textproduct: Wilmington

WHAT HAS CHANGED

Adjusted probability for precipitation along the I-70 corridor into this evening.

KEY MESSAGES

1) Showers and thunderstorms into this evening with potential for some strong to severe storms.

2) Showers and some thunderstorms will move across the region Monday afternoon into Tuesday night with the potential of locally heavy rainfall.

3) Very warm temperatures will develop in the latter part of next week with some places possibly reaching 90.

DISCUSSION

KEY MESSAGE 1)

Mid level short wave over the eastern Great Lakes will continue to progress east. Lingering showers and storms over central Ohio that are occurring out ahead of this will continue pushing off to the east exiting the area.

Airmass is expected to recover with an axis of moderate instability developing as SBCAPE values around 2000 J/kg are expected at peak heating. Forcing is rather limited with outflow from this mornings convection acting as an axis of low level convergence. Some of the CAM solutions showing renewed development later in the afternoon into early evening across the I-70 corridor. Forecast soundings show DCAPE values of 800-900 J/KG with mid level lapse rates approaching 7 C/KM. These parameters suggest that the potential exists for a few of the stronger storms to produce strong to damaging winds. The most favored time looks to be between 4 pm and 10 pm. Weakening convection may continue into the late evening, but the potential for stronger storms will diminish. Areas near and south of the Ohio River may not see any storm development.

Moisture pooling along and south of the front, with PWATs of 1.5 to 1.7 inches. Most locations will observe 0.75 to 1.5 inches of rainfall. However, the potential exists for some training along the east-west corridor with HREF LPMM suggesting localized heavier amounts of 2 to 4 inches are possible. This could lead to localized flooding.

KEY MESSAGE 2)

A high amplitude narrow mid level ridge quickly develop on Sunday from the Ohio Valley into the Great Lakes. Weakness in the ridge there will be a shear axis that pushes into the region. The focus for shower and thunderstorm development Sunday will be over the southwest associated with a weak front that sags into the forecast area and stalls out. Moderate instability is expected to develop but shear will be very weak, so the threat for severe weather will be low.

A mid level short wave moving from the mid Mississippi Valley into the Great Lakes on Monday will push the ridge eastward. This short wave will make slow eastward progress on Tuesday keeping the threat for storms in the forecast.

Model solutions continue to advect favorable moisture into the region with PWAT values around 2 inches. This very moist airmass will move into western counties on Monday afternoon and then across the entire area Tuesday.

Showers and embedded storms are expected to develop and spread in from the southwest as a mid level short wave rides the backside of the ridge axis. Convective activity will diminish but may not completely dissipate on Monday night. There will be another increase in coverage Tuesday which will then taper off overnight Tuesday as the shortwave moves off to the east.

The very moist airmass will offer a favorable environment for high rainfall rates and the potential for locally heavy rainfall.

KEY MESSAGE 3)

A broad mid level ridge will expand from the southern Plains thru the Ohio Valley and into the Mid Atlantic for the latter part of the week. The humid airmass will remain in place and temperatures will rise and get very warm.

Forecast is probably a couple of degrees too warm from Thursday onwards given bias in the NBM, but nonetheless, there could be some locations that do reach 90 with apparent temperature in the mid to upper 90s.

AVIATION /14Z SATURDAY THROUGH WEDNESDAY/

Additional thunderstorms will develop across the I-70 corridor where moisture pools along a boundary from earlier convection. The best threat for storms will exist across KDAY, KCMH and KLCK. KCVG and KLUK may not observe any storms. Have prob30 mention in for this scattered storm development. A few of the storms may become strong to severe with the most favored time between 4 pm and 10 pm. Weakening convection may continue into the late evening, but the potential for stronger storms will diminish.

A VFR cloud deck will develop overnight. Additional storm development will be possible over the southern TAF sites Sunday afternoon and thus have included a mention in the 30 hour KCVG TAF site.

Southwest winds will gusts at or above 20 kts and then decrease toward 00Z and become light overnight.

OUTLOOK...Thunderstorms are possible, mainly during the afternoon and evening, each day from Sunday through Wednesday. MVFR ceilings and visibilities possible Monday night into Tuesday night.

ILN WATCHES/WARNINGS/ADVISORIES

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