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Office: CTP

FXUS61 KCTP 170621
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
221 AM EDT Wed Aug 17 2022

.SYNOPSIS...
A persistent upper trough will cut off overhead today and slowly
migrate northeast through the rest of the week. Temperatures
will trend gradually warmer to near average values by late week
as the upper low moves up the coast into the Canadian Maritime
provinces.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Lingering light stratiform rain from earlier convection
continues to dissipate over the northern mountains late this
evening. Farther to the south, scattered showers (and isolated
thunder) are finally weakening as they drift westward across the
southern Alleghenies.

Latest short-range guidance suggests that lingering showers
will continue to slowly diminish overnight. There could be some
patchy fog, especially in areas that saw rain on Tuesday and
see partial clearing overnight. Overnight lows will be within a
couple degrees (+/-) of climatology for mid-August.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
With little change in the overall pattern (central PA remains
under the influence of an anomalous 500mb trough), expect
another day of diurnal convection on Wednesday with storm
motions generally from north to south. Daytime highs (low 70s
Laurel Highlands to low 80s eastern valleys) remain near to
slightly below normal.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Cut off upper low will begin to lift out Thursday, but still
enough cool air aloft to support scattered, diurnally-driven PM
convection, mainly over the northern counties. Fair and warmer
conditions return Friday, as upper level ridging briefly builds
over Pa ahead of a deepening upstream trough over the plains
states.

All medium range guidance supports a return to more humid
and unsettled conditions this weekend into early next week, as
a deep southwest flow develops ahead of a slow-moving upper
trough approaching from the midwest. Model consensus tracks a
lead shortwave over our region Saturday, with an associated
weak surface low passing just south of the state. This feature
should produce a chance of showers over central Pa, with even a
period of steadier rain possible over the southeast counties,
closest the surface low track. Scattered PM showers/tsra appear
a good bet Sunday in high pwat air mass with falling heights and
upper level diffluence ahead of upper trough.

Latest ECENS and GEFS indicate the best chance of meaningful,
widespread rain will be in the Monday PM to Tuesday timeframe,
when large scale forcing peaks with passage of upper trough and
plume of anomalous pwats along southwesterly low level jet. An
early guess at possible rainfall early next week based on
ensemble plumes is around a half inch areal average, with
localized amounts of over an inch.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Numerous showers will continue this morning over portions of the
Laurel Highlands and NW Mtns of PA with localized MVFR CIGS and
VSBYS, while the rest of Central PA and the Susq Valley will see
SCT-BKN mid-level, Alto Cu clouds and VFR for the next few
hours.

Localized IFR-LIFR Cigs and Vsbys expected in the 08Z-13Z window
this morning as a result of patchy dense fog - especially in
areas that received significant rainfall Tue afternoon/evening.

Model soundings and ensemble prob charts support a high
confidence of widespread VFR conditions for much of the time
today. However, the mid-upper level low will drift east across
the Commonwealth of PA today, helping to reinvigorate numerous
midday/afternoon showers and scattered TSRA with brief CIG and
VSBY reductions.

Will carry lengthy periods of VCSH compared to designating
several tempo periods for the showers or VCTS.

Somewhat similar conditions expected tonight with localized
dense fog and low Cigs followed by generally VFR for the entire
region Thu and Fri as high pressure builds in with deep NW to
westerly flow drying us out.

Outlook...

Thu...Patchy AM valley fog possible. Isolated PM showers/vis
reductions N Mtns.

Fri...Patchy AM fog possible N Mtns.

Sat...Isolated PM tsra impacts possible W Mtns.

Sun...AM low cigs possible. Scattered PM tsra impacts possible.

