709
FXUS63 KBIS 190208
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
908 PM CDT SAT JUL 18 2026
KEY MESSAGES
- HOT CONDITIONS RETURN ON SUNDAY WITH HIGH TEMPERATURES AND
HEAT INDEX VALUES AROUND 95 TO 100.
- ISOLATED TO SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE
SUNDAY AFTERNOON AND EVENING. EXPECTED HAZARDS INCLUDE HAIL AS
LARGE AS 2 INCHES IN DIAMETER AND DAMAGING WINDS UP TO 70
MPH, WITH A TORNADO POSSIBLE.
- WINDY NORTHWEST WINDS EXPECTED MONDAY. WINDS COMBINED WITH LOW
HUMIDITY VALUES COULD BRING CRITICAL FIRE WEATHER CONDITIONS
ACROSS PARTS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA.
- BRIEF COOLDOWN EXPECTED TUESDAY, FOLLOWED BY A WARMING TREND
INTO NEXT WEEKEND.
UPDATE
ISSUED AT 908 PM CDT SAT JUL 18 2026
RADAR ECHOES OVER CENTRAL NORTH DAKOTA ARE BECOMING MORE
ISOLATED AT THIS TIME. THESE REMAIN MOSTLY VIRGA, THOUGH A FEW
SPRINKLES COULD BE REACHING THE GROUND. OTHERWISE,
REDUCED/SLOWED POPS IN FAR SOUTHWESTERN ND THIS EVENING BASED ON
THE LATEST MODEL AND RADAR TRENDS. STILL COULD SEE A FEW
SHOWERS DEVELOP OVERNIGHT TONIGHT MAINLY IN THE SOUTHWEST AND
SOUTH CENTRAL. WHILE A FEW RUMBLES OF THUNDER AREN'T ENTIRELY
OUT OF THE QUESTION, INSTABILITY TONIGHT LOOKS PRETTY LIMITED
OVERALL.
UPDATE
ISSUED AT 643 PM CDT SAT JUL 18 2026
SCATTERED RADAR ECHOES ARE PRESENT ACROSS MUCH OF THE FORECAST
AREA. HOWEVER, VERY DRY AIR THROUGH THE LOWER LEVELS, INCLUDING
DEWPOINT DEPRESSIONS GENERALLY IN EXCESS OF 20 DEGREES AND OFTEN
OVER 30 DEGREES, IS LIMITING MOISTURE OUTPUT. NEVERTHELESS, A
FEW SPRINKLES HAVE RECENTLY BEEN OBSERVED AT THE OFFICE.
SPRINKLES AND PERHAPS A FEW BRIEF SHOWERS REMAIN POSSIBLE OVER
THE NEXT HOUR OR TWO MAINLY IN NORTHWESTERN AND CENTRAL NORTH
DAKOTA.
DISCUSSION
ISSUED AT 234 PM CDT SAT JUL 18 2026
ELEVATED WARM FRONT AND WEAK SHORTWAVE WILL BRING SOME HIGH
BASED SHOWERS THROUGH TONIGHT FROM WEST TO EAST. WITH LIMITED
INSTABILITY EXPECTED, THE THREAT FOR THUNDERSTORMS IS LOW AS IS
THE THREAT FOR SEVERE WEATHER FOR TONIGHT. WARM TEMPERATURES
BEHIND THIS FRONT COMBINED WITH SOME INCREASED CLOUD COVER WILL
BRING WARMER LOWS IN THE 60S TONIGHT. THIS CLOUD COVER SHOULD
ALSO LIMIT THE FOG POTENTIAL FOR TONIGHT, ALTHOUGH ANY AREAS
THAT CLEAR AND HIGH LIGHT WINDS COULD SEE AT LEAST PATCHY FOG
RETURN. CONFIDENCE IN FOG IS NOT HIGH ENOUGH TO INCLUDE IN THE
FORECAST AT THIS TIME.
