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000
FXUS63 KBIS 140829
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
329 AM CDT FRI JUN 14 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI JUN 14 2013

MAIN FORECAST CONCERNS ARE PRECIPITATION COVERAGE/TIMING AND CONVECTIVE
POTENTIAL. WV IMAGERY SHOWED TROUGH AXIS OVER INTER-MOUNTAIN WEST
AND RIDGE AXIS ENTERING MINNESOTA...LEAVING NORTHERN PLAINS IN
SOUTHWEST DIFLUENT FLOW. SURFACE ANALYSIS SHOWED ELONGATED LOW
PRESSURE CENTERED IN VICINITY OF MT/SD/ND BORDER. AREA OF
THUNDERSTORMS WAS MOVING THROUGH EAST CENTRAL MONTANA AND ABOUT TO
ENTER NORTH DAKOTA AS OF 0830Z. 00Z NAM INITIALIZED THIS FAIRLY
WELL...MOVING IT NORTHEAST AND ACROSS OUR NORTHWEST CWA. THIS
AREA HAS HIGHEST POPS FOR THE EARLY MORNING AREAS. NAM ALSO PICKED
UP ANOTHER AREA OF ISOLATED/SCATTERED THUNDERSTORMS NEAR RAPID
CITY THAT IT BRINGS INTO SOUTHWEST AND SOUTH CENTRAL ND. THIS
SECOND AREA HAS REMAINED SOMEWHAT DISORGANIZED AND MAY NOT IMPACT
SOUTH CENTRAL ND.

WITH REGARD TO CONVECTIVE POTENTIAL ON FRIDAY...DESPITE SURFACE
BASED CAPE APPROACHING 1000 J/KG AHEAD OF THE COLD FRONT THAT WILL
BE ACROSS CENTRAL ND BY 18Z...FORECAST SOUNDINGS INDICATE A
SUBSTANTIAL WARM LAYER/CAP ALOFT THAT SHOULD SUPPRESS CONVECTIVE
POTENTIAL. SPC HAS ALSO REMOVED SLIGHT RISK OF SEVERE AREA FROM
MOST OF EASTERN NORTH DAKOTA. CONSEQUENTLY...MENTION OF THUNDER
HAS BEEN LESSENED IN THE FORECAST AND SEVERE WORDING REMOVED. AS
FRONT PROGRESSES EASTWARD WINDS WILL SHIFT TO THE WEST AND BECOME
GUSTY AT TIMES BEHIND THE FRONT. PRECIP SHOULD CLEAR EASTERN ZONES
BY EARLY EVENING WITH CLEARING FROM WEST TO EAST DURING THE DAY.
DRY CONDITIONS EXPECTED OVERNIGHT WITH CLOSED LOW PRESSURE SYSTEM
LOCATED OVER CENTRAL SASKATCHEWAN AND COLD FRONT INTO CENTRAL MN
BY 12Z SAT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI JUN 14 2013

A DRY AND BREEZY DAY IS EXPECTED ON SATURDAY AS THE UPPER LEVEL LOW
THAT LIFTED THROUGH MONTANA IS SITUATED OVER SASKATCHEWAN. ALTHOUGH
THE SURFACE GRADIENT IS NOT STRONG...WITH ABUNDANT SUNSHINE THE
BOUNDARY LAYER SHOULD WARM SUFFICIENTLY THAT WINDS AROUND 750-800MB
WILL BE ABLE TO MIX DOWN TO THE SURFACE. WINDS WILL BE STRONGEST
ACROSS THE NORTH WITH SUSTAINED WINDS OF 20 TO 25 KNOTS DIMINISHING
TO 15 TO 20 KNOTS ACROSS THE SOUTH.

THE UPPER LOW THEN DROPS SOUTHEAST ACROSS THE NORTHEAST THIRD OF THE
CWA ON SUNDAY...ALLOWING FOR ENOUGH COOLING ALOFT TO DEVELOP
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE NORTHERN AND EASTERN
PORTIONS OF THE FORECAST AREA.

UPPER LEVEL RIDGING PUSHES INTO THE NORTHERN ROCKIES ON MONDAY AHEAD
OF ANOTHER UPPER LOW OFF THE NORTHWEST U.S. COAST. MODELS DEPICT A
SHORTWAVE SLIDING DOWN THE UPPER RIDGE...ACROSS CENTRAL NORTH
DAKOTA. MOISTURE WILL BE LIMITED BUT WITH DAYTIME HEATING A FEW
SHOWERS OR THUNDERSTORMS CANNOT BE RULED OUT.

MONDAY NIGHT AND TUESDAY NIGHT...UPPER RIDGING BUILDS EASTWARD INTO
THE NORTHERN PLAINS WHICH SHOULD KEEP A THE THREAT OF SHOWERS AND
STORMS TO A MINIMUM.

WEDNESDAY AND WEDNESDAY NIGHT...THE UPPER LOW MOVES SLOWLY
EAST AND SHORTWAVE ENERGY ROUNDS THE BASE OF THE LOW ALLOWING
SOUTHWEST UPPER FLOW TO MOVE INTO THE WESTERN DAKOTAS. WITH THE
UPPER RIDGE STILL OVER THE DAKOTAS...THUNDERSTORMS ACTIVITY WILL BE
LIMITED...BUT WITH INCREASING LOW LEVEL MOISTURE AND RISING DAYTIME
TEMPERATURES...DIURNALLY DRIVEN THUNDERSTORMS CANNOT BE RULED OUT
WEDNESDAY AFTERNOON AND EVENING.

THURSDAY AND THURSDAY NIGHT...AS THE RIDGE AXIS FINALLY MAKES ITS
WAY EAST ACROSS THE FORECAST AREA...THUNDERSTORM CHANCES WILL
INCREASE AS A MORE FAVORABLE SHEAR ENVIRONMENT SHIFTS INTO THE
DAKOTAS.

TEMPERATURES REMAIN SEASONABLE THROUGH THE PERIOD WITH MAINLY 70S
FOR HIGHS AND 50S FOR LOWS SATURDAY THROUGH MONDAY...WE DO WARM UP A
BIT LATER IN THE EXTENDED PERIOD WITH HIGHS APPROACHING THE LOWER
80S AND MORNING LOWS AROUND 60.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 121 AM CDT FRI JUN 14 2013

MAINLY VFR CONDITIONS EXPECTED AT TAF SITES ALTHOUGH BRIEF MVFR
CONDITIONS COULD DEVELOP IN ANY SHOWERS...ISOLATED THUNDERSTORMS
AND ASSOCIATED LOWER CEILINGS. WINDS WILL TURN OUT OF THE WEST AS
A COLD FRONT MOVES ACROSS THE STATE TODAY.


&&

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

$$

SHORT TERM...JNS
LONG TERM...TWH
AVIATION...JNS