textproduct: Wakefield

WHAT HAS CHANGED

There remains a conditional severe threat Wednesday afternoon and evening. SPC maintains a Marginal Risk (level 1/5) for the entire area, now with all threats possible.

KEY MESSAGES

1) Widespread showers and some storms are expected Wednesday. A few storms could be strong to severe.

2) Mainly dry to end the week, with rain chances returning by Saturday, though drought conditions are also likely to persist. Temperatures hover near or just below seasonal averages.

DISCUSSION

As of 310 PM EDT Tuesday...

KEY MESSAGE 1...Widespread showers and some storms are expected Wednesday. A few storms could be strong to severe.

A surface low pressure tracks over the Ohio Valley to the northeast with a weaker low forming along the cold front Wednesday. A warm front associated with the weaker low will push north through the area bringing a first batch of widespread showers to the area in the morning. There is potential for a few strong to severe storms to develop Wednesday afternoon to evening over the entire local area. The morning showers will be light but will play an important factor into whether or not strong to severe storms develop in the afternoon to early evening. The amount of clearing behind the showers will impact the levels of instability as the second disturbance of the cold front crosses the area in the afternoon to evening. Likely, the piedmont will see the most amount of clearing during mid day. Should this midday clearing occur, the combination of modest destabilization and 30-35kt of 0-6km bulk shear would support organized storm development. Mid level lapse rates between 6-7 C/km could allow for sustained updrafts, posing a risk for damaging winds and possibly large hail. SPC maintains a Marginal Risk (level 1/5) for the area, and now highlights large hail as a possible threat, mostly west of I-95, in addition to a non-zero risk of tornadoes and damaging winds.

KEY MESSAGE 2...Mainly dry to end the week, with rain chances returning by Saturday, though drought conditions are also likely to persist. Temperatures hover near or just below seasonal averages.

A slow moving upper level low over the upper Great Lakes into Ontario drifts across northern New England into. At the surface, weak high pressure over the Central Plains will influence the weather through late week. Temperatures will be around or slightly below average with highs in the lower 70s. Then this weekend, a surface low pressure will form over the southeast coast, which could bring some additional rain to portions on the area on Saturday. The latest ensembles show the possibility of a light rainfall, but probs of 0.1" are 40-70% , so not expecting a drought buster by any means.

MARINE

As of 230 PM EDT Tuesday...

Key Messages:

- Small Craft headlines remain in effect for all ocean zones due to lingering 5 foot seas, highest offshore.

- A cold front approaches the region Wednesday and crosses the waters early Thursday with increasing NW winds behind the front.

- Nuisance to low-end minor tidal flooding is possible Wednesday night for the upper Bay.

Weak high pressure is centered offshore this aftn. The wind is light and generally E/SE 5-10kt. Seas are 3-4ft nearshore and 4-5ft offshore out near 20nm, and 5-6ft in the offshore waters. Waves in the Ches. Bay are ~1ft and 2-3ft at the mouth of the Bay. The pressure gradient tightens later this aftn/evening with a SE wind increasing to 10-15kt for a few hours, before becoming S and diminishing later tonight. The pressure gradient further tightens on Wednesday with SE flow around 15 kt and gusts 20 kt. Showers and tstms are possible along and ahead of the front with gusty winds the main threat. The flow becomes NW and strengthens to 20-25 kt with gusts 25-30 kt behind the front by early Thursday. Waves increase to 3-4 ft in the post-frontal NW surge on Thursday. High pressure builds back into the area later Thursday into Friday.

SCA headlines remain in effect for the coastal waters through early Wednesday morning due to 5 ft seas (highest out near 20 nm). Guidance continues to run quite a bit above buoy observations, but have coordinated with neighboring offices to allow headlines to continue through tonight. Seas will build again Wednesday night into Thursday in the post-frontal NW flow but the highest seas should become confined to areas well away from the coast in offshore flow.

Coastal Flooding...With elevated seas into midweek, and a modest increase in southerly flow Wednesday, some minor to nuisance tidal flooding will be possible across the upper Bay from Lewisetta to the Bayside of the MD Eastern Shore with the high tide cycle Wednesday evening/Wednesday night.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ650-652- 654-656-658.