632
FXUS63 KBIS 030623
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
123 AM CDT FRI JUL 3 2026
KEY MESSAGES
- SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED TONIGHT PRIMARILY
OVER NORTHWEST NORTH DAKOTA. THE MAIN EXPECTED HAZARDS
INCLUDE HAIL TO THE SIZE OF GOLF BALLS AND DAMAGING WINDS TO
70 MPH.
- LOW TO MEDIUM CHANCES FOR SHOWERS AND THUNDERSTORMS FRIDAY
THROUGH FRIDAY NIGHT, WITH A RISK FOR ISOLATED SEVERE
THUNDERSTORMS. LOW SHOWER AND THUNDERSTORM CHANCES REMAIN IN
THE FORECAST AT TIMES THROUGH THE HOLIDAY WEEKEND, WITH
CHANCES INCREASING SUNDAY NIGHT.
- HIGHS MAINLY IN THE 80S EXPECTED THROUGH INDEPENDENCE DAY,
WITH 90S ON SUNDAY.
UPDATE
ISSUED AT 1217 AM CDT FRI JUL 3 2026
** MESOSCALE DISCUSSION **
STORM INTENSITY HAS GRADUALLY BEEN WANING IN WESTERN ND IN THE
LAST 60 MINUTES, AS EXPECTED, BUT SEVERAL CLUSTERS OF STORMS
PERSIST AS OF 04Z IN WEST CENTRAL/NORTHWESTERN ND AND EASTERN
MT. MLCIN IS GRADUALLY INCREASING AND RESULTING IN CONVECTION
GRADUALLY BECOMING MORE ELEVATED VERSUS BOUNDARY-LAYER-BASED.
NONETHELESS, STEEP MIDLEVEL LAPSE RATES AND A SUFFICIENTLY-DEEP
MOIST LAYER ARE CONTRIBUTING TO 1500-2000 J/KG OF MUCAPE AMID
SUFFICIENT EFFECTIVE-LAYER SHEAR FOR ORGANIZED CONVECTION. WE
DO EXPECT STORM INTENSITY TO CONTINUE TO GRADUALLY WANE IN THE
ABSENCE OF STRONGER LARGE-SCALE FORCING AND AS MLCIN CONTINUES
ITS DIURNAL INCREASE. HOWEVER, THE TERMINUS OF AN ~30 KT LOW-
LEVEL JET IS FOCUSED IN WEST CENTRAL/NORTHWEST ND AND WILL AID
IN SOME MAINTENANCE OF CONVECTION, AND THE OVERALL MUCAPE/SHEAR
COMBINATION WILL FAVOR A MARGINAL SEVERE-STORM RISK CONTINUING
IN PARTS OF WEST CENTRAL, NORTHWEST, AND NORTH CENTRAL ND FOR
THE NEXT 1-3 HOURS. CAMS SUPPORT CONTINUED GRADUAL WEAKENING AND
LESSENING OF THE RISK OVERNIGHT, THOUGH, JUST AS WE EXPECT AT
THIS TIME.
CJS
UPDATE
ISSUED AT 932 PM CDT THU JUL 2 2026
** MESOSCALE DISCUSSION **
SCATTERED STRONG-SEVERE THUNDERSTORMS INCLUDING SEVERAL
SUPERCELLS HAVE EVOLVED OVER WESTERN ND IN THE PAST HOUR. THESE
STORMS ARE IN AN ENVIRONMENT CHARACTERIZED BY AROUND 2000 J/KG
AND 40-45 KT OF EFFECTIVE-LAYER SHEAR. HODOGRAPHS IN SOUTHWEST
ND FAVOR SPLITTING SUPERCELLS WITH BOTH LEFT-MOVING AND RIGHT-
MOVING SUPERCELLS ALLOWED TO PERSIST. HODOGRAPHS FURTHER NORTH
IN NORTHWEST AND WEST CENTRAL ND HAVE A BIT MORE CURVATURE IN
THEIR LOWEST 1 KM, SUGGESTING RIGHT-MOVING SUPERCELLS MAY BE A
BIT MORE FAVORED IN THAT AREA. REGARDLESS, THE WELL-ESTABLISHED
MESOCYCLONES ARE EXPECTED TO PERSIST THE NEXT 1-2 HOURS EVEN AS
MLCIN GRADUALLY INCREASES. SURFACE DEWPOINTS HAVE INCREASED INTO
THE LOWER 60S F, THOUGH, WHICH IS HIGHER THAN RAP-BASED/SPC
OBJECTIVE MESOANALYSIS. THAT MAY OFFSET INCREASES IN MLCIN AND
ALLOW SOME OF THE SUPERCELLS TO PERSIST EVEN A BIT LONGER THAN
THEY OTHERWISE WOULD ALONE.
