041
FXUS63 KBIS 131656
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1156 AM CDT MON APR 13 2026
KEY MESSAGES
- MEDIUM TO HIGH CHANCES FOR SHOWERS TODAY THROUGH TONIGHT.
- A FEW THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON INTO TONIGHT,
WITH AN ISOLATED STRONG TO MARGINALLY SEVERE STORM POSSIBLE
FAR SOUTHWEST AND SOUTH CENTRAL.
- MAINLY DRY AND WARMER TUESDAY AND WEDNESDAY.
- WIDE RANGE IN TEMPERATURES FROM NORTHWEST TO SOUTHEAST
THURSDAY AS A COLD FRONT PUSHES INTO THE STATE.
- SIGNIFICANT COOL DOWN FOR THE END OF THIS WEEK, WITH MEDIUM
CHANCES FOR BOTH RAIN AND SNOW.
UPDATE
ISSUED AT 1129 AM CDT MON APR 13 2026
MIDDAY UPDATE MAINLY FOR POPS. AN EAST TO WEST AREA OF SHOWERS
WITH A FEW LIGHTNING STRIKES LIFTING NORTH ALONG THE I-94
CORRIDOR, WITH ANOTHER AREA OF SHOWERS IN THE FAR NORTH. SHORT
TERM MODELS ARE HAVING A HARD TIME PICKING UP ON THIS SO MAINLY
A HAND DRAWN AREA OF POPS THROUGH THE EARLY AFTERNOON. CAMS ARE
A LITTLE MORE CONSISTENT LATER THIS AFTERNOON THROUGH TONIGHT
WITH THE MAIN WAVE LIFTING THROUGH BRINGING ANOTHER ROUND OF
SHOWERS AND MAYBE A FEW THUNDERSTORMS. AN ISOLATED STRONG TO
POSSIBLY SEVERE STORM CAN NOT BE COMPLETELY RULED OUT LATE THIS
AFTERNOON THROUGH THIS EVENING IN THE FAR SOUTH, PROBABILITIES
LOOK TO BE QUITE LOW. SPC HAS LIMITED THE MARGINAL SEVERE THREAT
TO ONLY THE FAR SOUTHERN TIER COUNTIES WITH THEIR UPDATE LATE
THIS MORNING.
UPDATE
ISSUED AT 857 AM CDT MON APR 13 2026
FOR THE MORNING UPDATE WE LOWERED HIGH TEMPERATURES, MAINLY
ALONG AND SOUTH OF I-94. WIDESPREAD STRATUS LOOKS LIKE IT WILL
REMAIN THROUGH THE DAY (ALSO BUMPED UP SKY COVER) ACROSS MOST IF
NOT ALL OF WESTERN AND CENTRAL ND. WE ALSO ADJUSTED POPS JUST A
LITTLE. WILL CONTINUE WITH MAINLY CHANCE POPS THIS MORNING
LIFTING NORTH AND EAST. THERE HAVE BEEN SOME LIGHT RAIN SHOWERS
WITH THE REFLECTIVITIES LIFTING NORTH ALONG THE I-94 CORRIDOR.
THERE IS SOME GENERAL UPPER LEVEL RIDGING, ESPECIALLY THIS
MORNING AND THE 12Z BISMARCK SOUNDING SHOWED QUITE A BIT OF DRY
AIR REMAINING, SO QPF WITH ANY SHOWER ACTIVITY THIS MORNING IS
EXPECTED TO BE MINIMAL. THEN THE SOUTH DRIES OUT A BIT THIS
AFTERNOON, WITH HIGHER POPS LINGERING IN THE NORTH. BETTER
CHANCES WITH THE MAIN WAVE LIFTING THROUGH THE AREA LATER TODAY
AND TONIGHT. WE ALSO EXTENDED THE MENTION OF FOG THROUGH THE
MORNING. UPDATED TEXT PRODUCTS WILL BE TRANSMITTED SHORTLY.
UPDATE ISSUED AT 652 AM CDT MON APR 13 2026
A LINE OF SHOWERS CONTINUES TO MOVE FROM SOUTHWEST TO NORTHEAST
THROUGH ACROSS NORTH DAKOTA AT THE TIME OF THIS MID MORNING
UPDATE. THESE SHOWERS HAVE BEEN A LITTLE LESS PERVASIVE THEN
SUGGESTED BY THE CAMS, WITH THE 12Z SOUNDING HERE AT THE OFFICE
SUGGESTING A LAYER OF RELATIVELY DRIER AIR HELPING TO LIMIT HOW
MUCH PRECIPITATION IS REACHING THE GROUND. SHORT TERM
DETERMINISTIC MODELS CONTINUE TO ADVOCATE THESE LAYER
SATURATING THROUGH THE MID MORNING, ESPECIALLY AS SECONDARY WAVE
ALREADY PROMOTING THE DEVELOPMENT OF SHOWERS IN MONTANA MOVES
INTO THE WEST. FOR THE SHOWERS THAT WE DO HAVE THIS MORNING,
AREAS OF FOG HAVE BEEN OBSERVED TO DEVELOP AS THEY MOVE OFF TO
THE NORTHEAST, WITH VISIBILITIES ACROSS PORTIONS OF THE FAR
SOUTHWEST DROPPING AS LOW AS 1/4 SM AT TIMES. JUMPING AROUND ND
DOT CAMERAS ACROSS THIS ARE SUGGEST THIS DENSER FOG IS SOMEWHAT
LIMITED IN AREAL EXTENT, AND THE EXPECTATION IS THAT
VISIBILITIES SHOULD IMPROVE THROUGH THE MID MORNING AS SURFACE
WINDS BEGIN TO PICK UP. CONSIDERING THE MORNING COMMUTE, WE HAVE
OPTED TO ISSUE A SPS ACROSS MUCH OF THE SOUTHWEST DUE TO THE
POTENTIAL FOR RAPIDLY CHANGING VISIBILITY.
