textproduct: Wakefield

WHAT HAS CHANGED

- Increased high temperatures a degree or two today.

- Lowered high temperatures for Thursday.

- Confidence in Gale conditions Friday night and Saturday continues to increase.

KEY MESSAGES

1) Very warm temperatures will easily challenge and likely break high temperature records across the region this afternoon.

2) A cold front drops southward Thursday with cooler temperatures for most of the area.

3) Warm and breezy Friday with a few showers before much cooler temperatures arrive this weekend.

DISCUSSION

As of 255 AM EDT Wednesday...

KEY MESSAGE 1...Very warm temperatures will easily challenge and likely break high temperature records across the region this afternoon.

1020mb high pressure dominates the local weather pattern this morning. A cold front extends from low pressure over NY to the W/SW into the Ohio Valley and Great Lakes. Strong upper ridging is centered over the Gulf Coast but is extending to the NE with rising heights aloft over the Mid-Atlantic. A weak shortwave trough is currently clipping NE portions of the area, with mostly just a temporary increase in clouds but a few light returns have been noted on radar over the last few hours. These clouds and any lingering light rainfall will move offshore over the next few hours.

The main weather story today will be the well above normal temperatures. Heights aloft hold steady or rise slightly through the day while low level flow will continue out of the W and SW. Clear or mostly clear skies and some downslope compressional warming will combine for high temps in the upper 80s to low 90s across the region. Blended guidance continues to be 2-4 degrees below the statistical guidance. Will go with highs 90-93 degrees for inland locales with mid/upper 80s for the Eastern Shore. These values are well above the record temps for the day at all of our long term climate sites (which are 86-87 degrees, all set in 1975). See the Climate section below for site-specific data. Forecast soundings show ample dry air aloft, however, which will allow dew points to mix out into the low/mid 60s this afternoon and keep the heat from feeling too oppressive. Clouds will increase across the N this evening as the aforementioned cold front creeps slowly south.

KEY MESSAGE 2...A cold front drops southward Thursday with cooler temperatures for most of the area.

A cold front will approach the region from the N tonight and is forecast to cross the local area early Thursday. High pressure over the Great Lakes will translate eastward and allow for a CAD wedge to develop over much of the area. Have continued the trend of lowering temperatures vs the blended guidance with widespread clouds forecast over the northern 2/3 of the area by early afternoon with NE/onshore flow. Latest guidance continues to show the potential for some light isentropic lift across the northern counties Thursday. QPF still looks quite meager with a few hundredths to perhaps a tenth of an inch forecast. High temperatures now range from the mid 60s N to the low and mid 70s from Richmond S. Areas near and south of the VA/NC border may still make it into the upper 70s to low 80s with thicker cloud cover arriving a few hours later than points N. Temps will not follow the typical diurnal curve over much of the area with highs likely to occur in the morning or early afternoon.

KEY MESSAGE 3...Warm and breezy Friday with a few showers before much cooler temperatures arrive this weekend.

A deep upper trough is forecast to dig across the Great Lakes Thursday night into Friday with a strengthening surface low over the Ohio Valley. Southerly flow ahead of this feature will allow the front to lift back northward as a warm front Friday morning. High temps rebound into the low 80s N with mid and upper 80s S. It will become breezy out of the SW by Friday afternoon. Some showers and thunder are also possible, primarily across NE portions of the area Friday afternoon. Rapidly deepening low pressure will translate NE into New England on Friday with a strong cold front extending back to the southwest. This front will cross the local area Friday evening into early Saturday with significant cold advection moving into the region. Some additional precip is possible along and ahead of the frontal passage, mainly over the eastern half of the area before sunrise. QPF does not look nearly as impressive as a front of this strength would suggest. Gusty winds are likely to continue into the Friday overnight period and could reach 35-40 mph immediately along and behind the front. While kinematic fields will be favorable for storm organization, lack of deeper moisture/instability will limit the potential for strong to severe convection (or even much thunder) across the region.

Strong (1035mb+) high pressure builds into the region behind the front with upper troughing remaining over the eastern CONUS, resulting in well below normal temperatures this weekend. Afternoon highs likely struggle to get out of the 50s across the northern half of the CWA despite mostly sunny skies. Low 60s are forecast for the southern half of the area. It will also remain quite breezy on Saturday with gusts 25-30 mph, and especially near the coast where winds could gust 30-35 mph. Overnight low temps tumble into the mid to upper 30s in the Piedmont with low to mid 40s for the remainder of the area Saturday night. Upper 30s and low 40s are forecast Sunday night into Monday. Some frost is possible in the Piedmont with this airmass, especially if temps continue to trend toward the cooler MOS guidance which shows temps in the low 30s in the typically cooler spots.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

As of 650 AM EDT Wednesday...

VFR prevails through most of the 12z TAF period. SW winds 5-10 kt today with mostly clear skies. A cold front drops south tonight with winds becoming N then NE behind the boundary. Some MVFR CIGs are possible late, mainly at SBY and perhaps RIC.

Outlook: A cold front drops south later tonight into Thursday, bringing increased cloud cover and low-end rain chances to portions of the area. Sub-VFR CIGs are possible Thursday into Friday morning as a wedge pattern develops over the area. Another cold front crosses the area Friday into Saturday, bringing additional rain chances and gusty NW winds.

MARINE

As of 255 AM EDT Wednesday...

Key Messages:

- NE winds behind a backdoor cold front will gust 20-25kt for a few hours Thurs morning.

- A strong cold front crosses the waters late Friday into this weekend. Strong SCA to Gale conditions are likely Friday night through early Sunday.

Early morning sfc analysis indicates high pressure being suppressed to to the SE with low pressure over New England. The pressure gradient between these features is tight enough to support SW winds of 10-15kt. Latest buoy obs show seas of 2 to 3 feet and waves in the bay around 1ft. SW flow will continue through the day and part of tonight, diminishing slightly to 5-10kt this afternoon.

A backdoor cold front will drop south across the area late tonight into Thurs morning and will reach southern waters around mid day. Winds turn to the NE behind the front and increase to 15-20kt with strongest winds off the coast of the Eastern Shore. There will likely be a few hours of gusts around 20kt in the lower bay and lower James River Thurs morning, so SCAs may be needed. Confidence in the stronger winds lasting more than an hour or two is fairly low, so will hold off on issuing anything for now so we can get another round of high-res models. Seas will increase to 3-4ft Thurs and waves in the bay to 2-3ft. SW flow returns Thurs night/early Fri when the backdoor front is lifted back north ahead of a stronger cold front that will pass through Fri night.

SSW flow ramps up to 15-20kt again on Friday as the pressure gradient tightens ahead of the stronger front. Strong CAA behind the front over the still-warm waters will lead to the potential for gale conditions Fri night through much of Saturday. Local wind probs for sustained gale force winds are still pretty low to non-existant with only ~15% for a few spots over the coastal waters. Probs for 34kt+ gusts, though, are much higher and peak at 70-90% over the bay and coastal waters early Sat morning. Latest forecast is for NW winds of 25-30kt (20-25kt on the rivers) and gusts of 30-38kt. Still too early to put up Gale Watches, but they will likely be coming in the new couple of days for the Friday night-Saturday periods. Seas should build to 5-7ft and waves in the bay to 5-6ft during this period. Strong high pressure is quick to build in behind the front, so winds should drop off rather quickly Sat night into Sunday.

CLIMATE

Record High Temperatures:

10/14 RIC 87/1975 ORF 86/1975 SBY 86/1975 ECG 86/1975

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...None.