textproduct: Wakefield

WHAT HAS CHANGED

Updated full discussion. No major forecast changes.

KEY MESSAGES

1) A more typical summertime pattern takes hold today and continues through the rest of the workweek. Afternoon/evening thunderstorm chances return on Friday.

2) Shower and thunderstorm chances continue through the weekend with hot and humid weather expected, especially on Saturday. Dry weather and slightly cooler temperatures return early next week.

3) A warming trend is expected by the middle of next week, but shower/storm chances remain very low through Wednesday.

DISCUSSION

As of 235 AM EDT Thursday...

KEY MESSAGE 1...A more typical summertime pattern takes hold today and continues through the rest of the workweek. Afternoon/evening thunderstorm chances return on Friday.

Very pleasant wx continues early this morning with temperatures generally in the 60s-lower 70s and dew pts in the upper 50s-lower 60s. Surface high pressure has pushed just to our SE, with very light S-SE flow across the area. Quasi-zonal flow prevails aloft from the central CONUS to the Mid-Atlantic, with several shortwaves tracking from the High Plains to TN Valley.

A warming trend begins today with upper 80s expected across the majority of the area (lower to mid 80s at the coast) along with increasing humidity, but still somewhat comfortable for late June. Dry weather will continue to prevail through Friday morning. It will be even warmer (low-mid 90s) on Friday with continued low-level S-SW flow. Heat indices ~100F are possible in SE VA/NE NC, but generally mid/upper 90s for most of the area. However, an approaching shortwave will bring a chance of showers and tstms to the area during the afternoon and evening. While it is uncertain exactly how convection will evolve, there are hints that tstms initially develop in 2 areas Friday afternoon: along the higher terrain to our west and to our SW across the central Carolinas. The highest storm chances will initially be across northern and western portions of the area, with isolated-scattered convection potentially spreading E or SE during the early part of Friday night before diurnal weakening occurs. It is important to note that most areas probably stay dry Fri aftn/evening, especially in SE VA/NE NC. With the heat and humidity, a few stronger tstms capable of producing highly localized damaging wind gusts cannot be ruled out, especially given increasing 500mb flow in advance of a shortwave trough to our NW.

KEY MESSAGE 2...Shower and thunderstorm chances continue through the weekend with hot and humid weather expected, especially on Saturday. Dry weather and slightly cooler temperatures return early next week.

The upper level flow gradually shifts from the W to NW over the weekend as strong ridging builds over the Mississippi River Valley. A series of shortwaves will drag a cold front through the area late Sunday or Sunday night. While there could be an isolated shower or storm closer to the coast Saturday morning-midday, scattered to potentially numerous showers/tstms are expected area-wide from Saturday afternoon through Saturday evening as a slightly stronger shortwave tracks over the area. With decent W-WNW flow aloft, some storm organization will likely occur on Saturday. Convective coverage likely peaks during the 4 PM-9 PM timeframe before gradually weakening Saturday night. Once again, a few stronger tstms will be capable of producing highly localized damaging wind gusts as it will continue to be hot and humid. In fact, 100-105F heat indices are forecast across southern VA/NE NC. Convective coverage is expected to be a bit less on Sunday and confined more to southern portions of the FA as the front begins moving through the area and the low-level flow becomes N-NE across northern portions of the FA. Dry and fairly pleasant weather for the end of June is expected on Monday, with temps in the mid-upper 80s and noticeably lower humidity as high pressure builds toward the area from the NNE.

KEY MESSAGE 3...A warming trend is expected by the middle of next week, but shower/storm chances remain very low through Wednesday.

Upper heights gradually rise from Tuesday-Wednesday as the strong ridge builds E from the Mississippi River Valley. This will lead to a warming trend, though storm chances will remain very low with sfc high pressure remaining just offshore and no forcing mechanism for convection. After seasonable temps Tuesday, temps could rise well into the 90s by the middle to latter portion of next week with heat indices climbing above 100F across a decent portion of the area.

AVIATION /12Z THURSDAY THROUGH MONDAY/

As of 640 AM EDT Thursday...

VFR conditions prevail through the 12z TAF period. Light and variable winds tonight become SW 5-10 kt by mid to late morning. Sea breeze effects will favor SE winds for the coastal terminals in the afternoon. Scattered CU can be expected during the late morning and afternoon hours. VFR tonight with light S-SE winds.

Outlook: Primarily VFR conditions through midday Fri. Diurnally driven showers and thunderstorms develop Friday afternoon and evening, with the best chc at RIC/SBY. There is a better chc of showers/tstms on Saturday across the entire area, and low-end shower/storm chances continue on Sunday (mainly S/SE). Prevailing conditions will be VFR outside of sub-VFR conditions in convection. VFR conditions are expected to return by the beginning of next week as a cold front moves south of the forecast area.

MARINE

As of 235 AM EDT Thursday...

Key Messages:

- South to southeast winds in the Chesapeake Bay increase around Small Craft Advisory criteria this afternoon into late tonight.

- Generally quiet marine conditions expected for the weekend outside of any thunderstorm activity ahead of a cold front on Friday through Saturday night.

High pressure has shifted offshore this morning and winds have shifted to the southeast to south. Current marine observation sites are measuring between 5-10 kts along the rivers and 10-15 kts across the Bay and coastal waters. Seas have quickly subsided since yesterday morning, 1 ft or less in the Bay and 2-3 ft in the coastal waters.

The pressure gradient will increase across the waters today, and the channeling up the Chesapeake Bay may allow for 15-20 kt winds this afternoon into tonight has prompted the issuance of a brief Small Craft Advisory. While it will be very marginal, will likely see a few hours SCA winds/gusts in the Bay. South winds of 10 to 20 kt will continue into Friday although the strongest winds may be in the coastal waters. Winds turn southwest ahead of a cold front which passes through the waters Saturday night leading to winds turning north and northeast by Sunday. However, the expectation is that winds will stay less than 15 kt through the weekend outside of any thunderstorm activity which may occur on Friday and Saturday. Seas throughout the weekend generally 1 ft or less in the Bay and 3 feet or less over the coastal waters.

A low rip current risk will likely remain through late week with generally benign conditions currently forecast, the lack of shore- normal flow, and shorter period waves.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 4 PM this afternoon to 4 AM EDT Friday for ANZ630>632-634.