737 FXUS61 KILN 230555 AFDILN AREA FORECAST DISCUSSION National Weather Service Wilmington OH 155 AM EDT Fri Apr 23 2021 .SYNOPSIS... High pressure reaching Kentucky will provide dry and chilly weather tonight. Somewhat warmer temperatures and increasing clouds area forecast for Friday as the high moves east. Low pressure traveling from the southwest will bring widespread showers on Saturday. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Clear skies will prevail until higher clouds stream in from the west overnight. Temperatures will bottom out before the clouds enter and hold steady through daybreak, possibly rising slightly in the southwestern CWA. Patchy to widespread frost is expected across the entire CWA through daybreak. Lows will be fairly uniform as the drop in the 30-33 degree range. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/... Friday will feature dry weather as high pressure advances toward the Atlantic Coast. Increasing mid level clouds will be observed as moisture moves in ahead of the next low pressure system. While temperatures stay below normal, highs around 60 will feel warmer compared to the last two days. Conditions change Friday night as surface low pressure driven by a deepening upper trough travels northeast toward Kentucky. As moisture and lift produce thickening clouds, showers may begin in western locations by 2 am Saturday, with showers likely west and a chance of showers in the east by 6 am. Warmer lows in the 40s will result in all liquid precip. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Mid level trough/shortwave to push through the area Saturday, bringing rain overspreading the mid Ohio Valley from the south central plains. The trough is fairly shallow and quick moving, with only marginal instability remaining further south into the southern Ohio Valley and TN Valley, closer to the passage of the surface low. So not expecting thunder, but rainfall totals near 0.5-0.75" possible near/south of the Ohio river. With clouds and rain, temperatures still below normal in the upper 50s. With the cold front associated with this system passing through Saturday evening/overnight, slow clearing of clouds through the day on Sunday, but some weak cold air advection will keep some diurnal CU through the day. With winds weakening as high pressure settles in Sunday night and clearing skies, some frost potential especially in areas near and east of Delaware/Columbus/Chillicothe/Portsmouth Sunday night/Monday morning. Still not confident enough about surface winds and extent of clearing, however. Further west, the beginning of warm air advection works in by Monday morning as the center of the surface high shifts east. Into the workweek, a more significant warming trend, with above normal temperatures into the 70s on Monday and near 80 on Tuesday. An advancing shortwave and frontal boundary will bring increasing clouds on Wednesday along with an increasing chance of precipitation Wednesday into Thursday. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... VFR conditions will prevail as southwest winds 8-10kt peak during the day and relax at night. High clouds will stream in from the west and lower through the day but still only bottom out in the 8-12kft range overnight. Any rain and/or cigs/vsbys dropping into the MVFR category will wait until daytime hours on Saturday. OUTLOOK...MVFR/IFR conditions possible Saturday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...Frost Advisory until 9 AM EDT this morning for OHZ026-034-035- 070-077-078. Freeze Warning until 9 AM EDT this morning for OHZ042>046- 051>056-060>065-071>074-079>082-088. KY...Frost Advisory until 9 AM EDT this morning for KYZ089>095. Freeze Warning until 9 AM EDT this morning for KYZ096>100. IN...Frost Advisory until 9 AM EDT this morning for INZ058-066- 073>075-080. Freeze Warning until 9 AM EDT this morning for INZ050-059. && $$ SYNOPSIS...Coniglio NEAR TERM...Franks SHORT TERM...Coniglio LONG TERM...JDR AVIATION...Franks