textproduct: NWS Wilmington

WHAT HAS CHANGED

Aviation discussion updated for 00Z TAFs.

KEY MESSAGES

1) A strong cold front on Monday will bring the chance of severe weather followed by freezing temperatures Tuesday night.

DISCUSSION

KEY MESSAGE 1...A strong cold front on Monday will bring the chance of severe weather followed by freezing temperatures Tuesday night.

Potent storm system over the Upper Midwest will track eastward with a deepening mid to upper trough becoming negatively tilted as it tracks from the Mississippi Valley on Mon. Very warm and moist air southerly flow ahead of a strong cold front with strong forcing from aloft will set the stage for possibility of severe storms. Temps will be well above normal again by Mon with dewpoint temps in the 60s. Pcp water levels will reach above 1.5 inches with a 50 to 60 kt LLJ. SPC had outlined our area in a 15 to 30% chance of severe weather on Day 4 which is quite high that far out. SPC also points out that the degree of low level shear and thus the risk for more organized convection/supercells is uncertain this far out in time. And, depending on the timing, it could coincide with max heating of the day. Stay alert for updates to this severe weather threat. We may also see potential for sea fog ahead of this front in warm moist air riding over the cooler shelf waters Sun night into Mon.

This strong cold front will move through late Mon with plenty of cold and dry air feeding into the Carolinas in deep NW flow. Temps up near 80 on Mon will drop into 40s and 30s inland by early Tues morning. The 850 temps will be down to -7 by Tues morning. The very cold air mass will remain in place through midweek with 50s for highs both Tues and Wed and overnight lows near or below freezing Tues night. There will most likely be freezing temps and possibility of frost Tues night.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/

Predominantly VFR through the 00Z TAF period. Winds become light/variable tonight but mainly out of the S/SW with a weak pressure gradient over the area. Chances of fog are low at the TAF sites for now, but will re-evaluate with future updates as I was close to including TEMPO groups at the Myrtles. Continued dry with light wind and mainly SKC daytime Saturday with sfc high pressure over the area.

Extended Forecast...VFR expected most of Saturday night. Flight restrictions become more likely by Sunday, due to increasing rain chances and associated cloud decks. These restrictions are expected to become even worse by Monday, as a strong cold front sweeps through the area, potentially bringing severe weather. VFR should return late Monday night, remaining that way through Wednesday.

MARINE

Through Saturday...Veering wind direction throughout the whole period, with SE winds becoming SW later tonight. Gradient tightens slightly for a bit, bringing the winds up to 10-12 kts throughout the overnight hours. This gradient loosens back up again by Saturday morning, decreasing the speeds back to around 5-8 kts. Veering continues, becoming northwesterly Saturday morning, and then onshore flow builds in again by the afternoon. Seas are on a downward trend throughout the whole period, starting from 2-4 ft, coming down to 1- 2 ft.

Saturday night through Tuesday Night...Onshore flow Sat night will become more SE to S through Sun into Sun night and increasing as a coastal trough pushes inland and north and cold front approaches the Carolinas. This onshore to southerly flow will kick seas up from less than 3 ft Sat night up above SCA thresholds by late Sun and will continue to increase further up until cold front passes through later on Mon. Gale force gusts are possible. Winds will veer around with the frontal passage late Mon with strong offshore flow pushing the greatest seas to the outer waters and producing steeper faces. Winds and seas should remain in SCA thresholds until some time late Tues into early Wed. Seas may reach as high as 7 to 9 ft Mon night.

ILM WATCHES/WARNINGS/ADVISORIES

NC...None. SC...None. MARINE...None.