SUNDAY, HOT TEMPERATURES WITH ISOLATED TO SCATTERED SEVERE
THUNDERSTORMS REMAIN FORECAST. STARTING WITH THE HEAT, WESTERLY
FLOW ALOFT WITH A SURFACE WARM FRONT AND SOUTHERLY FLOW WILL
WARM TEMPERATURES BACK INTO THE 90S TO NEAR 100 DEGREES FOR
SUNDAY. SOUTHERLY FLOW WILL MAINTAIN DEWPOINTS IN THE 60S
PROVIDING FOR HEAT INDEX VALUES NEAR TO OVER 100 DEGREES IN SOME
AREAS. HEAT RISK IS MODERATE TO MAJOR FOR MOST OF THE CWA, WHILE
SOME EXTREME RISK IS SHOWING UP IN CENTRAL PORTIONS FOR WET
BULB GLOBAL TEMPERATURES. TODAY'S FORECAST CAME IN SLIGHTLY
COOLER THAN PREVIOUS FOR SUNDAY, PERHAPS LIMITING HOW WIDESPREAD THE
MORE DANGEROUS HEAT WILL REACH. THUS ISSUED A HEAT ADVISORY FOR
THE HIGHER CONFIDENCE AREAS IN SOUTHWESTERN AND SOUTH CENTRAL
PORTIONS. DEPENDING ON CLOUD COVER, DAYTIME HEATING, AND OVERALL
TIMING OF THE MENTIONED FRONTS THIS MAY NEED TO BE EXPANDED INTO
NORTH CENTRAL AND EASTERN PORTIONS AND WILL HAVE TO BE
REEVALUATED AT LATER FORECAST TIMES.
SPC HAS MAINTAIN AND EXPANDED SOMEWHAT THE SLIGHT RISK (LEVEL 2
OF 5) FOR SEVERE WEATHER ON SUNDAY. CAMS ALSO REMAIN ROBUST
SUNDAY AFTERNOON THROUGH SUNDAY EVENING. THE SETUP REMAINS
SIMILAR WITH A WARM FRONT BEING REPLACES BY A COLD FRONT SUNDAY
AFTERNOON THROUGH SUNDAY EVENING AND NIGHT. MODEST CAPPING WILL
GIVE WAY TO FORECAST CAPE APPROACH 3000 J/KG, WITH 0-6 KM SHEAR
AROUND 40 TO 50 KTS AS THE MENTIONED FRONT PROGRESSES THROUGH.
THUS KEPT HAZARDS THE SAME WITH VERY LARGE HAIL UP TO 2 INCHES
IN DIAMETER AND DAMAGING WINDS UP TO 70 MPH. THERE ALSO REMAINS
A CONDITIONAL RISK FOR A TORNADO WITH A VERY SIMILAR SETUP TO
WHAT WAS OBSERVED LAST THURSDAY. FORECAST CAPE AND SHEAR WOULD
BOTH BE SUFFICIENT FOR TORNADOGENESIS WITH ANY SUPERCELL THAT
REMAINS ANCHORED TO THE VORTICITY-RICH AND BAROCLINICALLY-WEAK
SURFACE BOUNDARY. THE BIGGEST UNCERTAINTY REMAINS WITH STORM
MODE. THIS WILL DEPEND ON HOW THE FRONTS ORIENTATE THEMSELVES TO
A GENERALLY WESTWARD SHEAR VECTOR, ALTHOUGH INITIALLY THERE
DOES LOOK TO BE A MULTI- CLUSTER TO DISCRETE SUPERCELL MODE
POTENTIAL. THESE STORMS COULD THEN REMAIN MULTICLUSTER OR GO
LINEAR QUICKLY. WITH INVERTED V SOUNDING, HIGH CAPE, AND HIGH
SHEAR, THIS COULD BRING AN INCREASED WIND THREAT. WITH THE
UNCERTAINTY OF STORM MODE, ALL SHOULD BE WEATHER AWARE FOR
SUNDAY AFTERNOON AND EVENING. STORMS OVERALL LOOK TO PUSH OUT OF
THE AREA SUNDAY NIGHT. WINDS BECOME WESTERLY AND TEMPERATURES
LOOK TO REMAIN IN THE 60S.
