textproduct: Wakefield

WHAT HAS CHANGED

Breezy today as the pressure gradient tightens between high pressure offshore and low pressure near the Great Lakes.

SCA headlines have been issued for marine zones north of the VA/NC border.

KEY MESSAGES

1) Dry with seasonable temperatures today and Saturday. Breezy conditions develop this afternoon. A few showers are possible Sunday afternoon, but otherwise remaining mild along the coast, warmer inland.

2) Another strong cold front approaches early next week, bringing the potential for strong to severe storms Monday, with below normal temperatures to follow.

DISCUSSION

As of 330 AM EDT Friday...

KEY MESSAGE 1...Dry with seasonable temperatures today and Saturday. Breezy conditions develop this afternoon. A few showers are possible Sunday afternoon, but otherwise remaining mild along the coast, warmer inland.

High pressure is centered over the region early this morning with strong low pressure noted over the upper Midwest. Temperatures are much colder than recent days with mainly upper 20s and low 30s on area observations. Patchy fog and/or freezing fog has been transient so far this morning with highly variable visibility noted at observation sites.

High pressure moves offshore this morning, allowing winds to become southerly after sunrise. The gradient tightens as Midwest low pressure translates eastward today. Southerly winds will increase to 15-20 mph with gusts 25 to 35 mph this afternoon. Expecting mostly clear to partly cloudy skies this afternoon with temps rebounding into the mid and upper 50s inland and around 50 degrees for the Eastern Shore. A few spots in NE NC may warm into the low 60s. Not as cold tonight with lows in the 40s. Slightly warmer on Saturday with less wind and highs mainly in the 60s. Low pressure deepens considerably over the central CONUS on Sunday with increasing temps and humidity across the local area. A few showers are possible for S and SW portions of the area late Sunday afternoon but PoPs do not increase substantially until Sunday evening into the overnight hours.

KEY MESSAGE 2...Another strong cold front approaches early next week, bringing the potential for strong to severe storms Monday, with below normal temperatures to follow.

00z models remain in decent agreement depicting a strong mid/upper level trough, almost becoming cutoff near the Great Lakes by Monday evening. At the sfc, intense low pressure is forecast to lift NE from the mid-MS/lower OH Valley to the Great Lakes late Sun night/early Mon. Models show this low occluding as the surface and upper level features stack vertically. Latest guidance continues to show a deepening trough along the Appalachians on Monday which may allow surface winds to remain S or even SSE ahead of the cold front. Strong deep layer shear will be in place due to impressive wind fields aloft and would be augmented further by any degree of low level backing from the developing surface trough. Instability is more uncertain with most models showing widespread clouds and showers ahead of the front, which will limit surface heating. However, strong southerly flow will advect increasing low level moisture into the region ahead of the front with dew points increasing into the low/mid 60s. Strong kinematics aloft and forcing along the cold front will promote a mainly linear convective mode across the region with strong straight line winds likely the primary threat. Given the degree of deep layer shear and potential for increasing low level shear, QLCS tornadoes are also a possibility as the line crosses the region.

The airmass behind this system will be much cooler and significantly drier. Highs mainly in the 40s Tue-Wed, with hard freeze probable for much of the area Tue night. Gradually trending warmer by late in the week.

AVIATION /07Z FRIDAY THROUGH TUESDAY/

As of 215 AM EDT Friday...

Challenging aviation forecast early this morning with fairly widespread shallow ground fog/freezing fog on area observations. Not at all confident in sustained IFR outside of PHF through sunrise. Went with prevailing IFR at PHF through 09z and MVFR thereafter given how that particular ASOS typically performs vs guidance. Brief IFR is possible at RIC and ORF but VFR should prevail. Any ground fog should mix out quickly after sunrise with increasing southerly winds through mid morning. The gradient tightens late morning through the afternoon as strong low pressure passes by well to the north of the local area. S winds mainly 15-20 kt with gusts 25-30 kt (highest inland and N). Gusts should calm down with the loss of mixing. LLWS is highlighted at RIC, SBY, and ORF this evening. Did not mention LLWS at PHF and ECG as the duration appears to be shorter than the other terminals this evening. Will likely add LLWS with the 12z TAFs.

Outlook: VFR conditions persist into early Sunday. A strong cold front will bring the potential for flight restrictions in SHRA/TSRA Monday, along with strong, gusty southerly winds.

MARINE

As of 330 AM EDT Friday...

- Small Craft Advisories are in effect north of the VA/NC border this afternoon into tonight in advance of a weakening cold front.

- A strong cold front approaches from the west Monday and crosses the coast Monday night. Small Craft Advisory conditions are likely with gale conditions possible. Additionally, strong thunderstorm wind gusts are possible.

High pressure is centered in vicinity of the Mid-Atlantic coast early this morning. The wind is at or below 10kt out of the W/NW. Seas range from 2-3ft N of the VA/NC border, to 3-4ft S of the VA/NC border with 1-2ft waves in the Ches. Bay. High pressure quickly moves offshore today into tonight as strong low pressure tracks from the Great Lakes toward northern New England. The strongest wind locally will be N of the VA/NC border where the wind is expected to peak at 20-25kt with gusts to ~30kt for the Ches. Bay and MD/VA coastal waters, with 15-20kt with gusts to 25-30kt for the rivers of eastern VA later this aftn and early evening. Sustained 18kt wind probs are near 100% for the Ches. Bay and 60-80% for the rivers. Sustained 25kt wind probs for the coastal waters are 60-100% N of Cape Charles. However, 34kt gust probs are generally less than 30%, aside from a max off the Delmarva coast that is rather short-lived, and this may be difficult to achieve given that SSTs are still only ~40F. SCAs are in effect for all marine zones N of the VA/NC border beginning at noon and gradually tapering off tonight. Seas build to 3-4ft S to 5-7ft N later this aftn into this evening, with 3-4ft waves in the Ches. Bay.

Sub-SCA conditions are expected Saturday into Saturday night as there is minimal CAA in the wake of the cold front associated with the low that tracks N of the region. An ESE, then SE wind increases Sunday into Sunday night with 1030+mb high pressure off the New England coast and strong low pressure well to the W. SCA conditions are possible in the Ches. Bay for wind, and potentially for seas in the coastal waters by Sunday night. Low pressure lifts NE through the Great Lakes Monday with a strong cold front approaching from the W, which then crosses the Mid-Atlantic coast Monday night. High-end SCA conditions are likely, with a period of gale conditions possible in southerly flow ahead of the front and WNW flow immediately behind the front. Additionally, there is a risk for strong thunderstorm wind gusts ahead of the front. Seas build to 5-7ft S to 7-10ft N Monday into Monday night, with 3-5ft waves in the Ches. Bay and locally higher at the mouth of the Bay. More benign marine conditions are expected by the middle of next week as high pressure settles across the region.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from noon today to 4 AM EDT Saturday for ANZ630>632-634-650-652. Small Craft Advisory from noon today to 10 PM EDT this evening for ANZ635>637. Small Craft Advisory from noon today to 1 AM EDT Saturday for ANZ638-654-656. Small Craft Advisory until 4 AM EDT early this morning for ANZ658.