Marine Weather and Tide Forecast for Edgemere, MD

KEY MESSAGES
- 1) High pressure builds in through mid week.

- 2) Daily chances for showers and thunderstorms return Thursday, then continue Friday through Sunday.

DISCUSSION
KEY MESSAGE 1...High pressure builds in through mid week.

Late this morning, regional satellite and radar imagery showed an area of enhanced/textured cloudiness and isolated showers coming off the Blue Ridge into some the valleys of western and central VA. This appears to be tied to a weak mid-level impulse in the westerly flow aloft. Overall, the depth of moisture has diminished in the wake of last night's cold frontal passage, so as the aforementioned short-wave traverses the region into early afternoon, its main impact should be restricted to isolated/widely scattered showers and garden variety thunderstorms for portions of VA and far southern MD. Outside of that, we're looking at rain-free conditions for the balance of the day, with seasonable temperatures ranging from the 70s over the higher terrain of the Alleghenies, to the mid-upper 80s across the metroplex.

Surface high pressure will be the primary controlling factor, as it builds across the Mid-Atlantic into Wednesday, with dry conditions expected. A cold front will approach from the Great Lakes, bringing an increasing chance of showers and perhaps a thunderstorm by late Wednesday night.

KEY MESSAGE 2...Daily chances for showers and thunderstorms return Thursday, then continue Friday through Sunday.

Although timing remains a bit uncertain, a cold front looks to enter the area Thursday morning, then slowly cross through Thursday night. Questions regarding early day precip and cloud cover lend to uncertainty in how much instability builds Thursday afternoon, though a few stronger storms are certainly possible given increased flow aloft and lift along the front.

Model guidance is in relatively good agreement that the longwave pattern across the CONUS will amplify significantly heading into next weekend as unseasonably deep troughing digs across the Great Lakes and Ohio Valley. While there is some spread with respect to just how deep this trough will be and its exact east/west placement, nearly all solutions place us downstream of the trough, which will keep us in southwesterly flow aloft and keep the pattern active.
Daily chances for showers and thunderstorms are expected within the zone of large scale ascent downstream of the longwave trough sharpening to our west. Depending on how much instability develops, some of these storms could potentially be on the stronger side.
Temperatures are forecast to run slightly below normal, with highs in the upper 70s and low 80s, and overnight lows in the 60s.

Most solutions have the longwave trough making some eastward progress by Sunday night into Monday, which should result in a cold front passing through. Continued below normal temperatures and drier conditions are forecast behind the front for Monday.

AVIATION /13Z TUESDAY THROUGH SATURDAY/
NW flow as a cold front crosses along with some mid/high clouds will compete with high humidity for the formation of some fog through early this morning. The most likely TAF site to see fog seems to be KCHO where recent rain plus more displacement from the light NW flow associated with the approaching cold front is.

Otherwise, VFR conditions are expected at the TAF sites through mid week (Wednesday). Added a PROB30 for -SHRA at KCHO 18-22Z, though some TS or slightly later timing are possible. Rain may approach the TAF sites ahead of a cold front late Wednesday night, with TS possible Thursday afternoon and evening. Light N/NW flow is expected through tonight, becoming SW to S Wednesday into Wednesday night before possibly returning to NW Thursday into Thursday night depending on the placement of the next cold front.

Prevailing VFR conditions are expected for both Friday and Saturday, but showers or thunderstorms could lead to temporary restrictions either day. Winds will be light out of the northeast on Friday, before turning out of the southeast on Saturday. There is some uncertainty in the wind forecast depending on the placement of a nearby front and wave(s) of low pressure.

MARINE
Light winds are expected through the end of the week. Winds shift to then north/northwesterly today before returning to southerly by late Wednesday. A few enhancements are possible along the Chesapeake Bay during any of these wind shifts due to channeling, but prospects of advisory conditions are marginal at best. A pop up thunderstorm is possible mainly south of Annapolis and Dahlgren this afternoon or early evening. A cold front may bring additional thunderstorms Thursday into Friday.

Sub-SCA level winds are expected for both Friday and Saturday. Winds are forecast to be out of the northeast on Friday, before turning out of the southeast on Saturday. An afternoon thunderstorm can't be ruled out either day. There is some uncertainty in the wind forecast depending on the placement of a nearby front and wave(s) of low pressure.

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.