textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

No significant changes.

KEY MESSAGES

1. A HIGH risk of rip currents will create dangerous conditions at the Jersey Shore and Delaware Beaches through Monday.

2. Unsettled weather continues through Memorial Day as a sequence of fronts and areas of low pressure move through the area. Drier and more seasonable weather returns by mid-week.

DISCUSSION

KEY MESSAGE 1...A HIGH risk of rip currents will create dangerous conditions at the Jersey Shore and Delaware Beaches through Monday.

The rip current statement was extended until 8 PM Monday as we expect a HIGH risk of rip currents to persist through this time.

For Monday, winds will be out of the south to southwest at 10 to 15 mph with gusts up to 20 mph. Breaking waves will be 2 to 4 feet. There will be multiple swell groups including an easterly swell with a 9 second period which will lead to the continuing HIGH risk for dangerous and life threatening rip currents.

KEY MESSAGE 2...Unsettled weather continues through Memorial Day as a sequence of fronts and areas of low pressure move through the area. Drier and more seasonable weather returns by mid-week.

An area of low pressure over the eastern Great Lakes will track northeast into western New York tonight. As it does so, it will cause the stationary boundary which is currently draped over the East Coast to move northward as a warm front later tonight. However, it is worth noting that the CAD wedge is quite strong and is still located as far south as northern Georgia and South Carolina at this hour. It will take a quite a substantial surge north to reach and pass through our area overnight. With this in mind, temperatures are expected to remain on the cooler side of things tonight with temps mainly in the 50s and 60s. Spotty drizzle, mist, and fog are likely to continue through tonight. There is the potential for dense fog overnight. A Dense Fog Advisory has been issued for Carbon and Monroe counties until 10 AM Monday.

By early tomorrow morning, the low pressure system will be tracking across the Northeast. A trailing cold front will be approaching the area from the west accompanied with some shortwave energy aloft. Latest trends suggest that the front will be a bit slower to arrive than previously anticipated, so the next round of rain is now not expected to arrive until the pre-dawn hours on Monday and continue through much of the day from northwest to southeast. Widespread showers are likely, with embedded thunderstorms possible, especially south and east of the I-95 corridor and across the Delmarva. The severe risk looks quite low, but cannot rule out a stray gusty storm. Again, this is all dependent on how far north the warm front gets, and will also determine the temperature forecast for Memorial Day. Highs for Memorial Day will mainly be in the low to mid 70s despite abundance of clouds, but could be a few degrees warmer/cooler depending on warm frontal progression. Showers will wane by Monday evening for most, except across far southern New Jersey and across the Delmarva where showers may continue into Tuesday. Additional rainfall totals will generally range from 0.25- 0.50 inches for most, with the exception of the Delmarva and Cape May County where an additional 1-2 inches of rain is possible.

By mid to late week, a more seasonable, dry and benign weather pattern takes shape as high pressure returns to the area.

AVIATION /01Z MONDAY THROUGH FRIDAY/

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

Tonight...Low ceilings and visibility restrictions continue. IFR to LIFR expected overnight. A few showers possible after 06Z for KABE/KRDG. Shower coverage looks to increase between 09Z-12Z Winds become light and variable overnight. Low confidence.

Monday...IFR to LIFR in the morning with low ceilings and visibility restrictions. There is some improvement between 16Z-18Z to IFR or MVFR as ceilings lift a bit. KMIV/KACY may stay IFR to LIFR through the day. Showers move through during the morning and end for most terminals in the afternoon. Rain showers look to persist at KMIV and KACY through the remainder of the day. Light winds in the morning become more out of the southwest to west in the afternoon. Low confidence.

Outlook...

Tuesday...Mainly VFR. A few showers possible.

Wednesday thru Friday...Mainly VFR.

MARINE

A continuation of the pattern with high pressure offshore and a lingering front along the shore areas. Weak low pressure moves through Monday and it will be followed by a cold front later Monday. We'll continue with the SCA flag tonight and since it'll take awhile from the seas to settle, we'll continue it into Monday. Seas on the ocean mostly around 5 ft.

The Dense Fog Advisory has been extended to include the Atlantic Coastal waters from Sandy Hook to Little Egg Inlet and also the upper Delaware Bay until 11 AM Monday. The remainder of the Dense Fog Advisory remains unchanged and also goes through 11 AM Monday.

East to Southeast winds this evening turn south around 10 kts later tonight, but seas remain elevated, gradually subsiding to 4 to 5 feet late. The Small Craft Advisory remains in effect for the ocean waters through tonight. Drizzle and a few showers expected.

On Monday, winds will begin the day from the south around 5 to 10 knots but then switch to Southwest by afternoon speeds will become 10 to 15 kts. The SCA will continue for seas since gusts will likely be 20 kts at most. Showers expected with a chance for a tstm.

Outlook...

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

Rip Currents...

The rip current statement was extended until 8 PM Monday as we expect a HIGH risk of rip currents to persist through this time.

For Monday, winds will be out of the south to southwest at 10 to 15 mph with gusts up to 20 mph. Breaking waves will be 2 to 4 feet. There will be multiple swell groups including an easterly swell with a 9 second period which will lead to the continuing HIGH risk for dangerous and life threatening rip currents.

For Tuesday, winds will shift to the southeast but diminish to around 5 to 10 mph. Wave heights should subside slightly as well but there will continue to be an easterly swell around 8 to 9 seconds. For these reasons, there is a MODERATE risk for the development of dangerous and life threatening rip currents.

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

PHI WATCHES/WARNINGS/ADVISORIES

PA...Dense Fog Advisory until 10 AM EDT Monday for PAZ054-055. NJ...High Risk for Rip Currents through Monday evening for NJZ014- 024>026. DE...High Risk for Rip Currents through Monday evening for DEZ004. MD...None. MARINE...Dense Fog Advisory until 11 AM EDT Monday for ANZ430-431- 450>455. Small Craft Advisory until 6 PM EDT Monday for ANZ450>455.