textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

Updated aviation section for 12Z TAFs.

KEY MESSAGES

1. Elevated tide cycles persist due to Post-Tropical Cyclone Josephine well off the coast, resulting in widespread minor coastal flooding continuing in Ocean County, NJ and Sussex County, DE.

2. Frost and freeze impacts possible tonight and Saturday night where the growing season continues.

DISCUSSION

KEY MESSAGE 1...Elevated tide cycles persist due to Post- Tropical Cyclone Josephine well off the coast, resulting in widespread minor coastal flooding continuing in Ocean County, NJ and Sussex County, DE.

As Post-Tropical Cyclone Josephine lingers well off the coast elevated tide cycles are persisting some areas.

In Ocean County, New Jersey and Sussex County, Delaware, water levels remain elevated and minor tidal flooding is continuing, particularly in the back bays. In fact a few locations in the back bays came very close to or even touched moderate levels of coastal flooding yesterday with the high tide. It's going to take some time for water levels to diminish in these areas so we've continued the Coastal Flood Advisory for these counties through this evening. Elsewhere along the Atlantic coast and Delaware Bay any additional coastal flooding looks to be spotty at most.

At this time we are not forecasting any coastal flooding for the Maryland eastern shore.

KEY MESSAGE 2...Frost and freeze impacts possible tonight and Saturday night where the growing season continues.

As an upper-level trough pivots across the Northeast today, a strong mid-level ridge in the Plains to Midwest shifts eastward some into the weekend. This will support strong surface high pressure shifting eastward into the Northeast and Mid-Atlantic through the weekend.

A chilly and dry air mass will accompany this strong surface high, and as the high itself settles more overhead, the winds will decouple. This will set the stage for efficient radiational cooling both tonight and Saturday night. The forecast lows are in the 30s for much of the area (away from the coasts and outside of the urban centers) with a frost and freeze potential. There is some potential for winds to stay a bit elevated tonight so opted to maintain the existing Freeze Watch for locations NW of the I-95 corridor where the growing season remains active. Frost Advisories may be needed outside of these areas for tonight, especially if the radiational cooling ends up being stronger. Another round of near freezing lows is possible Saturday night when additional headlines may be necessary.

AVIATION /09Z FRIDAY THROUGH TUESDAY/

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

Today...VFR. North winds around 7-12 kt will become more easterly late in the day. A few gusts up to 15-20 kt possible. High confidence.

Tonight...VFR. Winds northeast around 5 kts. High confidence.

Outlook...

Saturday through Tuesday...VFR. No significant weather expected.

MARINE

A Small Craft Advisory continues for the New Jersey and Delaware nearshore waters as Post-Tropical Cyclone Josephine gradually moves farther out to sea through the end of the week. A tightened pressure gradient will remain in place however due to strong high pressure to our north. Seas of 5-10 feet on the ocean. The winds and seas are forecast to diminish through today, though seas are currently forecast to remain elevated above 5 feet through tonight and much of Saturday.

Outlook...

Sunday through Monday...The conditions should be below Small Craft Advisory criteria.

Tuesday...SCA conditions possible with seas around 5 feet.

PHI WATCHES/WARNINGS/ADVISORIES

PA...Freeze Watch from late tonight through Saturday morning for PAZ060-061-101-103-105. NJ...Coastal Flood Advisory until midnight EDT tonight for NJZ020- 026. Freeze Watch from late tonight through Saturday morning for NJZ008>010. DE...Coastal Flood Advisory until midnight EDT tonight for DEZ003- 004. MD...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ450. Small Craft Advisory until 6 PM EDT Saturday for ANZ451>455.