Area Forecast Discussion
Issued by NWS Wakefield, VA
Issued by NWS Wakefield, VA
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
545 FXUS61 KAKQ 290735 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 335 AM EDT Sat Jun 29 2024 .SYNOPSIS... Heat and humidity return for today and Sunday. A cold front drops across the area late Sunday night through Monday morning. Ahead of it, strong to severe storms with heavy rainfall are expected. Dry weather is then expected through the middle of next week with additional heat concerns possible for Independence Day. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... As of 850 PM EDT Friday... High pressure is centered just off the New England coast this evening. Relatively comfortable outside at this hour with temps in the mid/upper 70s under moderate humidity levels (dew points in the 60s). A quiet evening/night is expected with mainly clear skies, at least initially. Cloud cover will build back in after midnight through sunrise as the low-level flow shifts to the SE and dew points creep up. An isolated shower or two is also possible in NE NC and SE VA after 06z/2 AM Saturday. Lows tonight will be in the upper 60s for much of the area with lower 70s in the SE and immediately along the bay. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... As of 355 PM EDT Friday... Key messages: - Hot and humid conditions return for the weekend, peaking on Sunday with dangerous heat indices around 105F. - A cold front brings potential for strong to severe storms and heavy rain on Sunday. Sfc high pressure to the NE slides farther offshore Saturday as low pressure moves into Eastern Canada with its trailing cold front gradually approaching Appalachia. A weak warm front will push north of the area, bringing southerly flow and hot temps. Should be mainly dry Sat, but may see isolated showers and thunderstorms across the area as weak shortwave energy passes through the area. CAMs do show some morning convection along the coast, so have introduced Schc PoPs in the SE. Highs will be in the low 90s. With dewpoints up into the low 70s, heat indices will be in the upper 90s to around 100. Sat night will not offer much relief from the heat with lows in the upper 70s. An upper trough and a strong cold front (for this time of year, at least) will approach the area Sunday, crossing the region Sun night into Monday. Ahead of the front, S/SW flow will allow hot and humid conditions to continue. Cloud cover and potential morning precip could hinder temperatures, but still expecting highs in the low-mid 90s. With dew pts in the mid 70s in most areas during peak heating, dangerous heat indices around 105F are in the forecast. Note that the dew point forecast continues to be a couple degrees lower than NBM and is more in line with MOS values. While the potential for morning convection exists, the main threat for scattered to numerous storms will be in the afternoon and into the overnight hours. Moderate to heavy rainfall is expected, especially for the SE half of the FA where PWs will approach 2.5". As such, WPC has placed this portion of the area in a Marginal ERO. Instability provided by the heat/humidity along with moderate shear will allow for some storms to be strong to severe, despite the stronger winds aloft being to the N. Thus, there is a slight risk for severe storms for much of the FA (~N of US460) and a Marginal elsewhere. Precip will clear out from NW to SE late Sunday night. Lows will be mid to upper 60s NW for most and the low 70s to the far SE. && .LONG TERM /MONDAY THROUGH FRIDAY/... As of 355 PM EDT Friday... Key Message: - A brief break in the heat is likely early next week before very hot weather potentially returns by Independence Day. High pressure fills in behind the front, bringing dry weather through mid week. Relatively cooler temps and much lower dewpoints will bring brief relief from the heat and humidity. Highs will be in the low to mid 80s. Warming some on Tuesday with highs in the mid 80s, but onshore flow keeps temps a few degrees cooler at the coast. Hot weather returns mid week with highs in the low 90s Wed and mid- upper 90s on the Fourth of July. With dewpoints creeping back toward 70 on Thursday, there is the potential for heat indices over 100. Remaining dry through at least Wed with a chc for afternoon thunderstorms on Thursday. . && .