Jul 21, 2014 1300 UTC Day 1 Convective Outlook

DAY 1 CONVECTIVE OUTLOOK  

   NWS STORM PREDICTION CENTER NORMAN OK
   0756 AM CDT MON JUL 21 2014

   VALID 211300Z - 221200Z

   ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF ND...SD...AND
   MN...

   ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK
   AREA...FROM WRN ND ESEWD INTO WRN UPR MI AND CNTRL WI...

   ...SUMMARY...
   DAMAGING WINDS AND LARGE HAIL ARE LIKELY FROM NORTH DAKOTA INTO
   WESTERN AND NORTHERN MINNESOTA AND NORTHERN SOUTH DAKOTA THIS 
   AFTERNOON INTO TONIGHT. SOME WIND GUSTS COULD BE PARTICULARLY
   DAMAGING. OTHER STORMS WITH SEVERE WIND AND HAIL MAY OCCUR OVER
   REMAINDER OF MINNESOTA AND OVER PARTS OF WISCONSIN AND UPPER
   MICHIGAN. ISOLATED STORMS WITH STRONG WINDS WILL BE POSSIBLE ACROSS
   THE CENTRAL AND SOUTHERN HIGH PLAINS...AND OVER THE GREAT BASIN.

   ...SYNOPTIC SETUP...
   MODERATE WSW FLOW WILL PREVAIL ACROSS THE NRN RCKYS...THE NRN PLNS
   AND UPR MS VLY THIS PERIOD...ON NRN FLANK OF UPR RIDGE BUILDING NEWD
   FROM THE SRN RCKYS. WITHIN THIS FLOW...SATELLITE AND VWP DATA
   SUGGEST PRESENCE OF SEVERAL LOW-AMPLITUDE DISTURBANCES THAT WILL
   TRACK ACROSS THE REGION. ONE OF THESE...NOW OVER ERN WY...SHOULD
   CONTINUE ENE INTO THE ERN DAKOTAS BY EVE AND TO LK SUPERIOR BY 12Z
   TUE AS ANOTHER...STRONGER IMPULSE MOVES FROM SE BC TO SRN MB.

   AT THE SFC...WEAK FRONTAL SURGES INTO THE NRN PLNS IN RECENT DAYS
   HAVE BECOME NEARLY STNRY THIS MORNING OVER THE DAKOTAS/MN. THE
   WSW-ENE ORIENTED BOUNDARIES SHOULD REMAIN MORE OR LESS STNRY THROUGH
   THE DAY AS WEAK CYCLOGENESIS OCCURS IN NRN SD...LARGELY IN RESPONSE
   TO PASSING UPR IMPULSE. THIS WAVE SHOULD TRACK NE TO NEAR DULUTH BY
   12Z TUE...POSSIBLY AUGMENTED BY AN MCS-RELATED CIRCULATION OR MCV.

   ...NRN PLNS/UPR MS VLY TODAY/TNGT...
   A POOL OF VERY UNSTABLE AIR /MLCAPE AOA 5000 J PER KG/ WILL EMERGE
   WITH STRONG SFC HEATING AND CONTINUED EVAPOTRANSPIRATION EXPECTED
   TODAY INVOF WEAK FRONTS STALLED WSW-ENE OVER ND AND CNTRL/NRN MN.
   CURRENT SFC AND SATELLITE DATA SUGGEST THAT COMBINATION OF HEATING
   AND ASCENT WITH WY IMPULSE COULD INITIATE STORMS BY MID TO LATE AFTN
   IN PARTS OF WRN AND CNTRL ND...WHERE LOW-LVL CONVERGENCE SHOULD BE
   MAXIMIZED ALONG AND N OF THE BOUNDARIES.

   GIVEN DEGREE OF BUOYANCY...THE STORMS LIKELY WILL QUICKLY BECOME SVR
   AS STORM OUTFLOW PREFERENTIALLY SPREADS E OR ENEWD. VERY LARGE
   HAIL...LOCALLY DMGG WIND...AND A COUPLE TORNADOES MAY OCCUR AS
   SUSTAINED STORMS...INCLUDING INTENSE MULTICELLS AND A FEW
   SUPERCELLS...ORGANIZE INTO CLUSTERS. A MORE ORGANIZED DAMAGING
   WIND/POTENTIAL DERECHO THREAT MAY DEVELOP BY EVE AS STORMS CONTINUE
   TO MERGE/DEVELOP EWD INTO ERN ND AND NRN/WRN MN. VERY STEEP MID-LVL
   LAPSE RATES ASSOCIATED WITH STOUT EML INITIALLY MAY LIMIT ANY SEWD
   PROPAGATIONAL COMPONENT TO THE CONVECTIVE SYSTEM...ALTHOUGH WITH
   TIME AND EWD EXTENT...THE MCS AND ITS ASSOCIATED WIND THREAT
   ULTIMATELY COULD EXPAND A BIT SEWD...PERHAPS AS FAR AS NRN/WRN WI
   EARLY TUE.

   FARTHER S...A MORE CONDITIONAL/SPORADIC SVR THREAT MAY DEVELOP FOR
   ISOLD SVR STORMS ALONG MIDDLE AND ERN PORTIONS OF THE LOW-LVL
   MOISTURE AXIS FROM NE SD SEWD INTO S CNTRL MN/NE IA LATER TODAY INTO
   TNGT. STRONG EML CAP SHOULD LIMIT COVERAGE. BUT GIVEN VERY  STRONG
   INSTABILITY...A CONDITIONAL RISK FOR SVR HAIL...WIND...AND PERHAPS A
   TORNADO WILL EXIST.

   ...CNTRL/SRN HIGH PLNS THIS AFTN/EVE...
   VERY STRONG HEATING ALONG LEE TROUGH/DRY LINES SEGMENTS BENEATH THE
   UPR RIDGE WILL YIELD INVERTED-V SOUNDINGS WITH 500-1000 J/KG MUCAPE
   FROM WRN NEB SSW INTO ERN NM/W TX. SHEAR WILL BE WEAK.  BUT ISOLD TO
   PERHAPS WDLY SCTD STORMS APPEAR LIKELY LATE THIS AFTN/EVE...AND
   THOSE THAT DO FORM WILL BE CAPABLE OF LOCALLY STRONG TO SVR WIND
   GUSTS.