Marine Weather and Tide Forecast for Williston, MD

NEAR TERM /THROUGH FRIDAY/
A seasonably cool and brisk early November day is ongoing as a secondary cold front tracks across the area this afternoon. Partly to mostly cloudy skies encompass much of the region outside of the Delmarva which is mostly sunny. Breezy northwest winds continue, occasionally gusting up to 25-35 mph. These winds will gradually diminish towards sunset.

Heading into tonight, the secondary front departs and high pressure over the Ohio Valley shifts over the Mid-Atlantic region. This will allow winds to further lessen, becoming light and variable to near calm overnight. Skies will mostly be partly cloudy, as some high clouds aloft stream into the region overnight. Depending on how much cloud cover moves in; will impact how far temperatures tumble. For now, expecting lows to range from the upper 20s to upper 30s for most. As a result, have maintained the Frost Advisories across extreme southeast PA, the Delmarva and southern NJ where the growing season remains active. Also, considered Freeze Warnings for our southern NJ counties, but due to the uncertainty to the extent of cloud cover limiting radiational cooling, held off on this for now.

For Friday, high pressure slides off the coast as our next system begins to approach from the west. An increase in high to mid level cloud cover will result as winds gain more of a southerly component with the high offshore. This will allow a subtle warm air advection regime to set-up with southerly flow gusting up to 30 mph in the afternoon. Highs as a result, are expected to top out in the upper 50s to mid 60s. Cannot rule out a stray shower making its way into the Poconos late in the day, but the bulk of precipitation should hold off until Friday night.

SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/
Friday night there will be a chance for rain moving into the region as a trough approaches from the west. Any rain amounts will be meager, so not expecting anything in the way of impacts.

Technically, it looks as if it will be a cold front, but the front will be weakening, and with winds shifting back to southerly pretty quickly on Saturday, highs on Saturday will actually be around 5 degrees warmer as compared to Friday.

Attention then turns to the surface low expected to develop in the Ohio Valley, The warm front with this low is expected to lift north through our area during the day time on Sunday. We have another chance for rain across the region as it does so. As with Friday night, rain amounts will be meager (greater than 70% chance across the region that rain amounts will be less than one half inch).

LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
Immediately on the heels of the warm front, the cold front associated with the low pressure system is expected to cross through the region, so chances for rain continue through Sunday night.

Monday into Tuesday, expecting much colder conditions. Highs on Monday could be 15 to 20 degrees lower than Sunday highs.
Higher terrain in the Southern Poconos may not even get to 40 for day time highs either Monday or Tuesday.

The upper level low is expected to be trailing behind the surface low. There is likely to be an area of precipitation near and just North of the center of the mid and upper level high.
However, there is a widespread in the models on where the center of that high will be - 500 mb low positions between various models at 12Z Mon range from Tennessee to Ontario! All that to say, the chance for seeing precipitation Monday into Monday night in our area is low (20%). However, if the center of the low is near and slightly south of our region, it could mean the first few flurries of the season on Monday night. Again though, the highest chance of this anywhere in our region is only 20%.

Slightly warmer pattern Wednesday into Thursday as the trough begins lifting out and flow turns more zonal. Highs back into the 50s.

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

Rest of Today...VFR with SCT/BKN ceilings around 6000 feet. Northwest winds around 10-20 kt with gusts up to 30 kt, diminishing through the afternoon. High confidence.

Tonight...VFR with some high clouds overnight. Northwest winds around 3-8 kt early, becoming LGT/VRB. Winds will then settle out of the south-southeast after 09Z. High confidence.

Friday...VFR with increasing clouds. South-southwest winds around 10- 15 kt with gusts up to 25-30 kt in the afternoon. High confidence.

Outlook...

Friday night.. MVFR or lower conditions possible with rain showers.

Saturday and Saturday night...VFR expected.

Sunday.. MVFR or lower conditions possible with rain showers.

Sunday night into Tuesday...Primarily VFR with NW and W winds gusting to 30 KT at times.

MARINE
As of 3 PM, the Small Craft Advisory on the Delaware Bay has been cancelled. A Small Craft Advisory remains in effect for the Atlantic Coastal Waters until 6 PM today.

Northwest winds around 15-20 kt with gusts up to 25 kt will continue to diminish this afternoon with seas around 3-5 feet. Tonight, northwest winds around 5-10 kt will shift to south-southwest after midnight with seas of 1-3 feet.

For Friday, light south-southwest winds in the morning will increase to 15-25 kt with gusts up to 30 kt in the afternoon. Seas of 2-4 feet early, build up to 8 feet in the afternoon. Further SCA's will be needed on all waters for Friday afternoon, but will hold off on issuance until the current SCA's expire.

Outlook...

Friday night and Saturday...winds and seas should slowly subside below SCA conditions by late Saturday.

Saturday night...No marine headlines expected.

Sunday...S winds once again increase near 25 KT.

Sunday night through Tuesday...An abrupt shift to NW and W winds is expected, with wind gusts likely to be able 25 KT for much of the period. There is a chance for gale gusts, especially Monday night and Tuesday.

FIRE WEATHER
A much cooler and rather dry airmass will filter into the region today behind a sequence of cold fronts. Minimum Relative Humidity values are anticipated to fall into the 30-40% range across much of the area this afternoon. Northwest winds will be gusty, especially through mid-day where winds may occasionally gust up to 30 mph. Winds will begin to diminish rather quickly in the afternoon, before relative humidities increase after sunset.

As a result, a Special Weather Statement has been issued for Delaware, the Eastern Shore of Maryland and eastern Pennsylvania through 6 PM today.

PHI WATCHES/WARNINGS/ADVISORIES
PA...Frost Advisory from 1 AM to 8 AM EST Friday for PAZ070-071.
NJ...Frost Advisory from 1 AM to 8 AM EST Friday for NJZ016>018- 021>023.
DE...Frost Advisory from 1 AM to 8 AM EST Friday for DEZ001>003.
MD...Frost Advisory from 1 AM to 8 AM EST Friday for MDZ012-015-019- 020.
MARINE...Small Craft Advisory until 6 PM EST this evening for ANZ450>455.