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000
FXUS63 KBIS 180256
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
956 PM CDT MON JUN 17 2013

.UPDATE...
ISSUED AT 945 PM CDT MON JUN 17 2013

CONVECTION ACROSS SOUTH CENTRAL NORTH DAKOTA IS FINALLY
DISSIPATING. THE LARGEST HAIL REPORTED WAS NICKEL SIZED IN
NAPOLEON...AND THERE WERE NO REPORTS OF GUSTY WINDS OVER 40 MPH
WITH THE STORMS.

THE MAIN FOCUS WILL TRANSITION TO OUR NEXT CHANCE FOR SEVERE
THUNDERSTORMS MIDWEEK.

UPDATE ISSUED AT 656 PM CDT MON JUN 17 2013

UPDATES WERE FOCUSED ON THE CURRENT AREA OF THUNDERSTORMS
STRETCHING FROM SHERIDAN COUNTY TO GRANT/SIOUX COUNTIES. WHILE
THEY HAVE REMAINED NON-SEVERE THUS FAR...THEY HAVE BEEN CAUSING
VERY HEAVY RAINFALL. AN UNOFFICIAL REPORT OF TO 1.2 INCHES IN 20
MINUTES NEAR VAN HOOK...AND LATER DOUBLING OF SPECIFIC DIFFERENTIAL
PHASE TO OVER 7 DEGREES/KM VIA KBIS RADAR DATA SUPPORTS THE IDEA
THAT RAINFALL RATES MAY HAVE EASILY EXCEEDED 4 INCHES PER HOUR.
THUS FAR...CELLS HAVE BEEN FORWARD PROPAGATING IN AN ENVIRONMENT
OF LIMITED SHEAR. THERE HAS BEEN NO NEED FOR FLOOD
ADVISORIES/WARNINGS...BUT THE SITUATION WILL CONTINUE TO BE
MONITORED CLOSELY.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 327 PM CDT MON JUN 17 2013

REMNANTS OF AN UPPER LOW OVER WESTERN NORTH DAKOTA WILL MOVE EAST
OF THE REGION BY TUESDAY. FOR THE AFTERNOON AND EARLY EVENING
FOCUSED ON THE CLUSTER OF SHOWERS AND SCATTERED THUNDERSTORMS
CURRENTLY OVER THE WEST END OF LAKE SAKAKAWEA. TRACKED THIS TO THE
SOUTH CENTRAL THOUGH EARLY EVENING THEN DIMINISHED POPS BEFORE
SUNSET.

AFTER TONIGHT THE EFFECTS OF THE UPPER LOW WILL DIMINISH OVER THE
REGION AND EXPECT DRY CONDITIONS AFTER MIDNIGHT AND ON TUESDAY.

WARMER TEMPERATURES TUESDAY AS A WEAK UPPER RIDGE MOVES INTO THE
NORTHERN PLAINS. SHOULD SEE HIGHS UPPER 70S TO AROUND 80.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 327 PM CDT MON JUN 17 2013

AN ACTIVE WEATHER PATTERN APPEARS TO BE MORE AND MORE LIKELY FROM
MID WEEK INTO THE UPCOMING WEEKEND AS DETERMINISTIC AND ENSEMBLE
MODELS CONTINUE TO ADVERTISE A RELATIVELY TIGHT ENVELOPE OF
SOLUTIONS WITH THE RIDGE/TROUGH UPPER LEVEL PATTERN THAT TRANSLATES
INTO THE NORTHERN PLAINS. WILL UTILIZE A MODEL BLEND WITH
PERSISTENCE FOR MOST FORECAST ELEMENTS.

TUESDAY EVENING AN UPPER LEVEL RIDGE SHOULD BE SITUATED OVER THE
DAKOTAS...BETWEEN AN UPPER LEVEL LOW/TROUGH OVER HUDSON BAY AND
ANOTHER OVER THE WEST COAST. THE MID-LEVEL CAP IS FORECAST TO BE IN
PLACE OVER THE FRONT RANGE...AND THE MODELS ARE DEPICTING A
SHORTWAVE IMPULSE MOVING NORTHEASTWARD TOWARDS NORTH DAKOTA TUESDAY
NIGHT. KEPT A SLIGHT CHANCE OF THUNDERSTORMS OVER THE SOUTHWEST AND
SOUTH CENTRAL TUESDAY NIGHT...SINCE THE ATMOSPHERE OVER NORTH DAKOTA
SHOULD NOT BE CAPPED.

WEDNESDAY...THE UPPER LEVEL RIDGE BUILDS INTO A SHARP MERIDIONAL
RIDGE AND STRONG WARMING AT MID LEVELS OVER WESTERN NORTH
DAKOTA...WITH STRONG SOUTH WINDS AND A LOW LEVEL JET REACHING INTO
NORTH DAKOTA FROM THE SOUTHERN/CENTRAL PLAINS. MEANWHILE THE LARGE
UPPER LOW/TROUGH MOVES EASTWARD ACROSS THE ROCKIES. STILL KEPT
SLIGHT CHANCE WEST TO 30 PERCENT EAST WITH LINGERING UPPER LEVEL
IMPULSE IN CENTRAL/EASTERN NORTH DAKOTA.

WEDNESDAY NIGHT THROUGH THURSDAY APPEARS TO BE THE BEST CHANCES OF
STRONG TO SEVERE THUNDERSTORMS FOR NORTH DAKOTA...WITH THE STRONG
LOW LEVEL JET IN PLACE...PLENTY OF LOW LEVEL MOISTURE...AND A
SURFACE LOW/TROUGH WITH DRY AIR BEHIND IT TO FOCUS AND MAINTAIN
THUNDERSTORM DEVELOPMENT.

WEDNESDAY NIGHT THROUGH MONDAY THE WESTERN UPPER LEVEL LOW CONTINUES
TO DEVELOP AND MOVE VERY SLOWLY EASTWARD OVER THE ROCKIES...WITH
SOUTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS AND A SERIES OF
SHORTWAVE ENERGY IMPULSES EMANATING FROM THE BASE OF THE LOW ACROSS
THE NORTHERN AND CENTRAL PLAINS. THIS SCENARIO WOULD SUPPORT
THUNDERSTORM CHANCES THROUGHOUT THE PERIOD. BY SUNDAY MORNING THE
UPPER LOW IS FORECAST TO HAVE REACHED INTO SOUTHERN
SASKATCHEWAN...THEN MOVE SOUTHEAST ACROSS NORTH DAKOTA SUNDAY NIGHT
AND MONDAY - WITH MORE CHANCES OF SHOWERS AND THUNDERSTORMS BUT
SEVERE WEATHER NOT LIKELY.

SEASONABLE TEMPERATURES WITH HIGHS IN THE 70S TO LOWER 80S...WITH
LOWS IN THE 50S AND 60S.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 656 PM CDT MON JUN 17 2013

ONGOING SHOWERS AND THUNDERSTORMS HAVE MOVED OUT OF KBIS...AND
THOSE REMAINING AROUND KJMS WILL QUICKLY DISSIPATE AFTER SUNSET.
VFR CONDITIONS WILL BE THE RULE THEREAFTER AT ALL TAF SITES.


&&

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

$$

UPDATE...SCHECK
SHORT TERM...WAA
LONG TERM...JV
AVIATION...SCHECK