textproduct: Wakefield

WHAT HAS CHANGED

SCA added for the southern Ches Bay and lower James River through early Sunday.

KEY MESSAGES

1) Continued dry with seasonable temperatures through the middle of next week.

2) Elevated tidal anomalies continue tonight into Sunday.

DISCUSSION

As of 310 PM EDT Saturday...

KEY MESSAGE 1...Continued dry with seasonable temperatures through the middle of next week.

GOES water vapor channels depict a highly amplified upper ridge that extends from the central US northward toward James Bay in Canada. This ridge will be strong enough to keep the upstream troughing over the Desert SW from getting east of the Plains states through the middle of next week. Meanwhile, light northerly flow aloft will continue across the local area through Sunday, before weak shortwave energy passes through and moves off the SE coast Sunday night, which will allow the longwave pattern to dampen to some extent with the ridge becoming broader and flatter with the axis in vicinity of the Great Lakes. At the surface, 1035mb high pressure is centered over eastern PA and NJ this afternoon. Partly cloudy with SCT to BKN cumulus/stratocumulus. Temperatures are in the lower to mid 60s with a NE wind of 5-10 mph inland, and 10-15 mph with gusts up to 20 mph toward the coast.

The high continues to gradually build south and into the local area tonight. For tonight into early Sunday morning, temperatures should be slightly lower with mid 30s NW and upper 30s to lower 40s for most of central and south-central VA. Patchy frost is expected for areas to the N and W of Richmond, and interior portions of Dorchester and Wicomico counties in MD. However, coverage and overall threat is not quite enough to warrant a Frost Advisory at this time. As the high continues to settle in from the north Sunday, cloud cover should be less, but a period of SCT-BKN cumulus are still likely along and S of I-64. Temperatures warm a few degrees with highs in the mid 60s to near 70 F. Sunday night/early Monday morning will likely see the greatest potential for a more widespread frost spreading east from the piedmont to interior SE VA as better decoupling is expected. Continued the same thinking as the previous shift to go a few degrees (or several degrees in some areas) colder than NBM, with mid 30s forecast for much of the piedmont and and mid- upper 30s for interior SE VA.

Warmer Monday ahead of the next (dry) front, then slightly cooler into midweek and staying dry. The 24/12z ECMWF ensemble/GEFS chance for just .01" of rain through mid week is basically none, with some low probs showing up in southeastern portions of the area later in the week into the following weekend, but when switching the threshold to 0.1" there are practically no probs through the end of the month.

KEY MESSAGE 2...Elevated tidal anomalies continue tonight into Sunday.

Coastal Flood Advisories continue until 4 PM for portions of the bay side of the MD Eastern Shore as well as the south bank of the Potomac. Tonight's tide cycle will be the lower of the two upcoming high tides. Expecting mostly nuisance-level flooding tonight, though Lewisetta and Bishops Head will come close to minor thresholds. Persistent NE winds near the mouth of the bay, along with slowly decreasing swells have resulted in only a slow decrease in tidal anomalies, especially for the middle and upper Ches Bay. Sunday's high tide will likely exceed minor flood thresholds in some of these areas. Additional Coastal Flood Advisories are possible as increasing astronomical tides counteract decreasing anomalies.

AVIATION /19Z SATURDAY THROUGH THURSDAY/

As of 140 PM EDT Saturday...

1035mb high pressure was centered over eastern PA/NJ as of 18z. VFR with bands of CU/SC (bases of 4-5kft). The wind was NE 8-12kt, with gusts to ~20kt along the coast. VFR conditions are expected to prevail for the 24/18z TAF period. The wind will remain NE tonight and become very light inland and 5-10kt along the coast with FEW-SCT clouds. The wind remains NE Sunday as the high gradually builds southward. Less cloud cover is expected Sunday and should mainly be confined to the southeastern terminals.

Outlook: VFR conditions continue Sunday night through later next week. Lighter N to NE winds are expected on Monday. Elevated NE winds return Tuesday and Wednesday.

MARINE

As of 310 PM EDT Saturday...

Key Messages:

- Elevated winds and seas will continue through the weekend, especially across the central and southern waters, with elevated seas lingering into early next week for the southern waters.

1034mb high pressure over eastern PA/NY continues to slowly build southward this afternoon. Low pressure well to the south is allowing for elevated NE winds to continue across the local waters. Winds are mainly 15-20 kt with gusts to 25 kt, highest across the ocean and southern Ches Bay/James. Waves are 2-3 ft with 3-4 ft at the mouth of the bay. Seas are 3-5 ft N and remain 6-9 ft S where NE winds are strongest.

Winds in the southern Ches Bay/lower James have been very slow to subside today and are hovering near SCA thresholds. The latest guidance shows winds roughly holding steady at their current level this evening and even bumping up a few knots tonight. Therefore, have issued Small Craft Advisories for the southern bay and James through 7 AM Sunday. SCA headlines remain in effect for the mouth of the bay and nearshore coastal waters tonight. High pressure will move over the region on Monday, finally allowing winds/seas to subside. The reprieve looks to be short-lived unfortunately, with new high pressure building into the Great Lakes region by midweek. In this type of setup, even very weak low pressure/troughing off the Southeast coast will result in elevated NE winds returning to the region. Seas will slowly decrease from N to S tomorrow into Monday but may not fall below 5 ft for the southern waters before the next bout with increasing NE winds allows seas to build once again.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...Coastal Flood Advisory until 4 PM EDT this afternoon for MDZ021>023. NC...None. VA...Coastal Flood Advisory until 4 PM EDT this afternoon for VAZ075-077. MARINE...Small Craft Advisory until 7 AM EDT Sunday for ANZ632-639-650- 652. Small Craft Advisory until 7 PM EDT Sunday for ANZ634. Small Craft Advisory until 6 AM EDT Monday for ANZ654-656-658.