Subj : Severe Potential IN/KY/OH/WV/VA/PA/MD To : All From : Mike Powell Date : Mon Apr 14 2025 14:40:24 MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN ACUS11 KWNS 141818 SWOMCD SPC MCD 141818=20 VAZ000-MDZ000-WVZ000-PAZ000-OHZ000-KYZ000-INZ000-142015- Mesoscale Discussion 0448 NWS Storm Prediction Center Norman OK 0118 PM CDT Mon Apr 14 2025 Areas affected...Portions of the Middle/Upper Ohio River Valley to the Central Appalachians. Concerning...Severe potential...Watch likely=20 Valid 141818Z - 142015Z Probability of Watch Issuance...80 percent SUMMARY...Severe storms capable of producing large hail and damaging wind gusts will spread eastward through the afternoon into the evening. A watch will likely be issued within an hour or two for parts of the area. DISCUSSION...Initial thunderstorms are developing across southern IN this afternoon, generally focused along/ahead of an eastward-moving cold front. Ahead of this activity, continued diurnal heating amid increasing boundary-layer moisture (middle/upper 50s to lower 60s dewpoints) will continue to erode inhibition and support additional storm development. Steep midlevel lapse rates (sampled by earlier 12Z soundings) atop the destabilizing boundary layer will yield around 1500 J/kg MLCAPE, favoring a gradual increase in storm intensity through the afternoon. As 60+ kt of midlevel flow (sampled by upstream VWP data) overspreads the warm sector, very long/mostly straight hodographs (60-70 kt of effective shear) will promote splitting supercell structures, posing a risk of large hail and damaging wind gusts. Despite the expectation for an initially semi-discrete mode, strong outflow amid the splitting storm structures will favor gradual upscale growth into small lines and clusters with eastward extent -- with an associated increasing severe-wind risk. A watch will likely be issued for parts of the area within an hour or two. ...Weinman/Mosier.. 04/14/2025 ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...MRX...JKL...ILN... LMK... LAT...LON 38248556 38918470 39248402 39638285 40028068 39977973 39747915 39357876 38847859 38237864 37707920 37408001 37228138 37038395 37138489 37338555 37818577 38248556=20 MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN *** AWUS01 KWNH 141916 FFGMPD MDZ000-VAZ000-WVZ000-OHZ000-KYZ000-INZ000-150115- Mesoscale Precipitation Discussion 0139 NWS Weather Prediction Center College Park MD 316 PM EDT Mon Apr 14 2025 Areas affected...West Virginia, southern Ohio, northern/eastern Kentucky Concerning...Heavy rainfall...Flash flooding possible Valid 141915Z - 150115Z Summary...Scattered convection will produce areas/spots of 1 inch/hr rain rates at time, posing a risk of isolated flash flooding through 04Z this evening. Discussion...Over the past hour, scattered convection has developed from Bloomington to near Cincinnati. These cells were on the northeastern extent of an axis of 1000-2000 J/kg SBCAPE and were also along and just ahead of a surface front that was making steady eastward progress across the Ohio Valley. Convection was already oriented parallel to steering flow aloft - with localized training noted just south of Cincinnati already prompting MRMS/local radar estimates of 0.75 inch/hr rain rates in a few spots. Through the afternoon, convection will mature and increase in coverage, with supercellular wind profiles, moderate instability, and continued orientation parallel to mean flow aloft supporting localized areas of training. Occasional areas of 1 inch/hr rain rates are expected, which could fall over sensitive areas and prompt isolated flash flooding. Areawide FFGs are in the 1-1.5 inch/hr range and should be approached on an isolated basis where the most focused/pronounced training could occur. Convection should move quickly eastward over the discussion area due to fast flow aloft, with flash flood potential increasing over West Virginia from the 22Z/5pm timeframe onward. CAMs also indicate potential for convective development southwestward along the front (across Kentucky) that could produce brief/spotty flash flooding if localized convective training can materialize. Cook ATTN...WFO...ILN...IND...JKL...LMK...LWX...PBZ...RLX...RNK... ATTN...RFC...MARFC...OHRFC...NWC... LAT...LON 39798072 39207927 38027965 37388120 37008451=20 37258573 37998577 39388566 39748379=20 $$ --- SBBSecho 3.20-Linux * Origin: ILink: CCO - capitolcityonline.net (454:3/105) .