textproduct: Wakefield

WHAT HAS CHANGED

A Marginal severe risk (level 1 out of 5) continues for Thursday and a Marginal risk for excessive rainfall has been added for Thursday as well.

KEY MESSAGES

1) A slow moving cold front will slowly drop through the region today. This will result in a localized risk for excessive rainfall and flash flooding. Additionally, a few strong to severe thunderstorms are possible across interior southern VA and NE NC.

2) Hotter temperatures return Thursday and Friday. Meanwhile, a more progressive upper level pattern develops Thursday and Friday. This will bring a series of upper level disturbances, which will have the potential to trigger strong to severe thunderstorms each afternoon and evening. There is also a risk for excessive rainfall and flash flooding across northern portions of the area Thursday.

3) Near-normal temperatures are expected this weekend into early next week, with additional chances for afternoon/evening thunderstorms Saturday, before trending drier later in the weekend into early next week.

DISCUSSION

As of 345 AM EDT Wednesday...

KEY MESSAGE 1...A slow moving cold front will slowly drop through the region today. This will result in a localized risk for excessive rainfall and flash flooding. Additionally, a few strong to severe thunderstorms are possible across interior southern VA and NE NC.

An upper level trough is located in vicinity of the New England coast early this morning. Meanwhile, a shortwave feature is tracking across the Mid-Atlantic coast on the southern periphery of the upper trough. At the surface, a stationary to slow moving cold front lingers over southern VA and coastal NE NC. An area of low-level streamline convergence is located in vicinity of the Northern Neck, and this is coincident with an axis of PW values of 2.3-2.4" and modest surface based instability. An area of slow moving to nearly stationary heavy rain and embedded tstms has lingered over the Northern Neck and there have been some reports of flooding early this morning. The latest trends from the HRRR depict that this area of streamline convergence lingers in vicinity of the western shore of the Ches. Bay through the morning. Therefore, some localized flooding from excessive rainfall will be possible, but also highly localized, and could creep into Hampton Roads.

Otherwise, the best chances of showers and aftn tstms gradually shifts to the SW today as the cold front moves through the region. Coverage of showers/tstms will be less today compared to the prior two days. Hence the flash flood threat will be more limited and localized this afternoon. A few stronger tstm cores are possible, and this could produce some localized damaging wind gusts across interior southern VA and NE NC. Not as hot today with high temperatures ranging from the upper 70s/around 80F at the coast, to the mid 80s inland.

KEY MESSAGE 2...Hotter temperatures return Thursday and Friday. Meanwhile, a more progressive upper level pattern develops Thursday and Friday. This will bring a series of upper level disturbances, which will have the potential to trigger strong to severe thunderstorms each afternoon and evening. There is also a risk for excessive rainfall and flash flooding across northern portions of the area Thursday.

The mid/upper level flow becomes more progressive Thursday and Friday. The 500mb flow increases to 30-35kt Thursday afternoon ahead of a subtle shortwave trough, with similar values Friday ahead of a more potent shortwave trough. With strengthening mid level flow and strong surface heating strong to locally severe tstms are possible each afternoon. The question on Friday is coverage given more drier downslope flow. Additionally, the 00z/08 HREF has a decent signal for heavy rain from NE of the RIC metro to the lower MD Eastern Shore (and points N). High temperatures reach the upper 80s to mid 90s each day. Dewpoints should drop enough each afternoon to keep heat indices in the upper 90s to lower 100s, but readings up to ~105F are possible in NE NC (especially along the northern shore of the Albemarle Sound).

KEY MESSAGE 3...Near-normal temperatures are expected this weekend into early next week, with additional chances for afternoon/evening thunderstorms Saturday, before trending drier later in the weekend into early next week.

Chances of afternoon/evening showers/tstms continues Saturday as a cold front slowly sags through the region. Otherwise, trending drier Sunday into early next week as high pressure returns in the wake of the cold front. Seasonally hot and humid Saturday, with high temperatures in the upper 80s to lower 90s. High temperatures trend down into the 80s Sunday and Monday, before a warming trend commences Tuesday into the middle of next week.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

As of 700 AM EDT Wednesday...

A weak cold front was slowly pushing S across southern VA as of 11z. IFR/LIFR conditions prevailed at ORF, PHF, and ECG, with MVFR at RIC and VFR at SBY. Brief IFR cigs are possible at RIC through 14-15z, with occasional MVFR cigs at SBY. IFR/LIFR cigs at PHF and ORF should gradually lift to MVFR by 14-15z and 15-16z at ECG. Scattered showers in vicinity of PHF and ORF have the potential to produce brief vsby restrictions in heavy rain through ~15z. Otherwise, isolated to scattered showers linger through this morning, with a few tstms possible by early aftn. However, the best chances move W of a line from RIC to ECG by later in the aftn. The wind will generally be E/ENE 5-10kt through the day, before shifting to ESE later in the aftn and evening. Additional IFR/MVFR stratus potentially develops late tonight into Thursday morning.

Outlook: Chances of aftn/evening showers/tstms return Thursday, with the probability 20% or less by Friday (better chances N/NW of an RIC-SBY line), then 40-60% by Saturday, and less than 30% Sunday.

MARINE

As of 345 AM EDT Wednesday...

Key Messages:

- Sub-SCA marine conditions are expected this week. NE 10-15 kt winds are expected through most of today.

- The risk of thunderstorms is lower today but increases again Thursday and Friday.

Generally benign marine conditions prevail through the forecast period. Winds this morning are E-NE 10-15 kt on the north side of a slow moving backdoor cold front. Similar winds continue through today, diminishing slightly and turning to the S-SE this evening into tonight as the front lifts back N. Seas will generally be around 3 ft during this time and around 4 ft 20+ nm offshore. S-SW sub-SCA flow is expected Thursday and Friday with 2-3 ft seas. Another front is forecast to cross the waters Saturday. Winds swing around to the N/NW Saturday and then NE Sunday.

While daily chances for storms are anticipated through the week, the chance today is comparatively lower than the past few days. Still, showers this morning could pose an isolated waterspout threat in the western Chesapeake Bay. Chances for more widespread storms, some strong to severe, increase Thursday and Friday. SMWs will be issued as necessary.

A moderate rip current risk is forecast today due to nearshore 3 ft waves and choppy surf. A low risk returns for the rest of the week.

EQUIPMENT

Repairs have been completed in the KAKQ radar and it is currently in service. However, some additional downtime will be needed today for some additional calibration.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...None.