textproduct: NWS Wilmington

WHAT HAS CHANGED

Aviation discussion updated.

KEY MESSAGES

1)Limited excessive rainfall potential today despite the deep tropical moisture.

DISCUSSION

KEY MESSAGE 1...Limited excessive rainfall potential today despite the deep tropical moisture.

KEY MESSAGE 1 DESCRIPTION... Deep moisture continues to linger in the region for much of today, despite precipitable water dropping a bit from near record levels earlier in the week. Forcing today is weak with limited low-level convergence and pockets of surface-based instability under flow aloft that is barely divergent. The lackluster environment will keep storm coverage limited. Expect to see a few weak storms fire on the sea breeze during early afternoon, but better coverage will hold off until the front starts pushing south.

Front will be crossing the area during peak heating and will have a pinned sea breeze to interact with. The front has the potential to kick off widespread showers and thunderstorms given the environment it is moving into. More robust convection will fire along the boundary and may end up starting where the sea breeze and the front first meet before expanding west. Heavy rain will be possible in any convection that develops along the front with potential for rainfall amounts of 1-3" under the strongest cells. However, storm motions and limited widespread heavy rainfall the last few days will help keep flooding potential very low. Front slowly pushes south of the forecast area late evening, ending any heavy rain threat.

AVIATION /09Z THURSDAY THROUGH MONDAY/

Mix of VFR/MVFR/IFR across the area this morning. Strong boundary layer winds coupled with high boundary layer moisture have resulted in low stratus instead of fog. Low ceilings will mix out after a little bit of post sunrise heating. Anticipate VFR at all sites 12Z-13Z.

Widespread VFR is likely to come to an end for most terminals mid to late afternoon through early evening as a cold front moves in from the north. Front is moving into a juicy air mass with plenty of surface based instability. Sea breeze will be present, albeit pinned to the coast and this could be where the first storms of the day get going. As the front moves south convective coverage will expand, but hard to say exactly when a shower or storm will reach a given terminal, hence the use of PROB30 groups.

Front pushes south of the area 00Z-04Z leaving north to northeast winds and VFR conditions at all sites.

Extended Forecast...A cold front will increase potential for MVFR/IFR Saturday. Potential for MVFR/IFR at times from scattered afternoon and evening storms during much of next week.

MARINE

Through Tonight... Enhanced southwest flow this morning will become westerly this afternoon as a front starts moving in from the north. The pinched gradient will initially keep speeds in the 15-20 kt range, but later today the gradient becomes less defined and speeds decrease. Westerly flow veers to north and then northeast once the front passes. Weak northerly surge follows with the development of northeast winds, but surge strength and duration are limited and conditions will remain below advisory thresholds. Seas 3-5 ft drop to 3-4 ft with the reduction in wind speeds later today. Following the passage of the front, 4 ft seas will become more widespread.

Friday night through Monday... Post-frontal winds will be onshore Friday night through the weekend as high pressure builds in from the north. Six foot waves will remain comfortably outside of the 20nm zones though winds may take a brief run at SCA wind gusts Saturday night. It is not until Monday that the center of the high moves off the coast enough for a more typical southerly component to return. The post-frontal winds will disrupt the SE flow that had been in place prior to the period keeping seas in the shorter period spectrum. Another front and high building from the north could bring a return of light onshore winds and keep wave periods in the wind wave realm towards the end of the period.

ILM WATCHES/WARNINGS/ADVISORIES

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