textproduct: Wilmington

WHAT HAS CHANGED

Increasing potential for locally heavy rainfall south and east of I-71 Friday into Friday night.

KEY MESSAGES

1) Widespread showers and scattered thunderstorms will spread across the region Friday and continue into Friday night with the potential for locally heavy rain.

DISCUSSION

KEY MESSAGE 1) Active southwest flow aloft will bring a short wave across the region on Friday with a second one moving through Friday night into Saturday.

The initial impulse will cause showers and some embedded thunderstorms to spread across the region during the day. A warm front will lift to somewhere in the vicinity of the Ohio River by late afternoon/early evening. As the second short wave approaches, it will cause a surface low to lift northeast into the region, taking the warm front northwards as well. This will bring additional showers and thunderstorms through the area Friday night with the possibility of a brief lull late in the day Friday between the initial activity and this second push.

Precipitable water will be increasing again, getting to around 1.8 inches. There will be persistent moisture transport, particularly into the southeast part of the forecast area as an initially modest low level jet slowly strengthens Friday night. Warm cloud depth is forecast to range from 3.5 to 4 km. Given this environment, it is no surprise that a number of convective allowing models are showing corridors of heavier rainfall south and east of I-71. In terms of ensembles, the REFS is a bit more aggressive in both amounts and northward extent compared with the HEFS. So broadly, areas south/east of I-71 have the potential for flash flooding with the probabilities a bit higher in northeast Kentucky and south central Ohio in particular.

In addition, while surface instability will be limited, some will develop near and south of the warm front. There is a window late Friday afternoon into Friday evening where there could be sufficient overlap of lower end instability and shear to possibly produce a few rotating storms.

Showers and thunderstorms will continue into Saturday. The environment will be the same, but forcing will start getting shunted off to the east, taking the potential for heavier rainfall away from the area.

AVIATION /12Z THURSDAY THROUGH MONDAY/

MVFR ceilings at KLUK will lift early in the period. That improvement will gradually work its way southwards, reaching KILN after 18Z and KCVG/KLUK closer to 00Z. Lower level moisture will start pushing back north overnight causing ceilings to fall back to MVFR area wide before the end of the TAF period. Northeast winds will persist, but weaken after 00Z.

OUTLOOK...MVFR to IFR ceilings and visibilities are likely Friday into Saturday night with MVFR ceilings possibly lingering into Sunday.

ILN WATCHES/WARNINGS/ADVISORIES

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