textproduct: NWS Wilmington

SYNOPSIS

A cold front will move through tonight bringing in some chilly air through Thursday. A warmup to seasonable weather Friday will continue into a slightly mild Saturday. Arctic air arrives later Sunday ushering in the coldest air yet this season through Monday before moderation begins on Tuesday.

NEAR TERM /THROUGH THURSDAY/

Dry southwest flow will prevail through this evening ahead of a cold front trailing from a surface low crossing the Great Lakes. Wind gusts should develop early this afternoon as mixing deepens and taps into stronger winds aloft, with 25-30 kts expected at times. Gusts will diminish through the evening, but a continued breeze will keep temps from bottoming out, with lows mainly in the mid 30s. Fropa is expected 06-10Z, with sunny but still cool temps on Thursday, topping out a couple of degrees either side of 50.

SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/

Temperatures should be seasonable through the short term. There isn't much in the way of thermal advection and the pressure pattern will be quite weak so our seasonable afternoon especially is a function of insolation. Mid level flow will be zonal/westerly as one cutoff upper low in the NE lifts out while another starts to drop south out of Canada into MN. The latter disturbance will shape our upcoming weather changes in the long term.

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Friday's weak flow remains in place Saturday but atop this layer some WAA does kick in. This should allow coastal locales to hit 60 for the first time this month whereas inland locations may still struggle to do so. Sunday previously looked to be one last warm day ahead of the incoming Arctic cold front. Now the boundary appears a bit faster meaning not only not another mild day but the forecast high is tricky to nail down, literally hinging on the hour that this front comes through since thereafter temperatures will start to fall. And fall they will continue to do Sunday night as 850mb temperatures are driven down some 15 degrees C from roughly 6 to start the day to around -10 (or from 43 down to 14F). Forecast soundings Sunday night do show a few knots of wind preventing idealized radiational cooling. Though not idealized, it'll still be a pretty good setup. Guidance seems aware of this and has trended colder and now has places not right up against the ocean within a few degrees of 20. The proximity of the high will prevent deep mixing Monday, nullifying the WAA going on atop the boundary layer for a very unseasonably cold day where highs struggle to hit 40, possibly threatening the record low-high for CRE (though our other climate sites with a more robust database have much lower values). The latter part of the period will feature a warmup that will be very gradual at first but we may bounce back above climo on Wednesday.

AVIATION /00Z THURSDAY THROUGH MONDAY/

VFR through the 00Z TAF period. A low-level jet will continue to produce SW gusts up 15-20 kt as well as LLWS through early overnight, before a cold front crosses the area with winds veering to the W then NW averaging around 10 kt through the day Thursday.

Extended Outlook...Predominantly VFR through the rest of the period.

MARINE

Through Thursday...A Small Craft Advisory remains in effect into Thursday morning as low-level jetting will lead to wind gusts of 25- 30 kts this afternoon and overnight, and seas building to 6-7 ft. A cold front will move offshore in the predawn hours, and although low-level jet will weaken overnight, the post-frontal gradient should support 25 kt gusts into Thursday morning. Winds diminish to 15 kts by Thursday afternoon, although a few gusts to 20 kts may continue north of Cape Fear through the day.

Thursday night through Monday... Light winds to start the period as the pressure pattern will be rather poorly defined. A warm front lifting through on Friday will allow wind and seas to build later Friday but both stay well above any headline thresholds. Behind this boundary we go back to a sloppy pressure pattern Saturday so expect seas to abate slightly and the flow to become somewhat variable. On Sunday a powerful cold front will push through building winds and seas to advisory levels while wave faces steepen with the sharp veer in the wind.

ILM WATCHES/WARNINGS/ADVISORIES

NC...None. SC...None. MARINE...Small Craft Advisory until 7 AM EST Thursday for AMZ250-252- 254-256.