textproduct: Philadelphia/Mt Holly

SYNOPSIS

Strong low pressure moves into the Canadian Maritimes tonight and into Monday. High pressure slides by to our south later Tuesday, then weak low pressure tracks eastward from the Ohio Valley to the Mid-Atlantic Tuesday into Wednesday. A warm front lifts north across our region Thursday night and Friday, followed by a weak cold front Friday night. A secondary cold front may move through Saturday night.

NEAR TERM /THROUGH MONDAY/

Tonight, the dry Northwest to West flow continues across the area with gusts 45 to 50 mph at times. Th gusts will slowly subside this evening to 25 to 35 mph but after that, gusts will likely remain at least 20 mph for the overnight. While most areas have been dry, a couple sprinkles and flurries (afr NW) continue. These will remain into the evening before diminishing overnight. Lows tonight will drop into the 30s with some upper 20s for the NW areas. Winds chills will make conditions feel like the 20s (teens N/W).

On Monday, our area will continue to be on the North/northeast periphery of the approaching high pressure system. This will continue to cause a Northwest flow of dry air to be across the Middle Atlantic region. Winds will not be as gusty as on Sunday, but gusts 20 to 30 mph will develop by afternoon. High temperatures will range from the low 40s for the north most counties to the mid/upper 40s for Delmarva and south NJ.

SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/

Cold air continues to filter in Monday night through Tuesday night. This is with a mainly west to west-northwest wind as we are in the cyclonic flow of a low pressure system well to the north near the Canadian Maritimes. There will be a high pressure system building into the region which also leads to a tighter pressure gradient that relaxes more through the day Tuesday and into Tuesday night. In terms of temperature, lows are in the mid 20s to low 30s Monday night and upper 20s to upper 30s Tuesday night. Our highs on Tuesday are in the low 40s to low 50s and mid 40s to mid 50s Wednesday. For winds, gusts upward of 20-30 mph Monday night trend lower into Tuesday with gusts 15-25 mph as the pressure gradient lessens.

We do not see too much in the form of cloud cover Monday night with more clouds filtering in throughout the day Tuesday. Precip looks pretty minimal Monday night into the first half of Tuesday. The only exception would be any lingering snow showers due to the lake effect upstream. However, this looks limited at this time with the best potential being in the Poconos. Due to the limited potential, PoPs were kept below mentionable.

By Tuesday afternoon into Tuesday night, we see a low pressure system that starts to enter the region from the west. This low pressure system looks to be on the weaker side. Given the expected track being more southerly, the best potential for any rain is in Delmarva, parts of southeast Pennsylvania, and southern New Jersey. As you get closer to I-78 and north, the potential for precip lessens to 20-40%. There is less confidence on precip making it as far as I-80 or even north of this area where PoPs are 20-30%. One key note is that if precip does make it that far north, some light snow or a rain/snow mix can be expected at times Tuesday night, especially for the Poconos and Sussex county New Jersey. Any precip does look to end on Wednesday morning and we trend drier through the day with a partly to mostly cloudy sky.

LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/

In the long term period, we do have more opportunities for precipitation and temperatures moderate. There is the potential for an isolated shower Wednesday night into Thursday with a piece of upper-level energy moving through. Overall, not much precipitation expected for that timeframe but we do stay mainly mostly cloudy. Highs on Thursday are in the mid 40s to upper 50s. By Thursday night, a warm front lifts northward leading to some showers being possible Thursday night into Friday morning. The better potential for any rain associated with this system looks to be ahead of the cold front during the day Friday into Friday night. The cold front will pass through the area overnight Friday. Due to the warm front Thursday night, we do trend warmer Friday with highs in the mid 50s to mid 60s.

The unsettled weather continues into Saturday with another potential for rain during the day Saturday into Saturday night. This is with a secondary cold front. Overall details are less certain with this cold front due to timing, track, and intensity of the low pressure system that this front is attached to. Right now, PoPs are at slight chance to chance for this time period. Highs on Saturday are in the mid 50s to mid 60s.

AVIATION /19Z SUNDAY THROUGH FRIDAY/

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

Tonight... VFR expected. Sky cover mostly sct050-060 with bkn conditions for KABE/KRDG. A few stray showers for (mostly) KRDG/KABE possible thru this evening but confid remain low about that. West to Northwest winds 20 to 30 kts with gusts around 40 kts until early evening the decreasing gusts overnight. Medium/High confid.

Monday... VFR conditions expected with sct-bkn 050 cloud cover expected most sites. Gusty W to NW winds probable again. Gusts Monday will not be as high as Sunday with mostly 20 to 25 kts. Medium/high confid.

Outlook...

Monday night...VFR. Gusty winds diminishing.

Tuesday...Areas of sub-VFR conditions possible at night due to some rain, especially south of KPHL.

Wednesday and Thursday...Mainly VFR.

Friday...Sub-VFR conditions possible with rain moving through the area Friday and Friday night.

MARINE

No changes were made to the ongoing Gale flags across the waters. Gusts may decease below Gales for a period overnight, but more Gale gusts are expected Monday. We'll continue to run the Gales into Monday. West to Northwest winds with gusts 35 to 40 kts. Fair weather tonight and Monday.

Outlook...

Monday night...Small Craft Advisory conditions, especially during the evening.

Tuesday through Thursday...The conditions are anticipated to be below Small Craft Advisory criteria.

Friday...Small Craft Advisory conditions possible Friday and Friday night with an increasing SW wind to near 25 knots and seas building to near 5 feet.

FIRE WEATHER

Strong west to northwest wind has developed with speeds generally at 20 to 30 mph with 35 to 45 mph gusts. Min RH Values will be 35 to 40 percent, but may be as low as 30 to 35 percent across Delmarva. A Special Weather Statement for the eastern shores of Maryland was issued earlier.

PHI WATCHES/WARNINGS/ADVISORIES

PA...Wind Advisory until 7 PM EST this evening for PAZ060>062-070- 071-101>106. Wind Advisory until 1 AM EST Monday for PAZ054-055. NJ...Wind Advisory until 7 PM EST this evening for NJZ001-007>010- 012-013-015>022-027. Wind Advisory until 10 PM EST this evening for NJZ014-023>026. DE...Wind Advisory until 7 PM EST this evening for DEZ001>003. Wind Advisory until 10 PM EST this evening for DEZ004. MD...Wind Advisory until 7 PM EST this evening for MDZ012-015-019- 020. MARINE...Gale Warning until 6 PM EST Monday for ANZ430-431-450>455.