031
FXUS63 KBIS 220708
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
208 AM CDT FRI MAY 22 2026
KEY MESSAGES
- SCATTERED TO NUMEROUS SHOWERS CONTINUE ACROSS THE WESTERN
HALF OF THE STATE THROUGH FRIDAY AFTERNOON. AN AREA OF MORE
PERSISTENT RAINFALL MOVES UP FROM THE SOUTH OVER CENTRAL AND
EASTERN NORTH DAKOTA LATE FRIDAY MORNING THROUGH FRIDAY
EVENING.
- BELOW AVERAGE TEMPERATURES FRIDAY, THEN WARMING TO WELL ABOVE
AVERAGE BY THE END OF THE HOLIDAY WEEKEND.
UPDATE
ISSUED AT 206 AM CDT FRI MAY 22 2026
OVER THE LAST FEW HOURS, AN OUTFLOW BOUNDARY ORIGINATING FROM
EVENING CONVECTION IN SOUTHWEST NORTH DAKOTA HAS BEEN SPARKING
SCATTERED SHOWERS AND UNTIL RECENTLY, ISOLATED THUNDERSTORMS OVER
SOUTH CENTRAL NORTH DAKOTA, NOW SHIFTING TOWARDS NORTH CENTRAL
NORTH DAKOTA. THIS ACTIVITY IS NOT BEING HANDLED WELL BY RAPID
REFRESH GUIDANCE, SO HAVE RELIED HEAVILY ON OBSERVED TRENDS FOR
UPDATES TO THE POP FORECAST. RECENT CAMS ARE ALSO STRUGGLING
WITH THE WESTERN EXTENT OF RAIN, AS WELL AS THE OVERALL COVERAGE
OF RAIN SHOWERS (MODELS ARE TOO LOW/SPARSE).
UPDATE
ISSUED AT 939 PM CDT THU MAY 21 2026
A RELATIVELY NARROW LINE OF SHOWERS AND THUNDERSTORMS CONTINUES
MAINLY FROM HETTINGER TO RICHARDTON TO JUST WEST OF MINOT. AS
HAS BEEN EXPECTED, THUNDERSTORM ACTIVITY HAS REALLY DECREASED
OVER THE PAST HOUR OR SO AS THE SUN SET. THIS TREND IS EXPECTED
TO CONTINUE, THOUGH SUSPECT ISOLATED THUNDERSTORMS WILL REMAIN
POSSIBLE UNTIL MIDNIGHT AND POSSIBLY THROUGH THE NIGHT. WITH
WEAK MID-LEVEL WINDS, STORM MOTION HAS BEEN ERRATIC TO SAY THE
LEAST WITH INDIVIDUAL CELL MOVEMENTS OFTEN SEEMING TO
CONTRADICT ONE ANOTHER. OVERALL THOUGH, THE AXIS OF HEAVIEST
RAIN HAS REMAINED RELATIVELY STABLE AS ONE WOULD EXPECT WITH
THE STATIONARY FRONT.
UPDATE
ISSUED AT 717 PM CDT THU MAY 21 2026
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ALONG A STATIONARY
FRONTAL BOUNDARY OVER PARTS OF SOUTHWESTERN NORTH DAKOTA, AND
TO A LESSER EXTENT, PARTS OF THE NORTH CENTRAL. A STRONG STORM
HAD INITIALLY DEVELOPED SOUTHWEST OF DICKINSON, THOUGH HAS
SINCE DECREASED IN INTENSITY. MODEL GUIDANCE SUGGESTS
INSTABILITY SHOULD RAPIDLY DECREASE AS THE SUN SETS RESULTING
MOSTLY IN SHOWERS DURING THE OVERNIGHT HOURS. THOUGH A FEW
RUMBLES OF THUNDER CANNOT BE COMPLETELY RULED OUT. SHOWER
ACTIVITY OVERNIGHT WILL REMAIN MOSTLY CONCENTRATED ALONG THE
FRONTAL BOUNDARY BEFORE EXPANDING EASTWARD FRIDAY.
DISCUSSION
ISSUED AT 230 PM CDT THU MAY 21 2026
CURRENTLY A MEDIUM SIZE TROUGH AND UPPER LOW IS SITTING OVER
MONTANA AND WYOMING. UPSTREAM IN THE PACIFIC NORTHWEST A RIDGE
OR ZONAL FLOW IS FORMING. AT THE SURFACE THE COLLOCATED SURFACE
LOW IS IN SOUTHERN CANADA, WITH A STATIONARY FRONT SITTING IN
AN INVERTED TROUGH PLACED OVER WESTERN NORTH DAKOTA. ALONG THE
POSITIVE VORTICITY SIDE OF THE UPPER LEVEL TROUGH IN EASTERN
MONTANA, SHOWERS HAVE BEEN ON GOING. THIS AFTERNOON AS SURFACE
TEMPERATURES INCREASE, AROUND 1500 J/KG OF CAPE WILL BE PRESENT
ALONG THE FRONT. WITH SHEAR AROUND 30KTS, THUNDERSTORMS WILL
FORM AND TRAIN SOUTH TO NORTH ALONG THE FRONT SINCE THE SHEAR
VECTOR WILL BE PARALLEL TO THE FRONT. WITH VERY SKINNY CAPE
PROFILES AND HIGH RELATIVE HUMIDITIES THROUGH THE UPPER LEVELS,
THERE IS ONLY A SMALL CHANCE OF SEVERE HAZARDS. SO THE HIGHEST
RISK FROM THE STORMS WILL BE HEAVY DOWNPOURS. THE CAMS AGREE ON
THE LOCATION BEING SOMEWHERE BETWEEN BEACH, AND GLEN ULLIN.
