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
188 FXUS61 KAKQ 141127 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 727 AM EDT Sun Jul 14 2024 .SYNOPSIS... A weak frontal boundary will wash out across the area this morning. Isolated to widely scattered showers and storms are possible today, followed by a mainly dry and hot pattern Monday through most of Wednesday. An unsettled period returns late Wednesday through Saturday, as a cold front stalls across the area. && .NEAR TERM /THROUGH TONIGHT/... As of 700 AM EDT Sunday... Key Message: - Humid today with isolated to widely scattered showers and storms this aftn. A very weak boundary remains over the region, but the isolated showers have dissipated. Marine fog/stratus continues across the lower MD and VA ern shore, as well as portions of interior NE NC and far SE VA. An SPS for this for widespread VSBYs of 1/2 to 1SM continue for another hour. The boundary will continue to weaken/wash out later this morning. The heat begins to build today, with dew pts in the mid to upper 70s across the SE, and in the upper 60s to lower 70s W of I-95 this aftn. Have issued a Heat Advisory for interior NE NC for heat indices making it to at or just above 105F. Elsewhere, heat indices will avg 100-104F this aftn. The flow aloft is zonal/westerly but with some weak shortwave energy forecast to move through later today. Will maintain 20-30% PoPs (highest interior NE NC), for some widely scattered aftn storms. An isolated strong storm with gusty winds is possible if they can organize to some extent given modest flow of 20-25kt in the 700-500mb layer. Any storms will dissipate after sunset, then warm and humid with lows mainly in the low-mid 70s. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... As of 345 AM EDT Sunday... Key messages: - Hot Mon-Tue with high humidity closer to the coast and slightly lower humidity well inland (Tue probably the hottest day). At least Heat Advisories likely, with Excessive Heat Warnings possible E of I-95. - Remaining hot Wednesday and humid area-wide but with a higher coverage of storms by afternoon (heat headlines possible but more uncertain) The heat really starts to ramp up again for Mon and Tue, as a broad upper ridge expands east from the desert SW to the SE CONUS. With the consensus being for 850mb temperatures rising to 20-22C Mon aftn, highs should easily climb into the mid 90s at the coast, with upper 90s/near 100F inland. The models all do show some degree of dew pts dropping into the upper 60s/near 70F in the aftn across inland areas where the highest temps are expected. Closer to the coast, dew pts likely stay in the mid 70s through the aftn, leading to peak heat indices 105-110F east of I-95, with 100-105F in the Piedmont. At least a Heat Advisory is likely for the east and possible for the west. Other than a stray PM tstm moving east off the Blue Ridge into the eastern Piedmont or a seabreeze tstm developing over NE NC, will keep remaining areas dry on Mon. Warm/muggy Mon night with lows ranging through the 70s. Likely a degree or two hotter on Tue across the region with highs in the mid/upper 90s to around 100F. At least a Heat Advisory will likely be needed for the entire area, with an Excessive Heat Warning possible in some locations. The models remain in decent agreement that Wed will be the last day of hot conditions as the upper ridge eventually breaks down, as strong upper trough translates SE from north central to the Great Lakes. Dew pts will be slightly higher on Wed than Tue (in the lower to mid 70s inland with mid to upper 70s SE), due to moisture pooling along a pre- frontal trough. Highs will be a few degrees cooler Wed (mid-upper 90s) but the higher dew pts may lead to similar heat indices with 110F+ possible in the E and SE. Isolated storms will be possible by early aftn, with scattered storms developing by mid aftn and beyond. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... As of 415 AM EDT Sunday... Key Messages: - A cold front moves in from the NW late Wed/Wed night, slowly moving through much of the area Thu, then stalling near or just south of the area Fri/Sat. The latest models remain in fairly good agreement that the upper level trough pushes from the Great Lakes to New England Wed night through Thu, but flattens out to the south as it approaches the strong/persistent upper level ridge anchored well offshore of the SE US coast. The consensus is for the upper ridge to retrograde west and become centered closer to the SE US coast into next weekend. Will have the highest chances for showers/storms across the NE Wed night, with all zones getting likely PoPs (~60%) on Thursday as the front slowly