textproduct: Wakefield

WHAT HAS CHANGED

Updated full discussion. No major forecast changes.

KEY MESSAGES

1) Low chances of afternoon and evening showers and thunderstorms return today with low to mid 90s expected.

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, with more significant heat possible by later in the week. Shower/thunderstorm chances remain very low through Wednesday.

DISCUSSION

As of 250 AM EDT Friday...

KEY MESSAGE 1...Low chances of afternoon and evening showers and thunderstorms return today with low to mid 90s expected.

High pressure is centered well offshore early this morning with zonal flow aloft from the central CONUS to Mid-Alantic. It is warmer than it has been the past two mornings with temperatures mainly in the lower 70s. Hotter and more summerlike (low-mid 90s) today with continued low-level S-SW flow. Heat indices ~100F are possible in NE NC, but generally mid/upper 90s for most of the area. An approaching shortwave will bring a low chc of showers and tstms during the afternoon and evening. The CAMs continue to hint that tstms initially develop in 2 areas this afternoon: along the higher terrain to our west and to our SW across the central Carolinas. Have more confidence in storms along the higher terrain given that is where the best height falls are, whereas there will be slight height rises across srn VA and NE NC later today. The best storm chances locally 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 tonight before diurnal weakening occurs. However, isolated showers and storms could persist through the night, though confidence in this is low. It is important to note that most areas probably stay dry today, 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. SPC has a Marginal Risk for severe storms (Level 1 out of 5) across northern portions of the FA.

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. 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 localized damaging wind gusts as it will continue to be hot and humid. The best chance for severe storms is along and south of I-64 where sfc heating/instability will likely be highest (temps rise into the lower 90s with lower 70s dew points). SPC has a Slight Risk for severe wx (Level 2 out of 5) across the southern half of the area, with a Marginal Risk north. The flash flood threat is rather low for most of the area Saturday, but there could be some hydro issues if convection coalesces over urban areas.

Even though there is a severe threat on Saturday, there is some uncertainty regarding exactly how much convection we see, as there will be low clouds around during the morning. Additionally, we will have to see if clouds or showers from decaying MCSs impact the area and inhibit sfc heating (and thus the amount of instability). If morning clouds and/or showers persist longer or are more widespread than expected, the severe threat Saturday aftn/evening would likely decrease. Convective coverage is expected to be a bit less on Sunday and confined more to southern and western 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, with more significant heat possible by later in the week. Shower/thunderstorm chances remain very low through Wednesday.

Upper heights gradually rise from Tuesday through late next week 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 from Mon-Wed due to sfc high pressure remaining just offshore and no forcing mechanism for convection. Isolated aftn/evening storms are possible on Thu/Fri, but confidence in any precip is low. After seasonable temps Tuesday, a pronounced warming trend is expected during the middle to latter portion of next week with temperatures above 100F possible from Wednesday-Friday (especially if the ridge builds farther east toward the central Appalachians like the 00z ECMWF/EPS shows). It appears as if there is a decent chance for 105F+ heat indices across a decent portion of the area by late next week as well.

AVIATION /09Z FRIDAY THROUGH TUESDAY/

As of 545 AM EDT Friday...

VFR prevails through the 12z TAF period, with S-SW winds of 5-10 kt. Mainly clear outside of high clouds this morning, but SCT CU with bases around 5 kft AGL is expected to develop this afternoon. Isolated showers or storms are possible area-wide this afternoon and evening but PoPs are too low to mention this in the TAFs attm. The highest storm chances will be to the NW of RIC and SBY. Isolated showers and storms may persist tonight, but confidence in precip is low. However, could see some MVFR to IFR CIGs late tonight into Sat AM as moisture increases ahead of the next system.

Outlook: 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 345 AM EDT Friday...

Key Messages:

- Sub-SCA marine conditions expected into early next week, outside of any thunderstorm activity late today and again Saturday ahead of a weakening cold front.

Latest analysis indicates surface high pressure centered well off the SE coast to Bermuda early this morning, with weak low pressure N of the local waters. Southerly winds remain a bit elevated, but gusts are only 20 kt at most so have allowed the SCAs in the Bay to expire. SSW winds will average 10-15 kt this morning, backing to the SSE late this aftn over the Bay. Waves will generally be 1-2 ft, with 2-3 ft seas on the Ocean. Winds then veer around to the SW on Saturday 10-15 kt ahead of a cold front that drops south across the waters Saturday night, turning winds to the NNE post- frontal Sunday into Sunday night. However, CAA continues to look minimal behind this front, and accordingly expect winds to remain below SCA thresholds at this time. Isolated thunderstorm activity is possible late this aftn into this evening, with more widespread showers and storms possible Saturday with the frontal passage. Any storms will likely require MWSs/SMWs issuances as needed.

A low rip current risk will likely remain through Saturday, with generally benign conditions currently forecast, the lack of shore-normal flow, and shorter period waves. With flow turning to a more shore-normal orientation Sunday, a Moderate Rip Current Risk has been maintained for Eastern Shore beaches Sunday, though this will depend on the timing of the increasing NE winds so confidence in this setup is not great at this point. Monday will have a higher probability for Moderate rips area- wide with 9-10 second periods and easterly onshore flow.

AKQ WATCHES/WARNINGS/ADVISORIES

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