textproduct: Wilmington

WHAT HAS CHANGED

No significant changes.

KEY MESSAGES

1) A series of low pressure systems moving across the Great Lakes will bring chances for showers and thunderstorms late this afternoon into tonight and then again Wednesday night into Thursday.

DISCUSSION

KEY MESSAGE 1) A mid level short wave will pivot east northeast across the Great Lakes region this afternoon into tonight. As it does, a 25-35 knot 850 mb jet will shift east across Ohio through the evening ahead of a weak approaching cold front. The airmass across our area will be starting off fairly dry today but will begin to moisten up later this afternoon into this evening in the developing southwest flow. The better axis of instability will set up farther back to our northwest through this afternoon and then weaken as it works its way eastward into our area through the evening. As a result, expect an overall weakening trend in shower and thunderstorm activity as it spreads east into our area ahead of the front late this afternoon into this evening. Deep layer shear will be quite high though with 0-6km values in excess of 40 knots, so it will be tough to rule out a few strong to severe storms, primarily across our northwest late this afternoon into early evening. Damaging winds would be the primary threat.

Another mid level short wave will shift east across the southern Great Lakes Wednesday into Thursday. An associated surface low will develop and move across the southern Great Lakes Wednesday night as a warm front lifts north across our area, before a trailing cold front pushes east across the region later Wednesday night into Thursday. This will be accompanied by an anomalously strong low level jet with 850 mb winds increasing into the 60-70 knot range through Wednesday night. With strong moisture advection up into our area, PWs will increase to around 2 inches or so through the overnight hours.

Strong instability will develop off to our west during the day on Wednesday before beginning to shift east into our area into Wednesday night. By this time the better instabilities will be beginning to weaken but there should still be sufficient instability to allow for widespread showers and thunderstorms to drop southeast across our area through the night. Given the strong wind fields, some severe storms are likely. While damaging winds will be the primary threat, there will also be a lower end threat for large hail and tornadoes.

Showers and thunderstorms will continue into the day on Thursday across mainly our southeast ahead of the cold front, before tapering off through the afternoon.

The other concern will be locally heavy rainfall and flash flooding given the high PWs values Wednesday night into Thursday morning.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

Areas of MVFR to IFR river valley fog will dissipate through mid morning with VFR conditions then expected into this afternoon. Scattered showers and thunderstorms will develop late this afternoon into this evening ahead of an approaching cold front. Will cover this with a few hour prob30 for -shra at each of the TAF sites, although some thunder will also be possible during that time. Any pcpn should taper off later this evening with VFR conditions prevailing through the remainder of the TAF period.

OUTLOOK...Thunderstorms and gusty winds are expected at times Wednesday afternoon through Thursday afternoon.

ILN WATCHES/WARNINGS/ADVISORIES

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