Marine Weather and Tide Forecast for Gloucester Point, VA

NEAR TERM /UNTIL 6 AM TUESDAY MORNING/
As of 259 PM EDT Monday...

Key Messages:

- Flood Watch in effect through late tonight for most of our VA counties just inland of the Chesapeake Bay, and has been expanded to include Dorchester and Wicomico in MD.

- Gusty winds and heavy rainfall will accompany the convection this evening and tonight.

Convection has developed along a sea breeze boundary in Hampton Roads area, and has remained relatively stationary, prompting the issuance of a Flash Flood Warnings for portions of Norfolk and VA Beach. Otherwise, it has remained mostly quiet across the remainder of the local area aside from the occasional pop-up sea breeze shower along the coast and Eastern Shore. GOES Visible imagery is highlighting a widespread cumulus field across basically the entirety of the forecast area. Local radars are detecting a line of storm to the west of our area that are slowly approaching our piedmont counties.

This afternoon's setup is featuring a similar environment to the past few days with ample instability, minimal inhibition, and anomalously high PW values. Shear will continue to be a limiting factor. With the steering flow being almost non-existent, the main threat will continue to be flash-flooding, though strong winds are possible from water-loaded downdrafts. The sea breeze convection will continue to push out outflow boundaries, so this could prolong convection in SE VA and NE NC for a few hours. A weak shortwave will move across the area just to our north this evening into tonight. As this is a transient feature, these storms will likely not be quite as stagnant as the ongoing daytime storms and be more linear/organized, but will still bring very heavy rainfall to the area that could produce additional flooding concerns. These slower moving storms, combined with PW values of 2"+, will lead to periods of heavy rainfall for localized areas across our forecast area this evening into tonight. With the antecedent rainfall we have seen over the past few days, flash-flood guidance continues to be lower, especially in more vulnerable areas such as the Richmond metro and adjacent areas, so it will not take much rainfall to lead to flooding. WPC has a majority of our forecast area in a Slight ERO today, and scattered instances of flash-flooding are possible. A Marginal ERO is in place across far SE VA and eastern North Carolina.

Convection will taper off from west to east overnight, but could be more prolonged than initially thought. CAMs have trended a little slower, so have extended the Flood Watch until 6 am to account for uncertainties in the timing. Overnight temperatures will drop into the lower to mid 70s. The development of patchy fog is again a possibility early tomorrow morning, and areas that receive rainfall this evening into tonight may see areas of dense fog closer to sunrise.

SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/
As of 259 PM EDT Monday...

Key Messages:

- Unsettled pattern continues into Tuesday and Wednesday with additional rounds of showers and storms as the front stalls NW of the area.

The front that is currently draped across the Ohio River Valley will likely inch a little closer to our area by Tuesday morning but is expected to stall to our northwest. This setup will bring yet another day of afternoon storms capable of gusty winds and heavy rainfall that could lead to flash-flooding. WPC continues to highlight our area with at least a Marginal ERO for now on Tuesday, though would not be surprised if this is upgraded to a Slight ERO due to the already saturated ground and the rainfall expected this evening increasing the vulnerability of areas to additional rainfall. A similar pattern continues into Wednesday with a bit more flow aloft possible during the afternoon and evening as a shortwave in the SW flow aloft potentially moves across the region. No real changes in the airmass through Wednesday with PWATs remaining around 2" so the threat for localized heavy rainfall and gusty winds persists. More cloud cover is expected with the front forecast to be a little closer to the area Tuesday and the possibility of the shortwave moving across the area Wednesday, so highs are forecast to only reach the upper 80s with temperatures nearing 90 degrees in the NE NC and SE VA.

LONG TERM /THURSDAY THROUGH MONDAY/
As of 259 PM EDT Monday...

Key Message:

- Heat and humidity build late in the week with Heat Advisories possible.

