textproduct: NWS Wilmington

WHAT HAS CHANGED

The next Heat Advisory is already in effect for July 4th, basically across the same areas of Southeast NC and Northeast SC that was outlined for July 3rd.

Aviation discussion updated with 00Z TAF Issuance.

KEY MESSAGES

1) Dangerous heat through early next week, with above normal temperatures and increased humidity.

DISCUSSION

KEY MESSAGE 1... Dangerous heat through early next week, with above normal temperatures and increased humidity.

A strong ridge centered over the Carolinas persists through the weekend as hot and steamy conditions beneath the ridge bring dangerous heat during a busy holiday weekend. Independence Day will be a virtual repeat of Friday with heat indices at or above 105 for northern portions of northeastern SC and most of southeastern NC. The existing Heat Advisory continues through this evening and another heat advisory (with the same footprint) has been issued for Saturday's holiday. Coastal zones and the southern tier of our forecast area remain the exceptions to the current heat advisories.

Ridging weakens and moves eastward on Sunday. High temperatures decrease by a couple of degrees, but dew points increase as the Bermuda high builds westward. Expect another round of heat indices around 105 degrees on Sunday afternoon. A mid level trough passes north of the area early next week which should dent the remnants of the ridge. The flow aloft becomes more zonal, with weak impulses in the westerly flow crossing the area. The weakened ridge would allow for a brief reprieve from the heat and open the door for daily rounds of showers and thunderstorms, especially as the trough axis moves through the Mid-Atlantic on Monday. ILM hangs on the western periphery of the ridge through next week which should maintain above normal temperatures, aided by weak westerly downslope flow. Afternoon storm chances should return next week, albeit with reduced coverage; development will favor the Piedmont trough.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/

High pressure at the surface and ridge aloft will maintain high confidence in VFR conditions over the next 24 hours. Small chance of shallow ground fog at coastal terminals Sat morning. Any impacts would likely be MVFR and confined to a short period around sunrise. Could observe FEW/SCT Cu, mainly along and west of the sea breeze during Sat. Sea breeze circulation dies out after sunset with winds veering to the SW AOB 4 kt for the remainder of the night. Winds generally SW around 5 kt daytime Sat morning. The coastal terminals will experience the development of the sea breeze around midday Sat with it progressing inland and reaching the inland terminals later in the aftn or early evening. the coastal terminals will see winds back to the SSE-S around 10 kt, and 5 to 9 kt after passing thru the inland terminals.

Extended Forecast... Generally VFR. Low potential for flight restrictions from fog/low ceilings starting Sunday morning. Heat will continue thru midweek with the threat for afternoon and evening tstorms Mon thru Wed.

MARINE

An afternoon sea breeze will dominate winds again on Saturday. On Sunday, Bermuda high pressure will build westward leading to a local gradient increase. Winds could gust to 20 knots on Sunday afternoon at the coast. Wind speeds increase a little more for early next week as the gradient tightens further, despite somewhat cooler inland temperatures. Seas 2-3 ft through the weekend start to increase late Sunday and into early next week, peaking around 3-4 feet on Tuesday in the extending SW fetch. The gradient weakens slightly on Wednesday, but the prolonged fetch keeps an elevated wind wave.

CLIMATE

High temperatures away from the coast are forecast to be near record levels late this week into early next week. Below are the daily records for July 3-7...

Saturday, July 4: KILM: 100 / 1993 KLBT: 101 / 1905 KCRE: 97 / 1942 KFLO: 102 / 1993

Sunday, July 5: KILM: 100 / 1902 KLBT: 103 / 2024 KCRE: 97 / 1996 KFLO: 103 / 2024

Monday, July 6: KILM: 100 / 1902 KLBT: 102 / 2024 KCRE: 101 / 1990 KFLO: 103 / 2024

Tuesday, July 7: KILM: 102 / 1977 KLBT: 102 / 2010 KCRE: 99 / 1953 KFLO: 104 / 1954

ILM WATCHES/WARNINGS/ADVISORIES

NC...Heat Advisory from noon to 8 PM EDT Saturday for NCZ087-096- 099-105-107-109. SC...Heat Advisory from noon to 8 PM EDT Saturday for SCZ017-024- 033-058-059. MARINE...None.