textproduct: NWS Wilmington

WHAT HAS CHANGED

Small Craft Advisory hoisted for all zones 4AM-10AM Wednesday.

KEY MESSAGES

1) Expect breezy and mild weather on Wednesday with hazardous conditions for small craft.

2)Minor drought releif late this week.

DISCUSSION

KEY MESSAGE 1...Expect breezy and mild weather on Wednesday with hazardous conditions for small craft.

KEY MESSAGE 1 DESCRIPTION... As high pressure shifts offshore of the Southeast US tonight, a relatively strong low pressure system will shift through the upper Great Lakes, tightening the pressure gradient once again. This will result in light winds this evening gradually increasing after midnight. Southwest winds will become breezy early on Wednesday, with sustained speeds reaching 15-20mph and gusts as high as 30 mph or so from midday through the afternoon. High temps in the low 60s will ensure it does not feel as chilly as on Monday. Refer to the marine discussion below for more details on the anticipated hazardous conditions for small craft.

KEY MESSAGE 2...Minor drought releif late this week.

KEY MESSAGE 2 DESCRIPTION...A sheared shortwave embedded within broad, low amplitude trough in the east crosses the region on Friday. Guidance is trending quicker with the surface front being driven by this feature, which now appears to clear landmass by later Friday (see below where coastal waters could take longer). Regarding rainfall, there is a good fetch off of the Gulf which should lead to very high, near certain rain chances late Thursday into Friday, the sense of exact timing likely refined in future forecasts. Conversely the forcing for ascent is weak due to the weakness of the mid level vort as well as there only being weak baroclinicity with the surface boundary itself. And while QPF can be a little tricky 3-4 days out it does appear that most places should average one half to three quarters of an inch of rainfall. Thunder could obviously lead to locally higher amounts but instability is quite lacking.

AVIATION /18Z TUESDAY THROUGH SATURDAY/

High confidence exists for VFR through the period as dry air and subsidence keep skies free of low clouds or fog. High clouds will increase in coverage later today and increase in thickness tonight as low pressure passes well to the north. Gusty southwest winds will be the primary threat to aviation on Wednesday, with LLWS just below the 30kt criteria tonight as winds increase aloft.

Extended Forecast...VFR until Thursday, when flight restrictions return due to increasing rain chances.

MARINE

Through Wednesday... High pressure will shift offshore of the Southeast US tonight, with WNW winds this afternoon backing to SW this evening. Light winds will permit 1-3 ft seas into early tonight. SW flow will increase overnight, with speeds nearing Small Craft Advisory criteria by the end of the night. Sustained winds of 20-25 kts and gusts of 25-30 kts (with some 30-34kt gusts possible near the 20nmi boundary southeast and east of Cape Fear) will continue through Wednesday and into Wednesday night. Seas will respond to the increasing winds by rising to 4-7 ft by mid-afternoon Wednesday before gradually subsiding from the evening onward. Seas will be primarily driven by wind waves with a weak 1-2 ft ENE swell every 12 seconds also contributing to the wave spectrum.

Wednesday night through Sunday... The period starts with unsettled weather likely needed SCA as the approach of a frontal boundary tightens the gradient. SW winds gusting to criteria and a few 6 ft seas will be found over mainly northern three zones. Thursday night into Friday the need for headlines becomes a bit muddled. The boundary drops closer, easing the gradient near the coast, but it's tough to rule out whether a few advisory-worthy 6 ft waves will persist as the weak easterly swell energy won't be much of a factor. Not to mention some guidance is a little quicker in pushing the front through and light NE winds should be spreading south gradually across the forecast zones. Best forecast at this time is that headlines will be able to be dropped Friday but may continue to highlight its possibility in HWO. Weak low pressure developing on the well offshore boundary Saturday could tighten the gradient and increase wind waves only slightly as what little swell energy was present decays.

ILM WATCHES/WARNINGS/ADVISORIES

NC...None. SC...None. MARINE...Small Craft Advisory from 4 AM to 10 PM EST Wednesday for AMZ250-252-254-256.