Area Forecast Discussion
Issued by NWS Wakefield, VA
Issued by NWS Wakefield, VA
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323 FXUS61 KAKQ 301830 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 230 PM EDT Sun Jun 30 2024 .SYNOPSIS... Heat and humidity persist today, with strong to severe storms and locally heavy rain possible this afternoon into tonight. The front pushes south of the area Monday morning, bringing cooler temperatures and lower humidity Monday and Tuesday. Heat and humidity return later in the week. && .NEAR TERM /THROUGH TONIGHT/... As of 400 AM EDT Sunday... Key messages: - A Heat Advisory remains in effect for portions of the area this aftn for widespread heat indices 105-109F. - The potential is there for strong to severe storms this aftn/early evening, likely transitioning more to a heavy rain threat tonight. The latest WX analysis indicates a broad positively tilted mid/upper level trough extending from northern Quebec SW to the upper Great Lakes region. At the sfc, low pressure is moving through Quebec, with a trailing cold front extending SW to the west slope of the Appalachians. As expected, hot and very humid conditions prevail as of midday with heat indices at or above 105F across most of central/southern VA and NE NC (temperatures mainly in low-mid 70s with dew pts in the mid to upper 70s). While some places may briefly reach into 110+ heat indices, the expected fairly widespread convection over the next 1-3 hrs should then lower the heat impacts considerably going into the late aftn and we may be able to cancel the Heat Advisory early in some areas. SPC nudged the Slight Risk slightly south to now cover the entire CWA. Lapse rates aloft (700-500mb) are rather weak, in the 5 to 5.5C/KM range so the hail threat this aftn will be minimal (mainly confined to MD where the lapse rates are slightly better). Overall, the severe threat this aftn/early evening will be from damaging wind gusts, primarily in the form of wet microbursts given the high humidity and PWATs analyzed at 2"+ over the entire CWA (highest in a SW to NE corridor through the heart of the CWA at ~2.20". Sfc-based CAPE is analyzed at ~4500 J/Kg with ML CAPE ~3000 J/Kg across interior eastern NC up into SE VA. With heights aloft not particularly high, the CAP will be weak and we should start to see showers and storms that have developed over central NC spread NE through 2pm/18Z. The latest 12Z runs from the HREF suggest the greatest threat for heavy rain to be over east and SE VA, peaking between 21-00Z. Given antecedent drought conditions, no Flood Watches will be issued, but any storms that become widespread and train through urban areas will need to be monitored for FFW issuances. Precip will taper off from NW to SE from late tonight through Mon morning. Lows tonight will range from the upper 50s/around 60 over the far NW, to the lower 70s far SE. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... As of 400 AM EDT Sunday... Pcpn will push SE of NE NC by Mon aftn, with N winds ushering much drier and cooler air into the region during the day. The sky will become mostly sunny (with lingering clouds over the SE) with highs in the upper 70s to lower 80s. Clear or mostly clear and comfortable Mon night, as sfc high pressure builds in from the N. Lows will be mainly in the upper 50s to mid 60s. The center of the sfc high will move to the srn New England coast during Tue. Generally mostly sunny and still rather comfortable with highs in the upper 70s to lower 80s at the coast, and in the mid 80s inland/Piedmont. The sfc high will sit just off the New England coast for Tue night. Clear to partly cloudy and still rather comfortable with lows in the upper 50s to upper 60s. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... As of 405 AM EDT Sunday... - Key Message: Heat and humidity returns later in the week. The models show good consensus for the return of the upper ridge over the southeast CONUS by mid to late next week. With sfc high pressure still centered just off the coast Wed, conditions will be seasonable for early July, with highs in the mid 80s to around 90, with moderate humidity levels and little to no chance for rain. Thu-Sat looks to turn hot with fairly high humidity. Highs will be mostly in the mid to upper 90s (lower 90s over the Lower MD and VA ern shore). With dewpoints climbing back into the lower to mid 70s, heat indices will likely be 100-105F. There also will be a chance for mainly aftn/evening tstms Thu-Sat. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... As of 1230 PM EDT Sunday... VFR conditions were prevailing at the TAF sites as of midday with SSW winds 5-10 kt. Sctd to numerous showers/tstms are likely this aftn through late this evening, with showers and a few tstms likely tonight into early Mon morning. Some of the storms could be strong to severe (esply during this aftn/evening), with brief wind gusts of 30-50 kt possible. Any tstm will be capable of producing brief IFR- LIFR flight restrictions in heavy rain. Winds shift to the NNE Mon morning and will be gusty, esply at the coast. High pressure and drier conditions return for later Mon morning/early Mon aftn through Tue, and mainly dry Wed. && .MARINE... As of 230 PM EDT Sunday... Key messages: - A Moderate Rip Current Risk for all area beaches through Monday. - A period of SCA conditions is expected for the bay, lower James and Currituck sound late tonight into Monday with northerly winds behind a cold front. SCAs have also been added to the southern coastal waters for late tonight into early Monday. - High pressure builds from the northwest for the midweek period, with more benign marine conditions Tuesday through midweek. Latest sfc analysis indicates a cold front to the NW of local waters, and its associated low pressure just to the NW of Maine. Ahead of the front, some scattered thunderstorms have formed, which may lead to brief gusts in excess of 40kt, heavy rain, and frequent lightning. Additional storms are expected later tonight as the front passes through the region. Latest wind obs show a S/SW wind of 10-15kt with a few gusts approaching 20kt. Seas are a bit slower to come up than forecast with buoy obs showing 2-3ft. Waves are 1-2ft this afternoon. The previously referenced cold front, a strong cold front relative to late June/July, crosses into the area after midnight late tonight/early Monday, with a decent CAA surge post-frontal. NNW winds of 15-25kt expected. Seas build to 3-5ft, with 2-4ft waves in the Ches. Bay. SCAs have been hoisted for the Ches. Bay, lower James, and Currituck Sound. Went ahead and raised SCAs for coastal waters S of Cape Charles due to a window for 25-30kt gusts in the few hours on either side of sunrise Monday. Winds remain N ~15-20 kt into Monday aftn, before diminishing to NE 10-15kt Monday night into Tuesday as high pressure builds SE toward the New England coast. Some gusts to ~20 kt will be possible in the lower bay and lower James Monday night before gradually diminishing. Seas slowly subside to ~3ft by late Monday night, as high pressure builds into the region. The high eventually settles S off the coastal Carolinas by midweek with the wind becoming southerly. Rip Currents: A moderate rip current risk is forecast for all beaches for the rest of today and Monday. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...Heat Advisory until 6 PM EDT this evening for NCZ012>017- 030>032. VA...Heat Advisory until 6 PM EDT this evening for VAZ065>069- 079>090-092-093-095>098-512>520-522>525. MARINE...Small Craft Advisory from 10 PM this evening to 4 PM EDT Monday for ANZ630-631. Small Craft Advisory from 4 AM to 4 PM EDT Monday for ANZ632>634. Small Craft Advisory from 4 AM to 1 PM EDT Monday for ANZ638. Small Craft Advisory from 4 AM to 10 AM EDT Monday for ANZ656- 658. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB/TMG LONG TERM...LKB/TMG AVIATION...LKB/TMG MARINE...AM/MAM