455
FXUS63 KBIS 292014
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
314 PM CDT TUE JUL 29 2025
KEY MESSAGES
- ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PARTS OF
WESTERN NORTH DAKOTA THIS AFTERNOON AND EVENING. EXPECTED
HAZARDS INCLUDE HAIL AS LARGE AS HALF DOLLARS AND WIND GUSTS
UP TO 60 MPH.
- BELOW AVERAGE TEMPERATURES, ALONG WITH PERIODIC ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS, ARE EXPECTED THE REST OF
THE WORK WEEK WITH HIGHS MOSTLY IN THE 70S AND LOWS MOSTLY IN
THE 50S.
DISCUSSION
ISSUED AT 314 PM CDT TUE JUL 29 2025
THIS AFTERNOON, THE SYNOPTIC PATTERN WAS CHARACTERIZED BY A
STOUT UPPER HIGH OVER THE SOUTHERN PLAINS, WHILE RIDGING WAS
ATTEMPTING TO BUILD OVER THE WESTERN CONUS IN RESPONSE TO A DEEP
LOW OFF THE COAST OF BRITISH COLUMBIA. FLOW ACROSS NORTH DAKOTA
WAS ZONAL, WITH ANOTHER DEEP HUDSON BAY LOW TO THE NORTHEAST. AT
THE SURFACE, HIGH PRESSURE WAS CENTERED IN CENTRAL SASKATCHEWAN,
WITH A WEAK SURFACE TROUGH ANALYZED THROUGH CENTRAL AND EASTERN
MONTANA.
AS FLOW ALOFT TO OUR WEST BECOMES A BIT MORE AGITATED AND A
SHORTWAVE MOVES THROUGH THE REGION, FORCING FOR ASCENT BECOMES
BROAD BUT WEAK. A FEW ISOLATED THUNDERSTORMS ARE ALREADY ONGOING
ACROSS EASTERN MONTANA AND INTO NORTHWEST NORTH DAKOTA THIS
AFTERNOON, IN AN ENVIRONMENT WITH UP TO 1500 J/KG OF MOSTLY
UNCAPPED MLCAPE, MODESTLY STEEP LOW- AND MID-LEVEL LAPSE RATES,
AND BULK SHEAR ON THE ORDER OF 50 KNOTS. CAMS HAVE BEEN A BIT
INCONSISTENT REGARDING TIMING OF ANY STRONGER TO SEVERE STORMS,
BUT ARE MORE STEADY IN HIGHLIGHTING WESTERN NORTH DAKOTA AS THE
MOST LIKELY AREA FOR CONVECTION THIS AFTERNOON AND EVENING. WE
CONTINUE TO ADVERTISE ISOLATED SEVERE THUNDERSTORMS WITH THE
MAIN HAZARDS AS HAIL UP TO THE SIZE OF PING PONG BALLS AND WIND
GUSTS UP TO 60 MPH. LOW TO MEDIUM PRECIPITATION CHANCES CONTINUE
THIS EVENING, THROUGH THE NIGHT, AND INTO WEDNESDAY AFTERNOON,
SHRINKING TO BE FOCUSED ON THE SOUTHWEST PART OF THE STATE. SOME
NEAR SURFACE SMOKE IS POSSIBLE LATE TONIGHT THROUGH MUCH OF
WEDNESDAY, PRIMARILY ACROSS THE EAST AND SOUTH.
THE REMAINDER OF THE WORK WEEK IS RELATIVELY CONSISTENT,
FORECAST WISE, WITH NORTHWESTERLY FLOW DOMINATING AS THE UPPER
RIDGE SLOWLY DRIFTS OVER THE NORTHERN ROCKIES. HIGH TEMPERATURES
WILL REMAIN STEADILY IN THE 70S, AND LOWS IN THE 50S. CHANCES
FOR SHOWERS AND THUNDERSTORMS ARE ON AND OFF THROUGH THIS TIME,
WITH A FEW DIFFERENT SHORTWAVES MOVING THROUGH THE BROAD NORTHWEST
FLOW. CHANCES ARE HIGHEST IN THE SOUTHWEST PART OF THE STATE,
WITH THE BULK OF FAVORABLE FORCING SKIRTING BY NORTH DAKOTA.
NSSL AND CSU MACHINE LEARNING PROBABILITIES SHOW THE LIKELIHOOD
OF SEVERE WEATHER ACROSS THE ARE AS A WHOLE ARE QUITE LOW, WITH
THE ONLY AREA WITH ANY POTENTIAL THE SOUTHWEST PART OF THE
STATE.
THE UPPER RIDGE AXIS IS PROGGED TO EXTEND ACROSS THE FORECAST
AREA AND INTO THE SOUTHERN CANADIAN PRAIRIES TO START THE
WEEKEND, WITH TEMPERATURES SLOWLY WARMING BACK CLOSER TO NORMAL,
IN THE UPPER 70S TO MID 80S. WE CONTINUE THE SOMEWHAT ACTIVE
PATTERN, WITH DETERMINISTIC GUIDANCE SHOWING INSTABILITY
STARTING TO INCREASE ACROSS A LARGER PORTION OF THE STATE ON
SATURDAY AND SUNDAY. MORE OF THE SAME IS FAVORED FOR AT LEAST
THE BEGINNING OF NEXT WORK WEEK, WITH ABOVE NORMAL TEMPERATURES
FAVORED THROUGH THE FIRST WEEK OF AUGUST, AND NO INDICATIONS OF
A SIGNIFICANT DRY PATTERN COMING UP.
AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/
ISSUED AT 1245 PM CDT TUE JUL 29 2025
OVERALL VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD, ALTHOUGH
THERE ARE SOME SCT MVFR CEILINGS ACROSS MUCH OF WESTERN AND
CENTRAL NORTH DAKOTA. MAIN FORECAST FOCUS IS ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS, PRIMARILY ACROSS WESTERN
NORTH DAKOTA, THIS AFTERNOON AND INTO THE EVENING. MAIN HAZARDS
WILL BE GUSTY ERRATIC WINDS AND LARGE HAIL. DID INCLUDE TEMPO
AND PROB30 GROUPS AT TERMINALS MOST LIKELY TO SEE IMPACTS.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
DISCUSSION...JONES
AVIATION...JONES
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