textproduct: Wakefield

SYNOPSIS

High pressure gradually drifts offshore today. A strong cold front brings widespread showers and potentially gusty winds to the area Thursday night into early Friday. Drier weather and high pressure returns for the weekend, with temperatures near seasonal normals.

NEAR TERM /THROUGH TONIGHT/

As of 200 AM EST Wednesday...

Key Message:

- Dry weather and above normal temperatures today.

Early this morning, high pressure is centered over the southeast US states, extending northward into the local area. Temperatures this morning are generally in the mid 20s to mid 30s (low to mid 20s across the interior MD Eastern Shore). Skies are mainly clear, though a few higher clouds may sneak in from the west as a weak, dry cold front approaches. The approaching front will also allow for a light SW breeze to develop this morning, keeping temperatures steady or even rising as we head towards sunrise.

High pressure builds south of the area this morning before slowly sliding offshore later this afternoon-evening. A dry cold front will also move through, with the surface reflection most apparent on the models across northern portions of the area. The main impact will be increasing mid-high level cloud cover, especially later today. Today will be milder compared to what it has been recently with highs in the low to mid 50s (a few degrees above average). Tonight will see low temperatures fall back into the lower 30s inland (upper 20s over interior portions of the MD Eastern Shore) to the upper 30s closer to the coast.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/

As of 200 AM EST Wednesday...

Key Messages:

- A widespread rainfall is expected Thursday evening into Friday morning with amounts ranging from 0.50" to 1.00" (locally higher).

- Winds become gusty both Thursday night ahead of the front and Friday in the wake of the front.

A split flow pattern develops on Thursday with a southern stream trough advancing along the Gulf coast, while a deep upper trough slides through the Midwest and northern Plains states. The latter of these features will be the most responsible for wet weather and gusty winds later Thursday into early Friday as a strong cold front moves through the region. The forecast for the first part of Thursday is on the tricky side as a residual CAD setup may linger over portions of the Piedmont through most of the day, potentially keeping these areas cooler. For now, the blended guidance is on the warmer side, but will need to monitor trends in the guidance in case any downward adjustments are needed. Meanwhile, across the SE, there is higher confidence in temps warming into the upper 50s to lower 60s.

The strong cold front crosses the area late Thursday night into Friday morning. Ahead of the front, strong WAA/southerly flow is expected, with many areas seeing rising overnight temperatures as a result. High temperatures may be achieved in many locations, especially the NW half of the area, during the overnight hours. In addition, PWATs surge to 1.25" to 1.50"+ which are 200%+ higher than typical late December values. This will set the stage for a period of moderate to locally heavy rainfall Thursday night. QPF has trended upwards on recent model/ensemble runs, with a widespread 0.50" to 1.00" of rain now expected. Locally higher amounts in excess of 1.00" are possible, especially in areas of convective enhancement. It's currently too early to pinpoint where these higher amounts could occur, but currently most likely across the SE where MUCAPE (while negligible) will be highest. Gusty winds will also be possible Thursday night due to a tightening pressure gradient and a LLJ ramping up to 50-60 knots. Gusty S/SW winds of 25-35 mph will be possible, especially closer to the coast, but a low-level inversion should help to keep any stronger gusts from mixing down. It should be noted that if any convective elements are able to develop, a few stronger gusts will be possible.

The front clears the area by mid Friday morning with rain coming to an end from west to east. Skies clear out quickly behind the front, with mostly sunny skies expected areawide by early Friday afternoon. Strong CAA is expected behind the front with W/NW winds gusting to 25 to 35 mph through the afternoon. High temperatures for the day will likely occur first thing in the morning, with falling temperatures later in the day as colder/drier air filters back into the area. Low temperatures drop back into the 20s (inland) with diminishing winds and mostly clear skies Friday night.

LONG TERM /SATURDAY THROUGH TUESDAY/

As of 200 AM EST Wednesday...

Key Messages:

- Seasonable temps continue on Saturday, then potentially mild on Sunday ahead of another cold front.

- Trending milder again next week.

Mostly dry and seasonable through the weekend and early next week as the flow aloft flattens out and high pressure builds back into the area. A bit chillier on Saturday with highs ranging from the mid 40s north to the lower 50s south. Briefly milder weather is possible on Sunday in advance of another cold front (which appears to be mainly dry at this time) with highs ranging from the low-mid 50s north to around 60F south. Temps drop back down to near/slightly below seasonal averages on Monday behind that front. No big storm systems are on the horizon for at least the next week or so. Additionally, while day-to-day details will need to ironed out, there is increasing confidence in a milder pattern as we head into the middle and end of the holiday week.