&&

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

&&

$$
SYNOPSIS...Steinbugl
NEAR TERM...Evanego
SHORT TERM...Steinbugl/Evanego
LONG TERM...Fitzgerald
AVIATION...Lambert/Fitzgerald



Office: PHI FXUS61 KPHI 170108 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 908 PM EDT Tue Aug 16 2022 .SYNOPSIS... Surface low pressure offshore to the east swings north and northwestward through Thursday before pushing out to the northeast thereafter. Weak high pressure builds in Friday and remains generally over the region through Sunday while a surface low to the south tracks to the northeast. A frontal boundary approaches from the west and could affect the area early next week. && .NEAR TERM /THROUGH WEDNESDAY/... A closed low remains over our area through tonight before it shifts northeastward during Wednesday. Given the positioning of the closed low, our region is sitting beneath an area nearly void of large scale ascent. The forcing for ascent is focused around our forecast area and also closer to an offshore surface low. Any shower activity has been to our west, with a compact cluster of convection well offshore associated with a surface low. While an isolated shower could still occur through early this evening, this may occur only around the Pocono region and therefore slight chance PoPs were retained there. A few showers attempted to form over an area of convergence off the Cape May coast earlier this afternoon but have dissipated with sunset approaching. Kept PoPs in slight chance range offshore a little longer in case anything attempts to form as a cumulus field still exists. The northeast to east wind 10-15 mph with gusts to around 25 mph range (strongest closer to the coast) will diminish as we go into this evening. Temperatures will fall back into the 60s and 50s tonight overall. As we go through Wednesday, the center of the closed low is forecast to be shifting to our northeast. This will place our region more into cyclonic flow aloft with some shortwave energy moving through. Meanwhile, surface low pressure well offshore will be making its way northward toward the New England coast by days end. The bulk of the shortwave energy and lift should become more focused to our north and northeast as the closed low starts to capture the surface low. While a few showers or a low-topped thunderstorm cannot be ruled out primarily during Wednesday afternoon, it looks mostly isolated. Pinpointing where any showers will develop is more challenging in setups like these, however any development may be more tied to terrain areas or differential heating boundaries. Therefore, placed the low mentionable PoPs in some of our western and northwestern areas. The surface flow will be initially out of the northeast Wednesday, although as the surface low tracks closer to coastal New England the winds across our area should back and weaken some. As a result, it maybe a little breezy along the coast to start it should then lessen by late afternoon. The diminishing wind speeds may result in a sea breeze with winds shifting from the east and southeast. Inland, the surface winds may start to turn from the north and northwest during the afternoon. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... A closed low is forecast to lift northeastward into New England and eastern Canada Wednesday night into Friday. Given the positioning of the closed low, our region looks to sit beneath an area nearly void of large scale ascent. It looks like the forcing for ascent is focused around our forecast area and also closer to an offshore surface low. While a few showers or low- topped thunderstorms cannot be ruled out primarily during the peak heating hours, it looks to be rather isolated at best. Any convective development may be more tied to terrain areas or differential heating boundaries. The surface winds weaken Thursday as they becomes east to southerly. Temperatures are forecast to be roughly around average for this time of year with relatively low humidity levels through the period. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... Guidance indicates overall good consistency in the general upper level pattern and its evolution during the long range period. The start of the period sees upper level low pressure in place to our west while upper level high pressure is in place to our north and southeast. This upper level pattern generally holds firm in the following days with not much overall change in upper level features occurring. The ensembles break down the trough to the west and ridge to the southeast some during the Monday and Tuesday timeframe all while the trough to the west and ridge to the north move eastward. At the surface we see weak surface low pressure to our south with weak high pressure generally over our region to start the period. High pressure remains over the region through Sunday though guidance indicates a few isolated showers or storms cannot be ruled out for Saturday and Sunday. Saturday and Sunday see above normal temperatures in the upper 80s and in some locations possibly the low 90s. A frontal boundary looks to approach Monday with widespread showers and thunderstorms possible during the Monday night/Tuesday morning timeframe as the front passes through. Another frontal boundary looks to approach from the west thereafter but confidence in the timing and impacts of this boundary is currently low. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...VFR. East or east-southeast winds around 10 knots diminishing to 5 knots or less to light and variable. Moderate confidence. Wednesday...VFR. An isolated afternoon shower or thunderstorm possible mainly north and west of the I-95 corridor terminals. Light and variable winds becoming northeast around 10 knots, then turning north or northwest during the afternoon at some terminals. A sea breeze could develop and turn the winds east to southeast at ACY. Low confidence on the wind direction details. Outlook... Wednesday night...VFR. Winds becoming light and variable. Moderate confidence. Thursday and Friday...Mainly VFR. Light and variable winds becoming west to southwest around 5 knots Thursday, then south or southeast 5- 10 knots Friday. Moderate confidence. Saturday...Mostly VFR however there is a chance of some showers. Southeast winds 5-10 knots. Low confidence. Sunday...Some times of sub-VFR conditions possible with a chance of some showers. Southeast winds 5-10 knots. Low confidence. && .MARINE... Small Craft Advisory continues through Wednesday morning for the New Jersey and Delaware Atlantic coastal waters. Northeast or east winds will gust 20-25 knots into tonight, however a diminishing trend is expected through Wednesday. However, seas in the 4-6 foot range will take some time to subside. The conditions are anticipated to remain below Small Craft Advisory conditions on Delaware Bay. Outlook... Wednesday night through Sunday...The conditions are anticipated to be below Small Craft Advisory criteria. Rip currents... For Wednesday, north or northeast winds 10-20 mph will diminish some during the afternoon. A medium to long period (around 8 to 9 seconds) northeasterly swell and breaking waves of 2-4 feet results in a HIGH risk for the development of dangerous rip currents for the New Jersey shore near and north of Long Beach Island (where beaches are more north/south oriented) and for the Delaware Beaches. For Atlantic and Cape May County beaches, the more offshore wind and northeast swell should preclude a higher risk, and thus a MODERATE rip of rip currents is expected there. For Thursday, the northeasterly swell and seas will be considerably less than Wednesday along with smaller breaking waves of 1 to 2 feet. This combined with a west to southwest wind should result in a LOW rip of rip currents for New Jersey. A MODERATE risk of rip currents is expected for the Delaware Beaches where a slightly higher northeasterly swell and seas are expected to linger longer during the first half of the day. && .TIDES/COASTAL FLOODING... Onshore flow continues through late Wednesday then becomes southerly on Thursday. This may result in some spotty minor tidal flooding around the time of high tide tonight and Thursday, especially for coastal New Jersey. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...High Rip Current Risk from 8 AM EDT Wednesday through Wednesday evening for NJZ014-026. DE...High Rip Current Risk from 8 AM EDT Wednesday through Wednesday evening for DEZ004. MD...None. MARINE...Small Craft Advisory until noon EDT Wednesday for ANZ450>455. && $$ Synopsis...Fitzsimmons/Wunderlin Near Term...Davis/Gorse Short Term...Fitzsimmons/Franklin Long Term...Wunderlin Aviation...Davis/Franklin/Gorse/Wunderlin Marine...Franklin/Gorse/Staarmann/Wunderlin Tides/Coastal Flooding...WFO PHI FXUS61 KPHI 170151 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 951 PM EDT Tue Aug 16 2022 .SYNOPSIS... Surface low pressure offshore to the east swings north and northwestward through Thursday before pushing out to the northeast thereafter. Weak high pressure builds in Friday and remains generally over the region through Sunday while a surface low to the south tracks to the northeast. A frontal boundary approaches from the west and could affect the area early next week. && .NEAR TERM /THROUGH WEDNESDAY/... A quiet evening as an upper low pivots over the area, with a shortwave on its eastern flank fueling a weak coastal low over the open Atlantic. This has sparked a thunderstorm complex over the open waters this afternoon and evening, but dry weather has prevailed over our region with less favorable lift on the backside of this weak shortwave. Another shortwave looks to pivot around the low tomorrow, which may lead to a few more showers and thunderstorms, though nothing widespread by any means, but we will take what we can get precipitation-wise. A closed low remains over our area through tonight before it shifts northeastward during Wednesday. Given the positioning of the closed low, our region is sitting beneath an area nearly void of large scale ascent. The forcing