textproduct: Wakefield

WHAT HAS CHANGED

Lowered temperatures a bit once again for north and northeastern portions of the area on Thursday. While model signal remains less than clear, discussed weekend coastal storm in slightly more detail.

KEY MESSAGES

1) Warmer today with dry weather expected. Becoming breezy this afternoon, with SW winds gusting to 25 to 30 mph.

2) A back door front drops south and southwestward across the mid-Atlantic coast on Thursday. Developing onshore winds will bring lower temperatures across much of the area, but especially the VA peninsulas and the VA/MD Lower Eastern Shore.

3) Several disturbances bring the chance for rain back to the area Thursday into the weekend.

DISCUSSION

As of 315 AM EST Wednesday...

KEY MESSAGE 1...Warmer today with dry weather expected. Becoming breezy this afternoon, with SW winds gusting to 25 to 30 mph.

Latest surface analysis shows 1024+mb sfc high pressure centered over the western Atlantic. To the north, low pressure continues to slide east across the upper midwest toward the Great Lakes, with a quasi-stationary frontal boundary extending east across the interior northeast into the northern mid-Atlantic. Aloft, low amplitude ridging continues to slide across the Gulf Coast. Some weak perturbations rounding the top of the ridge have allowed some high clouds to move back into the region, and those clouds look to linger through much of the day today. Meanwhile, SSW winds become gusty this afternoon, allowing temps to rise well into the 60s for most of the area west of the Ches Bay, with cooler 50s to near 60 on the Shore. While the vast majority of the area will be dry today, a passing shortwave overrunning the warm front lifting across the region could bring a few afternoon and early evening passing showers over eastern VA and the Lower Eastern Shore.

KEY MESSAGE 2...A back door front drops south and southwestward across the mid-Atlantic coast on Thursday. Developing onshore winds will bring lower temperatures across much of the area, but especially the VA peninsulas and the VA/MD Lower Eastern Shore.

Latest guidance continues to bring the previously referenced front back south into the area from the northeast Thursday, bringing cooler marine air inland behind the sinking boundary. In coordination with neighboring offices, have lowered temperatures a bit more tomorrow from the inherited forecast, ranging from mid 40s for the Eastern Shore, northern neck and VA Peninsulas to the 60s to low 70s for areas roughly along and south of US 460. Further refinements to temperatures are likely as we get closer. PoPs also increase tomorrow afternoon and evening, especially for areas along and north of where the front eventually stalls, which at this time looks to be near US 460.

KEY MESSAGE 3...Several disturbances bring the chance for rain back to the area Thursday into the weekend, along with the potential for a late weekend coastal storm.

The aforementioned front meanders near and south of the local area Thu night into Friday night, before the trailing cold front crosses the area early Saturday. Several disturbances aloft overrunning that boundary will bring periods of rain across the region Friday into Saturday. Friday's system looks to mainly impact the northern half of the area with showers Friday morning into the afternoon, though 30-50% PoPs for scattered rain showers Fri/Fri night still look reasonable across southern third as the front lingers over the region.

The unsettled pattern lingers into the weekend, and as the front sinks south of the area, additional rounds of rain are possible on Saturday. Models are coming into general agreement that a second, stronger disturbance aloft and strengthening coastal low will develop along that boundary on Sun/Sun night before tracking ENE off the mid- Atlantic coast and offshore. While confidence in a storm developing is now high, timing/track and resultant sensible weather impacts are far less certain. The latest run of deterministic models each brought precipitation back closer to the coast Sun night/Monday but are all a bit flatter, more progressive. For their part, the respective AIFS runs are similar to previous, but each a bit flatter/weaker with the developing low. Should this storm come to pass, and there is increasing signal that it will, there is the potential for more widespread moderate to locally heavy rainfall and gusty winds, especially near the coast.

Model ensemble (GEFS/EPS) snow probabilities have increased a bit for 1" of snow over eastern VA and the Eastern Shore. While this remains a rather low- probability scenario, it is somewhat more feasible given the trend toward a stronger upper low, which is modeled to briefly close off this weekend over the interior northeast. Given the lack of much cold air ahead of the event, the most likely scenario remains additional rain and a period of gusty winds later Sun/Sun night. But given the mode amplified upper level trends, this scenario of precipitation ending as some light snow early Monday over the VA Peninsulas and Delmarva cannot be completely discounted at this stage and does bear some watching over the coming days. Should also note that models have trended toward increased blocking in the northern Atlantic, portending a chilly start to next week before the Canadian surface high modifies into the latter half of next week.

AVIATION /08Z WEDNESDAY THROUGH SUNDAY/

As of 115 AM EST Wednesday...

Marine stratus has lifted north of the area to begin the 06z TAF period, with VFR conditions now returned at KSBY. Elsewhere, VFR conditions continue to prevail at all remaining terminals with increasing SCT- BKN high clouds. VFR conditions prevail through the period with CIGs no lower than 8-10 kft AGL. Light and variable winds early this morning become gusty (to 18-22 kt) out of the SW late this morning and this afternoon. A brief period of LLWS is forecast toward sunrise on Wed at RIC.

Outlook: Dry/VFR conditions persist through midweek. A weak backdoor cold front likely impacts the region Thursday-Friday, veering winds to the NNE, with showers and flight restrictions likely by late tonight/early Wed along the coast. Additional rounds of rain are likely Thu into this weekend, as the front returns back north with a series of weak disturbances pushing across the region.

MARINE

As of 315 AM EST Wednesday...

Key Messages:

- Small Craft Advisories in place for all through this evening and tonight.

- A backdoor cold front is likely to drop across the local waters early Thursday with the wind shifting to E-NE.

-Elevated Marine conditions potentially return by the end of the weekend and early next week.

Early morning analysis shows high pressure off the SE coast and a low pressure tracking across the Great Lakes region and moving towards the Northeast. The pressure gradient from this system has tightened allowing winds to increase out of the SW around 10 kt. In addition with the increase of winds it has allowed for visibilities to improve across the northern waters. Therefore, the Marine Dense Fog Advisory has been allow to expire. Waves across the southern two ocean zones are continuing to remain elevated around 4 to 6 ft allowing for the SCA to remain in effect. While north of the Cape seas remain between 3 to 4 ft and across the bay 1 to 2 ft. Through the rest of the morning and throughout tonight the high pressure will move further offshore and the low will track across the northeast. The pressure gradient from this system will tighten allowing for winds to increase to ~15kt and 15-20kt for the ocean during the day. However, due to the nature of the airmass being warm it will limit low-level mixing resulting in lower gusts. Regardless, SCA conditions are expected and SCA have been issued for all waters from 12z today through 00z Thursday for the bay and through 6z Thursday for the coastal waters. Additionally, seas will rise through the day due to the wind and are expected to be between 3 to 5 ft across the ocean zones and 2 to 3 ft across the bay. By tonight and early Thursday morning the low will track to the north and a backdoor cold front dropping across the Mid-Atlantic coast. Winds ware expected to shift ENE and remain below SCA criteria. Thursday night, the front is progged to lift north as a warm front. The pressure gradient may tighten enough to build seas to 4-6ft N of Chincoteague Thursday night into Friday morning. Trailing cold front drops across the coast early Saturday. Then, by the end of the weekend, low pressure is expected to track in vicinity of the Carolina Coast. Strong SCA conditions are likely with gale conditions possible for the coastal waters.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 7 AM this morning to 7 PM EST this evening for ANZ630>638. Small Craft Advisory from 7 AM this morning to 1 AM EST Thursday for ANZ650-652-654. Small Craft Advisory until 1 AM EST Thursday for ANZ656-658.