UPSTREAM IN SOUTHERN SASKATCHEWAN, A LINEAR CONVECTIVE COMPLEX
HAS BEEN ORGANIZING. FORWARD-PROPAGATING MCS MOTION VECTORS DO
SUGGEST THIS MAY EVENTUALLY MOVE INTO NORTHWEST AND NORTH
CENTRAL ND IN THE NEXT FEW HOURS, WITH AN ATTENDANT SEVERE-
STORM RISK, MUCH LIKE RECENT HRRR SIMULATIONS HAVE SHOWN.
UPDATE
ISSUED AT 538 PM CDT THU JUL 2 2026
** MESOSCALE DISCUSSION **
THE SEVERE-STORM RISK IS GRADUALLY INCREASING OVER PARTS OF
WESTERN ND, THOUGH SOME UNCERTAINTY REMAINS IN ITS EVOLUTION.
LARGE HAIL UP TO GOLF BALL SIZE AND DAMAGING WIND GUSTS UP TO 70
MPH ARE THE MAIN CONCERNS WITH SEVERE STORMS THIS EVENING.
AS OF 2230Z, VISIBLE SATELLITE IMAGERY SHOWS PERSISTENT
ATTEMPTS AT CONVECTIVE INITIATION NEAR GLENDIVE AND WIBAUX
MONTANA. THE BACKGROUND ENVIRONMENT FEATURES WEAK FORCING FOR
ASCENT WITH NEUTRAL TO SLIGHT HEIGHT RISE TENDENCIES ALOFT, AND
GENERALLY-WEAK SURFACE CONVERGENCE. THAT SAID, THERE IS BROAD
SURFACE CONFLUENCE APPARENT IN EAST CENTRAL MT, WHICH MAY BE
ENOUGH TO ALLOW THE CONVECTIVE INITIATION TO BECOME SUSTAINED IN
THAT AREA. WHILE THE BEACH AWOS SUGGESTS THE LOW-LEVEL MOISTURE
IMMEDIATELY ALONG THE ND/MT BORDER MAY BE SHALLOW, THE OBSERVED
TEMPERATURES IN THE MID 80S F ARE SUFFICIENT FOR MLCIN TO BE
MINIMIZED PER MODIFICATIONS TO THE 18Z KBIS RAOB AND RECENT
MODIFIED RAP SOUNDINGS IN SOUTHWESTERN ND. IF THIS CONVECTION
CAN BE SUSTAINED IN THE NEXT 30-60 MINUTES, OVERCOMING ANY
RESIDUAL (EVEN IF SLIGHT) WARM NOSE ALOFT, WE WOULD EXPECT IT TO
BECOME SUPERCELLULAR AND MOVE INTO SOUTHWESTERN ND, PARTICULARLY
INTO GOLDEN VALLEY AND BILLINGS COUNTIES IN THE NEXT 1-2 HOURS.
THIS IS A CONDITIONAL SCENARIO, BUT THE CAPE-SHEAR SETTING AND
STEEP LOW- AND MIDLEVEL LAPSE RATES WOULD BE FAVORABLE FOR
LARGE HAIL AND DAMAGING WINDS IF THIS COMES TO FRUITION. IT'S
POSSIBLE THAT EVEN IF A STORM BECOMES SUSTAINED, THAT IT WOULD
TAKE IT TIME AND FURTHER-EASTWARD REACH INTO SOUTHWESTERN ND BY
A COUNTY OR TWO IN ORDER TO INTERCEPT SOMEWHAT RICHER LOW-
LEVEL MOISTURE AND INTENSIFY FURTHER. THAT IS IDENTIFIED BY
DEWPOINTS IN THE UPPER 50S TO LOWER 60S F IN THE DICKINSON AND
SURROUNDING AREAS.
