textproduct: Wakefield

WHAT HAS CHANGED

Updated Aviation discussion and key messages.

Lowered high temperatures across the north tomorrow, but increased them across the south. Lowered temperatures a bit more for Friday and Saturday.

KEY MESSAGES

1) Another hot day ahead today, with Thursday also looking quite warm for the southern half of the area. A strong cold front brings the potential for strong to severe storms to northern portions of the area late this evening.

2) An increasingly unsettled pattern takes shape from Thursday through the Memorial Day weekend. Generally cooler to start, with periods of rain Thursday night and Friday, followed by a low-confidence temperature forecast for the weekend.

DISCUSSION

As of 700 AM EDT Wednesday...

KEY MESSAGE 1...Another hot day ahead today, with Thursday also looking quite warm for the southern half of the area. A strong cold front brings the potential for strong to severe storms to northern portions of the area late this evening.

High pressure remains centered well offshore, with breezy S-SW flow across the area this morning. Temperatures are quite mild, with readings averaging 70-75 deg F region-wide as of 07z. Another day of near-record highs is forecast this afternoon, with the record of 97F at RIC looking particularly susceptible to being eclipsed. Upper ridging holds for one more day area- wide, as compressional heating maximizes ahead of an approaching cold front. Strong mixing and ongoing drought conditions will continue to allow early morning dewpoints to mix out by afternoon, falling back into the upper 50s to low 60s and keeping max heat index values generally capped right around actual high air temperatures, which will once again range from the mid to upper 90s inland to the lower 90s closer to the coast under a mostly sunny sky.

As for the well-advertised cold front, multi-model consensus continues to slow its arrival, lagging into later this evening across the north, pushing into southern VA south of US-460 into NE NC later tomorrow morning/early afternoon. 00z CAMs continue to show sparse convection only reaching the far northern and western portions of the area, likely staying out of the RIC metro through much of Wednesday evening. SPC has more or less maintained a Day 1 Marginal Risk (level 1 of 5) for the northern half of the forecast area, though the risk of severe storms over the local area still looks quite marginal. Given the slower timing of the front, it still appears that the better instability and forcing remain to our N/NW. Storm timing over the local area is quite likely to hold off long enough that cells will start to dissipate as they arrive after 00z tonight into early Thursday morning. That said, there remains some potential for a few stronger to severe storms, mainly for far northern portions of the area north of Richmond, over to the Northern Neck, and the MD Eastern Shore. Specifically, the best chance of stronger storms likely comes in the event of convective outflows from more widespread storms to our NNW. Damaging wind gusts are the main threat with any storms that can penetrate the area, though mid-level lapse rates do steepen to 6.5-7 C/km as low levels moisten up this evening. Therefore, an isolated instance of large hail cannot be completely ruled out.

KEY MESSAGE 2...An increasingly unsettled pattern takes shape from Thursday through the Memorial Day weekend. Generally cooler to start, with periods of rain Thursday night and Friday, followed by a low-confidence temperature forecast for the weekend.

A shortwave trough is still forecast to eject northeast across the northern Plains and upper Midwest late tonight, pushing into Ontario and Quebec Thursday. This will serve to dampen the SE ridge, while allowing cool high pressure to settle over the Great Lakes and interior Northeast. Meanwhile, the cold front pushes south through the rest of the area Thursday. The slower frontal timing will allow much of the southern half of the area, mainly south of US-460, to sneak out another very warm day ahead of the boundary as it slowly drops south into the Carolinas later Thursday into Friday. While highs remain in the upper 60s to mid 70s across the northern half of the area, highs well into the 80s are forecast across south-central and southeast VA into northeast NC.

Increasing overrunning moisture and quickly rising PW values will allow rain chances to ramp up quickly Thursday afternoon, especially along and south of US-58. Showers and scattered storms are expected to develop and focus along the front as it drops across the southern third of the area Thursday afternoon into Thu evening, eventually settling over the Carolinas on Friday. In its wake, an emerging cool air/CAD wedge setup takes hold for Friday. Forecast highs remain in the 60s to 70s Friday with periods of mainly stratiform light rain and drizzle.

