Had some weather move through last night

and during it I saw this come out. I think there's a slight problem in definition here:

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TONIGHT OVER PORTIONS
OF CENTRAL OKLAHOMA.

LOCATION...
THE SLIGHT RISK IS LOCATED EAST OF A LINE FROM STILLWATER...TO
MUSTANG...TO WAURIKA OKLAHOMA.

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS WILL BE FROM 9 PM
THROUGH 2 AM.

IMPACTS...
LARGE HAIL UP TO ONE AND ONE HALF INCHES IN DIAMETER...CAPABLE OF
DAMAGING AUTOMOBILES...VEGETATION...AND THE ROOFTOPS AND WINDOWS OF
STRUCTURES.

DAMAGING WIND GUSTS OF 65 TO 70 MPH.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL SHOULD PLAN
FOR SEVERE WEATHER OPERATIONS TONIGHT...LASTING UNTIL EARLY
THURSDAY MORNING IN SOME EASTERN LOCATIONS.

DISCUSSION...
A STRONG UPPER LEVEL TROUGH WILL CONTINUE TO IMPACT THE SOUTHERN
PLAINS TONIGHT. THUNDERSTORMS WILL CONTINUE TO FORM NEAR AND TO THE
SOUTHEAST OF A COLD FRONT. STRONG DEEP LAYER WIND SHEAR...INCLUDING
THE PRESENCE OF A SOUTHWESTERLY LOW LEVEL JET OVER THE SLIGHT RISK
AREA...WILL RESULT IN SOME STORMS BECOMING STRONG TO SEVERE. STRONG
WINDS THROUGHOUT THE DEPTH OF THE ATMOSPHERE WILL YIELD FAST MOVING
STORMS...SOME GREATER THAN 45 MPH...AND THIS WILL ENHANCE THE
POTENTIAL FOR DAMAGING STRAIGHT LINE WINDS.

THE SEVERE WEATHER THREAT WILL DIMINISH OVERNIGHT AS THE FRONT
BRINGS COOLER...STABLE AIR INTO THE REGION.

PROBABILITY TABLE...
VALID THROUGH 700 AM CST THURSDAY NOV 6.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
NWS NORMAN COUNTY WARNING AREA...100 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...90 PERCENT.

OTHER HAZARDOUS WEATHER...
AN URBAN AND SMALL STREAM FLOOD ADVISORY IS IN EFFECT UNTIL 1045 PM
ACROSS PORTIONS OF LOGAN AND PAYNE COUNTIES RECEIVING BETWEEN ONE
AND THREE INCHES OF RAIN THIS AFTERNOON. SEE THE ADVISORY FOR
DETAILS.

I'd like to know what they define as a 'high' risk.