OTHERWISE, SOME CAMS HAVE SIGNALED THE STORMS IN NORTHWESTERN SD
COULD MOVE INTO SOUTHWESTERN ND, BUT THIS WOULD LIKELY DEPEND
ON OR BE A RESULT OF LEFT-SPLIT SUPERCELLS GIVEN MEAN WINDS AND
SUPERCELL-MOTION VECTORS. FORECAST HODOGRAPHS DO FAVOR SPLITTING
SUPERCELLS IN NORTHWESTERN SD, BUT ONLY THE LEFT-MOVING VECTORS
FAVOR PROPAGATION OF THIS PARTICULAR ACTIVITY INTO SOUTHWESTERN
ND. THIS MAY PROVIDE AN ISOLATED SEVERE-STORM RISK IN PARTS OF
BOWMAN, ADAMS, AND SURROUNDING COUNTIES IN THE NEXT 1-3 HOURS,
AS WELL.
FINALLY, THERE ARE STORMS GRADUALLY INTENSIFYING IN SOUTHERN
SASKATCHEWAN AND NORTHEASTERN MT WITH A MORE WELL-DEFINED
IMPULSE AND RELATED ASCENT ALOFT. THESE STORMS MAY IMPACT PARTS
OF NORTHWESTERN ND WITH AN ASSOCIATED SEVERE-STORM RISK BY MID
TO LATE EVENING, AND WILL BE MONITORED CLOSELY IN THE COMING
HOURS TO IDENTIFY THEIR ASSOCIATED TRENDS.
DISCUSSION
ISSUED AT 106 PM CDT THU JUL 2 2026
ONGOING CONVECTION ALONG THE I-94 CORRIDOR FROM BISMARCK TO
JAMESTOWN WILL PROBABLY FESTER THROUGH THE AFTERNOON. WOFS IS
NOT IMPRESSED WITH THE SEVERE POTENTIAL HERE, AND NEITHER ARE
WE, ALTHOUGH AN ISOLATED MARGINAL SEVERE HAILSTONE CAN NOT BE
RULED OUT. BULK SHEAR HAS INCREASED HERE IN THE PAST HOUR AND
THERE IS A LARGE INCREASING GRADIENT IN HAIL CAPE FROM JAMESTOWN
TO BISMARCK. I THINK THE MAIN CONCERN IS NOW SHIFTING MORE TO
THE WEST. NEAR FULL SUN AND INCREASING SHEAR AND INSTABILITY IS
EXPECTED ACROSS WESTERN ND THIS AFTERNOON, BUT THERE IS STILL
DISAGREEMENT IN THE CAMS AS TO WHEN CONVECTION WILL DEVELOP WITH
SOME DEVELOPING CONVECTION EARLY-MID AFTERNOON AND OTHERS
HOLDING OFF UNTIL CLOSER TO 00Z FRIDAY. THE WOFS IS SHOWING
CONVECTION DEVELOPING IN THE FAR WEST AROUND 21-22 UTC.
STORM MODE WOULD SUPPORT SUPERCELLS OVER WESTERN ND THIS
AFTERNOON AND ALL HAZARDS WOULD BE IN PLAY THEN. LCL HEIGHTS ARE
PRETTY HIGH THOUGH SO THE THREAT IN THE FAR SOUTHWEST TO WEST
CENTRAL LOOKS LOWER THAN IN THE NORTHWEST LATE AFTERNOON INTO
EARLY EVENING. THERE IS ALSO A SMALL MAX IN THE FAR SOUTH
CENTRAL EARLY THIS EVENING, BUT OVERALL THE TORNADO THREAT
REMAINS ON THE LOWER SIDE. ALSO LARGE TO VERY LARGE HAIL WOULD
BE A THREAT WITH SUPERCELLS THAT CAN MAINTAIN THEIR UPDRAFTS. A
TRANSITION TO A LINEAR SYSTEM MAY STILL OCCUR LATER TONIGHT
ALTHOUGH THE SIGNAL FOR THIS HAS NOT BEEN CONSISTENT AND IT HAS
BACKED OFF FROM YESTERDAY. SPC HAS PULLED THE ENHANCED AREA OUT
OF THE JAMES RIVER VALLEY. YESTERDAY, CONVECTION FIRING OUT WEST
OR ALONG THE EAST TO WEST BOUNDARY OVER CENTRAL/SOUTHERN ND
TRANSITIONED INTO ONE OR MORE LINEAR CONVECTIVE SYSTEMS THAT
TRACKED INTO SOUTHEAST ND. THAT'S NOT REALLY SHOWING UP TODAY.
