721 FXUS61 KILN 101800 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 200 PM EDT Wed Oct 10 2018 .SYNOPSIS... Showers with a few thunderstorms will develop in the warm and increasingly humid airmass today. Chances for showers and thunderstorms will increase tonight with the passage of a strong cold front. After the front pushes through, a breezy, dry, and cool period will commence for the end of the week. Cool weather will continue this weekend with showers possible Sunday into Monday with the approach of the next front. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Negatively tilted shortwave ejects northeast from the northern Plains across the upper MS Vly today and the Great Lakes tonight. Moisture will increase in the moist southerly flow ahead of this feature. Favorable isentropic lift/WAA showers developing across Kentucky and Indiana will pivot north offering scattered/numerous showers into the afternoon hours. Marginal instability develops late this aftn ahead of a prefrontal trof axis, so will continue to mention a chance of thunder. SPC has placed the entire forecast area in a marginal risk for severe storms. This would be associated with the line of convection within the prefrontal trof this afternoon into this evening. The main threat will be damaging winds. On the warm side of the system expect highs to range from the mid 70s west to near 80 east. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Negatively tilted s/w to pivot from the upper MS Vly into the Great Lakes tonight. Associated strong cold front to push east through the area between 03Z and 09Z. Favorable deep layer shear will exist but instby will be marginal and weakening. Although the deep-layer shear is favorable for organized storms, midlevel lapse rates are not impressive and with upper level support weakening and with diminishing instby do not expect widespread chance for severe weather. Therefore, have limited any mention of strong to severe storms to isold in the HWO. The main threat will be strong to damaging winds. Pcpn chances will begin to end from the west late tonight as the front pushes off to the east. Tonight lows will range from the lower 50s west to the lower/middle 60s east. In the wake of this front all pcpn will end early Thursday with west-northwest winds at 15 to 20 mph ushering a cooler airmass into the region. Temperatures will be a little below normal with highs on Thursday ranging from the upper 50s northwest to the upper 60s southeast. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... A wavy upper air pattern will result in rounds of unsettled weather, while lowering geopotential heights point to cooler temperatures. For Thursday night and Friday, much cooler and drier air will be circulating around high pressure centered to the west. Along with below normal temperatures, no precip is expected. A potent mid level short wave embedded in a westerly flow will bring a chance of showers Friday night. Frost may develop early Saturday morning behind the departing short wave, with dry weather persisting through the rest of the day. A cold front arriving from the west will bring a chance of showers Saturday night through Monday. There is some uncertainty with respect to timing and we may see a later time of arrival for this system. High pressure and dry weather may allow frost formation again on Tuesday morning. Temperatures flipping below normal will feature highs in the 50s and 60s, with lows falling to the 30s and 40s. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Surface low pressure and its upper level energy will move northeast across the western Great Lakes into southeast Canada tonight. Warm, moist ascent well ahead of an attendant cold front was producing some light showers across the region this afternoon. Models push this activity to the north while showers and a few embedded thunderstorms develop within a prefrontal covergent axis moving in from the west. Some MVFR conditions are likely with the showers and embedded thunderstorms as they move east/northeast across our area. Predominate ceilings will lower between 1000 and 2000 feet behind frontal passage while the precipitation exits off to the east. Southerly winds, locally gusty, will shift to the west/northwest with frontal passage. On Thursday, subsidence in the wake of the weather system should gradually scour MVFR ceilings out between 15Z and 18Z. Northwest winds between 10 and 15 knots will gusts up to 20 knots. OUTLOOK...MVFR ceilings and visibilities possible Friday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...Hickman/AR NEAR TERM...Hickman/AR SHORT TERM...AR LONG TERM...Coniglio AVIATION...Hickman