textproduct: Wakefield

WHAT HAS CHANGED

SPC has introduced a Marginal Risk (level 1/5) for strong to severe storms across the northern half of the area today and tonight.

KEY MESSAGES

1) An unsettled pattern develops later today into the weekend, with daily chances for showers or thunderstorms.

2) Drier next week as an upper ridge builds into the region with above normal temperatures.

DISCUSSION

As of 255 AM EDT Thursday...

KEY MESSAGE 1: An unsettled pattern develops later today into the weekend, with daily chances for showers or thunderstorms.

Surface high pressure is now well offshore in the Atlantic with an upper trough and surface low across Quebec. The associated cold front extends from the low southwestward into the Ohio Valley. An upper ridge is noted across the central and eastern Gulf Coast, extending northeast into the local area.

The northern upper trough and associated surface low will slowly shift east-southeast today, gradually suppressing the ridge. The cold front approaches from the northwest this evening, slowing as the boundary aligns parallel to the mid-and upper-level quasi-zonal flow. Compressional heating ahead of the front will yield highs reaching the low-to-mid 90s inland from the immediate coast. Latest guidance has maintained the potential for isolated to widely scattered convection entering western areas late this afternoon, spreading across the Virginia Northern Neck and Maryland Lower Eastern Shore tonight into early Friday. While most of the stronger mid level flow will remain displaced north of the local area, 20-25 kt of deep layer shear will be in place late this afternoon into the evening hours. Combined with MLCAPE of 1000-1500 J/kg, a few stronger thunderstorm cores are possible across the northern half of the area with the potential for locally strong straight line winds. SPC has introduced a Marginal Risk (lvl 1/5) for strong to severe storms this afternoon and tonight, primarily for the northern half of the CWA.

00z models continue to slow the progression of the front across the region Friday. The 00z HREF shows a signal for locally heavy rainfall in areas that remain along and south of the stalled front, primarily NE portions of NC and along the VA/NC border counties farther west. High temps will vary considerably with low 80s N and low 90s S.

Better areawide storm chances arrive Saturday as the stalled front lifts back north and a few weak perturbations push across the region. Considerable cloud cover and scattered to numerous showers and storms, including the potential for some locally heavy downpours, will cap Saturday's highs in the low to mid 80s for most, with upper 80s limited to the southern third of the CWA. There remains an area wide ERO that would suggest some potential hydro issues in the typical spots for Saturday, given the moist, modestly unstable airmass and relatively weak steering flow.

The front washes out late weekend into early next week. Some additional showers and storms remain possible Sunday, though coverage will be noticeably lower than Saturday.

KEY MESSAGE 2: Drier next week as an upper ridge builds into the region with above normal temperatures.

Mostly sunny and dry conditions are expected on Monday with only a slight chance for a shower or two across NE NC in the late afternoon or early evening hours. Temperatures will be in the mid to upper 80s with a few spots across the south possibly touching 90 degrees. Continued dry Tuesday with upper 80s and low 90s in the forecast. Chances for showers and storms tick up mid to late week with temperatures continuing above seasonal norms as upper ridging across the Gulf Coast builds back toward the region.

AVIATION /06Z THURSDAY THROUGH MONDAY/

As of 140 AM EDT Thursday...

VFR conditions largely prevail through the 06z TAF period. Breezy SW winds ~10 kt overnight, increase to 10-15 kt today with some gusts 15-20 kt, especially near the coast. Mostly clear skies early this morning will become partly cloudy late morning through the afternoon. A front will approach the region from the NW this evening with some potential for showers and storms at RIC and SBY. Low confidence on coverage and timing limits mention to PROB30 groups. Brief reductions to MVFR or locally IFR conditions is possible in any convection that manages to impact the terminals late this afternoon into the evening.

Outlook: Additional precip is possible late tonight, still mainly at SBY and RIC. This will also bring the potential for continued short-lived MVFR CIGs across mainly northern terminals Thu night into Friday morning. The boundary slowly drops south through Friday morning, but lingers near the VA/NC border Friday afternoon through early Sunday, with daily chances of showers/storms (highest chances southeastern terminals and greatest on Saturday). MVFR (LCL IFR) CIGs will also be possible from PHF-ORF-ECG Friday night into Saturday morning, with additional opportunities of sub-VFR CIGs/VSBY in scattered to numerous convective showers and embedded t-storms Saturday afternoon and evening.

MARINE

As of 255 AM EDT Thursday...

Key Messages:

- Elevated SW winds continue early this morning. Small Craft Advisories remain in effect for the Chesapeake Bay, northern coastal waters, and tidal rivers.

- A period of generally benign marine conditions is favored from this weekend into early next week.

Latest analysis depicted high pressure offshore and a cold front well to the north, attached to a strong area of low pressure well to the north of the Great Lakes. WAA has ramped up ahead of the front given the pressure gradient between the low in Canada and the high offshore. SW winds were 20-25 kt with gusts up to 30 kt across the Ches Bay and northern coastal waters (north of the VA/NC border), 15- 20 kt with gusts up to 25 kt across the tidal rivers and NC coastal waters, and 10-15 kt with gusts up to 20 kt across the Currituck Sound. As such, SCAs remain in effect across the Ches Bay, coastal waters north of the VA/NC border, and tidal rivers this morning. SCAs end at 8 AM across the upper rivers, 10 AM across the Lower James, Ches Bay, and coastal waters between Cape Charles Light and the VA/NC border, and 1 PM across the northern coastal waters.

SW winds diminish later this morning into this afternoon to 10-15 kt with gusts up to 20 kt for most. However, CAMs continue to show light wind across the middle Ches Bay around 5-10 kt. As the cold front slowly moves south across the local waters tonight into early Fri morning, SW winds may briefly increase ahead of the front to 15- 20 kt across the lower Ches Bay and southern coastal waters. However, this surge looks to be brief with low confidence in SCA conditions across the lower Ches Bay and Currituck Sound. As such, will hold off on any additional SCAs (or extensions) at this time. Winds become NE 10-15 kt with gusts up to 20 kt behind the cold front Fri. While some CAMs show 15-20 kt winds behind the front, the CAA is weak with most guidance showing winds remaining below SCA. Nevertheless, will continue to monitor the potential for low-end SCAs behind the front. The flow becomes onshore Fri night into Sat with 10-15 kt winds possible Sat. Otherwise, a period of generally benign marine conditions is favored from this weekend into early next week.

Waves and seas of 3-4 ft and 4-6 ft respectively (3-4 ft seas across the NC coastal waters) subside to 1-2 ft and 2-4 ft respectively by this afternoon. Waves and seas then likely remain 1-2 ft and 2-3 ft respectively from late tonight into early next week. Otherwise, the rip current risk remains low today and tomorrow. However, 9-10 second periods across the southern beaches today may allow for a locally higher risk for a few rip currents. That being said, wind directions are unfavorable, so will keep a low rip current risk for now and reevaluate later in the morning depending on what lifeguard reports indicate. Additionally, with onshore flow Sat, a moderate rip current risk exists across the northern beaches.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 10 AM EDT this morning for ANZ630>632-634-639-656. Small Craft Advisory until 8 AM EDT this morning for ANZ635>637. Small Craft Advisory until 1 PM EDT this afternoon for ANZ650- 652-654.