for ascent is focused around our forecast area and also closer to an offshore surface low. Any shower activity has been to our west, with a compact cluster of convection well offshore associated with a surface low. While an isolated shower could still occur through early this evening, this may occur only around the Pocono region and therefore slight chance PoPs were retained there. A few showers attempted to form over an area of convergence off the Cape May coast earlier this afternoon but have dissipated with sunset approaching. Kept PoPs in slight chance range offshore a little longer in case anything attempts to form as a cumulus field still exists. The northeast to east wind 10-15 mph with gusts to around 25 mph range (strongest closer to the coast) will diminish as we go into this evening. Temperatures will fall back into the 60s and 50s tonight overall. As we go through Wednesday, the center of the closed low is forecast to be shifting to our northeast. This will place our region more into cyclonic flow aloft with some shortwave energy moving through. Meanwhile, surface low pressure well offshore will be making its way northward toward the New England coast by days end. The bulk of the shortwave energy and lift should become more focused to our north and northeast as the closed low starts to capture the surface low. While a few showers or a low-topped thunderstorm cannot be ruled out primarily during Wednesday afternoon, it looks mostly isolated. Pinpointing where any showers will develop is more challenging in setups like these, however any development may be more tied to terrain areas or differential heating boundaries. Therefore, placed the low mentionable PoPs in some of our western and northwestern areas. The surface flow will be initially out of the northeast Wednesday, although as the surface low tracks closer to coastal New England the winds across our area should back and weaken some. As a result, it maybe a little breezy along the coast to start it should then lessen by late afternoon. The diminishing wind speeds may result in a sea breeze with winds shifting from the east and southeast. Inland, the surface winds may start to turn from the north and northwest during the afternoon. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... A closed low is forecast to lift northeastward into New England and eastern Canada Wednesday night into Friday. Given the positioning of the closed low, our region looks to sit beneath an area nearly void of large scale ascent. It looks like the forcing for ascent is focused around our forecast area and also closer to an offshore surface low. While a few showers or low- topped thunderstorms cannot be ruled out primarily during the peak heating hours, it looks to be rather isolated at best. Any convective development may be more tied to terrain areas or differential heating boundaries. The surface winds weaken Thursday as they becomes east to southerly. Temperatures are forecast to be roughly around average for this time of year with relatively low humidity levels through the period. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... Guidance indicates overall good consistency in the general upper level pattern and its evolution during the long range period. The start of the period sees upper level low pressure in place to our west while upper level high pressure is in place to our north and southeast. This upper level pattern generally holds firm in the following days with not much overall change in upper level features occurring. The ensembles break down the trough to the west and ridge to the southeast some during the Monday and Tuesday timeframe all while the trough to the west and ridge to the north move eastward. At the surface we see weak surface low pressure to our south with weak high pressure generally over our region to start the period. High pressure remains over the region through Sunday though guidance indicates a few isolated showers or storms cannot be ruled out for Saturday and Sunday. Saturday and Sunday see above normal temperatures in the upper 80s and in some locations possibly the low 90s. A frontal boundary looks to approach Monday with widespread showers and thunderstorms possible during the Monday night/Tuesday morning timeframe as the front passes through. Another frontal boundary looks to approach from the west thereafter but confidence in the timing and impacts of this boundary is currently low. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...VFR. East to southeast winds turning light to the northeast and perhaps variable after 03Z. Moderate confidence. Wednesday...VFR. An isolated afternoon shower or thunderstorm possible mainly north and west of the I-95 corridor terminals. Light and variable winds becoming north-northeast around 10 knots, then turning north or northwest during the afternoon at some terminals. A sea breeze could develop and turn the winds east to southeast at ACY. Low confidence on the wind direction details. Outlook... Wednesday night...VFR. Winds becoming light and variable. Moderate confidence. Thursday and Friday...Mainly VFR. Light and variable winds becoming west to southwest around 5 knots Thursday, then south or southeast 5- 10 knots Friday. Moderate confidence. Saturday...Mostly VFR however there is a chance of some showers. Southeast winds 5-10 knots. Low confidence. Sunday...Some times of sub-VFR conditions possible with a chance of some showers. Southeast winds 5-10 knots. Low confidence. && .MARINE... Small Craft Advisory continues through Wednesday morning for the New Jersey and Delaware Atlantic coastal waters. Northeast or east winds will gust 20-25 knots into tonight, however a diminishing trend is expected through Wednesday. However, seas in the 4-6 foot range will take some time to subside. The conditions are anticipated to remain below Small Craft Advisory conditions on Delaware Bay. Outlook... Wednesday night through Sunday...The conditions are anticipated to be below Small Craft Advisory criteria. Rip currents... For Wednesday, north or northeast winds 10-20 mph will diminish some during the afternoon. A medium to long period (around 8 to 9 seconds) northeasterly swell and breaking waves of 2-4 feet results in a HIGH risk for the development of dangerous rip currents for the New Jersey shore near and north of Long Beach Island (where beaches are more north/south oriented) and for the Delaware Beaches. For Atlantic and Cape May County beaches, the more offshore wind and northeast swell should preclude a higher risk, and thus a MODERATE rip of rip currents is expected there. For Thursday, the northeasterly swell and seas will be considerably less than Wednesday along with smaller breaking waves of 1 to 2 feet. This combined with a west to southwest wind should result in a LOW rip of rip currents for New Jersey. A MODERATE risk of rip currents is expected for the Delaware Beaches where a slightly higher northeasterly swell and seas are expected to linger longer during the first half of the day. && .TIDES/COASTAL FLOODING... Onshore flow continues through late Wednesday then becomes southerly on Thursday. This may result in some spotty minor tidal flooding around the time of high tide tonight and Thursday, especially for coastal New Jersey. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...High Rip Current Risk from 8 AM EDT Wednesday through Wednesday evening for NJZ014-026. DE...High Rip Current Risk from 8 AM EDT Wednesday through Wednesday evening for DEZ004. MD...None. MARINE...Small Craft Advisory until noon EDT Wednesday for ANZ450>455. && $$ Synopsis...Fitzsimmons/Wunderlin Near Term...Davis/Gorse Short Term...Fitzsimmons/Franklin Long Term...Wunderlin Aviation...Davis/Franklin/Gorse/Wunderlin Marine...Franklin/Gorse/Staarmann/Wunderlin Tides/Coastal Flooding...WFO PHI
Office: PBZ FXUS61 KPBZ 170456 AAB AFDPBZ Area Forecast Discussion...UPDATED National Weather Service Pittsburgh PA 1256 AM EDT Wed Aug 17 2022 .SYNOPSIS... Periodic showers and perhaps a thunderstorm chances will continue until dry conditions return later in the week with building high pressure. && .NEAR TERM /THROUGH TODAY/... Isolated to scattered showers will continue with shortwave provided ascent within upper troughing. No change in the weather expected today as the low/trough remains near the nern CONUS. As such; continued scattered showers, peaking in coverage during the afternoon and evening with diurnal instability. An isold aftn/eve tstm is possible, though instability should remain limited. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... The trough should begin to fill and track ewd tonight in the main flow aloft, with shortwave ridging supporting a reduction in widespread precipitation chances by Thursday. This will also support temperature moderation toward average values. Dry weather should return Friday as the trough exits, and shortwave ridging builds across the Upper Ohio Valley region. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The next trough is progged to dig across the Midwest/Great Lakes region over the weekend as it approaches the Upper Ohio Valley region. Increasing moisture and shortwave supported ascent in SW flow ahead of the trough should return scattered showers to the region for the weekend, with seasonable temperature persisting through the period. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... Sct shra and lcl restrictions wl continue overnight with a mid/upr low centered across PA. There could be some patchy fg twd morning, though mid lvl clouds should limit this potential. If clearing occurs fg wl become likely in areas where rain fell this eve. After any morning fg, VFR is expected Wed with stratocu/altocu cigs. Sct shra and a psbl tstm are expected again with the area in close proximity to the upr low, and as convective temperatures are reached. This activity should wane Wed eve as the upr low begins to shift newd. .Outlook... Restriction potential returns Sat and Sun with approaching low pres. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION...