textproduct: Wakefield

WHAT HAS CHANGED

Updated full discussion. No significant changes to the forecast.

KEY MESSAGES

1)Dry, seasonable, and pleasant through the middle of the week.

2) A strong cold front brings chances for rain Thursday-Friday, though rain amounts should remain on the lighter side. Much cooler temperatures follow behind the front.

DISCUSSION

As of 320 AM EST Monday...

KEY MESSAGE 1...Dry, seasonable, and pleasant through the middle of the week.

A dry cold front is currently passing through the area this morning. The antecedent and post-frontal mid and upper levels are very dry, so there aren't even any clouds along or behind the front. Despite the clear skies, a light SW wind is keeping the low-levels just mixed enough to prevent appreciable radiational cooling. Temperatures are generally in the upper 40s to around 50 F and morning lows should just be a few degrees cooler. Rural/sheltered locations could briefly dip into the upper 30s. For today, sunny skies and seasonable temperatures in the 60s are forecast. Breezy WNW winds are also expected in the well-mixed, post-frontal airmass, particularly in the late morning and early afternoon. Wind gusts up to 25 mph or so are possible and could approach 30 mph on the lower MD Eastern Shore. Low temperatures tonight likely drop in the 30s for most of the area, except in the 40s at the immediate coastline. There is some potential for a light freeze in rural interior VA (particularly near the NC/VA border). Frost is also possible in these areas and could eventually need a targeted Frost Advisory for areas still in the growing season.

Otherwise, a dry and pleasant stretch of weather is expected through the middle of this week as high pressure meanders south and southwest of the area. Modest height rises on Tuesday allow for high temperatures a degree or two warmer compared to today, generally in the upper 60s to around 70 F. Similarly mild on Wednesday with even some lower 70s creeping into the forecast across interior portions of eastern VA and NE NC. Expect a gradual increase in clouds late in the day Wednesday as upper- level moisture begins to overspread the area ahead of developing sfc low pressure in the Midwest. Overnight lows in the 30s inland and 40s near the coast Tuesday night and in the 40s area wide Wednesday night.

KEY MESSAGE 2...A strong cold front brings chances for rain Thursday- Friday, though rain amounts should remain on the lighter side. Much cooler temperatures follow behind the front.

The latest model guidance continues to signal a major pattern change at the end of the week. An anomalous 500mb trough develops and digs into the eastern half of the country Thursday into Friday, with a sprawling surface low initially developing in the Midwest and OH River Valley area Thursday. There is some disagreement across the deterministic and ensemble guidance beyond Thursday, but most data shows a Miller B-type evolution, with a secondary sfc low then developing offshore of the area Thursday night as the upper trough pivots toward the Mid-Atlantic. Regardless of the specifics, this would mean that much cooler, below average temperatures are eventually on the way for Friday and the weekend. Highs in the 50s are expected Friday into early next week with Saturday currently looking like the chilliest day. Overnight lows look to be around freezing each night away from the immediate coast and even could briefly dip into the upper 20s. This system also appears likely to bring some rain chances to the area, particularly later Thursday into early Friday. The jury is still out on how much rain we can get out of this system. The ECMWF ensemble remains the most optimistic for a half inch of total QPF, generally 20-40% and 40-60% for the southern and northern halves of the area, respectively. The GEFS and GEPS continue to show little to no probs in this category. In general, areas N/NE of I-64 have the best shot at appreciable rainfall during this time. Drier behind this system for the weekend.

AVIATION /12Z MONDAY THROUGH FRIDAY/

As of 615 AM EST Monday...

A dry airmass will allow for VFR through the upcoming 12z TAF period, as well as for most of the early-midweek period. Outside of a few higher clouds, SKC is forecast today. A W wind early this morning shifts to the WNW/NW (10-15 kt) after 14-15z behind a dry cold front, with gusts to 20 kt possible (25 kt at SBY). Winds decrease this evening and tonight.

