944
FXUS63 KBIS 210620
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
120 AM CDT FRI AUG 21 2026
KEY MESSAGES
- NEAR AVERAGE TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK,
WITH HIGHS MOSTLY IN THE UPPER 70S TO UPPER 80S.
- LOW TO MEDIUM CHANCES (30 TO 50 PERCENT) FOR SHOWERS AND
THUNDERSTORMS LATE SATURDAY NIGHT INTO MONDAY.
UPDATE
ISSUED AT 119 AM CDT FRI AUG 21 2026
PATCHY FOG IS TRYING TO DEVELOP FROM THE TURTLE MOUNTAINS TO
THE NORTHERN JAMES RIVER VALLEY. A MENTION OF THIS HAS BEEN
ADDED TO THE FORECAST THROUGH MID FRIDAY MORNING. UPSTREAM
SHOWERS AND THUNDERSTORMS IN SOUTHERN SASKATCHEWAN ARE TRACKING
SOUTHEASTWARD QUICKER THAN WHAT MOST GUIDANCE INDICATED, BUT
THEY ARE FAIRLY IN LINE WITH THE ARW. THE TIMING OF LOW TO
MEDIUM POPS ENTERING FAR NORTHWEST NORTH DAKOTA HAS BEEN SPED
UP BY A COUPLE HOURS. KEPT THUNDER OUT OF THE FORECAST AS
CURRENT SPC MESOANALYSIS SHOWS NO MUCAPE IN NORTHWEST NORTH
DAKOTA, BUT THERE IS ONLY 100-200 J/KG MUCAPE IN SOUTHWEST
SASKATCHEWAN WHERE LIGHTNING REMAINS PERSISTENT.
UPDATE ISSUED AT 1043 PM CDT THU AUG 20 2026
QUIET WEATHER CONTINUES ACROSS THE REGION. NO MAJOR UPDATES ARE
NEEDED AT THIS TIME.
UPDATE
ISSUED AT 542 PM CDT THU AUG 20 2026
QUIET WEATHER CONTINUES ACROSS THE AREA AS TEMPERATURES COOL
FROM THE 80S DOWN TO THE 70S. NO MAJOR UPDATES ARE NEEDED AT
THIS TIME AS THE FORECAST REMAINS ON TRACK.
DISCUSSION
ISSUED AT 231 PM CDT THU AUG 20 2026
A WEAK SHORTWAVE WITHIN NORTHWESTERLY FLOW ALOFT MAY BRING A FEW
SHOWERS TO THE AREA LATE TONIGHT THROUGH FRIDAY, OTHERWISE OVERALL
QUIET WEATHER IS EXPECTED THROUGH SATURDAY. WEST CONUS RIDGE
CURRENTLY PRODUCING SAID NORTHWESTERLY FLOW ALOFT WILL GRADUALLY
SLIDE EASTWARD THIS WEEKEND. A TROUGH SLIDING THROUGH THE RIDGE
ON SUNDAY COULD FORCE A FEW THUNDERSTORMS. WHILE GULF MOISTURE
IS SOMEWHAT CUT OFF AT THE SOURCE, ENOUGH IS STILL FAVORED TO
ADVECT INTO THE WESTERN HALF OFF THE STATE OFF MIDWESTERN
SURFACE HIGH THAT BOUNDARY LAYER DEWPOINTS WILL LIKELY RETURN TO
THE 60S. THIS COULD LEAD TO MODERATE MUCAPE VALUES IN EXCESS OF
1500 J/KG. COMBINED WITH UP TO AROUND 40 KTS OF DEEP LAYER
SHEAR, A LOW SEVERE WEATHER THREAT IS ON THE TABLE. THIS IS
SUPPORTED BY BOTH CSU MACHINE LEARNING AND THE SPC DAY 4
DISCUSSION. EVEN IF SEVERE WEATHER DOESN'T OCCUR, MORE
WIDESPREAD SCATTERED SHOWER AND THUNDERSTORM CHANCES REMAIN IN
THE FORECAST STARTING IN THE FAR WEST LATE SATURDAY NIGHT.
SHOWERS AND A FEW THUNDERSTORMS ASSOCIATED WITH AFOREMENTIONED
TROUGH MAY LINGER ACROSS MAINLY THE EASTERN HALF OF THE STATE
ON MONDAY, OTHERWISE MOSTLY DRY CONDITIONS ARE FAVORED FOR THE
FIRST HALF OF THE NEXT WORKWEEK. THOUGH A RAPID RETURN TO
NORTHWESTERLY FLOW ALOFT WILL LIKELY MEAN AN ADDITIONAL DAY OR
TWO OF AT LEAST LOW SHOWER AND/OR THUNDERSTORM CHANCES. THE
TEMPERATURE FORECAST REMAINS RELATIVELY STEADY WITH HIGHS MOSTLY
IN THE 80S THROUGH THE MIDDLE OF NEXT WEEK, THOUGH SOME MID TO
UPPER 70 DEGREE HIGHS ARE FORECAST AS WELL, ESPECIALLY ALONG
AND NORTH OF HIGHWAY 2. MONDAY IS FAVORED TO BE THE OVERALL
WARMEST DAY AS THE THERMAL RIDGE SLIDES THROUGH. THAT SAID, NBM
CLOUD COVER DOESN'T MATCH UP WITH NBM POPS WELL DURING THE
AFTERNOON, SO JUST HOW WARM MONDAY GETS WOULD BE INFLUENCED BY
LINGERING SHOWERS, THUNDERSTORMS, AND CLOUD COVER.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 119 AM CDT FRI AUG 21 2026
VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. AN
AREA OF LIGHT RAIN SHOWERS IS FORECAST TO MOVE FROM NORTHWEST
TO SOUTHEAST ACROSS THE STATE FRIDAY MORNING AND AFTERNOON.
KXWA HAS THE HIGHEST PROBABILITY OF SEEING A PERIOD OF LIGHT
RAIN, WITH LOWER PROBABILITIES AT KMOT, KBIS, AND KJMS. A
HEAVIER SHOWER COULD PRODUCE A BRIEF PERIOD OF MVFR VISIBILITY,
AND A THUNDERSTORM CANNOT BE RULED OUT IN THE AFTERNOON. LIGHT
AND VARIABLE WINDS OVERNIGHT WILL INCREASE TO AROUND 10 KTS
FRIDAY AFTERNOON WITH A NORTH TO NORTHWEST DIRECTION IN CENTRAL
NORTH DAKOTA AND A NORTHEAST TO EAST DIRECTION IN WESTERN NORTH
DAKOTA.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...HOLLAN
DISCUSSION...TELKEN
AVIATION...HOLLAN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page