ALTHOUGH A SMALLER LINEAR OR BOWING SEGMENT FROM ANY CONVECTION
THAT FIRES OVER WESTERN ND CAN NOT BE RULED OUT. THERE HAS BEEN
SOME CONSISTENCY IN CONVECTION LATER THIS EVENING/OVERNIGHT
EITHER DEVELOPING OVER OR MOVING INTO NORTHWEST ND (FROM MONTANA
OR SASKATCHEWAN) AND TRACKING INTO THE NORTH CENTRAL. WE WILL
CONTINUE TO MONITOR, BUT OVERALL VERY PERPLEXING WITH LITTLE
AGREEMENT IN THE CAMS. ALSO DO NOT WANT TO DOWNPLAY THE SEVERE
POTENTIAL IF/WHEN CONVECTION DOES DEVELOP. ALTHOUGH THE BULK
SHEAR DOES NOT APPEAR TO BE AS STRONG, AND THERE ARE SOME
LIMITING FACTORS SUCH AS THE UPPER LEVEL RIDGING MENTIONED IN A
PRIOR DISCUSSION, THE POTENTIAL FOR SEVERE STORMS DOES REMAIN
AND IF YOU DO HAVE PLANS THAT TAKE YOU OUTDOORS, REMAIN WEATHER
AWARE AND BE READY TO TAKE SHELTER IF THREATENING WEATHER
APPROACHES.
FRIDAY MAY BE ANOTHER DAY SIMILAR TO TODAY, WITH LITTLE
AGREEMENT IN CAMS AND POSSIBLY SOME MORNING CONVECTION TO
THROW ANOTHER WRENCH INTO THINGS. HOWEVER, OVERALL, THE THREAT
SEEMS A BIT LOWER WITH INSTABILITY, AND ESPECIALLY BULK SHEAR
NOT AS HIGH AS TODAY. HOWEVER, WE WILL NEED TO MONITOR.
CONVECTION DOES LOOK TO TAPER TO ISOLATED TO SCATTERED IN
NATURE AS WE GO THROUGH THE HOLIDAY WEEKEND. TEMPERATURES WILL
BE ON THE RISE THOUGH, ESPECIALLY ON SUNDAY WITH HIGH
TEMPERATURES INTO THE 90S ACROSS THE AREA, AND PERHAPS GETTING
INTO THE UPPER 90S SOUTHWEST. BEYOND THE WEEKEND, WE SEE A
QUASI-ZONAL FLOW ALONG THE NORTHERN TIER STATES WITH OCCASIONAL
IMPULSES BRINGING CHANCES FOR SHOWERS AND THUNDERSTORMS.
TEMPERATURES REMAIN NEAR OR A LITTLE ABOVE CLIMATOLOGICAL
NORMALS (LOWER 80S) FOR THIS TIME OF YEAR.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 116 AM CDT FRI JUL 3 2026
SCATTERED THUNDERSTORMS CONTINUE OVER WESTERN AND PARTS OF
CENTRAL NORTH DAKOTA, WHICH MAY SPREAD EAST OVERNIGHT. SOME
STORMS MAY BE SEVERE OVER NORTHWEST NORTH DAKOTA VERY EARLY THIS
MORNING, WITH LARGE HAIL AND +50 KT WIND GUSTS. ANY STORM WILL
BE CAPABLE OF HEAVY DOWNPOURS BRIEFLY REDUCING VISIBILITY TO AT
LEAST IFR LEVELS. ADDITIONAL THUNDERSTORM DEVELOPMENT POSSIBLE
FRIDAY AND FRIDAY EVENING. MOSTLY VFR CONDITIONS ARE EXPECTED
TO PREVAIL OUTSIDE OF THUNDERSTORMS, ALTHOUGH THERE IS A LOW TO
MEDIUM CHANCE FOR MVFR CEILINGS DEVELOPING IN NORTH CENTRAL
NORTH DAKOTA THIS MORNING. WINDS WILL PRIMARILY BE LIGHT.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
MESOSCALE...CJS
DISCUSSION...TWH
AVIATION...JJS
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