Damaging Wind in North Dakota, July 17, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
240 AM CDT WED JUL 17 2002

CONCERNS WITH FORECAST THIS MORNING STEM FROM MESOSCALE CONVECTIVE
SYSTEM MOVING INTO WESTERN NORTH DAKOTA NOW. RAIN/THUNDERSTORM
ELEMENTS IN IT WERE MOVING NORTHEAST WITH DEVELOPMENT ON THE
SOUTHERN END. QUESTION HERE IS WHO HAS HIGHEST RAIN CHANCES. THAT
LOOKS LIKE THE NORTH AND WILL GO CATEGORICAL WITH STORMS THERE THIS
MORNING...POPS SOUTH...AND NO RAIN AT ALL IS EXPECTED ON THE SOUTH
DAKOTA BORDER. OTHER PROBLEM WITH SYSTEM IS ITS EFFECT ON HIGH
TEMPERATURES TODAY. EXPANSIVE CLOUD SHIELD WILL RETARD MORNING
HEATING. AS SYSTEM WEAKENS AND PUSHES EAST QUESTION BECOMES WHETHER
OR NOT THE WEST BREAKS OUT INTO SUNSHINE. MY FEELING IS THAT
SUNSHINE WILL BREAK OUT OVER THE WEST THIS AFTERNOON AND INDUCE MORE
STORM DEVELOPMENT BY LATER IN THE DAY. ANOTHER MCS IS EXPECTED TO
FORM TONIGHT AND MOVE THROUGH THE STATE. WILL LOWER HIGHS TODAY
BASED ON ABOVE REASONING...BUT ONLY ONE CATEGORY AS ANY SUNSHINE
THAT DOES BREAK OUT COULD RESULT IN RAPID TEMPERATURE RISES LATER.

AS FAR AS MODELS GO...STUCK WITH ETA. ALL MODELS HAD FORECAST THE
SOUTH DAKOTA SURFACE LOW...AND ASSOCIATED WARM FRONT...TOO FAR
NORTH. WITH SYSTEM FARTHER SOUTH THAT HAS ALLOWED RAIN AREA TO SHIFT
SOUTH AS WELL. THERE IS NOW A BETTER CHANCE FOR THE EXTREMELY DRY
AREAS GETTING SOME RAIN. STILL THE HIGHEST CHANCES AND HIGHEST
AMOUNTS ARE EXPECTED OVER THE NORTHERN AND CENTRAL PARTS OF THE
STATE...ALONG/NORTH OF HIGHWAY 200. WITH WEAKENING H5 RIDGE
TONIGHT...AND THE WEAKENING THERMAL RIDGE...AT LEAST SOME RAIN
SHOULD FALL TONIGHT EVEN AS FAR SOUTH AS THE SOUTHERN BORDER
COUNTIES.

SEVERE WEATHER WILL BE POSSIBLE THIS EVENING BEFORE STORMS FORM INTO
A SYSTEM. WITH LARGE AREA OF RAIN/STORMS SEVERE THREAT WILL DECREASE
TO ISOLATED AT WORST.

NO CHANGES TO LONGER TERM FORECAST.

.BIS...NONE.

JP MARTIN

NDZ001-009-017-170800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WILLISTON ND
1259 AM CDT WED JUL 17 2002

AT 1245 AM CDT LOCAL RADAR INDICATED A LINE OF THUNDERSTORMS WEST OF
WILLISTON MOVING NORTHEASTEAST AT 40 MPH. THE STORMS ARE EXPECTED TO
ENTER WESTERN DIVIDE...WILLIAMS AND MCKENZIE COUNTIES AND CONTINUE
THROUGH THE COUNTIES DURING THE LATE NIGHT AND EARLY MORNING HOURS.
THESE STORMS MAY PRODUCE PERIODS OF MODERATE TO HEAVY RAIN...BRIEF
GUSTY WINDS AND DANGEROUS LIGHTNING. ALTHOUGH THE STORMS DO NOT
CURRENTLY MEET SEVERE CRITERIA...THE POSSIBLITY OF DEVELOPMENT
REMAINS. USE CAUTION TO ASSURE SAFETY DURING OUTDOOR ACTIVITY.

KROLAK