MESOSCALE DISCUSSION 1256
   NWS STORM PREDICTION CENTER NORMAN OK
   0826 PM CDT THU JUN 16 2011
   
   AREAS AFFECTED...SOUTHEAST WY/NORTHEAST CO AND NEB/SOUTHERN SD
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 484...
   
   VALID 170126Z - 170230Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 484
   CONTINUES.
   
   SEVERE TSTM WATCH 484 CONTINUES UNTIL 03Z...WITH CONTINUING
   POTENTIAL FOR DAMAGING WINDS/SEVERE HAIL. MONITORING FOR AN
   ADDITIONAL WATCH ACROSS EASTERN NEB/SOUTHEAST SD...AND CURRENT
   THINKING IS THAT A REPLACEMENT AND/OR WFO EXTENSION MAY BE NEEDED
   PRIOR TO 03Z FOR PORTIONS OF WW 484.
   
   A QUASI-LINEAR SEVERE MCS WILL CONTINUE TO STEADILY ADVANCE
   EAST-NORTHEASTWARD ACROSS THE NEB SANDHILLS THROUGH 02-03Z...WITH AN
   ASSOCIATED POTENTIAL FOR DAMAGING WINDS. WHILE THIS MCS WILL
   ENCOUNTER INCREASING LOW LEVEL CINH THE REMAINDER OF THE EVENING AS
   PER MODIFICATIONS TO THE 00Z NORTH PLATTE OBSERVED RAOB...THE
   EXISTING COLD POOL/BACKGROUND ASCENT SHOULD SUSTAIN A RELATIVELY
   ORGANIZED/VIGOROUS MCS OVER THE NEXT FEW HOURS. FARTHER
   NORTH...EPISODIC SEVERE HAIL WILL BE POSSIBLE INTO CENTRAL SD...BUT
   A LESSER DEGREE OF INSTABILITY/SHEAR SHOULD KEEP THE SEVERE THREAT
   MORE ISOLATED/MARGINAL WITH NORTHWARD EXTENT.
   
   FARTHER SOUTHWEST...ADDITIONAL UPSCALE MCS DEVELOPMENT IS LIKELY TO
   OCCUR ACROSS SOUTHWEST NEB THE REMAINDER OF THE EVENING. WITH
   TIME...THIS MAY BECOME THE MORE VIGOROUS MCS /AS COMPARED TO
   NORTHERN NEB/ GIVEN A MORE OPTIMAL COMBINATION OF VERTICAL SHEAR AND
   STRONGER EASTERLY INFLOW OF RELATIVELY MOIST/UNSTABLE AIR AS
   REFLECTED PER REGIONAL PROFILERS/WSR-88D VWPS.  
   
   OTHER STORMS CONTINUE TO INCREASE ALONG THE WY/CO FRONT RANGE THIS
   EVENING...ROUGHLY TIED TO THE LEADING EDGE OF FORCING/STRONGER FLOW
   ALOFT. BOUTS OF SEVERE HAIL/WINDS WILL BE POSSIBLE.
   
   ..GUYER.. 06/17/2011
   
   
   ATTN...WFO...FSD...OAX...ABR...GID...LBF...UNR...BOU...CYS...
   
   LAT...LON   40520520 41490509 42020407 42370211 43100155 44140028
               44070006 42899803 41799848 40910029 40750270 40240375
               40520520