Outlook: VFR conditions are expected to continue Tuesday and through the middle of the week. Another cold front approaches from the west, with rain possible by later Thursday and Friday. Some short-lived sub-VFR conditions are possible with the frontal passage, with some strong NW winds and markedly cooler conditions forecast behind the front for Friday and the weekend.

MARINE

As of 320 AM EST Monday...

Key Messages:

- Elevated winds continue today with W winds shifting to the NW. Small Craft Advisories are in effect for the Chesapeake Bay and northern coastal waters through late this afternoon and evening, and through this morning for the southern coastal waters and lower James River.

- Calmer marine conditions return tonight and continue through Thursday.

- Strong NW winds and elevated seas are possible by Friday into the weekend in the wake of a strong cold front, but confidence in details remains low.

High pressure is centered over the Deep South early this morning. Meanwhile, a cold front is pushing SE across central PA and northern VA. The wind is primarily W 10-15kt with gusts up to 20kt ahead of the cold front, and potentially up to 20-25kt offshore. Seas are approximately 3-5ft in the coastal waters, and 5-6ft beyond 20nm. Waves in the Ches. Bay are 2-3ft. The cold front sweeps across the coast this morning with the wind becoming NW 15-20kt with gusts to 25kt for the Ches. Bay and northern coastal waters, and potentially up to 20-25kt with gusts to 30kt offshore of the MD coast. Seas remain 4-5ft in the northern coastal waters through this evening, subside to 3-4ft for the southern coastal waters, and generally 4- 6ft beyond 20nm, and locally 5-7ft beyond 20nm off the MD coast. Waves in the Ches. Bay will primarily be 2-3ft, but should build to 3-4ft in the middle Bay where the NW surge will be maximized today. SCAs remain in effect through this evening for the Ches. Bay and northern coastal waters. Meanwhile, SCAs for the southern coastal waters and lower James River are only in effect this morning.

High pressure builds into the region tonight through Wednesday, before moving offshore Wednesday night into Thursday. Sub-SCA conditions are expected during this timeframe. There is a secondary dry cold front that crosses the coast Tuesday night. A WSW wind increases to 10-15kt across the Ches. Bay and ocean ahead of this boundary Tuesday aftn and early evening, before becoming N behind the front later Tuesday night into early Wednesday morning. High pressure becomes centered over the northern Delmarva Wednesday with the wind becoming light and variable across the northern tier of the marine area, and ENE 5-10kt across the southern tier of the area. The wind then becomes SE Wednesday night and S Thursday as the high moves offshore with speeds 10kt or less. Seas subside to 2-3ft nearshore and 3-4ft offshore by Tuesday, and then 2-3ft for most of the local Atlantic zones by midweek. Waves in the Ches. Bay will be 1 to occasionally 2ft Tuesday through midweek.

Low pressure and a strong cold front push across the coast and offshore Thursday night into Friday, with an extended period of CAA into the weekend. The 09/00z GFS primarily has an extended period of SCA conditions with a W to WNW wind, and the 09/00z GEFS ensemble members are largely following suit with only negligible probs for wind gusts at or above 34kt. However, the 09/00Z ECMWF and CMC have secondary low pressure deepening immediately off the coast Friday night and pushing offshore Saturday. The EPS members are following a similar pattern to the deterministic with ensemble probs for gusts at or above 34kt at 60-80% Friday night into Saturday. Confidence in details remains low. However, an extended period of SCA conditions is likely with a period of gale conditions possible. Seas potentially build to 5-7ft in the coastal waters and 7-9ft beyond 20nm.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 10 PM EST this evening for ANZ630- 650-652-654. Small Craft Advisory until 7 PM EST this evening for ANZ631- 632-634. Small Craft Advisory until 7 AM EST this morning for ANZ639. Small Craft Advisory until 10 AM EST this morning for ANZ656- 658.