725
FXUS63 KBIS 121157
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
657 AM CDT WED AUG 12 2026
KEY MESSAGES
- SCATTERED SHOWERS AND THUNDERSTORMS TODAY AND TONIGHT.
ISOLATED SEVERE STORMS ARE POSSIBLE ALONG AND SOUTH OF THE
HIGHWAY 200 CORRIDOR THIS AFTERNOON INTO THIS EVENING.
- A COOLING TREND IS EXPECTED THROUGH FRIDAY, FOLLOWED BY A
WARMING TREND THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
UPDATE
ISSUED AT 621 AM CDT WED AUG 12 2026
PARTLY CLOUDY SKIES ACROSS WESTERN AND CENTRAL ND THIS MORNING.
EXPECT INCREASING MID AND HIGH CLOUDS TODAY. ONLY SOME MINOR
ADJUSTMENTS TO TRIM BACK POPS THIS MORNING AND ADJUSTED SKY
COVER SOME.
DISCUSSION
ISSUED AT 251 AM CDT WED AUG 12 2026
CURRENTLY, ISOLATED THUNDERSTORMS WERE LOCATED OVER SOUTH
CENTRAL ND. THIS IS WITHIN AN AREA OF 2000 J/KG OF INSTABILITY
ALOFT WITH MODERATE TO STRONG EFFECTIVE SHEAR. THE LATEST WV
IMAGERY AND UPPER LEVEL HEIGHTS SHOW AN UPPER LEVEL TROUGH OVER
THE PACIFIC NORTHWEST WITH A MEAN UPPER LEVEL RIDGE OVER CENTRAL
MONTANA. A SPEED MAX WAS LOCATED OVER EASTERN MONTANA WITH SOUTH
CENTRAL ND IN THE LEFT FRONT QUAD OF THE SHORTWAVE. THIS IS
ENOUGH FORCING TO CONTINUE TO DEVELOP ISOLATED TO SCATTERED
THUNDERSTORMS OVER SOUTH CENTRAL ND, WITH THE INSTABILITY ALOFT.
FOR TODAY, AS THIS SPEED MAX PUSHED EAST THROUGH THE STATE,
THINK THERE MAY BE A CONTINUED THREAT OF SHOWERS AND
THUNDERSTORMS THROUGH THE DAY. SPC HAS PLACED A MARGINAL RISK OF
SEVERE STORMS MAINLY ALONG AND SOUTH OF THE HIGHWAY 200
CORRIDOR TODAY. CAN'T REALLY ARGUE WITH THIS AS THE ONE THING
THAT SEEMS MOST CERTAIN THIS MORNING IS THE INSTABILITY TODAY IS
FORECAST TO BE MUCH LOWER NORTH OF THE HIGHWAY 200 CORRIDOR.
THERE MAY STILL BE SHOWERS OR A FEW THUNDERSTORMS, BUT RIGHT NOW
FORECAST SOUNDINGS DON'T SUPPORT SEVERE STORMS IN THE NORTH. AS
YOU GET SOUTH OF THE HIGHWAY 200 CORRIDOR, THINGS GET MUDDLED
PRETTY QUICKLY.
