Aug 1, 2015 2000 UTC Day 1 Convective Outlook
Updated: Sat Aug 1 19:42:01 UTC 2015 (20150801 2000Z Day 1 shapefile | 20150801 2000Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20150801 2000 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 47,930 4,906,651 Minneapolis, MN...St. Paul, MN...Sioux Falls, SD...Rochester, MN...Bloomington, MN...
MARGINAL 181,432 11,851,626 Omaha, NE...Lincoln, NE...Madison, WI...Aurora, IL...Rockford, IL...
Probabilistic Tornado Graphic
20150801 2000 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
2 % 79,165 5,776,054 Minneapolis, MN...St. Paul, MN...Sioux Falls, SD...Rochester, MN...Bloomington, MN...
Probabilistic Damaging Wind Graphic
20150801 2000 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 48,417 4,930,555 Minneapolis, MN...St. Paul, MN...Sioux Falls, SD...Rochester, MN...Bloomington, MN...
5 % 180,426 11,934,186 Omaha, NE...Lincoln, NE...Madison, WI...Aurora, IL...Rockford, IL...
Probabilistic Large Hail Graphic
20150801 2000 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 48,841 5,028,513 Minneapolis, MN...St. Paul, MN...Sioux Falls, SD...Rochester, MN...Bloomington, MN...
5 % 174,703 6,869,724 Omaha, NE...Lincoln, NE...Madison, WI...Rockford, IL...Sioux City, IA...
   SPC AC 011942

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0242 PM CDT SAT AUG 01 2015

   VALID 012000Z - 021200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN SD INTO SRN MN...

   ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS THE NRN PLAINS AND UPPER
   MS VALLEY...

   ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS ERN MAINE...

   ...SUMMARY...
   SEVERE THUNDERSTORMS MAY DEVELOP THIS AFTERNOON AND MOVE
   SOUTHEASTWARD THIS EVENING ACROSS PARTS OF THE NORTH-CENTRAL PLAINS
   AND UPPER MIDWEST...OFFERING DAMAGING WIND AND SEVERE HAIL
   POTENTIAL. A FEW THUNDERSTORMS MAY PRODUCE HAIL AND DAMAGING GUSTS
   NEAR SEVERE LEVELS IN NEW ENGLAND.

   ...NRN PLAINS...
   GIVEN SATELLITE AND SURFACE OBSERVATIONS AS WELL AS RECENT MODEL
   OUTPUT...HAVE EXPANDED THE SLIGHT RISK A BIT NWWD ACROSS NERN SD/WRN
   MN WHERE STORMS ARE EXPECTED TO INITIATE LATER THIS AFTERNOON.
   CONVERGENCE IS CURRENTLY MAXIMIZED ACROSS SERN ND/NERN SD...WITH
   INSTABILITY LEVELS RAPIDLY INCREASING VIA HEATING. DAMAGING WINDS
   AND HAIL ARE LIKELY IN THE SLIGHT RISK CORRIDOR AS STORMS TRAVEL
   SEWD LATER TODAY. THE GREATEST RISK WILL BE ACROSS WRN PORTIONS OF
   THE SLIGHT RISK AREA WITH MORE OF A CONDITIONAL THREAT OVER SERN
   MN/WI AS CIN INCREASES AHEAD OF THE DEVELOPING STORMS.

   ..JEWELL.. 08/01/2015

   .PREV DISCUSSION... /ISSUED 1117 AM CDT SAT AUG 01 2015/

   ...MIDWEST STATES...
   A BROAD UPPER RIDGE IS PRESENT TODAY OVER THE WESTERN STATES...WITH
   CYCLONIC FLOW ALOFT FROM THE NORTHERN PLAINS ACROSS THE NORTHEAST
   STATES.  WATER VAPOR LOOP SHOWS A SUBTLE SHORTWAVE TROUGH MOVING
   ACROSS EASTERN MT/WESTERN ND.  THIS FEATURE WILL HELP TO INITIATE
   ISOLATED AFTERNOON THUNDERSTORMS OVER PARTS OF EASTERN ND/SD AND
   CENTRAL/SOUTHERN MN.  THOSE STORMS THAT FORM WILL TRACK
   EAST-SOUTHEASTWARD THROUGH THE EVENING...WHERE MODERATE CAPE VALUES
   AND FAVORABLE VERTICAL SHEAR WILL SUPPORT SUPERCELL/BOWING STORM
   STRUCTURES.  HAIL AND DAMAGING WINDS WILL BE POSSIBLE IN THE
   STRONGER CORES.  

   FARTHER SOUTH...CONSIDERABLE UNCERTAINTY EXISTS REGARDING THE
   COVERAGE AND LOCATION OF STRONG CONVECTION.  OVERNIGHT CONVECTION
   OVER EASTERN NEB HAS CREATED WIDESPREAD CLOUDS THAT WILL REDUCE
   HEATING/DESTABILIZATION AND LESSEN THE PROBABILITY OF CONVECTIVE
   INITIATION.  12Z MODEL SOLUTIONS SHOW LITTLE CONSISTENCY ACROSS MUCH
   OF NEB/IA AND NORTHERN IL.  THEREFORE...HAVE BACKED OFF TO MRGL
   CATEGORY FOR THIS REGION AND WILL RE-EVALUATE IN LATER UPDATES.

   ...NEW ENGLAND...
   SATELLITE/RADAR DATA SHOW SCATTERED THUNDERSTORMS DEVELOPING OVER
   PARTS OF EASTERN QUEBEC AND NORTHERN NEW ENGLAND.  THIS ACTIVITY
   WILL AFFECT PARTS OF VT/NH/ME THROUGH THE MID AFTERNOON BEFORE
   MOVING EASTWARD AND AWAY FROM THE US.  FORECAST SOUNDINGS SHOW
   CONSIDERABLE EFFECTIVE SHEAR FOR FAST-MOVING STORMS CAPABLE OF GUSTY
   WINDS.  HOWEVER...THERMODYNAMIC PROFILES ARE RATHER BENIGN WITH MID
   LEVEL LAPSE RATES ONLY AROUND 6 C/KM AND MLCAPE VALUES OF 500-800
   J/KG.  ISOLATED SEVERE STORMS ARE POSSIBLE WITH GUSTY WINDS AND
   HAIL...BUT OVERALL THREAT APPEARS MARGINAL.

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z