Marine Weather and Tide Forecast for Clarksville, VA

KEY MESSAGES
1) Scattered showers possible this afternoon. A Marginal Risk of severe storms remains in place for today, mainly for isolated severe storms late this afternoon/evening.

2) Mainly dry to end the week, with rain chances returning by Saturday, though drought conditions are also likely to persist.
Temperatures hover near or just below seasonal averages.

DISCUSSION
As of 315 PM EDT Wednesday...

KEY MESSAGE 1...Scattered showers possible this afternoon.
A Marginal Risk of Severe Storms remains in place for today, mainly for isolated severe storms late this afternoon/evening.

The latest wx analysis shows a warm front lifting northeast across the area with a weak cold front trailing behind. The warm front has begun to allow for some light precipitation across the piedmont and Eastern Shore. The latest hi-res model have consistently decreased the amount of pre-frontal showers across the area this afternoon.
Although minimal showers are expected, there have been virtually no breaks in the overcast skies today based on satellite imagery, which has keep destabilization to a minimum. The cold front will cross through the area this evening bringing a secondary chance of showers and storms. With the limited destabilization, will be hard to get strong to severe storms, although not impossible. SPC maintains a Marginal Risk of severe storms over the area for damaging winds, large hail, and an isolated tornado, but this is a very marginal Marginal Risk. Any rainfall received will likely average less than 0.10", but higher amounts in storms are possible.

KEY MESSAGE 2...Mainly dry to end the week, with rain chances returning by Saturday, though drought conditions are also likely to persist. Temperatures hover near or just below seasonal averages.

Still looking like a rather blocky pattern setup aloft for the late week into the weekend. The slow-moving low over eastern Canada drifts across northern New England, as a strong, but compact upper low pushes across the southern tier of CONUS, moving from Baja California Thursday to the Southern Plains and Mid-South by Friday and Fri night. The GFS Ensemble has trended toward the flatter/more suppressed and slower ECMWF solution, with the system moving across the Gulf coast, and the attendant surface low pushing along the Carolina coast Saturday, pushing some light rain into Hampton Roads and NE NC. In terms of sensible wx, it is looking more likely that the best rain chances and QPF remain to our south Saturday and Saturday night. The latest ensembles show the possibility of rainfall mainly across the southern half of the area on Saturday, with probabilities increasing from latest runs for 0.1" now showing 50-100% chance across the entire area and 40-70% chance of 0.5". The more rain the better, but still not looking like a drought buster.

AVIATION /19Z WEDNESDAY THROUGH MONDAY/
As of 150 PM EDT Wednesday ...

VFR conditions prevail at the start of the 18z/29 TAF period. A cold front approaches the area, expected to cross after 22z/6pm. A few light pre-frontal showers are possible this afternoon, but the latest hi-res guidance shows the showers decreasing in coverage as they move eastward, so have only included VCSH for RIC and SBY, where showers are more likely. Then with the front, isolated showers and storms are possible at all terminals.
Confidence in the convection reaching any given terminal is not high enough to have prevailing conditions, so have included TEMPOs for SBY/RIC/PHF and PROB30s for ECG/ORF. Mostly short lived flight restrictions are possible with the front. Winds will remain SE through this evening, becoming NE ~10 kt behind the front. A few gusts near 20 kt is possible.

Outlook: Conditions will return to VFR by THursday morning and lasting through Friday. Another storm system approaches the area on Saturday, bringing potential for additional flight restrictions Saturday into Sat night

MARINE
As of 315 PM EDT Wednesday...

Key Messages:

- A cold front approaches the region today and crosses the waters early Thursday with increasing SE winds ahead of the front and NW winds behind the front. Small Craft Advisories are in effect for the Chesapeake Bay.

- Coastal Flood Advisories are in effect tonight for the Chesapeake Bay side of the Maryland Eastern Shore and the southern shore of the tidal Potomac River.

High pressure remains offshore this aftn with low pressure and a cold front approaching from the W. The pressure gradient is expected to tighten later this aftn and evening with an increasing SSE wind, especially across the Ches. Bay later this aftn and evening. SCAs remain in effect for the Ches. Bay. 12z/29 model guidance has substantially lowered the strength of the CAA behind the cold front late tonight into early Thursday morning, with only marginal SCA conditions expected across the Chesapeake Bay. Given that SCA flags are in effect for the Ches. Bay, these have been extended through 10AM Thursday to account for the marginal NW surge. Seas should largely remain 3-4ft this aftn through Thursday morning, but could touch 5ft out near 20nm tonight. However, this is not enough to warrant SCAs for the coastal waters. Waves in the Ches. Bay are expected to build to 2-3ft, with 4-6ft seas in the 20-60nm offshore waters.

The latest guidance depicts a brief northerly surge Thursday night for the Ches. Bay. Additional SCA flags are possible, but this surge also looks marginal. Low pressure tracks off the Outer Banks Saturday. This has the potential to bring SCA conditions, especially for the lower Ches. Bay, lower James, and southern coastal waters with a NE to N wind and elevated seas.

Coastal Flooding
Tidal anomalies are expected to build to ~1.5ft above astronomical during high tide tonight, which is the higher astronomical high tide. This will potentially push sites along the Bay-side of the MD Eastern Shore and southern shore of the tidal Potomac into minor flood thresholds. Coastal Flood Advisories have been issued for these locations.

AKQ WATCHES/WARNINGS/ADVISORIES
MD...Coastal Flood Advisory from 10 PM this evening to 6 AM EDT Thursday for MDZ021>023.
NC...None.
VA...Coastal Flood Advisory from 11 PM this evening to 4 AM EDT Thursday for VAZ075-077.
MARINE...Small Craft Advisory until 10 AM EDT Thursday for ANZ630>632- 634.