textproduct: Wilmington

WHAT HAS CHANGED

No significant changes.

KEY MESSAGES

KEY MESSAGE 1) Above normal temperatures will occur through the weekend, despite a weak cold front moving through this evening.

KEY MESSAGE 2) A better chance of showers and thunderstorms will occur along and behind a cold front that will move through Sunday afternoon into Sunday night. Temperatures will fall back closer to normal for early next week.

DISCUSSION

KEY MESSAGE 1) Warm southwesterly flow ahead of a cold front will continue this afternoon and offer above normal temperatures. The front will quickly push east this evening, with perhaps a late- developing storm from central Ohio south into northeast Kentucky. The 12Z convective-allowing models were mostly dry outside a narrow frontal band of convection on the 3km NAM. However, the latest (16Z) HRRR develops showers and storms along the front after 00Z, mostly along and southeast of Interstate 71. Will continue low PoPs in this area. While effective bulk shear is 30-35 knots, timing leads to a higher probability of elevated storms (per a 02Z simulated sounding in Pike County Ohio), with perhaps a remnant hail risk.

Behind the front, winds will become northeasterly. This, along with a healthy surface-based inversion could lead to some low clouds off Lake Erie across mostly central Ohio early Saturday morning. Where skies can clear, there are some signals of radiation fog developing.

Surface high pressure will move quickly to the east on Saturday with southerly flow returning by the afternoon. The southwesterly gradient will increase on Sunday ahead of a stronger cold front, so gusty winds and a very warm day is expected.

KEY MESSAGE 2) A stronger cold front will sweep through the middle Ohio Valley late Sunday into Sunday night. Guidance remains uncertain on timing of FROPA, ranging from early evening to near midnight. Moderate instability is expected ahead of the front during the afternoon hours... though a CAP may limit convection. A strong wind field and good forcing (as compared to today's front) will increase the risk of severe storms if they are able to take advantage of the instability ahead of the front. Will continue to monitor.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

Outside of a very small risk of a brief shower or storm late this afternoon through early this evening at CMH/LCK, VFR conditions are expected to start the TAF period. Late this evening the low-level winds will turn northerly, then northeasterly into the overnight hours. It appears we may see a stratus deck below 2,000 feet at the Columbus terminals. How far this deck extends back west toward DAY and ILN is uncertain. Where skies can remain clear, some radiation fog is possible. Guidance is focusing on the CVG and LUK terminals, so have included lower visibilities there.

Saturday should become VFR again as high pressure builds across the Great Lakes.

OUTLOOK...Wind gusts up to 30 kt possible Sunday. Thunderstorms possible Sunday afternoon and evening.

ILN WATCHES/WARNINGS/ADVISORIES

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