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... As of 235 AM EDT Saturday... High pressure centered off the New England was leading to light E/ESE flow at area terminals early this morning. As a result, stratus and lower SC were developing over portions of the region. Guidance continues to favor low-end MVFR, but cannot rule out patchy pockets of IFR stratus, esply in/near central VA (including RIC) until around 12Z this morning. Not expecting much in the way of VSBY restrictions. A few showers are also possible at ECG through this morning. For this aftn, mainly dry conditions expected though a very brief shower or storm is possible at any terminal. SCT CU again redevelops with a 7-12 kt S or SE wind. Mainly dry conditions continue into tonight, with just an isolated threat of a shower or storm. Sctd to numerous showers/tstms are likely Sun aftn through Sun night, some of which could be strong to severe. High pressure and drier conditions return for later Mon morning through Tue. && .MARINE... As of 335 AM EDT Friday... Key messages: - A High Rip Risk for eastern shore (VA/MD) beaches today, with moderate Rip Risk for SE VA & NE NC. Moderate Rip for all beaches Sunday. - Generally sub-SCA conditions with periods of breezy onshore/southerly winds today. A brief period of SCA level winds is expected in the bay late this afternoon and this evening, and a Small Craft Advisory is in effect during this period. - A period of SCA conditions is very likely for most of the waters on Monday with northerly winds behind a cold front. 1024+ mb sfc high pressure just offshore of the Delmarva remains in control of conditions across the region, with E-SE winds 10-15 kt this morning. Seas are 3-4 ft, with waves 1-2 ft. Have added a High Rip Risk for this morning for eastern shore beaches. E-NE swell 3-4 feet and 9 seconds persists this morning, and with the shore-normal component to wave energy, poses an elevated threat for rip currents, especially around low tide between 8-10 this morning. High pressure slides farther offshore today, allowing the front to the south to lift back north as a warm front. Resultant low-level flow turns around to the SSE this afternoon. As the NE swell weakens and SE winds and E-SE swell becomes more dominant this afternoon, it is possible that Rip Risk could ease a bit. For now though, High Rip Risk for northern beaches today, and a Moderate Rip Risk for SE VA/NE NC beaches. Moderate Rip Risk for all beaches Sunday. A Small Craft Advisory has also been issued for late this afternoon into the evening for the Ches Bay, with tightening pressure gradient allowing SSE winds to increase to ~15-20 kt. Local wind probs show a 40- 70% chc of sustained 18 kt winds between 6 PM Sat - 2 AM EDT Sun (highest in the mid/upper bay with some channeling effects). Winds become SSW and diminish to 10-15 kt after midnight tonight/early Sunday, with winds remaining SSW through Sunday afternoon. A decently strong summer cold front looks to approach the area Sunday before crossing the waters from NW-SE between 2-10 AM late Sunday night/early Monday morning. Scattered to numerous tstms are expected Sun aftn into Sun night, which will likely necessitate a few rounds of SMWs. Damaging winds will be the main threat, with a few of the storms capable of producing large hail and W-NW wind gusts to ~50 kt. Sub-SCA winds prevail outside of any storms from Sun- late Sun evening. However, there will be decent cool/dry advection following the cold FROPA Monday morning into early afternoon. N winds to increase to ~20 kt (with frequent gusts around or just above 25 kt). SCA probs are AOA 80% for most of the marine area late Sun night through midday Monday and another round of SCAs are likely be needed for all of the Ches Bay, Lower James, Sound and quite possibly for the upper rivers/coastal waters. Seas generally 3-4 ft this weekend with 1-3 ft waves. Seas could build to 5 ft S of Cape Charles on Monday following the cold FROPA (with 3-4 ft waves). Sub- SCA waves and seas are expected from Mon night through the middle of next week, as light return flow develops, with afternoon sea-breeze circulations likely prevailing for the mid week period. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 4 PM this afternoon to 1 AM EDT Sunday for ANZ630>632-634. && $$ SYNOPSIS...TMG NEAR TERM...AM/SW SHORT TERM...AM LONG TERM...AM AVIATION...TMG MARINE...ERI/MAM