textproduct: Philadelphia/Mt Holly

SYNOPSIS

Strong low pressure across the Great Lakes will slowly move across southern Canada tonight and Thursday. An attached cold front will cross the Middle Atlantic tonight. Strong high pressure builds towards the region Friday and Saturday. Another low and front arrive for Sunday and into Monday. Another storm may affect the area towards midweek.

NEAR TERM /THROUGH THURSDAY/

Warm front struggling to push northeastward across the region this afternoon, but likely clears the area towards sunset. This will allow skies to briefly clear as temps briefly warm up to the 60s.

It won't last however, as strong cold front (clearly visible with low-topped squall line across western PA and NY presently) pushes east across the region near or not long after sunset. We'll likely see at least some showers continue across the mountains into our region with the front. Some gusts to 45 mph can't be ruled out with the front, but overall gusts should stay just shy of wind advisory criteria. That said, it may feel like quite a jolt since until the passage, winds will mostly be 10 mph or less. While winds should diminish a bit overnight, expect overall it to remain breezy thru the night, with gusts of 20-25 mph. Skies will partly clear out again post front and temps will rapidly fall, with most areas ending the night in the 30s, 20s in the Poconos.

For Thanksgiving Day, expect breezy/windy and chilly conditions with times of clouds and sun, with greater cloud cover during the afternoon. While it should stay dry, it won't feel very nice with highs only recovering to the low-mid 40s for most, 30s in the Poconos. Westerly winds may gust 30-40 mph during the afternoon.

SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/

Strong high pressure builds towards the area while low pressure exits east out of Canada Thursday night and Friday. The strong pressure gradient between the departing low and high will result in gusty winds across the region both Thursday night and especially Friday. Gusts Thursday night will be around 20-30 mph at times and the gusts will generally be 30 to 40 mph for Friday with some peak gusts up to 50 mph possible.. Wind advisory flags are possible. It will generally be dry except some lake effect snow bands could make it as far south as the southern Poconos Friday afternoon into Friday evening. Any accumulation should be less than 1 inch but the snow showers combined with strong winds could still cause reduced visibility making travel difficult in these areas.

Temperatures will be below normal Thu night/Fri with the colder air from Canada remaining across the region. Highs Fri will mostly be in the low to mid 40s with some 30s for the southern Poconos. Lows will range between 25 and 30 degrees both Thu/Fri nights. Winds will create wind chills as low as the teens to low 20s Thursday night into early Friday.

High pressure builds in right over the area for Saturday which will lead to lighter winds but continuing cool temperatures under partly to mostly sunny skies. Highs will be mainly in the low 40s except some upper 30s in the southern Poconos.

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/

Somewhat milder temps arrive for Sunday and continue into Monday. Highs will be mainly in the 40s to low 50s for Sunday and then back to mainly in the 40s for Monday.

A system passing by to our north could bring mainly some rain for Sunday (POPs around 30 percent south up to 50 percent north) though a Little snow or mixed precip could occur in the southern Poconos. Drier conditions move in on Monday.

Beyond next Monday, there are indications another will likely affect the area around next Tuesday. Chilly air will already have arrived behind the earlier disturbance so temps should already be running a bit below normal for Tuesday but will ultimately be influenced heavily by the track the low takes which will also affect precipitation types. There remains uncertainty in the models at this point given that it's a weak out, but current indications suggest mainly rain or a rain/snow mix is favored near and south of the I-95 corridor with the better chance for some snow accumulating snow being north of there. Again, it's very early and expect changes and refinement to the forecast in the coming days. The system could last into early next Wednesday before drier air moves in by late day.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/

The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Thru tonight....LIFR/IFR slowly improving to VFR towards sunset with southwest winds 5-10 kts. Towards 0Z, gusty westerly winds pick up with the passage of a cold front (which may be accompanied by gusty showers), with 10-20 kt sustained and 20-30 kt gusts developing between 23z and 01z. High confidence in prevailing VFR, though brief reduction in vsby may occur with showers. Moderate confidence in timing of frontal passage.

Thursday...VFR. Gusty westerly winds continue, with gusts closer to 20 kts in the morning and then increasing to near 30 kts in the afternoon. High confidence.

Outlook...

Thursday night through Saturday...VFR. Gusty winds Thu./Fri.

Sunday...sub-VFR possible with clouds and rain arriving.

Monday...Mainly VFR Monday.

MARINE

A Small Craft Advisory is in effect for ocean zones this afternoon and expands to all marine zone tonight through Thursday as a cold front passes in the early-mid evening, with winds ramping up behind the front. Westerly winds after 00z will be around 15-25 kt with gusts around 30 kt. A brief period of gales can't be ruled out near or just after frontal passage. Seas 4 to 6 feet.

Small Craft Advisory conditions continue on all waters Thursday with winds remaining fairly steady, 15-25 kts with gusts up to 30 kts.

Outlook...

Thursday night/Friday... Gale Watch continues with strengthening winds and gusts 35 to 40 kts possible. Fair.

Friday night/Sat... Lowering winds and seas thru the period with sub- SCA by midday Saturday. Fair weather.

Sunday through Monday...Next system could bring another round of SCA conditions Sunday into Sunday night with these condition likely abating by Monday morning.

PHI WATCHES/WARNINGS/ADVISORIES

PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory from 7 PM this evening to 6 PM EST Thursday for ANZ430-431. Gale Watch from Thursday evening through Friday afternoon for ANZ430-431-450>455. Small Craft Advisory until 6 PM EST Thursday for ANZ450>455.