pushes south towards NC. Locally heavy rainfall will certainly be possible during this timeframe. Highs Thu will mostly be highly dependent upon the timing of the front, for now expecting mid 80s to near 90F. Cooler, but still humid Fri- Sat with highs mostly in the low- mid 80s. Friday may see some drier air push into northern portions of the FA as broad sfc high pressure builds east from the Great Lakes. As the upper levels ridge moves closer to the SE coast Sat, the flow aloft increases from the SW and expect to see more humid air even into northern zones by that time. Given uncertainty as to the exact timing and placement regarding the front, went a little below NBM PoPs for Fri-Sat, 20-30% north to 40-50% south (which is still above climo for most of the area). && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... As of 715 AM EDT Saturday... Low stratus and fog to start the TAFs at SBY/ECG, mainly VFR elsewhere. Expect the fog/stratus to burn off fairly quickly by 13-14Z. SCT cumulus should develop this aftn. There is a slight chc (PoPs ~20%) of showers/tstms this aftn-evening at all of the terminals, but not enough confidence to include any mention in the TAFs. Less fog expected tonight/Monday morning with a bit more of a southerly low level flow. Outlook: VFR conditions expected Monday through Wednesday AM. Shower/tstm chances increase by late Wed/Thu with periodic flight restrictions expected ahead of an approaching cold front. && .MARINE... As of 355 AM EDT Sunday... Key Messages... - Generally quiet marine conditions through Tuesday with winds turning southerly and gradually increasing. - South winds gusting to 20 kt are possible Wed/Thu ahead of a cold front. - Moderate Rip Current Risk today for the northern beaches With the surface front/trough near the waters this morning, expect light winds (less than 10 kt) through the day. The winds will initially be northwesterly, then gradually turn NE and then SE. These light onshore winds may allow the dense fog to continue into the morning, although current web cams in Ocean City suggest more lower clouds vs. fog. As such, will leave the dense fog advisory in place with a 12z expiration for now, however it is possible that it will need to be extended later on this morning. Winds will transitioning from easterly to southerly overnight tonight into Monday as the lee side trough develops. As we move into early next week expect the winds over the coastal waters to gradually increase from 10 to 15 kt on Monday as high as 15 to 20 kt by Wednesday due to the tightening pressure gradient between the approaching cold front over the Ohio Valley, and the Bermuda High to the SE of the area. Winds will stay 10 to 15 kt in the Chesapeake Bay and Rivers Monday into Tuesday before increasing to 15 kt with a few gusts to 20 kt on Wednesday. The cold front ends up stalling out over the area on Thursday, but gets a secondary push southward by Friday. It is still uncertain if the front will clear the southern waters, however the consensus is that it will clear the northern waters allowing the winds to turn NW. Regardless of where the front ends up, expect diminishing winds starting Thursday night as the gradient relaxes across the area. Southeast swell of 3 to 4 ft continue to impact the coastal waters this morning, but expect the swell to diminish through the day. Meanwhile, the light winds should keep waves and bay/rivers at a foot or less. Southerly winds developing by Monday and slowly increasing through Wed will allow wind waves to gradually build with seas of 2 to 3 feet in the bay by Wednesday and 3 to 4 feet over the ocean. Due to the southeast swell at 3 to 4 feet, will continue with the moderate rip current risk for the northern beaches today. Waves drop to 2 to 3 feet for Monday and Tuesday so will go with low rip risk for early in the work week. && .CLIMATE... Record Highs and record high mins may be challenged Mon-Wed. - Record Highs: - Site: Mon 7/15 Tue 7/16 Wed 7/17 - RIC: 100 (1995) 101 (1980) 100 (1980) - ORF: 101 (1995) 102 (1879) 100 (1887) - SBY: 100 (1995) 99 (1915) 99 (2012) - ECG: 97 (1997) 98 (1995) 99 (1942) - Record High Mins: - Site: Mon 7/15 Tue 7/16 Wed 7/17 - RIC: 77 (1993) 77 (1983) 76 (2005) - ORF: 82 (1992) 80 (1995) 80 (2021) - SBY: 79 (1995) 78 (2013) 80 (1983) - ECG: 78 (1993) 79 (2012) 80 (2019) && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...Heat Advisory from 11 AM this morning to 7 PM EDT this evening for NCZ013>015-030>032. VA...None. MARINE...Dense Fog Advisory until 10 AM EDT this morning for ANZ650-652. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB LONG TERM...LKB/TMG AVIATION...ERI/LKB MARINE...MRD CLIMATE...