Marine Weather and Tide Forecast for North Shore, VA

KEY MESSAGES
1) There is a marginal risk of excessive rainfall today/tonight.

2) Unsettled weather will persist through the rest of this week and into upcoming weekend with daily chances of showers and thunderstorms.

DISCUSSION
KEY MESSAGE 1...There is a marginal risk of excessive rainfall today/tonight.

A very moist airmass will remain in place today with PWATs ranging from 1.75" to 2.00". Surface front and associated upper level trough which helped focus the showers/storms the last couple of days/nights is now weakening with little in the way of dynamic forcing remaining. From this point forward shower activity will depend mainly on thermodynamic support with daytime heating contributing to the convective cycle today. CAMS suggest low level lift will be primarily orographic with afternoon deep convection firing along the ridgelines of both the Blue Ridge and the Highlands-Alleghany Mountains of WV. As such, think these will be the geographic areas to watch for the heaviest rain, but nothing organized enough to warrant a flood watch. Will continue to handle the localized frog stranglers with short fused flood advisories if needed. Unless there is storm cell training think any flash flooding would be localized due to the faster cell movement today...mean winds increasing.

Temperatures today should be similar to yesterday with highs in the 80s. It will remain muggy with dewpoints near 70. Wind flow this afternoon will be from the south, mean wind from south- north at about 14-18 mph, yesteday's easterly component no longer evident in any of the forecast soundings.

KEY MESSAGE 2...Unsettled weather will persist through the rest of the week and weekend with daily chances of showers and thunderstorms.

Forecast area will remain wedged between a large upper level ridge over Bermuda and an upper level trough to our northwest.
Wind flow between these two features will maintain a persistent flow of moisture into the forecast area, enough to fuel daily showers and thunderstorms, most of which should coincide with the peak heating of the day favoring the afternoon and evening hours. We are not expecting anything severe, but a marginal risk for flash flooding will continue to be a hazard due to the potential for high rain rates which may lead to runoff issues.

AVIATION /07Z WEDNESDAY THROUGH SUNDAY/
Moisture laden airmass is resulting bkn-ovc mvfr cigs with lcl ifr. Embedded within the cloud field are -SHRA with vsbys 2-5SM.

Daytime heating will result in higher cloud bases with mainly VFR cloud bases after 15Z/11AM. Daytime heating will also result in cloud buildups with scattered showers and thunderstorms during the afternoon and evening, bases 3-5kft, and vsby restriction confined to the shower activity. Winds today will remain light out of the south at under 10 kts. Wind gusts to 25 kts possible near storm cells.

Showers are expected to wane with loss of daytime heating, skies clearing followed by the development of patchy fog and local IFR vsby after midnight Wednesday night.

EXTENDED AVIATION OUTLOOK...

Forecast persistence through the end of the week and weekend with moist unstable airmass contributing to daily threat of showers and thunderstorms, mainly during the afternoon and evening hours. Overnight fog development also expected with greatest concentration within the mountain valleys.

HYDROLOGY
There is a marginal risk for excessive rainfall the next several days. Repeated chances of showers and thunderstorms amidst a moist air mass will persist the remainder of this week.
Not a lot of confidence in the details for any particular location.

PWAT values expected to remain in the 1.50" to 2.00" range. High ambient moisture will produce very efficient rainfall rates which could exceed 2-3 inches per hour. Urban areas and along mountainous terrain will be particularly susceptible to flash flooding.

Antecedent soil conditions are gradually turning wetter across the area, but there are still considerable rainfall deficits across the Piedmont.

RNK WATCHES/WARNINGS/ADVISORIES
VA...None.
NC...None.
WV...None.