Johnson Aviation...Iovino/Johnson Marine...Iovino/Johnson
Office: PBZ FXUS61 KPBZ 162204 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 604 PM EDT Tue Oct 16 2018 .SYNOPSIS... Dry weather is expected until the approach and passage of a Wednesday cold front. Dry weather is expected to return Thursday through early Friday under high pressure. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... A ridge of high pressure should maintain dry weather tonight. An increasing pressure gradient between the high and an approaching cold front from the N should keep winds around 5-10 mph as lows drop to near or just below average. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/... Isolated to scattered showers are expected Wednesday with the approach and passage of an upper trough and its associated sfc cold front. More numerous coverage is expected N of I 80, where the best upper support is progged, and where some lake enhancement is expected. The pressure gradient should further tighten through the day. This, along with mixing, should result in wind gusts of 30-35 mph, with gusts around 40 mph in the higher terrain. Showers should taper off Wednesday night as the upper trough exits. There will be slight chance that snow will mix in with rain showers in our northeastern counties late Wed night. However, a building high pressure to the west could cut off our moisture supply before the ideal time frame for snow to form. Regardless if snow does fall, the ground will too warm for any accumulation to form. With the sfc high pressure pushing through, Thursday will remain dry and mostly sunny. However, high temperatures will be struggling to get to 50 degrees everywhere as cold air from the north continues to seep into our region. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Warmer temperatures return Friday as weak upper shortwave ridging passes over the area. However, the ridge will be short lived as another upper level trough moves over the Great Lakes. Rain chances will increase late Friday and into Saturday morning as a swath of warm air from the south cuts across the Appalachians. Rain chances will taper off throughout Sunday afternoon and evening as another sfc high builds in the lower Midwest. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... With the exception of MGW, FKL, and DUJ, TAFs are expected to be VFR throughout the period. Conditions have gone back and forth between sct/bkn MVFR cigs at MGW this afternoon, and high clouds should be the rule elsewhere. While skies should clear out tonight, low to mid VFR cigs should move south late tonight into Wednesday morning with a cold front. Late Wednesday morning is when ceilings are expected to drop to MVFR at FKL/DUJ, but remain VFR at other ports. As of the 18Z TAF issuance, FKL is the only site which has reported gusts multiple hours. With gusts up to 20 kt in the previous forecast at most locations, have kept gusts at most sites this afternoon, but lowered the gust values. Winds will drop to 5-10 kt overnight, but gusts above 20 kt are anticipated again tomorrow afternoon with the passage of a cold front. Outlook... More widespread restrictions are likely with a Fri night/Sat cold front. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...None. OH...None. PA...None. WV...None. && $$