THE SOUTHWEST AND SOUTH CENTRAL LOOK TO BE THE MOST UNSTABLE
THIS AFTERNOON WITH 1500-3000 J/KG OF MUCAPE. SHEAR IS
SUFFICIENT AT AROUND 40 KNOTS, BUT INCREASES AS YOU GO NORTH
FROM SOUTHERN INTO CENTRAL AND NORTHERN ND. THERE ARE A FEW
LIMITING FACTORS. WITH THE AFOREMENTIONED SHORTWAVE THERE WILL
BE MORE CLOUDS AROUND TODAY. THE RAP ALSO INDICATES THE
POTENTIAL FOR SOME STRATUS TODAY OVER THE SOUTHERN HALF OF THE
CWA, WHICH COULD LIMIT INSTABILITY. IN GENERAL, THE INSTABILITY
MAY NOT BE AS GREAT AS YESTERDAY, WHEN WE HAD HIGHS IN THE UPPER
80S AND DEW POINTS IN THE MID AND UPPER 60S IN SOUTHWEST AND
SOUTH CENTRAL ND. TODAY WE ARE EXPECTING HIGHS IN THE LOWER TO
MID 80S WITH DEW POINT IN THE LOW TO MID 60S. HOWEVER,
INSTABILITY WILL BE SUFFICIENT AND WITH THE MODERATE TO STRONG
SHEAR, WE WILL HAVE THE POTENTIAL FOR STRONG TO SEVERE STORMS
THIS AFTERNOON INTO THIS EVENING. THE MAIN QUESTION IS WHERE AND
WHEN. WITH THE SHORTWAVE MOVING THROUGH WE SEE CONTINUED
CONVECTION OVER THE SOUTH CENTRAL EARLY THIS MORNING, AND THIS
MAY SPREAD NORTH AND EAST TODAY. THEN AS THE RRQ OF THE
SHORTWAVE MOVES ACROSS THE AREA LATER TODAY, THIS MAY PROVIDE
THE FORCING FOR ASCENT NEEDED TO INITIATE CONVECTION. THE
INTERFACE OF THE STRONG INSTABILITY TO THE SOUTH AND THE STRONG
SHEAR TO THE NORTH WOULD BE AN IDEAL AREA FOR SEVERE CONVECTION
TODAY. THE MAIN HAZARDS BEING LARGE HAIL TO GOLFBALL SIZE AND
WINDS TO 60 MPH, IF WE CAN GET A SUSTAINED UPDRAFT. THE FAR
SOUTHWEST WILL BE THE MOST UNSTABLE AND CONVECTION DEVELOPING
OVER SOUTHEAST MONTANA MAY MOVE INTO SOUTHWEST ND. THE
ENVIRONMENT WOULD BE FAVORABLE FOR QUICK DEVELOPMENT WITH STEEP
LAPSE RATES. WITH A BROAD SOUTHWEST UPPER FLOW, IT'S HARD TO SAY
WHERE AND WHEN CONVECTION MAY DEVELOP AND CAMS ARE BOUNCING
AROUND A BIT. NEVERTHELESS, THERE WILL BE A THREAT FOR STRONG TO
SEVERE STORMS TODAY.
ONCE CONVECTION ENDS TODAY/THIS EVENING, WE COOL DOWN A BIT FOR
THURSDAY AND ESPECIALLY FRIDAY. WE REMAIN IN A FAVORABLE
SOUTHWEST UPPER FLOW OVER THE FAR WEST ON THURSDAY, THEN
EVENTUALLY ACROSS THE AREA FRIDAY, BUT WITH LESS INSTABILITY,
THE THREAT FOR STRONG TO SEVERE STORMS WILL BE LOW. CURRENTLY
SPC HAS ONLY GENERAL THUNDERSTORMS FORECAST FOR THURSDAY AND
FRIDAY. AFTER FRIDAY WE BEGIN A SLOW WARMING TREND THROUGH THE
WEEKEND AND INTO NEXT WEEK. SATURDAY AND SUNDAY MAY END UP BEING
MOSTLY DRY BEFORE NEAR DAILY CHANCES FOR THUNDERSTORMS RETURN
EARLY NEXT WEEK.
AVIATION /12Z TAFS THROUGH 12Z THURSDAY/
ISSUED AT 621 AM CDT WED AUG 12 2026
VFR CONDITIONS TO BEGIN THE 12Z TAF PERIOD. THERE IS SOME PATCHY
FOG AROUND BUT NOT CURRENTLY AT TAF SITES. FOG SHOULD DISSIPATED
MOST AREAS PRETTY QUICKLY THIS MORNING. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED AGAIN THIS AFTERNOON INTO THIS
EVENING ACROSS WESTERN AND CENTRAL ND. ANY THUNDERSTORMS WILL
CONTAIN GUSTY AND ERRATIC WINDS WITH THE POTENTIAL FOR MVFR TO
IFR VISIBILITIES.
KDIK COMMUNICATION PROBLEMS CONTINUE. INCLUDED AMD NOT SKED.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...TWH
DISCUSSION...TWH
AVIATION...TWH
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