651 FXUS61 KILN 190506 AFDILN AREA FORECAST DISCUSSION National Weather Service Wilmington OH 106 AM EDT Tue Oct 19 2021 .SYNOPSIS... Dry weather will persist through Wednesday as high pressure moves slowly across the eastern United States. Low pressure tracking through the Great Lakes is forecast to bring the threat for showers and thunderstorms Wednesday night and Thursday. Mainly dry weather and cooler temperatures can be expected Friday and Saturday. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Expansive ridge of high pressure centered over Tennessee will continue to influence our weather. Clear skies expected overnight in the dry airmass. The clear skies and light winds will lead to the development of river valley fog overnight. Temperatures will be close to normal with lows mainly in the lower and middle 40s. A few locations, especially east and south, may dip briefly in the upper 30s. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... Surface ridge axis to shift east as broad mid level ridge begins to build into the area. Any river valley fog that develops overnight will improve quickly after sunrise. Dry weather will continue with only an increase in high level clouds. Warm advection will boost highs into the lower 70s Tuesday afternoon. Mid level ridge will continue to build into the area with southerly winds staying up around 5 mph at most locations. The exception again will be the protected valley locations where some fog development will be possible. Temperatures will be milder with lows in the mid and upper 40s. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... A surface high over the southern Appalachians will have southwest flow over the Ohio Valley through early Thursday, then a cold front crosses east through the region. Showers will be found ahead of the front and affect the bulk of the CWA northwest of the I-71 corridor through daybreak. In the afternoon, enough of a dynamic influence with an open h5 wave crossing east through Lake Erie will present itself with the surface front and spark some thunderstorms. Rain should end quickly in the afternoon from west to east as the upper low is very rapidly moving east and pushing the surface front along with it. Lingering showers will be possible later overnight and on Friday - generally cold-pool in nature and light. Models show differing h5 trough and s/w energy during the day Friday which brings timing and placement of showers in question. Temperatures will drop to the 40s Thurs and Fri night, with highs only topping out near 60 through the weekend. This is after a mild start for the mid-week period in the warm advection ahead of the front. Enough dry and cold air may necessitate frost headlines on Saturday night/Sunday morning but this is a bit far out to give it more than a cursory glance and nod in the AFD. Expecting lows near 40 which will naturally have lower values in a dry airmass. Readings over KY the night before and after look to be warmer in nature and bottom out in the mid 40s. Highs after Thursday will be pretty uniform near 60 degrees through Monday with a slight bump in the 60-65 range in Kentucky possible Sunday and Monday. Another shot of rain is expected Sunday and overnight as a convergent area and warm frontal processes develop along a w-e axis roughly running along the Ohio River. Upper level shortwave energy shows it dying out early Monday but that's too far in the future to put a definitive approach to the forecast. Just kept showers in from Sunday onward. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... Under high pressure and dry anticyclonic subsidence, VFR will persist except at LUK where BR and FG will reduce visibility this morning. Otherwise, SKC is forecast until cirrus move in this evening. Winds starting calm will rise to near 10 knots from the southwest this afternoon. OUTLOOK...MVFR ceilings and visibilities possible Thursday. MVFR ceilings possible Friday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...AR NEAR TERM...Hickman/AR SHORT TERM...AR LONG TERM...Franks AVIATION...Coniglio