MESOSCALE DISCUSSION 0177
   NWS STORM PREDICTION CENTER NORMAN OK
   0356 PM CST MON FEB 28 2011
   
   AREAS AFFECTED...NRN ORE AND SRN WA CASCADES
   
   CONCERNING...HEAVY SNOW 
   
   VALID 282156Z - 010100Z
   
   HEAVY SNOWFALL RATES 1-2 INCHES PER HOUR WILL LIKELY CONTINUE
   THROUGH THE AFTERNOON ACROSS THE NRN ORE AND SRN WA CASCADES.
   
   AN UPPER LEVEL LOW OFF THE B.C. COAST IS FORECAST TO MOVE LITTLE
   THROUGH THE EVENING HOURS COINCIDENT WITH A STRONG UPPER JET
   REMAINING OVER THE PACIFIC NW.  AS SUCH...A FETCH OF HIGHER PW/S
   CHARACTERIZED BY EXCEEDING 1/2 INCH--SHOULD REMAIN FOCUSED OVER THE
   REGION AIDED BY 30-50 KT FLOW AT 1-2 KM ABOVE SEA LEVEL.
   
   LATEST SURFACE MAP SHOWS TEMPS IN THE UPPER 30S TO NEAR 40 DEG F IN
   THE WILLAMETTE VALLEY AND INTERIOR VALLEY LOCATIONS.  HOWEVER...SNOW
   LEVELS PER LATEST WEB CAM DATA INDICATE THAT HEAVIER SNOW
   ACCUMULATIONS ARE OCCURRING GENERALLY AOA 1000-1500 FT WHERE TEMPS
   ARE AOB FREEZING.  RECENT DETERMINISTIC MODEL GUIDANCE SUGGEST
   LIQUID EQUIVALENT PRECIPITATION RATES OF 0.10-0.20 INCH WILL
   CONTINUE...LEADING TO HEAVY SNOWFALL RATES ON THE WINDWARD SLOPES OF
   THE CASCADES.
   
   ..SMITH.. 02/28/2011
   
   
   ATTN...WFO...PDT...SEW...PQR...
   
   LAT...LON   44672242 46012210 46392175 46232144 45782141 45002158
               44332185 44362230 44672242