textproduct: NWS Wilmington

WHAT HAS CHANGED

All sections updated with little to no change in forecast thinking.

KEY MESSAGES

-1)Heat will continue to build over the next several days. The heat index values will become increasingly dangerous after the midweek period.

DISCUSSION

KEY MESSAGE 1...Heat will continue to build over the next several days. The heat index values will become increasingly dangerous after the midweek period.

KEY MESSAGE 1 DESCRIPTION... Heat will continue to build over the next several days. The heat index values will become increasingly dangerous after the midweek period. And although no real thermal advection is noted Wednesday mixing is forecast to be a bit deeper for a few degrees of added heat during the afternoon hours. This is also forecast to allow inland dewpoints to fall a bit, but another Heat Advisory is anticipated. Higher dewpoints could pool along the immediate coast for HI values that flirt with warning criteria. Thursday through Saturday the ridge will flatten, which sometimes supports an abating of the heat. Not so this week as the increased flow in the low to mid levels actually leads to some weak and unwanted WAA. Temperatures will rapidly warm into the upper 90s after lows within a degree of 80 each day. Heat index values solidly in advisory criteria all 3 days and once again there may be a coastal vs inland gradient in dewpoints, highest east. A few coastal counties could meet Extreme Heat Warning thresholds (HI of 110 or above). Thereafter the massive ridging aloft moves west and we wind up in NW flow. This will curb the heat though perhaps not all the way down to climo. The vort-laden NW flow will also leave the area prone to rounds of thunderstorms that will likely be on the strong side as NW flow storms often organize a cold pool.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

Thunderstorm coverage should once again be high enough that all terminals deserve a PROB30 group through about sundown. Guidance isn't very aggressive in its fog depiction though the relative max of current radar returns in the Grand Strand region may raise the prospects of lowered vsbys towards daybreak.

Extended Forecast...Generally VFR. Low potential for flight restrictions from fog or low ceilings each morning. Threat for periodic flight restrictions from daily afternoon and evening showers/thunderstorms through Sat. More numerous thunderstorms possible Sunday.

MARINE

The Piedmont trough will remain in place through most of the period and be the dominant wind-maker as the Bermuda High is displaced eastward. Winds remain solidly SW save for the seabreeze acceleration. A slight westward jog off the offshore high will increase winds Thursday into Friday and less so Saturday. A brief window of advisory-worthy 6 ft seas is tough to rule out.

ILM WATCHES/WARNINGS/ADVISORIES

NC...Heat Advisory until 8 PM EDT this evening for NCZ087-096-099- 105>110. Beach Hazards Statement until 8 PM EDT this evening for NCZ106- 108. SC...Heat Advisory until 8 PM EDT this evening for SCZ017-023-024- 032-033-039-054>056-058-059. Beach Hazards Statement until 8 PM EDT this evening for SCZ054- 056. MARINE...None.