781
FXUS63 KBIS 181737
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1237 PM CDT THU SEP 18 2025
KEY MESSAGES
- SHOWERS, ALONG WITH A FEW RUMBLES OF THUNDER, REMAIN IN THE
FORECAST THROUGH FRIDAY. THE HIGHEST RAIN CHANCES ARE TODAY
OVER SOUTH CENTRAL AND SOUTHEASTERN PARTS OF THE STATE. THE
HIGHEST CHANCES TONIGHT AND FRIDAY WILL BE ALONG AND EAST OF
THE HIGHWAY 83 CORRIDOR.
- SEVERE WEATHER IS NOT EXPECTED, THOUGH PERIODS OF HEAVY RAIN
MAY BRING SOME LOCALIZED MINOR FLOODING AT TIMES.
- HIGH TEMPERATURES WILL BE MAINLY IN THE 50S AND 60S TODAY AND
FRIDAY, THEN WARMING INTO THE 70S AND LOW 80S BY SUNDAY. LOW
TEMPERATURES WILL BE IN THE 40S TO MID 50S.
UPDATE
ISSUED AT 1235 PM CDT THU SEP 18 2025
THE LOW PRESSURE IN NORTHEAST SOUTH DAKOTA HAS MOVED SLIGHTLY
NORTH. WITH THIS, THE RAIN BANDS HAVE PROGRESSED WEST AND NORTH.
THIS TREND WILL CONTINUE FOR THE NEXT 20 HOURS BEFORE THE LOW
FINALLY MOVES EAST. THE LATEST NBM WAS ADDED TO THE FORECAST.
UPDATE
ISSUED AT 926 AM CDT THU SEP 18 2025
RAIN SHOWERS CONTINUE THEIR WESTWARD TREND THIS MORNING. MORE
SHOWERS HAVE FORMED IN WESTERN NORTH DAKOTA AS WELL. THE POP
FORECAST WAS UPDATED TO REFLECTED THE RADAR, INCLUDING SLOWING
DOWN THE WESTWARD EXPANSION THIS MORNING IN THE SOUTH CENTRAL.
FOG IN THE NORTHWEST CONTINUES.
UPDATE
ISSUED AT 642 AM CDT THU SEP 18 2025
PATCHY FOG HAS DEVELOPED IN WESTERN AND NORTH CENTRAL ND. FOR
THE MOST PART, VISIBILITY REMAINS IN EXCESS OF FOUR MILES.
HOWEVER, THERE ARE A FEW OBSERVATIONS THAT ARE LOWER, INCLUDING
THE WILLISTON AIRPORT. THAT SAID, LIMITED WEBCAMS IN THE CITY
ITSELF ARE FAR LESS FOGGY. OTHERWISE, RAIN SHOWERS CONTINUE
SLOWLY PUSHING INTO THE STATE. ALL IN ALL, THE FORECAST REMAINS
ON TRACK.
DISCUSSION
ISSUED AT 327 AM CDT THU SEP 18 2025
QUASI-STATIONARY LOW PRESSURE SYSTEM IS CURRENTLY, AND WILL
REMAIN, CENTERED OVER SOUTH DAKOTA TODAY, BEFORE VERY SLOWLY
MEANDERING NORTHWARD TONIGHT AND THROUGH THE DAY FRIDAY. AS A
RESULT, EXPECT WIDESPREAD RAIN SHOWERS TO CONTINUE TODAY THROUGH
TONIGHT, ESPECIALLY FOR SOUTH CENTRAL AND EASTERN NORTH DAKOTA.
SHOWERS WILL THEN PUSH NORTHWARD BEFORE GRADUALLY ENDING FROM
WEST TO EAST ON FRIDAY, THOUGH MAY LINGER IN THE TURTLE
MOUNTAINS AND EASTERN ND INTO SATURDAY. A FEW RUMBLES OF
THUNDER ARE POSSIBLE TODAY, MAINLY IN FAR SOUTH CENTRAL AND
SOUTHEASTERN PORTIONS OF THE STATE. THOUGH A FEW RUMBLES ARE
ALSO POSSIBLE IN WESTERN ND. SEVERE WEATHER IS NOT EXPECTED,
THOUGH LOCALIZED MINOR FLOODING IS POSSIBLE IF MODERATE TO HEAVY
RAIN (THUNDERSTORMS) REMAINS OVER ONE PLACE FOR AN EXTENDED
PERIOD.
ONCE THIS SYSTEM CLEARS OUT, MOSTLY DRY CONDITIONS ARE EXPECTED
THROUGH THE MIDDLE OF NEXT WEEK. THE ONE EXCEPTION IS LATE THIS
WEEKEND AND INTO MONDAY WHEN A PASSING SHORTWAVE MAY PRODUCE A
FEW SHOWERS. FORTUNATELY, THE NBM HAS FINALLY LATCHED ONTO THIS
IDEA AND PUT MENTIONABLE POPS INTO THE FORECAST.
DUE TO WIDESPREAD RAIN SHOWERS AND CLOUD COVER, HIGHS TODAY WILL
BE MOSTLY IN THE UPPER 50S TO LOW 60S, AND MOSTLY IN THE 60S ON
FRIDAY. A WARMING TREND IS THEN EXPECTED THIS WEEKEND AS A
THERMAL RIDGE PASSES THROUGH, BRINGING HIGHS INTO THE MID 70S
TO LOW 80S BY SUNDAY. THE AFOREMENTIONED SHORTWAVE MONDAY FAVORS
COOLER HIGHS BACK INTO THE MID 60S TO LOW 70S. BEYOND MONDAY,
UNCERTAINTY REMAINS IN WHETHER RIDGING WILL PREVAIL, OR IF FLOW
ALOFT WILL BE MORE ZONAL OR NORTHWESTERLY. THE NBM FAVORS A
SEASONABLE TEMPERATURE OUTCOME WITH HIGHS MOSTLY IN THE UPPER
60S TO LOW 70S. LOWS THROUGH THE NEXT WEEK ARE ALSO FAVORED TO
BE SEASONABLE TO SEASONABLY WARM AND IN THE 40S (SEASONABLE) TO
LOW 50S (SEASONABLY WARM).
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
ISSUED AT 1230 PM CDT THU SEP 18 2025
LIFR CIGS ARE PRESENT IN THE SOUTH AND EAST, ESPECIALLY IN THE
RAIN BANDS. MVFR TO VFR ELSEWHERE. BANDS OF RAIN WILL MOVE EAST
TO WEST ACROSS MOST OF THE STATE THROUGH FRIDAY MORNING. A FEW
THUNDERSTORMS ARE POSSIBLE IN THE EAST THIS EVENING. WINDS WILL
STAY AROUND 12KTS, EXCEPT IN THE SOUTHEAST WHERE GUSTS AROUND
25 ARE POSSIBLE FROM THE EAST. CIG RAISE TOWARDS THE END OF THE
PERIOD.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...SMITH
DISCUSSION...TELKEN
AVIATION...SMITH
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