textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

Increased chance for isolated showers and storms Monday and Tuesday afternoons.

KEY MESSAGES

1. High pressure will slowly build towards the region through Wednesday.

2. A warm front on Thursday, will be followed very closely by a cold front Friday into Saturday, resulting in unsettled weather at the end of the week.

DISCUSSION

KEY MESSAGE 1...High pressure will slowly build towards the region through Wednesday.

High pressure is expected to slowly build towards the region. However, the main mid and upper level low which was responsible for the unsettled weather over the past few days, will still be centered over Ontario and Quebec through tomorrow. As a result, we could continue to see some isolated showers and storms, particularly in the afternoon hours as embedded short wave troughs pivot through the region through Tuesday before the main low finally starts to lift northeast away from the region. At this point, main concerns with any storms are cloud-to-ground lightning and brief heavy downpours, but the risk for other hazards is quite low.

KEY MESSAGE 2...A warm front on Thursday, will be followed very closely by a cold front Friday into Saturday, resulting in unsettled weather at the end of the week.

By Thursday, high pressure moves offshore with southerly return flow behind a warm front, helping bring dew points back into the low-70s. There looks to be two chances for showers and storms. The first is expected to be Thursday with and behind the warm front. Another chance for storms is possible Friday into Saturday as a cold front approaches. The timing of this cold front will be critical in the risk for thunderstorm hazards, so uncertain on the severe and flooding risk at this point, but will continue to monitor as we go through the week.

AVIATION /06Z MONDAY THROUGH FRIDAY/

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

Through Today...Primarily VFR conditions expected. Isolated SHRA and TSRA are possible, particularly from KABE to KTTN and northward, but coverage is expected to be limited so confidence is too low to include in the TAFs at this point. W to WSW winds around 10 kts gusts up to 15-20 kts. Winds shifting more north of west toward 00Z. High confidence.

Tonight...Prevailing VFR conditions expected. Winds mostly out of the west, but becoming light and variable, particularly after 00Z.

Outlook...

Tuesday and Wednesday...VFR expected most of the time.

Thursday and Friday...Showers and thunderstorms likely developing late, otherwise prevailing VFR.

MARINE

No marine hazards expected.

Outlook...

Through Wednesday...No marine hazards expected.

Thursday and Friday...Gusts near 25 kt are possible, particularly on Thursday with southerly winds behind a warm front.

Rip Currents...

On Monday, southwest winds will average 10 to 15 mph with gusts up to 20 mph in the afternoon with breaking waves of 1 to 2 feet. There will be light southerly swells with a period of 6 to 8 seconds. As a result, there is a LOW risk for the development of dangerous and life threatening rip currents at the Jersey Shore and at Delaware Beaches.

On Tuesday, winds will shift more westerly with similar seas and surf conditions as Monday expected. As a result, there is a LOW risk for the development of dangerous and life threatening rip currents at the Jersey Shore and at Delaware Beaches.

For specific beach forecasts, visit weather.gov/beach/phi

PHI WATCHES/WARNINGS/ADVISORIES

PA...None. NJ...None. DE...None. MD...None. MARINE...None.