TIMING LOOKS TO BE BETWEEN 5 AND 7PM CT. WITH THE FRONT
REMAINING STATIONARY ALONG WITH THE INVERTED TROUGH, THE STORMS
SHOULD STAY WEST OF THE MISSOURI RIVER THROUGH THE EVENING.
TONIGHT A SURFACE LOW MOVING OUT OF WYOMING FROM THE BOTTOM OF
THE UPPER LEVEL TROUGH WILL START TO MOVE NORTHEAST. BY FRIDAY
MORNING IT WILL FORM INTO IT'S OWN STACKED LOW AND BE IN
NORTHERN SOUTH DAKOTA. THEREFOR FRIDAY WILL BE SLIGHTLY COOLER
WITH WIDESPREAD RAIN ACROSS MOST OF THE STATE. THIS RAIN WILL
LAST THROUGH MOST OF THE DAY, ENDING WEST TO EAST AS THE LOW
CONTINUES INTO NORTHERN MINNESOTA FRIDAY NIGHT. AN AXIS OF
HIGHER QPF IS WILL OCCUR WITH THE THUNDERSTORMS THIS EVENING,
AND THE FRONT ENHANCING LIFT THROUGH FRIDAY IN WESTERN ND. THERE
IS A MEDIUM TO HIGH CHANCE OF 1 INCH OF QPF ON A NORTH SOUTH
LINE CENTERED ON DICKINSON BETWEEN SOUTH DAKOTA AND NEW TOWN.
ANOTHER HIGHER AREA OF QPF IS FORECAST IN SOUTHEAST ND WHEN THE
LOW WRAPS UP AND MOVES THROUGH. THE MAJORITY OF THAT QPF WILL
FALL FRIDAY AFTERNOON.
THROUGH THIS WEEKEND ZONAL FLOW WILL SETUP ACROSS THE NORTHERN
PLAINS LEADING TO VERY WARM TEMPERATURES, BOTH ALOFT AND AT THE
SURFACE. BY MONDAY EXPECT HIGHS NEAR 90 IN THE WEST AND
CENTRAL. THESE ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH
THE WEEK. IN THE LATTER PART OF NEXT WEEK A LARGE UPPER LEVEL
LOW COULD MOVE THROUGH, ALTHOUGH THERE IS AN INCREDIBLE AMOUNT
OF UNCERTAINTY IN LOCATION AND TIMING IF IT DOES OCCUR. NBM DOES
HAVE LOW POPS FOR THIS, AND TEMPERATURES LOOK TO STAY IN THE
UPPER 70S OR LOWER 80S.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 206 AM CDT FRI MAY 22 2026
SCATTERED TO NUMEROUS SHOWERS WILL CONTINUE ACROSS MUCH OF THE
WESTERN HALF OF THE STATE THROUGH FRIDAY. A SEPARATE AREA OF
RAIN WILL EXPAND NORTHWARD FROM SOUTH DAKOTA INTO THE EASTERN
HALF OF THE STATE DURING THE DAY FRIDAY. THE WIDESPREAD RAIN IS
FORECAST TO DIMINISH FROM SOUTHWEST TO NORTHEAST FRIDAY EVENING.
EXPECT PERIODS OF MVFR TO IFR VISIBILITY WITH HEAVIER SHOWERS
AND MORE PERSISTENT AREAS OF RAIN. THE RISK FOR THUNDERSTORMS
FOR THE REST OF THE NIGHT THROUGH FRIDAY MORNING IS VERY LOW. A
LOW CHANCE OF WEAKER THUNDERSTORMS RETURNS TO CENTRAL NORTH
DAKOTA FRIDAY AFTERNOON.
CEILINGS ARE FORECAST TO FALL TO MVFR LEVELS FROM SOUTHWEST
NORTH DAKOTA TO BETWEEN KXWA AND KMOT BY MID FRIDAY MORNING,
WITH IFR POSSIBLE AT KDIK. BY LATE FRIDAY MORNING, LOW CEILINGS
SHOULD BEGIN EXPANDING OVER KBIS (PREVAILING MVFR) AND KJMS
(MVFR LOWERING TO IFR). KMOT COULD SEE A SHORTER PERIOD OF MVFR
CEILINGS MID TO LATE FRIDAY MORNING BEFORE PREVAILING MVFR
ARRIVES FRIDAY EVENING. MEANWHILE, KXWA COULD MAINTAIN A VFR
CEILING THROUGH THE FORECAST PERIOD.
PREVAILING WINDS ON FRIDAY WILL GENERALLY BE NORTHERLY AROUND 5-10
KTS IN WESTERN NORTH DAKOTA TO EASTERLY AROUND 10-15 KTS IN CENTRAL
AND EASTERN NORTH DAKOTA.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...HOLLAN
DISCUSSION...SMITH
AVIATION...HOLLAN
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