ON MONDAY, THE SHORTWAVE OUT OF SASKATCHEWAN IS EXPECTED TO SWIFTLY
MOVE SOUTHEAST THROUGH MANITOBA INTO THE WESTERN GREAT LAKES REGION.
PRECIPITATION CHANCES ARE FORECASTED TO BE VERY LOW, WITH A LACK OF
SUFFICIENT INGREDIENTS FOR DEVELOPMENT. A TIGHT PRESSURE GRADIENT,
AMPLE COLD AIR ADVECTION, AND MIXING ANTICIPATED TO PUSH THROUGH ON
THE BACK END OF THIS FRONT WILL PROVOKE INCREASED WIND INTENSITY
ACROSS NORTH DAKOTA. FOR THE DURATION OF DAYLIGHT ON MONDAY, GUSTY
CONDITIONS CAN BE EXPECTED, PEAKING IN THE AFTERNOON. NBM FORECASTS
ESTIMATE THE HIGHEST SURFACE GUSTS TO BE IN THE 40-45 MPH RANGE IN
THE EASTERN HALF OF THE STATE; HOWEVER, THE NBM SOMETIMES TENDS
TO FAVOR HIGHER END SOLUTIONS FOR WIND, LEADING TO CONCERNS
ABOUT OVERESTIMATION BIAS. TRENDS IN WIND INTENSITY WILL BE
MONITORED AS WE MOVE INTO A CLOSER FORECAST RANGE, ESPECIALLY
IF IT TRENDS UPWARDS TOWARDS WIND ADVISORY CRITERIA.
ALSO OF NOTE ON MONDAY IS THE RISK FOR CRITICAL FIRE CONDITIONS IN
THE SOUTHWEST PORTION OF NORTH DAKOTA. WHILE HIGH TEMPERATURES ON
MONDAY ARE FORECASTED TO DIP IN THE NORTHERN HALF OF THE STATE (FROM
THE UPPER 70S TO THE MID 80S), IN THE SOUTHERN HALF OF THE STATE,
HIGHS ARE EXPECTED TO REMAIN IN THE UPPER 80S AND LOWER 90S DUE TO
THE FORECASTED TIMING OF THE COLD FRONT. ADDITIONALLY, IN THE
SOUTHWEST, MINIMUM RH VALUES ARE ANTICIPATED TO BE LOW (20-30%) WITH
DEWPOINTS IN THE MID TO UPPER 40S. WITH NORTHWEST SURFACE WINDS
SUSTAINED UP TO 25 MPH FOR A GOOD PORTION OF THE AFTERNOON AND FUELS
DRYING DUE TO PERSISTENT LACK OF PRECIPITATION IN THE AREA, CRITICAL
FIRE WEATHER CONDITIONS ARE POSSIBLE. IT IS ALSO IMPORTANT TO NOTE
THAT THERE IS UNCERTAINTY ON WHETHER FIRE WEATHER CONDITIONS WILL
COME TO FRUITION GIVEN POSSIBLE CHANGES TO THE TIMING OF THE FRONT'S
PASSAGE. CURRENTLY, THE INGREDIENTS FOR FIRE WEATHER ON MONDAY LINE
UP TO OCCUR AT THE SAME TIME, PROVIDING SUFFICIENT CONCERN THAT
THESE CONDITIONS COULD OCCUR. WE WILL CONTINUE TO KEEP AN EYE OUT
FOR ANY CHANGES OR DISPLACEMENTS OF THESE INGREDIENTS.
