Marine Weather and Tide Forecast for Henlopen Acres, DE

NEAR TERM /THROUGH FRIDAY/
A hot and oppressively humid day is ongoing with widespread heat indices of 100-105 being observed across most of the region. A Heat Advisory remains in effect through this evening.

Relief is on the way however in the form of a cold front marching across Pennsylvania at this hour. This front could also trigger a few showers and thunderstorms this afternoon and into the evening. However, the forcing isn't overtly strong, and while we have around 3500-4500 J/KG of CAPE, shear isn't anything to write home about, with effective bulk shear around 20-25 kt over our area. Mid-level lapse rates are quite meager as well, only around 6-6.5 C/Km. If something could get organized, a strong to severe thunderstorm can't be ruled out with the amount of moist and unstable air in place. Steep low- level lapse rates could also aid in stronger downdrafts.
Overall, the threat is rather marginal given the limiting factors in play, and a MARGINAL (1/5) risk is in place for the entire area. PoPs range from 20-40% along and west of the I-95 corridor and about 15-30% south and east. Main threat would be damaging wind gusts from about 4 PM to 9 or 10 PM.

The cold front should swing through tonight with skies clearing out some and humid air being swept out of the region. It starts to feel more comfortable tonight as dew points fall quickly in the wake of the front. Lows generally range from the upper 60s to low to mid 70s. Areas in the Poconos could even get down into the 50s.

While the cold front clears our area overnight, it will stall out just to our south and east. This could result in more clouds and a few showers/isolated thunderstorms across the Delmarva peninsula and far South Jersey, areas that are in closer proximity to the stalled boundary. Not expecting any severe or hydro threats however. Elsewhere, it will be a rather quiet day and much more comfortable than today as dew points will be in the low to mid 60s for most spots, and even potentially into the 50s north of I-78. Highs are more seasonable, or even a few degrees below normal for tomorrow-in the low to mid 80s.

SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/
An upper-low initially over portions of the Hudson Bay and northern Quebec will shift slowly southeastward through the period. With ridging centered over the southeastern US, our region will initially have weak zonal flow aloft and neutral heights. Friday night, an area of low pressure passing to the south could continue to bring lingering chances for showers across portions of the Delmarva, but high pressure over New England should keep most of the area dry. Friday night lows should generally be in the mid-upper 60s, with a few low 70s possible, outside of the Poconos where temperatures could fall into the upper 50s.

A subtle shortwave embedded in the zonal flow regime should pass through the area on Saturday. As the surface high shifts east off of the coast, shower and storm chances will increase across our entire area. As of right now, the greatest chance appears to be from Saturday afternoon into much of Saturday night. Instability looks to be quite limited with this system, so severe weather is not anticipated at this time. However, there will be enough moisture to work with to support at least some potential for excessive rainfall. As such, the Weather Prediction Center has introduced a Marginal Risk (1 of 4) across most of our area for flash flooding.

As the upper-low shifts southeast through the weekend, it should become more of an open trough with the axis pivoting through northern New England Sunday night. A surface cold front will approach the area from the northwest by Sunday evening.
Scattered showers and storms will be possible across much of the area during the afternoon and evening hours ahead of the front.
Models are hinting at some instability and wind shear that could lead to some severe potential, so this will need to be monitored in the coming days.

The cold front appears likely to bring in a much more pleasant airmass. While it may not drop temperatures too much, it should help with the high moisture content which has contributed to the oppressive nature of the recent heat.

LONG TERM /MONDAY THROUGH THURSDAY/
With high pressure over the area and the recent frontal passage having reduced both temperatures and dewpoints across the area, Monday and Tuesday should both be quite pleasant. Partly to mostly clear skies and fairly light winds are expected.
Afternoon highs look to be in the low-mid 80s both days, with overnight lows generally in the low 60s.

While no major storm systems are anticipated in the extended period, it may become slightly more unsettled Wednesday into Thursday, with at least low chances for afternoon storms returning. In addition, we will likely see temperatures start to warm again, with most locations seeing highs approaching 90 again by Thursday.

AVIATION /19Z THURSDAY THROUGH TUESDAY/
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Today...Primarily VFR, though brief restrictions possible as scattered to isolated showers and thunderstorms develop later this afternoon. Added VCTS groups to KRDG/KABE/KTTN for a few hours this afternoon, with lesser chances at other terminals, where thunder was left out of the TAFs. 30-40% chance of SHRA/TSRA at KRDG/KTTN/KABE and 15-25% elsewhere. Winds out of the southwest 10-15 kt gusting 20- 25 kt. Moderate confidence.

Tonight...VFR with decreasing clouds. Southwest winds gradually becoming northwest overnight around 5-10 kt following frontal passage. High confidence.

Friday...VFR. Northwest winds 5-10 kt. High confidence.

Outlook...

Friday night...VFR. No significant weather expected.

Saturday through Sunday...Sub-VFR conditions will be possible at times in scattered showers and storms.

Sunday night through Tuesday...VFR. No significant weather expected.

MARINE
No marine headlines in place through Friday. Winds out of the southwest through this evening before becoming northwesterly overnight. Wind speeds of around 10-20 kt. Seas 3 to 4 feet. A few thunderstorms possible, especially north of Little Egg Inlet, this evening.

Outlook...

No marine headlines anticipated. Winds are expected to remain below 25 kt with seas remaining below 5 ft. Scattered showers and storms will be possible Saturday and Sunday.

Rip Currents...

For today, southwest winds increase to 15-25 mph with breaking waves around 1-3 feet and a building southerly 3-4 foot swell around 6-7 seconds. As a result, have upgraded Cape May and Atlantic County beaches to MODERATE due to more perpendicular swell and have maintained a LOW risk for rip currents for the remainder of the Jersey Shore and Delaware Beaches.

For Friday, northwest winds around 5-10 mph with breaking waves around 1-2 feet and a southerly 2 foot swell around 6-7 seconds.
As a result, have maintained a LOW risk for rip currents at all beaches.

Rip currents occur often in the vicinities of jetties and piers and the speed of the currents are generally maximized at low tides.

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

PHI WATCHES/WARNINGS/ADVISORIES
PA...Heat Advisory until 8 PM EDT this evening for PAZ060>062-070- 071-101>106.
NJ...Heat Advisory until 8 PM EDT this evening for NJZ001-007>010- 012>027.
DE...Heat Advisory until 8 PM EDT this evening for DEZ001>004.
MD...Heat Advisory until 8 PM EDT this evening for MDZ012-015-019- 020.
MARINE...None.