Area Forecast Discussion
Issued by NWS Wilmington, OH

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KILN 231749 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 149 PM EDT Mon Apr 23 2018 .SYNOPSIS... An upper level low pressure system will push slowly east across the Tennessee and Ohio Valleys today through Tuesday, bringing rain showers to the region. High pressure and drier conditions will return for mid week. Cooler than normal high temperatures will persist through the end of the week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Easterly flow at the surface is evaporating the northern edge of the precipitation shield. Mesoscale models are still indicating that the rain band will gradually overcome the drier air at low levels and will reach central Ohio by the end of the afternoon. Upped PoPs in the sw to 100, and increased Pops across all the southern half to categorical. Left northern areas as likely. Coolest highs are still expected in Cinci Tri-State where they will be around 60. Highs will increase as you head northeast towards Central Ohio where the highs will be in the mid to upper 60s. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... The upper level low will drift slowly eastward across the Tennessee Valley tonight through Tuesday and weaken somewhat as it does. This will keep the chance of showers going into Tuesday with the highest pops slowly shifting east across our area tonight into Tuesday. Instability looks to be marginal at best across our area, generally remaining to our south, so think thunder chances will be rather low. Lows tonight will be in the upper 40s to lower 50s with highs on Tuesday only in the mid to upper 50s. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... Tuesday night a vertically stacked upper level low will be located over the Kentucky/ Tennessee border with another potent upper level disturbance located over Wisconsin. This secondary wave will dive southeast helping to eject the upper level low off quickly to the northeast Wednesday. There are some slight differences in the upper level flow depicted Wednesday with the ECMWF keeping the upper level low slightly deeper than the GFS and CMC. This means that for Wednesday afternoon the GFS, NAM, and CMC all only show exiting precipitation across the area, while the ECMWF is slightly more bullish. For now have just trended the precipitation to a slightly quicker exit for Wednesday. Wednesday evening an upper level disturbance over Wisconsin will move east pushing a surface cold front through the area. By this time enough dry air has moved into the region which will keep the area dry. There remains a lot of slight model differences beyond this period that still have to be resolved, but the general idea is for another upper level disturbance to push through the area Friday afternoon into evening allowing another cold front to pass through. For the most part Saturday through Monday looks dry with temperatures moving closer to normal. Confidence with this remains low though as multiple model to model and run to run consistencies are lacking. The first discrepancy exists Thursday afternoon as the ECMWF deepens the upper level low over Pennsylvania, while the CMC and GFS are more progressive. Since the GFS and CMC are more progressive they actually are stronger with the southern stream of PV keeping precipitation to the south (ECMWF has precip Thursday across our northeast). For now the ECMWF appears to be the outlier here, so have kept the area dry for Friday. For Saturday into Sunday another upper level trough axis will move across the area with the ECMWF and GFS now being the progressive models and the CMC wrapping up an upper level disturbance across Tennessee (544 dam heights). Given all the above, have kept the forecast dry, but this could easily change given the complex flow. && .AVIATION /18Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
H5 low, which is driving the rain band located across the srn tafs, will move slowly east through the taf period. Consensus of the models, is to pivot the rain band north on through the Scioto Valley, while weakening the wrn edge around the Ohio/Indiana border. This all occurs thru 00Z. Ceilings will gradually lower to MVFR by 00Z, except CMH/LCK where drier low levels should keep ceilings VFR. Showers will become more scattered overnight, but ceilings will hold steady. By 12Z, another surge of showers is forecast to lift into the southern tafs, lowering ceilings to IFR. This band will try to lift north through 18Z. For the extended taf at CVG, the Tuesday morning rain showers will lift north of CVG, leaving VCSH and allowing ceilings to lift to MVFR. OUTLOOK...MVFR ceilings will be possible through Wednesday.
-- End Changed Discussion --
&& .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...JGL/Sites NEAR TERM...Sites SHORT TERM...JGL LONG TERM...Haines AVIATION...Sites is the U.S. government's official web portal to all federal, state and local government web resources and services.