textproduct: Wilmington

WHAT HAS CHANGED

No major changes.

KEY MESSAGES

1) Extreme heat through Thursday.

2) Hot and humid conditions will continue into the holiday weekend when the chance for showers and storms returns.

DISCUSSION

KEY MESSAGE 1)

Wednesday and Thursday are primed to be the hottest days of the week given the amplified H5 ridge heights and proximity of the high pressure as it stretches across the Ohio Valley. This will allow for daytime highs to reach the middle 90s both days, with dewpoints remaining in the middle 70s. This will result in max heat index values around 105 degrees or so. Some diurnal cu may develop, but clouds will be scattered enough to offer little relief from the sun.

KEY MESSAGE 2)

Model guidance continues to show the H5 ridge being suppressed by Friday. While the air mass itself will generally remain unchanged, the biggest question mark is coverage of shower/storm activity during the daytime. Storm mode would primarily be single-cell (pulse) type convection given the large amount of CAPE but very weak wind shear. CAMs will soon offer more insight on the coverage of storms for Friday, which will certainly play a role on max heat index values. Cannot rule out a potential extension of heat headlines into Friday if storm coverage appears very minimal given the relatively unchanged air mass.

Chances for convection do appear to be more likely on Saturday due to the dampening ridge, which will place the ILN CWA in closer proximity to upper level shortwaves. The synoptic pattern suggests that unsettled weather will continue through the rest of the weekend and perhaps into early next week as upper level flow becomes more meridional.

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

River valley fog expected to develop again tonight. Some vsby impacts are possible, mainly at KLUK and perhaps KLCK (lower confidence). Overland fog will be more limited but cannot be completely ruled out.

Some diurnal cu may develop today, but otherwise, no CIG impacts expected. Winds will subside tonight to around 5 kts or less, slightly increasing again during the daytime hours but remaining below 10 kts.

OUTLOOK...Thunderstorms are possible Friday through Sunday.

ILN WATCHES/WARNINGS/ADVISORIES

OH...Extreme Heat Warning until 8 PM EDT Thursday for OHZ026-034-035- 042>046-051>056-060>065-070>074-077>082-088. KY...Extreme Heat Warning until 8 PM EDT Thursday for KYZ089>100. IN...Extreme Heat Warning until 8 PM EDT Thursday for INZ050-058-059-066- 073>075-080.