textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

No significant changes made to the forecast.

KEY MESSAGES

1. One last day of unsettled weather before a tranquil stretch takes over.

2. A frontal system on Sunday and Monday will bring the next chance for showers and thunderstorms after today.

DISCUSSION

KEY MESSAGE 1...One last day of unsettled weather before a tranquil stretch takes over.

A closed low over the north continues to slowly move off to the east/northeast, with our area remaining under cyclonic flow. Another shortwave will rotate through later this afternoon, triggering another round of scattered showers and isolated thunderstorms this afternoon. Not expecting any severe weather or flooding concerns overall though and this should be the final day of active and unsettled weather until Sunday. Some areas likely stay dry as the surface low slowly pulls away. Thinking a large majority of showers will be east of a line from Cape May to Philadelphia to Mount Pocono. Temperatures will continue to be below normal for late July, topping out in the upper 70s/low to mid 80s.

High pressure moves in tonight, with a stretch of dry weather expected through Saturday Night. Temperatures begin to moderate towards seasonal averages as we get into the end of the week and into the weekend.

KEY MESSAGE 2...A frontal system on Sunday and Monday will bring the next chance for showers and thunderstorms after today.

High pressure weakens late Saturday and is replaced by advancing low pressure from the Ohio Valley area. This low strengthens and moves west of our area later Sunday and into Monday. Thus system will bring increasing chances for showers and a few tstms Sunday afternoon for the western counties and all areas Sunday night and Monday. The PWAT values off the forecast soundings during these times show more 2+ inch PWAT values for our region. So it's possible that excessive rainfall may develop for parts of the region. Moisture and instability will also increase ahead of the front, so we likely will have to monitor the severe weather threat for the Sunday and Monday afternoon period. However, our area is not in any long term outlooks, so there is a chance that there are more hydro concerns with this system.

AVIATION /07Z THURSDAY THROUGH MONDAY/

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

Rest of Tonight (through 12z)...VFR. Thinking MVFR CIGs hold off until after 12z. West/northwest winds 5 to 10 kt. Moderate confidence.

Today...VFR conditions should transition to MVFR as some lower CIGs rotate in from the northwest, sometime between 12z-14z and continue through 16z-18z. Similar to yesterday, a few showers and isolated thunderstorms could pop up, but coverage should be limited and chance of SHRA/TSRA is low enough at all terminals to not include at the TAF at this time. Winds will increase around 12z-14z with 10-15 kt and gusts 20 to 25 kt out of the northwest before diminishing between 19z-21z. A sea-breeze at KACY could turn winds more easterly after 20z-21z. Low confidence.

Thursday Night...VFR. Winds light and variable at 5 kt or less though a northerly direction may be favored at times. High confidence.

Outlook...

Friday through Saturday Night...VFR. No significant weather.

Sunday through Monday...Primarily VFR but a frontal system will slowly move through the area Sunday into Monday, likely (50-70% probability) resulting in restrictions at times over this period.

MARINE

Tranquil conditions on the waters expected through tonight with northwest winds around 5 to 15 kt and seas 2 to 3 feet.

Outlook...

Thursday night through Sunday...No marine headlines expected.

Sunday Night through Monday...SCA conditions possible (20-30%) as seas could near 5 feet.

Rip Currents...

For today, northwest winds 15 to 20 mph with breaking waves around 2 feet or less and a weak 2 foot 8 second southeasterly swell. While the Full Moon was on Wednesday, decreasing wave heights, more offshore flow, and minor 8 second swell should limit the rip current threat. As a result, elected for a LOW risk for rip currents at all beaches.

For Friday, light westerly winds around 5 to 10 mph will give way to a southeasterly seabreeze around 10 mph. Breaking waves linger around 2 feet or less with a 2 foot 8 second southeasterly swell. Forecasting a LOW risk for rip currents at all beaches.

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

PHI WATCHES/WARNINGS/ADVISORIES

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