textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

Small Craft Advisory was cancelled with no marine headlines in place for any zone at this time.

Added mention of a slight chance of showers near the coast for this afternoon.

Confidence is increasing in potentially dangerous heat late next week.

KEY MESSAGES

1. Lingering showers and scattered thunderstorms will continue over Delmarva and far South Jersey through the next few hours. Severe weather risk is low however.

2. Primarily dry weather to close out the weekend, though some showers near the coast possible later today.

3. Mainly dry conditions expected through the middle of the week with warming temperatures.

4. Dangerous heat will be possible across the region late this week and into this weekend.

DISCUSSION

KEY MESSAGE 1...Lingering showers and scattered thunderstorms will continue over Delmarva and far South Jersey through the next few hours. Severe weather risk is low however.

The last of the showers and isolated thunderstorms are moving through South Jersey and southern Delaware this morning. They should move off the coast by sunrise. Storms should remain sub- severe with gusts up to 40 MPH possible.

As the initial front goes through, things should dry out pretty quickly. Cannot rule out some patchy fog though in areas that see some rainfall. The drier airmass will hold off until later today.

KEY MESSAGE 2...Primarily dry weather to close out the weekend, though some showers near the coast possible later today.

While the initial cold front is moving offshore at this hour, a secondary front will move through later today, ushering in the cooler and drier airmass. Most areas will stay dry today but some the short range guidance is hinting at some pop up showers along the front as it moves through, mainly along the coast. Not expecting much in terms of rainfall or impacts, but cannot rule out some showers this afternoon near the beaches or perhaps a brief downpour.

With the cooler airmass lagging behind the secondary front, temperatures will still be on the warmer side for most with highs in the mid to upper 80s. Where the front moves through sooner, such as the Poconos and NW NJ, temperatures likely stay in the 70s. Overall, most stay dry today and it should be a nice day to close out the weekend, but cannot rule out some pop up showers near the coastline.

KEY MESSAGE 3...Mainly dry conditions expected through the middle of the week with warming temperatures.

The region will remain embedded within a belt of somewhat enhanced mid-level flow through late Monday as a sharp trough located over New England dives south into the Western Atlantic. Thereafter, mid- level ridging will likely begin to take shape across the region through mid week. At the surface, high pressure in the wake of a cold front will shift into the area, and generally remain in place through Tuesday.

Monday continues to look like a day of relief from the heat, with high temperatures on generally in the mid 70s to low 80s, and temperatures overnight Monday night falling into the low to mid 50s. The cool down does look to be fairly short lived with the high pressure taking shape across the area. Tuesday will be a bit warmer, with temperatures generally climbing into the mid 80s.

Dry conditions are expected through Tuesday night.

KEY MESSAGE 4..Dangerous heat will be possible across the region late this week and into this weekend.

In general, mid-level ridging is expected to remain in place across the region into this weekend, though a few weak disturbances could glance the area. At the surface, high pressure will largely dominate, though it will likely begin to weaken a bit and begin to center more over the southeastern US.

The pattern in place will begin to support daily chances for showers and thunderstorms Wednesday through Saturday, primarily in the form of diurnally driven convection. PoPs through this period are generally 20-40%. Any showers or storms should remain isolated to scattered.

Of greater concern is that this pattern will also favor increasing heat and humidity across the region. Temperatures beginning on Wednesday are likely to be in the low 90s across the region, rising into the mid 90s Thursday into the weekend. With increasing moisture, heat indices could potentially reach or exceed 100 degrees in spots by the weekend. There will be limited relief at night, with lows in the upper 60s to low 70s areawide by late the week and into the weekend. Trends will continue to be monitored as this level of heat could ultimately necessitate the need for heat headlines across parts of the region should it materialize.

AVIATION /06Z SUNDAY THROUGH THURSDAY/

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

Through 12z...Primarily VFR. Cannot rule out some brief periods of patchy fog especially over areas that got a decent amount of rain earlier. Probability of fog is only around 10% though and should only drop things down to MVFR at worst. Any remaining showers/thunderstorms should remain south of all TAF sites. Winds light out of the southwest around 5 to 8 kt. Moderate confidence.

Today...VFR. West/northwest winds around 5 to 10 kt will increase to around 10-15 kt with gusts 20-25 kt between 14z-16z. Moderate confidence.

Tonight...VFR. North/northeast winds around 5 to 10 kt. High confidence.

Outlook...

Monday through Tuesday night...VFR. No significant weather.

Wednesday/Thursday...Primarily VFR. Brief periods of sub-VFR conditions can't be ruled out in isolated to scattered afternoon showers tstms.

MARINE

The Small Craft Advisory was cancelled a few hours early, and sub-SCA conditions are expected through tonight. Winds out of the southwest today around 10-15 kt, becoming north/northeasterly tonight around 10-20 kt. Seas of 2 to 3 feet are expected.

Outlook...

Monday through Tuesday night: No marine headlines are currently anticipated with winds under 25 kt and seas under 5 feet.

Wednesday through Wednesday night...SCA conditions are possible with south winds of 15-20 kt and gusts near 25 kt. Seas could approach 5 feet.

Thursday...No marine headlines currently anticipated with winds under 25 kt and seas under 5 feet.

Rip Currents...

For today, west-northwest winds of 5-15 mph, becoming more northwesterly in the afternoon. Breaking waves will be 2-3 feet. There may be an increased south-southeasterly swell around 7-8 seconds. Given the increased swell, there is a MODERATE risk for the development of dangerous and life threatening rip currents at the Jersey Shore. There is a LOW risk at Delaware beaches where it currently appears the increased swell will not have as much influence.

Monday, northwest winds in the morning of 10-15 mph, becoming east- southeasterly in the afternoon around 10 mph. Breaking wave heights will be 2-3 feet. There will be a light east- northeasterly swell increasing some in the afternoon around 6-7 seconds. Given the orientation of the winds and swell, there is a MODERATE risk for the development of dangerous and life threatening rip currents at Jersey Shore beaches with the exception of those off of Cape May County, and a LOW risk for beaches off Cape May County and all Delaware beaches.

Ocean water temperatures are generally near 60 degrees for much of the Jersey Shore and the low 60s for Delaware beaches. These chilly water temperatures can quickly cause hypothermia and physical incapacitation to anyone suddenly immersed in the water.

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

PHI WATCHES/WARNINGS/ADVISORIES

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