Severe Thunderstorm Warning 266, NWS Bismarck, ND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
245 AM CDT WED AUG 8 2007

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT...
LATEST SATELLITE IMAGERY SHOWS EJECTING SHORTWAVE OVER SOUTHERN
MONTANA...JUST NORTH OF THE IDAHO/MONTANA BORDER MOVING EAST.
THIS WAVE WILL REACH BILLINGS BY 12Z...THEN TO DICKINSON BY
18Z...AND JUST EAST OF BISMARCK BY 00Z. SCATTERED SHOWERS AND
THUNDERSTORMS AHEAD OF THIS WAVE WILL CONTINUE THIS MORNING. LATEST
MSAS ANALYSIS SHOWS A VERY WEAK SURFACE COLD FRONT OVER EASTERN
MONTANA THIS MORNING. THIS FRONT WILL SLUGGISHLY MOVE EAST AND
BECOME LOOSELY DEFINED BY THIS AFTERNOON...LENDING ITSELF TO JUST
WHAT LOOKS LIKE A BAGGY SFC TROUGH BY THE TIME IT REACHES
BISMARCK. SURFACE CONVERGENCE WILL BE WEAK...BUT WILL LIKELY BE
ENOUGH TO HELP INITIATE ADDITIONAL TSTMS AS AFOREMENTIONED
SHORTWAVE GETS CLOSER THIS AFTERNOON AND EVENING. SPC HAS EASTERN
CENTRAL...AND EASTERN NORTH DAKOTA IN A SLIGHT RISK SCENARIO FOR
THIS AFTERNOON AND EVENING WITH STRONG TO SEVERE THUNDERSTORMS
DEVELOPING. LATEST 4KM WRF SIMULATED COMPOSITE RADAR REFLECTIVITY
LOOP SHOWS PRECIP MAINLY CONFINED TO EAST CENTRAL AND EASTERN
NORTH DAKOTA THIS AFTERNOON/EVENING...IN LINE WITH SPC SLIGHT
RISK AREA. AFTER COLLABORATING WITH GRAND FORKS AND ABERDEEN...WILL
MENTION SEVERE WORDING IN THE ZFP VIA GRIDS. WILL DIMINISH PRECIP
EARLY THIS AFTERNOON IN THE WESTERN ZONES AND GRADUALLY END IT IN
THE CENTRAL AND EASTERN CWA BY AROUND 06Z. MODELS HAVE THE BAGGY
TROUGH LOOMING OVER THE AREA WITH ADDITIONAL SHORTWAVES AND WEAK
SURFACE FEATURES MOVING THROUGH THURSDAY INTO FRIDAY NIGHT. AT
THIS TIME ITS HARD TO PINPOINT WHERE THE POPS WOULD MAX OUT...THUS
WILL BLANKET MOST OF THE CWA WITH ISOLATED UNTIL SOMETHING BECOMES
MORE DEFINITIVE.

.LONG TERM...SATURDAY THROUGH TUESDAY...
00Z GFS SIMILAR TO YESTERDAYS RUN AND QUITE SIMILAR TO THE ECMWF.
UPPER TROUGH AND SURFACE FRONT MOVE THROUGH THE FORECAST AREA ON
SATURDAY SO LEFT SOME LOW POPS. THEN...A COOLER AND DRIER AIRMASS
MOVES INTO WESTERN AND CENTRAL NORTH DAKOTA BEHIND THIS UPPER
TROUGH. MAIN CHANGES WERE TO COOL DOWN THE MAX TEMPS A BIT FOR
SUNDAY AND TO REMOVE THE LOW POPS FOR SATURDAY NIGHT AND SUNDAY.
LEFT IN SOME LOW POPS FOR SUNDAY NIGHT.

RIDGE REBUILDS OVER THE NORTHERN PLAINS FOR MONDAY AND TUESDAY. SO
EXPECT TEMPERATURES TO REBOUND BACK INTO THE 80S AND 90S WITH
GENERALLY DRY CONDITIONS. THIS COVERED WELL IN CURRENT FORECAST SO
NO CHANGES MADE FOR MONDAY AND TUESDAY.

&&

.AVIATION...
SURFACE TROUGH WILL REMAIN ACROSS WESTERN NORTH DAKOTA TODAY AS AN
UPPER LEVEL TROUGH MOVES ACROSS THE AREA. THIS WILL BRING SCATTERED
SHOWERS AND THUNDERSTORMS OVER THE AREA TODAY. SOME OF THESE STORMS
COULD BE QUITE STRONG WITH GUSTY WINDS AND HAIL. OUTSIDE OF THE
THUNDERSTORMS...VFR CONDITIONS EXPECTED. THUNDERSTORM THREAT SHOULD
BE EAST OF THE AREA BY THIS EVENING.

&&

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

KS/JF

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BISMARCK ND
430 AM CDT WED AUG 8 2007

NDZ001>005-009>013-017>023-025-031>037-040>048-050-051-090930-
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-
430 AM CDT WED AUG 8 2007 /330 AM MDT WED AUG 8 2007/

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

SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE
MORNING THEN BECOME ISOLATED THIS AFTERNOON IN CENTRAL AND WESTERN
NORTH DAKOTA. A WEAKENING COLD FRONT OVER EASTERN MONTANA WILL
FALL APART AS IT MOVES TOWARD BISMARCK EARLY THIS AFTERNOON...
FOLLOWED BY AN UPPER LEVEL DISTURBANCE TRAVERSING ACROSS THE STATE
LATER TODAY. THIS WILL HELP INITIATE ADDITIONAL SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING MAINLY OVER OUR EASTERN
ZONES. SOME OF THESE THUNDERSTORMS MAY BECOME SEVERE.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A WEAK TROUGH WILL REMAIN AT THE SURFACE ACROSS NORTH DAKOTA WITH
A SERIES OF UPPER DISTURBANCES MOVING ACROSS THE STATE. ANY ONE OF
THESE COULD TRIGGER ISOLATED SHOWERS AND THUNDERSTORMS THURSDAY
INTO SATURDAY. APPEARS SUNDAY THROUGH TUESDAY WILL BE OUR DRIEST
DAYS WITH LITTLE OR NO THREAT FOR ANY PRECIPITATION.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TODAY INTO EARLY THIS EVENING.

KS