textproduct: Wakefield

WHAT HAS CHANGED

A Freeze Watch has been issued for inland portions of central and eastern Virginia as well as portions of northeast North Carolina for Friday night into Saturday morning.

KEY MESSAGES

1) Isolated to scattered showers are possible this afternoon.

2) Much cooler temperatures arrive Friday into early next week with below freezing overnight temperatures likely inland. A Freeze Watch has been issued for portions of the area for Friday night into Saturday morning.

DISCUSSION

As of 215 PM EST Thursday...

KEY MESSAGE 1...Isolated to scattered showers are possible this afternoon.

Latest surface analysis depicted an area of low pressure centered over SE PA/NE MD with a cold front beginning to push into portions of the Piedmont. Temps as of 150 PM ranged from the upper 60s to lower 70s. The low will continue to move NE away from the area through Friday with the associated cold front pushing across the local area later this afternoon. Aloft, an anomalously strong trough was noted across the eastern CONUS and will linger across the region into early next week. CAMs continue to show isolated to scattered showers developing over the next few hours from west to east ahead of the cold front. However, dew points have mixed out into the mid 40s across the Piedmont which has resulted in lower CAPE than originally modeled. As such, confidence in robust convection has decreased. However, have kept 15-25% PoPs across most of the area and 25-40% PoPs across the lower MD Eastern Shore given the favorable upper-level support, mid-level lapse rates, and low level forcing along the front. Nevertheless, any rainfall is expected to be very light with <0.1" expected. Most areas may struggle to even see a few hundredths of an inch of rain. Any showers move offshore this evening. Will note that the HRRR and NBM show the potential for bay streamer showers across the Eastern Shore on Friday. Otherwise, most of the area will remain dry on Friday. Given elevated winds and cloud cover tonight, lows likely remain in the low-mid 40s for most of the area.

KEY MESSAGE 2...Much cooler temperatures arrive Friday into early next week with below freezing overnight temperatures likely inland. A Freeze Watch has been issued for portions of the area for Friday night into Saturday morning.

An anomalously strong (-2 to -3 standard deviations) upper trough settles over the area Friday into the weekend. While the core of the trough moves offshore early next week, overall troughing continues through early next week. As such, the coolest weather of the season (so far) is still expected to arrive Friday and continue into early next week. Daily highs in the 50s with lows near or below freezing are expected for that stretch. Will note that low temperatures have been raised slightly for Friday night given elevated winds and perhaps partly cloudy skies at times. As such, the NBM appears to be too low compared to other model guidance. Nevertheless, it still looks like the first widespread near to sub-freezing temperatures of the Fall with lows expected to range from 30-32F across most inland areas away from the coast and upper 30s to lower 40s near and along the coast. Therefore, have issued a Freeze Watch for locations along and east of I-95 but away from the coast in VA as well as Northampton and Hertford Counties in NE NC for Friday night into early Saturday morning. NBM probabilities for subfreezing temperatures were quite high over this region, however (as previously noted), given that NBM is on the cool side of guidance, temperatures may still be a bit too high. In any case, widespread frost is expected which may bring the end to the growing season for many inland locations. Lows may be even cooler Saturday night into Sunday morning with upper 20s to lower 30s inland. As such, an additional round of Freeze Watches or Warnings may be needed for Saturday night into Sunday morning for counties that don't drop below freezing Saturday morning (and are expected to drop below freezing by Sunday morning). Otherwise, breezy conditions are also expected Friday and Saturday as CAA brings NW winds gusting to 20-25 mph inland and 25-30 mph along the coast. These winds will allow for temperatures to feel even colder with wind chills in the mid-upper 20s for many inland areas (mid 30s along the coast) Friday night into Saturday morning as well as Saturday night into Sunday morning. Outside of the much cooler weather, dry weather is expected from Saturday through next week.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

As of 655 PM EST Thursday...

Mainly VFR in VA/NC through the 00z TAF period, with CIGs falling to MVFR at SBY. Showers will move offshore by this evening with SCT-BKN sky cover continuing through the night. As low pressure deepens offshore, wrap around moisture will likely result in BKN MVFR CIGs at SBY starting late tonight and continuing for the remainder of the 00z TAF period. Elsewhere, expect SCT-BKN clouds between 4000-8000 ft. Winds become W and eventually NW tonight-Friday with gusts to 20 kt expected.

Outlook: VFR conditions are favored from Saturday into next week with continued gusty NW winds through the weekend.

MARINE

As of 230 PM EST Thursday...

Key Messages:

- Small Craft Advisories are in effect for the Chesapeake Bay, lower James River, and coastal waters north of the VA/NC border beginning late tonight through tomorrow afternoon/evening.

- A prolonged period of SCA conditions is expected through much of the weekend, with the strongest winds likely occuring on Saturday.

This afternoon, a cold front is situated just west of the waters with SW winds currently ranging from 10 to 15 knots. Seas are generally running around 2 to 3 feet and waves in the Bay around 1 foot. The front crosses the waters later this evening, with winds becoming NW and increasing in its wake due to strong CAA and a tightening pressure gradient. NW winds increase to 15 to 25 knots with gusts of 25 to 30 knots late tonight into early Friday morning. In addition, seas will build to 4 to 5 feet (6+ feet well offshore) and 3 to 4 feet in the Chesapeake Bay. Small Craft Advisories are in effect for the Chesapeake Bay beginning at 10 PM EST and for the coastal waters beginning at 1 AM EST Friday. SCAs are also in effect for the lower James River into Friday afternoon. Winds likely diminish somewhat Friday afternoon and evening as the initial surge weakens.

A secondary surge of stronger NW winds is expected Friday night into Saturday as a secondary, dry cold front crosses the waters. Widespread SCA conditions are expected, with NW winds of 20 to 25 knots and gusts around 30 knots. The strongest winds are expected Saturday morning into Saturday evening. An isolated gust to 35 knots is possible out around 60 nm, but Gale wind gust probabilities continue to decrease. The pressure gradient remains compressed into Sunday, with SCA conditions likely to linger through Sunday morning and potentially into the afternoon across the Chesapeake Bay before winds gradually diminish. Existing SCAs will likely need to be extended with later forecast packages to account for the second surge of stronger winds. Seas build to 4 to 6 feet nearshore and 6 to 8 feet offshore, with waves in the Bay averaging 2 to 4 feet. Calmer conditions are expected for later Sunday into early next week as high pressure builds over the region.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...Freeze Watch from late Friday night through Saturday morning for NCZ012-013. VA...Freeze Watch from late Friday night through Saturday morning for VAZ076-079>083-087>090-092-512>522. MARINE...Small Craft Advisory from 10 PM this evening to 7 PM EST Friday for ANZ630>632-634. Small Craft Advisory from 10 PM this evening to 10 AM EST Friday for ANZ639. Small Craft Advisory from 1 AM to 7 PM EST Friday for ANZ650- 652-654-656.