textproduct: Wilmington

WHAT HAS CHANGED

No significant changes to the previous forecast. A slight shift to quicken thunderstorm activity tomorrow.

KEY MESSAGES

1) A strong cold front will bring showers and thunderstorms to the area Saturday. Behind the front, a much cooler airmass will move into the region for early next week.

DISCUSSION

KEY MESSAGE 1) Upper ridge axis currently in eastern CWA will be east of us by nightfall. Southwest flow behind it will increase as the pressure gradient tightens down to the surface. A lobe of s/w energy will pass east through the region early Saturday, bringing with it an initial round of showers and thunderstorms that could be quicker and in eastern CWA by early afternoon. Trend is for this to be faster with each successive model run, and if this occurs it will significantly affect the severe threat/nature of any storms behind it. This initial line will tap into 1200-1500 sbcapes that are trailing weakening theta-e air. The best opportunity for stronger storms will be in the lower Scioto Valley and east of Maysville KY towards noon. Any severe threat will be damaging winds.

SPC slight risk is keying off of instability along the front with insolation lifting modestly moist air between the initial round and cold front. Wind profiles along/ahead of the front will be conducive to organized clusters, but I am seeing shear in a relatively unfavorable environment without insolation and instability to work with.

After what seems to be an initial round of storms beneath upper s/w lobe, there should be a lull in activity. Best severe threat will occur with the pre-frontal trough as the sfc front will only have a moderate amount of low level lift occurring in a worked-over boundary layer. A few models are hedging towards keeping storms along/s of the Ohio, but if the progressive nature of the upper s/w holds true, I wouldn't expect any additional severe threat for the second half of the day.

Assuming the initial pre-frontal line is east of the CWA by mid afternoon, there could be a rebound and second, weaker convective line. Mainly shallow/isolated showers popping along the cold front that will be acting as a weak trigger.

Strong CAA will develop behind the front later Saturday and continue through Monday, with highs on Sunday and Monday generally in the 50s and lows in the 30s. Sunday night will be the coldest night as temperatures drop into the low to mid 30s, leading to the potential for some frost/freeze conditions. Temperatures then warm back to the 60s/70s with overnight lows in the low 50s, closer to yet still above climatological min temps.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

A cold front will approach from the west tonight and push east across the area through Saturday afternoon. Showers and occasional thunderstorms found ahead of the front with strong sly flow will inhibit any trailing convection that might fire along the front in the afternoon. Lower cigs/vsbys will occur with any precip in the late morning/early afternoon but quickly recover.

More widespread showers and embedded thunderstorms will push across the region on Tuesday.

OUTLOOK...Thunderstorms likely Saturday morning and afternoon.

ILN WATCHES/WARNINGS/ADVISORIES

OH...None. KY...None. IN...None.