textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

Winds continue to diminish. The High Surf and High Rip Current products have been discontinued.

KEY MESSAGES

- 1) The nor'easter will continue to spin over the forecast area before slowly departing on Monday and Tuesday.

- 2) Coastal flooding threat lowered in many areas but still a concern along the back bays of New Jersey and Delaware.

- 3) Dangerous rip currents and surf threats have diminished.

- 4) A cold front is likely to cross through the region Friday into Saturday.

DISCUSSION

KEY MESSAGE 1...The nor'easter will continue to spin over the forecast area before slowly departing on Monday and Tuesday.

Broad high pressure remains centered over eastern Canada and extends back into the Great Lakes. Pressure gradient over our region continues to decrease as the low continues to fill and weaken. Expect that trend to continue. Therefore, the remaining wind advisory has been allowed to expire.

As we move through the overnight, PoPs will be highest across New Jersey and east-central Pennsylvania. Another round of rain is developing offshore and will rotate in later this afternoon and tonight. As a result, I have categorical PoPs across this area. I have a range of PoPs elsewhere ranging from slight chance across our southern Delmarva zones to likely across the southern Poconos.

As both the surface high to our north and the low itself weakens, there will be a noticeable drop off in winds overnight.

KEY MESSAGE 2... Coastal flooding threat lowered in many areas but still a concern along the back bays of New Jersey and Delaware.

The Nor'easter has moved onshore across New Jersey as of Sunday afternoon. This has caused winds to remain onshore across the northern NJ coastal areas (Monmouth and Middlesex counties) while winds across southern NJ and Delaware have turned offshore and will remain that way tonight and Monday. The effects of the weakening storm and changing winds will allowed tidal departures to lower across Cape May and Atlantic counties, so we have dropped the Coastal Flood Warning in these areas. it appears right now that no additional coastal flooding will occur in these areas.

Further north,the onshore flow and continued effects of the Nor'easter will keep high tides tonight and Monday morning at Minor flooding levels. For those areas, we have dropped the Coastal Flood Warning and replaced it with an Advisory into Monday morning. One exception, is Ocean County NJ, where we have kept the Coastal Flood Warning with the effects of high water in the back bays continuing. The warning presently goes until Monday 2 PM, but may need to be extended. High water for back Bays across Southern Delaware are a concern too, so a Coastal Flood Warnings for Sussex County Delaware is in effect until Monday 2 PM.

For Delaware Bay communities, a strengthening Northwest wind will remain across Delaware Bay into tonight. This will promote lowering tidal departures as the waters is pushed down/out Delaware Bay. As a result, additional flooding (at high tides) will be spotty Minor or less. No additional flags for tidal flooding are expected.

For the tidal Delaware River, the North to Northeast flow has kept water levels (at high tide) at the lower part of Minor flooding range. No flags for tidal flooding are expected.

KEY MESSAGE 3...Dangerous rip currents and surf threats have diminished.

The Nor'easter came onshore across NJ earlier today. Behind it the winds and seas have continued to diminish. The seas have dropped to mostly 5 to 6 ft at the buoys as of 5PM. These conditions indicate that High Surf is no longer a threat to the shore areas. While Rip Currents are still present, the strength of these has diminished somewhat too. We are calling for a MODERATE risk for Rip Currents on Monday. Continue to exercise caution if you will be near the ocean tonight and Monday.

KEY MESSAGE 4...A cold front is likely to cross through the region Friday into Saturday.

The surface high that will be over the region for much of the week will start to build southeast and off shore by Thursday. This will open the door for a cold front to sweep through the region Friday or Saturday. Models for the most part, aren't depicting a widespread rain event with this front. However, southwesterly flow on Wednesday and Thursday, should set the stage with ample moisture in place. The biggest question is forcing with this front. The best synoptic scale lift will likely be well removed from the mesoscale forcing associated with the front. For now the 20 to 30 percent PoPs through this period seem appropriate this far out. Preliminary guidance indicates that temperatures behind the front could be 5 to 10 degrees colder than normal.

AVIATION /22Z SUNDAY THROUGH FRIDAY/

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

Tonight...Continued MVFR/IFR conditions in lingering SHRA. Diminishing winds.

Monday...Conditions improve to MVFR, then to VFR beginning late Monday

Outlook...

Tuesday through Friday...prevailing VFR expected.

MARINE

Winds have begun to decrease slightly. All Storm Warnings have been dropped. Gale Warnings remain up through 6 pm.

Seas have come down but are still rough, as high as 8 to 11 ft. They'll diminish further overnight.

Conditions will continue to improve on Monday. But seas may remain above advisory levels while winds continue to diminish below 25 knots.

Outlook...

Tuesday through Friday...winds and seas should stay below SCA criteria.

Rip Currents...Please see Key Message 3 above.

PHI WATCHES/WARNINGS/ADVISORIES

PA...None. NJ...Coastal Flood Warning until 2 PM EDT Monday for NJZ020-026. Coastal Flood Advisory until 2 PM EDT Monday for NJZ012>014. DE...Coastal Flood Warning until 2 PM EDT Monday for DEZ003-004. MD...None. MARINE...Small Craft Advisory until 10 PM EDT this evening for ANZ430. Small Craft Advisory until 2 AM EDT Monday for ANZ431. Small Craft Advisory until 8 AM EDT Monday for ANZ450>455.