AVIATION /07Z WEDNESDAY THROUGH SUNDAY/

As of 1230 AM EST Wednesday...

VFR conditions will prevail at all terminals through the 06z/17 TAF period. Mostly clear skies will give way to SCT-BKN upper level cloud decks by this afternoon afternoon, but no precipitation is expected. Winds will be light from the southwest this early morning, followed by a gradual increase later this morning into the afternoon. Occasional gusts to 15-20 kts are possible through the early evening. Upper level cloud cover will remain with us into tonight.

Outlook: The next chance of sub-VFR conditions, along with gusty winds and low-level wind shear, is Thursday night-Friday AM due to showers ahead of a strong cold front. VFR and mainly dry weather will return later Friday through the weekend.

MARINE

As of 230 AM EST Wednesday...

Key Messages:

- Small Craft Advisories remain in effect across the Chesapeake Bay, lower James River, and coastal waters north of Parramore Island today.

- A Gale Watch has been issued for the coastal waters north of Parramore Island from Thursday night into Friday night.

- Another period of elevated SW winds is possible Saturday night into Sunday across the northern coastal waters.

Latest surface analysis depicted high pressure centered off the Southeast coast, extending across inland portions of the Southeast. Winds early this morning were SW 10-15 kt. The pressure gradient increases between a strong low well north of the Great Lakes in Canada and the high across the Southeast later this morning. This should allow SW winds to increase to 15-20 kt later this morning into this afternoon with gusts up to 25 kt possible across the coastal waters north of Parramore Island. Meanwhile, waves and seas of 1-2 ft and 2-3 ft respectively build to 2-3 ft and 3-5 ft respectively later today. As such, SCAs remain in effect across the Ches Bay, lower James River, and coastal waters north of Parramore Island. However, will note that confidence has decreased in SCA conditions being realized, particularly across the lower James River. SCAs end by 1 PM across the Ches Bay and lower James River and 7 PM across the N coastal waters. Winds diminish this afternoon before becoming light and variable tonight as a weak cold front drops south.

Winds become SE Thu as the front lifts back N as a warm front ahead of the next system. A strong area of low pressure moves across the Great Lakes into Quebec Thu into Fri, pushing a strong cold front across the local waters Fri. Elevated winds and seas are likely both ahead of and behind the front with confidence increasing in Gale conditions across at least the northern coastal waters north of Parramore Island. Wind probs for 34 kt gusts have increased here to 60-90%+ Thu night. As such (and in collaboration with neighboring offices), have issued a Gale Watch for Thu night through early Fri night to account for the Gale potential both ahead of and behind the strong cold front. Will note that while southerly Gales are uncommon this time of year given the near-surface stable layer hindering mixing due to cold water temps, local research has shown that pressure falls >10mb/6hrs can overcome the poor mixing in the near- surface stable layer. The NAM and GFS show 10-12mb 6 hour height falls and ~10mb height falls respectively across this area, increasing confidence in at least a period of Gale conditions. Will note that while wind probs are technically lower for the NW surge behind the front, given the strength of the low (potentially <980mb) and favorable mixing with CAA over the local waters (as opposed to WAA), confidence is higher in Gale conditions behind the cold front late Fri into Fri evening, which is why the Gale Watch covers both surges even though there could be a several hour period of sub-Gale conditions in between surges.

Elsewhere, high-end SCA conditions are favored given a slightly weaker pressure gradient and wind field farther south from the low. However, a brief period of 34 kt gusts is possible with the southerly surge across the coastal waters from Parramore Island to Cape Charles Light Thu night (wind probs for 34 kt gusts averaged around 50%). Otherwise, the CAA surge behind the cold front has the potential for low-end Gale conditions farther south from the current Gale Watch (including the Ches Bay), however, confidence is too low to expand the watch any farther south at this time. Winds diminish later Fri night as CAA wanes. Another period of SCA conditions due to SW winds of 15-25 kt is possible Sat evening into early Sun.

Outside of a brief period of 4-5 ft seas possible across the N coastal waters today, seas remain below 5 ft through Thu. Seas quickly build to 5-9 ft Thu night into Fri before subsiding late Fri night into Sat due to the elevated winds ahead of and behind the cold front. Meanwhile, waves build to 3-5 ft. Another period of 4-6 ft seas is possible across the N coastal waters Sat night into Sun.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 1 PM EST this afternoon for ANZ630>632-634. Small Craft Advisory from 7 AM this morning to 1 PM EST this afternoon for ANZ638. Small Craft Advisory from 7 AM this morning to 7 PM EST this evening for ANZ650-652. Gale Watch from Thursday evening through late Friday night for ANZ650-652.