MESOSCALE DISCUSSION 0068
   NWS STORM PREDICTION CENTER NORMAN OK
   0851 AM CST MON FEB 16 2015

   AREAS AFFECTED...SRN IL...SRN IND...SRN OH...KY...WV...WRN VA

   CONCERNING...HEAVY SNOW 

   VALID 161451Z - 162045Z

   SUMMARY...AREAS OF HEAVY SNOW WILL PERSIST ACROSS PARTS OF THE OH
   VALLEY AND DEVELOP EWD INTO THE CNTRL APPALACHIAN MTNS THIS MORNING.
   SNOWFALL RATES SHOULD REACH 1 TO 2 INCHES PER HOUR IN THE HEAVIER
   SNOW BANDS.

   DISCUSSION...THE LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LEVEL
   TROUGH OVER THE MID TO UPPER-MS VALLEY. THIS FEATURE WILL DIG SSEWD
   TODAY AS A 75 TO 90 KT MID-LEVEL JET OVERSPREADS THE OH VALLEY. IN
   RESPONSE...A 50 TO 70 KT LOW-LEVEL JET WILL MOVE QUICKLY ENEWD
   ACROSS THE TN VALLEY THIS MORNING. THE LEFT EXIT REGION OF THE
   LOW-LEVEL JET WILL OVERSPREAD THE MCD AREA LATE THIS MORNING AS
   ISENTROPIC LIFT MARKEDLY INCREASES. THE NAM FORECAST SOUNDING FOR
   JACKSON KY AT 18Z SHOWS A NEARLY SATURATED DENDRITIC GROWTH ZONE
   NEAR 500 MB WITH AN ISOTHERMAL PROFILE EXTENDING THROUGH A DEEP
   LAYER FROM BELOW THE DENDRITIC GROWTH ZONE TO NEAR 850 MB. THIS
   SHOULD BE FAVORABLE FOR THE DEVELOPMENT OF HEAVY SNOW. SFC TEMPS
   RANGE FROM AROUND 10 DEGREES F AT THE OH RIVER TO THE UPPER TEENS
   NEAR THE KY-TN STATE-LINE. THE PROFILE SHOULD RESULT IN HIGH SNOW TO
   LIQUID RATIOS MAKING HEAVY SNOWFALL LIKELY WITHIN THE HEAVIER BANDS.
   SNOWFALL RATES OF 1 TO 2 INCHES PER HOUR ARE EXPECTED OVER THE NEXT
   2 TO 4 HOURS FROM NEAR THE OH RIVER SWD TO THE KY-TN STATE-LINE.
   THIS HEAVY SNOWFALL SHOULD DEVELOP EWD INTO THE CNTRL APPALACHIAN
   MTNS BY LATE THIS MORNING AND PERSIST THROUGH THIS AFTERNOON.

   ..BROYLES/COHEN.. 02/16/2015


   ATTN...WFO...LWX...RNK...RLX...MRX...JKL...ILN...LMK...OHX...
   IND...PAH...

   LAT...LON   36648418 36668747 36688864 36768914 37118930 37798900
               38378789 39008544 39108316 38908085 38577962 37707965
               37008093 36648418