There is still some uncertainty with respect to the durability of the cool air/CAD wedge setup heading into the weekend. Namely, because of the mid-level ridging, there is a growing signal that the warm front remains pinned to our south a bit longer, therefore holding the wedge airmass in place into the weekend. This injects a bit more uncertainty into temperatures for Saturday, and possibly Sunday as well, as stable, low-level NE marine flow persists. Eventually, the warm front does lift back north over the area to fully erode the CAD airmass Sunday and Monday. Stagnant flow will then likely result in that weakening frontal boundary getting hung up over northern portions of the area late in the holiday weekend into early next week. This leads to the potential for continued unsettled conditions lingering throughout the holiday weekend. Cooler temperatures than currently in the forecast are quite possible for both Saturday and Sunday, though quick warming is likely heading into early next week as mid-level ridging rebuilds east of the Rockies.

The unsettled pattern will allow for rain chances virtually every day from Thursday through the middle of next week. While the weekend certainly doesn't look to be a washout, rain chances will be higher than they've been of late each day into the middle of next week. Hopefully holiday plans won't be interrupted, but at this stage in the ongoing drought, any rainfall is welcome!

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

As of 655 AM EDT Tuesday

VFR conditions prevail for the 12z/20 TAF period. Clear or mostly clear skies are forecast for the bulk of the forecast period, with clouds increasing from the NW this evening ahead of an approaching cold front. There's a low- end chance for showers/storms to impact RIC/SBY toward the tail end of the period, with chances remain much too low for inclusion in the TAF at this time. Rain chances increase at SBY after 00z/8pm this evening into early Thu morning, but likely hold off at remaining terminals until Thu afternoon. SW winds ~10kt through the period, with occasional gusts to 20 kt through this afternoon.

Outlook: Flight restrictions are possible starting early Thu morning as a cold front brings showers and isolated storms to the local area. An unsettled pattern will likely bring additional restrictions through the end of the week and into the weekend.

MARINE

As of 315 AM EDT Wednesday...

Key Messages:

- Sub-SCA conditions are expected across the local waters today and tonight.

- A front crosses the waters Thursday morning, bringing the next chance at SCA conditions from Thursday through Friday due to NE winds of 15-20 kt with gusts to 25 kt.

High pressure remains stretched across the Southeast this morning, producing SW winds of 10-15 kts across the local waters. This stagnant pattern will allow winds to remain primarily SSW around 10 to 15 kt. with some gusts to 20 kts in the Bay and coastal waters late this afternoon and into this evening. This pattern will finally start to break down as a cold front approaches the area late tonight into Thursday morning. This cold front is currently forecast to cross the waters some time early Thursday with increasing NE winds in its wake. Guidance continues to trend upwards with wind speeds, as the front is forecast to stall across our just south of our area. Gradient winds will remain elevated through Friday, but may struggle to increase as much in the southern waters due to the location of the front. NE winds will average 15-20 kt with gusts to 25 kt from Thursday through Friday. SCAs appear likely for portions of the bay (due to winds) and coastal waters N of the VA-NC border (due to seas building to 5-6 ft behind the front). Local wind probabilities show a relatively high (60-90%) chance of sustained 18 kt winds on the middle/lower bay from Thu-Fri. At this time, the front is progged to lift north Friday night, which will allow winds to diminish this weekend as the gradient relaxes some. If the front lifts more slowly on Friday night into Saturday, the northern waters could still see SCA winds linger through portions of Saturday.

There is a moderate rip current risk for the northern beaches (including Ocean City, MD) today, with a low risk elsewhere. With increasing winds and seas associated with a frontal passage on Thursday, all beaches will see a moderate rip current risk. Increasing seas and lingering stronger winds in the wake of the front will produce a high rip risk at all beaches to end the week on Friday.

CLIMATE

As of 950 PM EDT Tuesday...

Tue 5/19: Richmond tied a record high min (71), and SBY also tied the record high min (70). No record high highs were set or tied.

Another day of near-record to record- breaking heat is expected today, both for record highs and record high minimum temperatures. See below for reference.

Record High Temps for Wed 5/20:

Record High/Year Location 5/20 -------- ---- Richmond 97 (2022) Norfolk 98 (1996) Salisbury 98 (1911) Eliz. City 98 (1996)

Record High Min Temps for Wed 5/20:

Record High Min T/Year Location 5/20 -------- ---- Richmond 71 (2018) Norfolk 73 (1996) Salisbury 70 (2018) Eliz. City 73 (2018)

AKQ WATCHES/WARNINGS/ADVISORIES

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