textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

Updated Aviation discussion for 06z TAFs.

KEY MESSAGES

1. Low pressure and its associated fronts will cross the area this evening into early Thursday.

2. A storm system tracks close to our area from the south Saturday, bringing a potential for rain.

DISCUSSION

KEY MESSAGE 1...Low pressure and its associated fronts will cross the area this morning.

Low pressure and its associated cold front are crossing Pennsylvania early this morning. It'll continue eastward so that the front will be off the NJ/DE shore areas later this morning.

Much of the rain has already occurred but scattered showers through dawn will add a bit to the totals. Patchy fog is possible during the pre-dawn hours before drier air arrives on a gusty NW winds. A couple widely scattered showers later today are possible too, probably mostly across the far NW areas.

KEY MESSAGE 2...A storm system tracks close to our area from the south Saturday, bringing a potential for rain.

As a closed low remains across southeastern Canada over the weekend, a stronger shortwave is forecast to rotate through the base of it from the Ohio Valley to the Mid-Atlantic then offshore. This feature should support surface low development, however the model guidance varies on the placement of this low. Some models and ensembles have this low stronger and farther to the north, which would bring a shield of rain across most of our area. Some other guidance, including the GFS, are weaker and farther south with the surface low. Despite the uncertainty with the location/track of the surface low, given the synoptic setup suggests that whatever system occurs would tend to be a quick mover. Also, given the presence of the closed low, temperatures will be chilly over the weekend (well below average) with Saturday being the coolest.

AVIATION /06Z THURSDAY THROUGH MONDAY/

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

Overnight...Lower CIGS/VSBYs in showers for the next few hours then the rains will end from West to East. Lower CIGS will continue into dawn before drier air arrives and brings slow improvement from NW to SE. Light winds then NW winds 5 to 10 knots late. Medium confid overall.

Thursday...MVFR/IFR cigs to start but conditions improve through the morning with all sites expected to be VFR by around midday. VFR. NW wind generally around 10 to 15 knots with gusts up to 25 knots.

Outlook...

Thursday night...VFR. Northwest wind 10 to 15 knots.

Friday...VFR. West-northwest wind gusts up to 20 knots during the day.

Saturday...A period of sub-VFR and showers possible.

Sunday and Monday...Mainly VFR.

MARINE

Sub-SCA conditions expected through overnight. Winds will be mainly SE 10 to 15 kts into the early overnight period. Winds will then turn SW followed by a further turn to NW around dawn. Low-end SCA gusts possible, but not certain. Showers through the overnight becoming more scattered by dawn. Confidence is low for SCA conditions on Thursday with mainly 3 to 5 ft seas.

Outlook...

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

PHI WATCHES/WARNINGS/ADVISORIES

PA...Coastal Flood Advisory until 5 AM EDT early this morning for PAZ070-071-106. NJ...Coastal Flood Advisory until 5 AM EDT early this morning for NJZ017>019. DE...None. MD...None. MARINE...None.