textproduct: NWS Wilmington

WHAT HAS CHANGED

Aviation section updated for the 12Z TAF issuance.

As of 3 AM EDT... A new Coastal Flood Advisory will be issued for high tide tonight for downtown ILM/lower Cape Fear River. A Small Craft Advisory was issued for all coastal waters for tonight. The TAF discussion updated for 06Z issuance.

KEY MESSAGES

1) Heat Advisory in effect all areas today.

2) Strong to severe thunderstorms possible later this afternoon and evening.

DISCUSSION

KEY MESSAGE 1...Heat Advisory in effect all areas today.

KEY MESSAGE 1 DESCRIPTION... High temperatures of 93-96 away from the coast coupled with dewpoints in the 70s will result in heat index values generally between 103-107. The Heat Advisory has been expanded to the remaining parts of the forecast area. One potential challenge would be an increase in convective debris cloudiness spilling across the area from the NW/N. If it becomes extensive then this would impede afternoon temperatures and the heat index.

KEY MESSAGE 2...Strong to severe thunderstorms possible later this afternoon and evening.

KEY MESSAGE 2 DESCRIPTION... The chances for strong to severe thunderstorms will increase later today. Questions remain as to whether or not the lead area of storms approaching will hold together or head more southward (just west of the forecast area). This could potentially set the stage for another round of development during the evening especially north of the forecast area that would build southward. The question regarding the second round relates to if just the northeast part of the forecast area would receive storms or a larger portion.

AVIATION /10Z TUESDAY THROUGH SATURDAY/

Patchy fog across the region this morning will decrease in coverage shortly after sunrise. VFR expected for much of the day. Southwest winds increase this afternoon as the pressure gradient tightens ahead of a cold front. Uncertainty in the development and progression of convection continues for this afternoon. Recent continuity in hi-res models has prompted an upgrade to TEMPO where convection appears more likely. Debris clouds and upstream convection should allow for better confidence with the next routine issuance.

Extended Forecast... VFR conditions should dominate Wednesday through Saturday.

MARINE

Today through Saturday...An area of low pressure moving toward the Northeast U.S. today will allow SWly winds to increase as the pressure gradient tightens ahead of an approaching front. Plan to raise a Small Craft Advisory with this package, especially since GEFS >20 knot probabilities are in the 90-100% range beginning by early this evening through early Wednesday morning. Afterward, in the wake of the front offshore flow weakens across the waters during Wednesday. This boundary could waffle back to the north Wednesday night, then offshore again Thursday with a brief period of offshore flow before becoming light/variable Thursday night into Friday. Possible Sly flow becoming established by Saturday but confidence is low at this time. Seas will be highest tonight into early Wednesday, then another bump in seas Wednesday night early Thursday. Otherwise, 3 ft or less through the rest of the period. Regarding showers/t- storms: Isolated/widely scattered very early this morning associated with old outflow, then scattered to numerous tonight with the approaching front. Unsettled weather will return by Wed night, followed by scattered storms across the waters Saturday.

ILM WATCHES/WARNINGS/ADVISORIES

NC...Heat Advisory from noon today to 8 PM EDT this evening for NCZ087-096-099-105>110. Beach Hazards Statement through this evening for NCZ106-108. Coastal Flood Advisory from 8 PM this evening to midnight EDT tonight for NCZ107. SC...Heat Advisory from noon today to 8 PM EDT this evening for SCZ017-023-024-032-033-039-054>056-058-059. Beach Hazards Statement through this evening for SCZ054-056. MARINE...Small Craft Advisory from 5 PM this afternoon to 8 AM EDT Wednesday for AMZ250-252-254-256.