SPC 0730Z Day 3 Outlook
DAY 3 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0230 AM CDT MON JUN 11 2012 VALID 131200Z - 141200Z ...SYNOPSIS... A WEAK MID-LEVEL IMPULSE OVER THE DAKOTAS EARLY WED SHOULD DAMPEN AS IT TRACKS ACROSS THE UPPER MS VALLEY...WHILE AN UPSTREAM SHORT WAVE TROUGH DEVELOPS ACROSS SWRN CANADA/FAR NWRN CONUS. GUIDANCE DIFFERS SUBSTANTIALLY WITH THE AMPLITUDE/LOCATION OF THE LEAD IMPULSE ASSOCIATED WITH THIS UPSTREAM TROUGH. THE ECMWF/CMC ARE MORE AMPLIFIED/FASTER COMPARED TO NCEP GUIDANCE. THIS RESULTS IN A MORE PROMINENT SURFACE COLD FRONT EJECTING EWD ACROSS THE NRN PLAINS BY EARLY THU. WITH A SURFACE ANTICYCLONE CENTERED OVER THE GREAT LAKES...SLY FLOW WILL RESULT IN THE POLEWARD ADVECTION OF RICHER MOISTURE IN THE PLAINS AHEAD OF A DRYLINE THAT SHOULD EXTEND FROM THE WRN DAKOTAS TO THE SRN HIGH PLAINS ON WED AFTERNOON. ...PLAINS... A BROAD SWATH OF LOW-END SEVERE POTENTIAL IS APPARENT DURING THE PERIOD...BUT LOWER-THAN-AVERAGE CONFIDENCE IN MODEL GUIDANCE ALONG WITH UNCERTAINTIES OVER THE EFFECTS OF CONVECTION FROM D2 MAKE IDENTIFYING CORRIDORS OF SLIGHT RISK NEBULOUS ATTM. MCS CLUSTERS MAY BE ONGOING AT 12Z/WED...MOST PROBABLE INVOF RED RIVER OF THE SOUTH ALONG REMNANT CONVECTIVE OUTFLOW/FRONTAL BOUNDARY AND IN PARTS OF THE MID-MO VALLEY IN ASSOCIATION WITH A WEAK MID-LEVEL IMPULSE. HOW THIS ACTIVITY /ESPECIALLY SOUTH/ AFFECTS THE DEGREE OF NWD MOISTURE TRANSPORT IS UNCLEAR. ALTHOUGH A BELT OF MODERATELY STRONG MID-LEVEL WLYS SHOULD PERSIST FROM THE NEB/KS BORDER AREA NWD...POTENTIAL FOR WEAK SHORT WAVE RIDGING ALONG WITH THE AFOREMENTIONED MOISTURE CONCERN...RENDER UNCERTAINTY OVER DIURNAL COVERAGE OF TSTMS ALONG THE NRN EXTENT OF THE DRYLINE. FARTHER S...GUIDANCE IS FAIRLY CONSISTENT IN MODERATING MID-LEVEL WLYS IN THE SRN PLAINS RELATIVE TO PRIOR DAYS...WHICH SHOULD YIELD RELATIVELY MARGINAL SEVERE POTENTIAL COMPARED TO D1-2. ..GRAMS.. 06/11/2012
via SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day3otlk_0730.html
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