FXUS61 KILN 261045 AFDILN AREA FORECAST DISCUSSION National Weather Service Wilmington OH 645 AM EDT Fri Apr 26 2024 .SYNOPSIS... High pressure will shift to the east coast with a warm front lifting north through the area tonight. Precipitation chances will develop this afternoon, and increase tonight as the warm front moves through the region. Warm temperatures in store for Ohio Valley this weekend with mainly dry weather conditions. The threat for showers and thunderstorms returns Monday as a cold front approaches from the west. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Large area of surface high pressure centered over southeast Canada to shift off to the east coast today. High level clouds spilling over upstream mid/upper level ridge will be thickest over the southwest this morning. Where mostly clear skies will be observed over the northeast - temperatures will drop to lows in the mid and mid 30s. Frost development will be possible over the northeast and have continued frost advisory thru 9 AM. Upstream mid level ridge axis to build east across the area today with southwesterly flow developing on its back side. Moisture to increase with a band of showers (with possibly some embedded thunderstorms) moving into the area late in the afternoon and into the evening. Have limited pops to chance category thru the daylight hours. Temperatures to warm up today prior to thicker clouds and pcpn moving in during the late afternoon. Highs to range from the upper 60s northwest to the to upper 70s southeast. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... Band of showers and embedded thunderstorms to pivot northeast thru the area this evening in a region of favorable low level theta-e advection. The best coverage of pcpn will occur across west central Ohio this evening where more favorable forcing will be located. Behind this initial band of showers, a chance for rain will continue but coverage will be more limited. Mild lows generally in the upper 50s. In warm sector the favorable forcing shifts to the north with pcpn chances diminishing by Saturday afternoon. Temperatures warm around 10 degrees above normal with highs on Saturday in the upper 70s to around 80. Breezy conditions develop with south winds gusting up to 35 mph. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... H5 ridge will be fairly expansive across the eastern CONUS to start the period. Further ridge amplification/height rises will occur on Sunday, promoting warmer daytime highs in the low to mid 80s. Some weak instability will be present in this warm/humid air mass, but no synoptic forcing will really be present. However, will have to see if CAMs try to initialize any pcpn that would be diurnally driven. Ridge axis nudges eastward on Monday, with a shortwave trough working its way through the Midwest region. Clouds increase from the west throughout the day, with PoPs increasing substantially Monday night into Tuesday. QPF footprint not overly impressive with this system given the progressive nature of the shortwave trough and associated surface cold front. Weak cold front swings through early on Tuesday, moderating temperatures slightly. Most of the CWA will still observe daytime highs in the middle 70s to near 80. Weak ridging returns on Wednesday, keeping an unstable air mass in place across the region. This will provide at least a chance of PoPs across the Ohio Valley. Another shortwave trough will begin carving its way through the Upper Plains on Thursday, which will eventually work its way into our region. This will increase chances for showers/storms in our fa. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... High level clouds to continue to spill into the area today as a mid level ridge builds across the region. As the ridge axis shifts to the east moisture will increase late in the day into this evening. Clouds will thicken and lower while ceilings remain VFR this afternoon as the mid level ridge axis shifts east and the flow backs southwesterly. The favorable lift will result in a band of showers and embedded thunderstorms that pivots north thru the area late in the day into this evening. Have a mention of VCSH for this pcpn band with brief MVFR conditions possible in rain showers. A southwest low level jet of 40-45kt will result in a period of low level wind shear across the western TAF sites late tonight. East winds around 10 kts will become southeast at 10 to 15 kts this afternoon into this evening with gusts up to 20 to 25 kts overnight. OUTLOOK...Thunderstorms are possible Monday night into Tuesday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...Frost Advisory until 9 AM EDT this morning for OHZ026-034-035- 043>046-052>056-063>065-073-074. KY...None. IN...None. && $$ SYNOPSIS...AR NEAR TERM...AR SHORT TERM...AR LONG TERM...Clark AVIATION...AR