MOVING THROUGH THE WORK WEEK, TUESDAY IS EXPECTED TO REMAIN THE
COOLEST DAY OF THE FORECAST PERIOD. NBM HIGH TEMPERATURES REMAIN IN
THE MID 70S TO THE MID 80S FROM NORTH TO SOUTH, RESPECTIVELY.
ADDITIONALLY, WINDS WILL DECREASE FROM MONDAY, PROVIDING CALMER
CONDITIONS. MULTIPLE ENSEMBLES SHOW A PROMPT PROGRESSION OF THE
SHORTWAVE MOVING EAST ACROSS THE GREAT LAKES, WITH A RIDGE
FOLLOWING IN THE LATE WEEK. THUS, THE HEAT RELIEF WILL LIKELY
BE BRIEF, WITH HIGHS EXPECTED TO TREND UP FOLLOWING TUESDAY.
CURRENTLY, NBM MAXIMUM TEMPERATURES LOOK TO INCREASE STEADILY
THROUGHOUT THE WEEK UP TO THE HIGH 90S BY SATURDAY IN THE
SOUTHWEST PORTION OF NORTH DAKOTA, WITH BOTH MAXIMUM WET-BULB
GLOBAL TEMPERATURE AND HEAT RISK SHOWING UPWARDS TRENDS AS
WELL. EVEN SO, THERE IS STILL DISAGREEMENT AMONG ENSEMBLES ON
HOW HOT THESE TEMPERATURES WILL END UP BEING. THIS IS LIKELY DUE
TO UNCERTAINTY SURROUNDING THE RIDGE STRENGTH AND WHEN AND
WHERE IT MAY FLATTEN AS WE MOVE INTO THE WEEKEND. FINALLY,
PRECIPITATION CHANCES ARE LOOKING FAIRLY LOW THROUGH NEXT WEEK.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 643 PM CDT SAT JUL 18 2026
SCATTERED RADAR ECHOES ARE PRESENT ACROSS MUCH OF NORTHWESTERN
AND CENTRAL NORTH DAKOTA. HOWEVER, VERY DRY AIR IS RESULTING
MOSTLY IN VIRGA, ALTHOUGH BRIEF SPRINKLES WERE OBSERVED AT
KBIS. THESE SCATTERED RETURNS SHOULD DISSIPATE OVER THE NEXT
HOUR OR TWO BEFORE ANOTHER CHANCE OF SHOWERS, PERHAPS WITH A FEW
RUMBLES OF THUNDER, IS POSSIBLE OVERNIGHT. THE TERMINALS MOST
LIKELY TO BE IMPACTED OVERNIGHT ARE KBIS AND KDIK, AS INDICATED
BY PROB30S.
CONFIDENCE IS INCREASING THAT SCATTERED SHOWERS AND
THUNDERSTORMS WILL DEVELOP IN WESTERN AND CENTRAL NORTH DAKOTA
SUNDAY AFTERNOON. HOWEVER, THE PLACEMENT AND COVERAGE REMAINS IN
QUESTION. THE HIGHEST CONFIDENCE WITHIN THE TAF PERIOD IS AT
KMOT, ALTHOUGH SIMILAR CONFIDENCE IS PRESENT FOR KBIS SUNDAY
EVENING MOSTLY JUST BEYOND THE TAF PERIOD. THUNDERSTORMS SUNDAY
AFTERNOON AND EVENING COULD BE SEVERE WITH GUSTY AND ERRATIC
WINDS, ALONG WITH LARGE HAIL, AS THE PRIMARY THREATS.
BIS WATCHES/WARNINGS/ADVISORIES
HEAT ADVISORY FROM 1 PM CDT /NOON MDT/ TO 9 PM CDT /8 PM MDT/
SUNDAY FOR NDZ017>020-031>033-035-040>044-046>048-050-051-
059>062.
UPDATE...TELKEN
DISCUSSION...ANGLIN
AVIATION...TELKEN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page