Looking ahead to late-week, upper ridging will build northwards into the area through the weekend. With this change in the pattern, convective coverage will likely diminish some, but due to the time of year and weaker ridge, have maintained scattered PoPs for the time being. With the decrease in cloud cover and storms expected combined with the upper ridging, temperatures will be able to climb into the lower 90s Thursday through Saturday, with Friday possibly seeing mid 90s across the area. At the same time, there will be an uptick in low level moisture and dew points will increase into the mid to upper 70s. Heat indices, especially on Friday, could eclipse 105F+ so Heat Advisories may be required. On Saturday, temperatures may not be quite as warm, so Heat Advisories may be necessary only in the southern portion of our area.

AVIATION /00Z TUESDAY THROUGH SATURDAY/
As of 815 PM EDT Monday...

Thunderstorms are becoming more numerous and forming a broken line to the NW of the main terminals, from northern VA back SW across the central VA piedmont. Earlier sea-breeze induced storms near the coast have diminished and radar trends suggest lower chances for showers and storms later tonight across SE VA and NE NC. Have maintained PROB30 groups for ORF/PHF, from ~03 to ~06Z (confidence being too low for TEMPO). The chances are greater at RIC/SBY and have added TEMPO groups for tstms from 01-04Z at RIC, and 02-05Z at SBY. Heavy rain will potentially reduce VSBYs to IFR-LIFR thresholds, and gusty winds will be possible (especially at SBY). After 06Z, the best chance for showers and tstms continuing will be at SBY, with more uncertainty elsewhere. With a more widespread cloud shield, SSW winds and some ongoing mixing, think the overall coverage of fog will be less than the past few nights at the main terminals, though there is still a chance for some low stratus and MVFR VSBYs, primarily from 09-14Z. Mainly VFR from late Tue morning through early-mid aftn, but with additional showers/tstms developing thereafter. After 18-19Z, have included PROB30 groups for tstms at all terminals except ECG.

Outlook: Additional scattered to numerous afternoon and evening thunderstorms are expected to recur Wed, along with the potential for early morning fog/stratus. Shower/storm coverage is forecast to be a bit lower late in the week.

MARINE
As of 259 PM EDT Monday...

Key Messages:

- Benign marine conditions continue through Wednesday outside of local influences from afternoon and evening thunderstorms.

- Small Craft Advisory conditions are possible Wednesday night into Thursday, mainly across the Chesapeake Bay and lower James River.

High pressure is building off the SE CONUS coast this afternoon, with 10-15kt SE winds over the waters and 1-2ft seas/waves. Expect a slight uptick in winds (to ~15kt) later this aftn/this evening with a few gusts to 20kt likely on the bay. Winds become S then SW tonight and diminish to 5-10kt. Similar conditions continue Tuesday with a mid-aftn to early evening sea-breeze influenced shift to SSE 10-15kt, before becoming SW ~10kt Tuesday night. The wind will mainly be SSW 10-15kt Wednesday with high pressure continuing to prevail offshore. Seas remain ~2ft Tuesday and build to 2-3ft Wednesday, with waves on the bay in the 1-2ft range. The pressure gradient tightens Wednesday night into Thursday as weak low pressure tracks well to our north. Confidence in a period of SCA conditions is increasing during this time, as local wind probabilities for 18kt+ winds have increased to 70-90% for a 6 hour period Wed night/Thu AM. Winds decrease over the open water during the day on Thu, but may become a bit gusty (to around 20kt) on the rivers/sound as mixing over adjacent land areas increases. The wind diminishes by Friday as the pressure gradient relaxes due to a weakening front dropping to the region. Seas build to 3-4ft (2-3ft nearshore) by Wednesday night and Thursday, with 2-3ft waves on the bay.

Isolated to scattered aftn/evening showers/tstms will continue much of the week. The main hazards with tstms will be brief strong wind gusts, frequent lighting, and reduced vsby in heavy rain.

AKQ WATCHES/WARNINGS/ADVISORIES
MD...Flood Watch until 6 AM EDT Tuesday for MDZ021-022.
NC...None.
VA...Flood Watch until 6 AM EDT Tuesday for VAZ048-060>062-064>069- 075>083-087-088-509>522.
MARINE...None.