Marine Weather and Tide Forecast for Rehoboth Beach, DE

KEY MESSAGES
1) Showers and thunderstorms may continue to affect our southern most zones in Delmarva this evening but the threat for severe weather and significant flash flooding is low.

2) Fair and dry weather is expected for Thursday right through most of the weekend.

3) A pair of systems will bring more thunderstorm chances early next week.

DISCUSSION
KEY MESSAGE 1...Showers and thunderstorms may continue to affect our southern most zones in Delmarva this evening but the threat for severe weather and significant flash flooding is low.

As of early this evening, a cold front extends from near coastal Monmouth County south and west across south Jersey and then across central Delmarva. North of this boundary, low level cold air advection is underway with falling dew points. This is helping to stabilize things so no showers/storms are expected from this point forward for the majority of the area. South of the front it's still a bit more interesting as showers and storms are continuing to affect southern portions of eastern Maryland into Sussex County Delaware. Fortunately, recent radar trends show a weakening of these storms and the other good news is that these storms have been affecting areas just south of where the very heavy rainfall amounts occurred last night in northern Sussex County. That said, we'll still have to watch this area through at least this evening as front is slowing down as it pushes into this area with some weak impulses aloft moving through in the upper level flow. The severe weather threat appears low at this time with a somewhat greater potential though for localized flooding over portions of Sussex County DE. The front should finally be offshore bringing any showers/storms to an end by morning.

KEY MESSAGE 2...Fair and dry weather is expected for Thursday right through most of the weekend.

High pressure will build in for Thursday and continue to dominate the area through Saturday before starting to move offshore Sunday.
This will bring several days of sunshine, comfortable humidity levels, and temperatures a bit below average for this time of year.

KEY MESSAGE 3...A pair of systems will bring more thunderstorm chances early next week.

An open wave, mid level, short wave trough will be crossing through the Northeast on Sunday. Currently, we have relatively low chances for precipitation with this trough, primarily because there is limited opportunity for moisture advection before this trough arrives. Additionally, at this point there doesn't appear to be much in the way of boundary layer convergence.

There is a different story with the next mid/upper level trough approaching our region Tuesday into Wednesday. For this system, there will likely be ample opportunity for moisture advection Monday into Tuesday. Additionally, it is likely to be accompanied by a low and at least a cold front at the surface.
That being said, there is considerable differences between models on how this system will evolve. Some models are depicting this as an open wave, fast moving trough with only a limited opportunity for rain. Others, most notably the ECMWF, depict the mid upper level trough becoming a closed low, and then slowing its eastward progress considerably. Given the large differences in uncertainty, forecast stays close to the blend of guidance through this period.

AVIATION /00Z THURSDAY THROUGH MONDAY/
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Tonight...VFR expected at all TAF sites as storms are now expected to stay south of even MIV and ACY. Winds northwest this evening behind a cold front, before shifting to the north or north-northeast overnight with speeds around 5-10 knots or less. Moderate confidence.

Thursday...VFR conditions expected. North to northeast winds 5-10 knots, becoming light and variable Thursday night. High confidence.

Outlook...

Friday through Saturday...VFR.

Sunday...Mainly VFR.

MARINE
Seas will remain elevated on the Atlantic Ocean, so a Small Craft Advisory will remain through this evening.

Outlook...

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

Rip Currents...

For Thursday, winds will be out of the north and northeast 10-20 mph. Breaking waves are expected to be 2-4 feet with a 7 second period. With the onshore component of the wind and multiple swell groups expected, will maintain a MODERATE risk for the development of dangerous rip currents at all beaches.

For Friday, very similar conditions to Thursday are expected so we'll go with a MODERATE risk for the development of dangerous rip currents for all beaches once again.

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

PHI WATCHES/WARNINGS/ADVISORIES
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 2 AM EDT Thursday for ANZ450>455.