Severe Thunderstorm Warning 287, NWS Bismarck, ND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
300 PM CDT WED AUG 23 2006

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT...
PROBLEMS TODAYS PACKAGE ARE CHANCES AND TIMING OF CONVECTION TONIGHT
AND THURSDAY. GFS PREFERRED MODEL TODAY AND  USED TO TIME SYSTEMS
AND WINDS THROUGH THE CWA.

VERY STEEP LAPSE RATES EVIDENT ON 14Z AND 17Z BISMARCK SOUNDINGS
WITH CAPE VALUES DECREASING FROM 5300 JOULES AT 12Z TO A MORE
MODERATE 4200 AT 17Z. HOWEVER NO MECHANISM PRESENT AT THIS TIME TO
INITIATE CONVECTION. HOWEVER WITH WEAK SHORT WAVE ON WATER VAPOR
LOOP PUSHING INTO WESTERN PORTIONS OF CWA AND VERY UNSTABLE ELEVATED
WILL CONTINUE SLIGHT CHANCE POPS OVER CWA. BETTER CHANCES OF
CONVECTION BEGINNING EARLY TOMORROW AND CONTINUING THROUGH FRIDAY AS
SURFACE LOW MOVES SLOWLY ACROSS THE NORTHERN PLAINS DRIVEN BY MID
LEVEL SHORTWAVES IN FAIRLY STRONG FLOW ROTATING AROUND LOW DROPPING
SOUTH INTO PRAIRIE PROVINCES OF SOUTH CENTRAL CANADA.

SOUTHWEST FLOW ALOFT AGAIN DEVELOPS FRIDAY AS OCCLUDED SURFACE
SYSTEM EXITS PLAINS INTO NORTHERN MINNESOTA. GFS PAINTS SOME QPF
OVER SOUTHERN PORTIONS OF STATE OF SATURDAY BUT WILL LEAVE IT DRY
FOR NOW AS THE NAM IS DRY AND THE MODELS(ESPECIALLY THE NAM) HAVE
BEEN FLOPPING BACK AND FORTH SOME THE PAST SEVERAL DAYS.

NORTHWEST FLOW OVER NORTHERN PLAINS SATURDAY NIGHT AND SUNDAY AS
RIDGE AGAIN BUILDS OVER THE NORTHERN ROCKIES. TEMPERATURES ON SLOW
DOWNWARD TREND WITH HIGHS DROPPING FROM THE 90S TODAY INTO THE 70S
ON SATURDAY.

.LONG TERM...SUNDAY THROUGH WEDNESDAY...
THE LONG TERM PERIOD IS CHARACTERIZED BY THE UPPER LEVEL WESTERN US
RIDGE IN PLACE OVER THE ROCKIES BRINGING DRY NORTHWEST FLOW ACROSS
NORTH DAKOTA SUNDAY THROUGH TUESDAY. ON WEDNESDAY THE UPPER LEVEL
RIDGE AXIS HAS MOVED EAST INTO THE WESTERN PLAINS AND ALLOWING
SURFACE LOW PRESSURE TO DEVELOP IN THE LEE OF THE ROCKIES WITH GOOD
SOUTHEAST SURFACE FLOW AND INCREASING DEWPOINTS. WILL NOT INTRODUCE
PRECIPITATION FOR WEDNESDAY AT THIS TIME AS IS THE LAST DAY IN THE
EXTENDED PERIOD...AND WILL WAIT FOR LATER FORECASTS FOR DAY-TO-DAY
CONSISTENCY IN THE GFS MODEL FOR THIS EASTWARD MOVEMENT OF THE
LONGWAVE RIDGE AXIS. OTHERWISE SEASONABLE TEMPERATURES WITH HIGHS
FROM THE UPPER 70S TO LOWER 90S AND LOWS MAINLY IN THE 50S.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

HW/JV

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BISMARCK ND
458 AM CDT WED AUG 23 2006

NDZ001>005-009>013-017>023-025-031>037-040>048-050-051-241000-
DIVIDE-BURKE-RENVILLE-BOTTINEAU-ROLETTE-WILLIAMS-MOUNTRAIL-WARD-
MCHENRY-PIERCE-MCKENZIE-DUNN-MERCER-OLIVER-MCLEAN-SHERIDAN-WELLS-
FOSTER-GOLDEN VALLEY-BILLINGS-STARK-MORTON-BURLEIGH-KIDDER-
STUTSMAN-SLOPE-HETTINGER-GRANT-BOWMAN-ADAMS-SIOUX-EMMONS-LOGAN-
LA MOURE-MCINTOSH-DICKEY-
458 AM CDT WED AUG 23 2006 /358 AM MDT WED AUG 23 2006/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
NORTH DAKOTA...NORTHWEST NORTH DAKOTA...SOUTH CENTRAL NORTH
DAKOTA...SOUTHEAST NORTH DAKOTA AND SOUTHWEST NORTH DAKOTA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS ARE FORECAST TO BREAK OUT OVER WESTERN AND NORTHERN
NORTH DAKOTA LATE TODAY INTO TONIGHT. ISOLATED SEVERE STORMS ARE
POSSIBLE WITH HIGH WIND THE MAIN THREAT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

SEVERE THUNDERSTORMS ARE FORECAST TO DEVELOP OVER CENTRAL NORTH
DAKOTA THURSDAY AFTERNOON AND SPREAD EAST. LARGE HAIL WILL BE THE
BIGGEST THREAT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THURSDAY.

JP MARTIN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BISMARCK ND
816 PM CDT WED AUG 23 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0755 PM     HAIL             7 E LEFOR               46.70N 102.40W
08/23/2006  E0.25 INCH       STARK              ND   TRAINED SPOTTER

            PEA SIZE HAIL AND 0.25 INCHES OF RAIN

&&

LLP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BISMARCK ND
855 PM CDT WED AUG 23 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0853 PM     HAIL             9 NNE FAIRFIELD         47.31N 103.13W
08/23/2006  E1.00 INCH       BILLINGS           ND   TRAINED SPOTTER

            HAIL 3/4 TO 1 INCH SIZE

&&

LLP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BISMARCK ND
956 PM CDT WED AUG 23 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0935 PM     HAIL             MANNING                 47.23N 102.77W
08/23/2006  E0.75 INCH       DUNN               ND   CO-OP OBSERVER

            LASTED 10 MINUTES UNTIL 945 PM

&&

VROLLER