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
No Risk Areas Forecast
Probabilistic Damaging Wind 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 %
54,508
578,213
Missoula, MT...Great Falls, MT...Butte, MT...Helena, MT...Kalispell, MT...
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
5 %
98,606
5,111,021
Milwaukee, WI...Grand Rapids, MI...Green Bay, WI...Wyoming, MI...Appleton, WI...
SPC AC 141626
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1126 AM CDT FRI AUG 14 2015
VALID 141630Z - 151200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER THE WRN MT AREA...
...THERE IS A MRGL RISK OF SVR TSTMS OVER THE NRN INTERMOUNTAIN
REGION AND NRN ROCKIES...
...THERE IS A MRGL RISK OF SVR TSTMS OVER PARTS OF WI AND LOWER
MI...
...SUMMARY...
SEVERAL STRONG TO SEVERE STORMS ARE EXPECTED ACROSS THE NORTHERN
ROCKIES AND PORTIONS OF THE INTERMOUNTAIN WEST DURING THE AFTERNOON
AND EVENING...WITH THE PRIMARY THREAT BEING SEVERE WIND GUSTS.
OTHER STRONG AND ISOLATED SEVERE STORMS MAY DEVELOP OVER PARTS OF
WISCONSIN AND LOWER MICHIGAN.
...NRN ROCKIES AND INTERMOUNTAIN REGION...
WATER VAPOR IMAGERY INDICATES THE UPPER LOW ALONG THE PACIFIC NW
COAST IS BEGINNING TO OPEN INTO A SHORT WAVE TROUGH AND MOVE NEWD AS
THE STRONGEST MID-UPPER LEVEL WINDS ROTATE INTO THE ERN PORTION OF
THE CIRCULATION. THIS SYSTEM IS FORECAST TO CONTINUE INLAND ACROSS
WA AND OREGON THIS AFTERNOON BEFORE REACHING NWRN MT BY THE END OF
THE PERIOD. DCVA IN ADVANCE OF THE TROUGH COUPLED WITH LOW-LEVEL
CONVERGENCE ALONG A STRONG COLD FRONT MOVING ACROSS THE REGION AND
TERRAIN-INDUCED OROGRAPHIC CIRCULATIONS WILL PROVIDE STRONG ASCENT
FOR ADDITIONAL CONVECTIVE DEVELOPMENT...ESPECIALLY THIS AFTERNOON
AND EVENING.
WIDELY SCATTERED CONVECTION THIS MORNING IS EVIDENT FROM ERN PARTS
OF WA/OREGON INTO NRN ID AND SWRN MT...WITH VISIBLE IMAGERY SHOWING
CONSIDERABLE CLOUD-FREE REGIONS OVER SRN/CENTRAL ID AND WRN MT.
STRONG LOW-LEVEL DIABATIC HEATING IS LIKELY TO OCCUR IN THESE
AREAS...WHICH WILL ENHANCE THE PRE-EXISTING STEEP LAPSE RATE
ENVIRONMENT WHERE A DEEPENING WELL-MIXED PBL IS EXPECTED IN ADVANCE
OF THE ADVANCING COLD FRONT. DESPITE MODEST MOISTURE WITH PW VALUES
GENERALLY LESS THAN 1 INCH...IT WILL BE SUFFICIENT FOR SCATTERED
HIGH-BASED STORMS TO INCREASE THIS AFTERNOON FROM CENTRAL ID INTO
WRN MT. STRONG VERTICAL SHEAR WITHIN THE CONVECTIVE CLOUD LAYER IS
LIKELY TO ENHANCE STORM ORGANIZATION...AND RAPID CELL MOVEMENT
WITHIN A DEEPLY MIXED PBL SHOULD ENHANCE DOWNWARD TRANSFER OF STRONG
HORIZONTAL MOMENTUM TO THE SURFACE WITH PRIMARY POTENTIAL BEING
DAMAGING WIND GUSTS. THE ACTIVITY IS EXPECTED TO SPREAD NEWD TOWARD
CENTRAL MT THIS EVENING WITH STORMS WEAKENING AFTER SUNSET.
...PARTS OF WI AND LOWER MI...
IN THE WAKE OF A SWD MOVING CLOUD BAND OVER SRN PARTS OF WI AND
LOWER MI /ASSOCIATED WITH A WEAK SHORT WAVE TROUGH/...THE AIR MASS
REMAINS MOIST AND UNSTABLE OVER WI AND LOWER MI WITH SURFACE DEW
POINTS IN THE UPPER 60S AND LOWER 70S. 12Z RAOBS AT GRB...APX AND
DTX EXHIBITED MODERATELY STEEP RESIDUAL LAPSE RATES...AND WITH
STRONG DIABATIC HEATING EXPECTED INTO THE AFTERNOON...THE AIR MASS
WILL BECOME INCREASINGLY UNSTABLE WITH MLCAPE OF 2000-3000 J/KG.
DESPITE LIMITED FORCING FOR LARGE-SCALE ASCENT AND A GENERAL LACK OF
LOW-LEVEL BOUNDARIES TO FOCUS STORM DEVELOPMENT...THE FAVORABLE
THERMODYNAMIC ENVIRONMENT AND WEAKENING CAP SUGGEST POTENTIAL FOR A
FEW STRONG/SEVERE MULTI-CELL STORMS TO DEVELOP THIS AFTERNOON. THE
ACTIVITY WILL MOVE SWD THROUGH THE EVENING BUT WEAK VERTICAL SHEAR
SHOULD LIMIT THE OVERALL SEVERE THREAT.
..WEISS/COHEN.. 08/14/2015
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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