DISCUSSION
ISSUED AT 400 AM CDT MON APR 13 2026
SOUTHWESTERLY FLOW IS FOUND ACROSS THE NORTHERN PLAINS THIS
MORNING AS A PACIFIC TROUGH OVER THE WESTERN CONUS IS PROGGED TO
SPLIT AND BE ABSORBED INTO THE NORTHERN STREAM THROUGH THE DAY
TODAY. WITH THIS MOVING ACROSS THE REGION AS A SHORTWAVE
PERTURBATION, MEDIUM TO HIGH CHANCES (40 TO 70 PERCENT) FOR
PRECPITATION ARE EXPECTED ACROSS MUCH OF THE FORECAST AREA THIS
MORNING THROUGH LATE TONIGHT. WHILE MAINLY FALLING AS RAIN,
COOLING TEMPERATURES TONIGHT INTO TUESDAY COULD ALLOW FOR A
LITTLE SNOW TO MIX IN WITH THE RAIN ACROSS PORTIONS OF NORTH
CENTRAL NORTH DAKOTA, THOUGH NO SNOW ACCUMULATION IS EXPECTED.
WITH HOW PERVASIVE THIS PRECPITATION WILL BE THROUGH THIS
PERIOD, MUCH OF THE FORECAST AREA HAS MEDIUM CHANCES (40 TO 60
PERCENT) TO EXCEED 0.25" OF QPF THROUGH TUESDAY MORNING, WITH A
LOW CHANCE (10 TO 30 PERCENT) TO EXCEED 0.50". IT'S STARTING TO
GET TO THE POINT OF THE YEAR WHERE WE MUST CONSIDER THE
CONVECTIVE ENVIRONMENT AS WELL. WITH SEASONABLE WARM WEATHER
LINGERING ACROSS THE SOUTH TODAY, WITH HIGHS FROM THE MID 40S
NORTH UP TO THE UPPER 50S AND LOWER 60S SOUTH, SHORT TERM
DETERMINISTIC GUIDANCE CONTINUES TO ADVERTISE MODEST INSTABILITY
BECOMING AVAILABLE BY THE MID TO LATE AFTERNOON ACROSS PORTIONS
OF THE SOUTHWEST AND SOUTH CENTRAL, WITH MODEL MUCAPE VALUES
APPROACHING 500 J/KG. THAT BEING SAID, AN INTERROGATION OF
BUFKIT MODEL SOUNDINGS DURING THIS PERIODS REVEALS A FAIRLY
ROBUST CAP ACROSS MUCH OF THE SOUTH THROUGH THE AFTERNOON, SO WE
MAY STRUGGLE TO SEE MUCH MORE THAN ELEVATED THUNDER DURING THIS
PERIOD. THAT BEING SAID, THERE IS A LOW PROBABILITY SCENARIO
WHERE THE EARLY EROSION OF THIS CAP COULD ALLOW FOR A STRONGER
STORM TO DEVELOP, CONSIDERING THE AMPLE OF AMOUNT OF BULK SHEAR
ADVERTISED BY THE CAMS AROUND THIS TIME (APPROX 35 TO 40 KNOTS).
IF THIS SCENARIO DOES PAN OUT, SMALL HAIL AND AN ISOLATED,
MARGINALLY SEVERE WIND GUSTS UP TO 60 MPH WOULD BE POSSIBLE. SPC
AS PLACED SOUTHWESTERN AND SOUTH CENTRAL NORTH DAKOTA INTO A
LEVEL 1 OF 5 RISK FOR ISOLATED SEVERE THUNDERSTORMS FOR THIS
AFTERNOON INTO THIS EVENING.
MAINLY DRY CONDITIONS ARE THEN EXPECTED TUESDAY AND WEDNESDAY
AS NEAR ZONAL TO SLIGHTLY SOUTHWESTERLY FLOW IS ESTABLISHED
ABOVE THE FORECAST AREA. A TRANSIENT SHORTWAVE IS PROGGED TO
PASS THROUGH THE REGION TUESDAY AFTERNOON THROUGH WEDNESDAY,
PROMOTING ANOTHER ROUND OF LIGHT RAINFALL, THOUGH THERE IS
FAIRLY STRONG AGREEMENT BETWEEN ENSEMBLE MEMBERS ON THIS
REMAINING TO THE SOUTH OF NORTH DAKOTA AT THIS TIME. WITH THE
NEAR ZONAL FLOW PERSISTING THROUGH THE MID WEEK, WARMING HIGHS
FROM THE 50S AND 60S ON TUESDAY TO THE 60S AND 70S ON WEDNESDAY
ARE EXPECTED.
A TRANSITION BACK TO SOUTHWESTERLY FLOW IS THEN ANTICIPATED
LATE WEDNESDAY INTO THURSDAY AS A STRONG UPPER LEVEL LOW MAKES
LANDFALL IN THE PACIFIC NORTHWEST. CHANCES FOR PRECPITATION (40
TO 60 PERCENT) INCREASE THROUGH THE DAY THURSDAY AS A SURFACE
LOW COMPLEX MOVES OUT OF THE SOUTHERN CANADIAN PRAIRIES AND
APPROACHES WESTERN AND CENTRAL NORTH DAKOTA. WHILE INITIALLY
FALLING AS RAIN THROUGH THE DAY THURSDAY, WITH LINGERING HIGHS
BROADLY IN THE LOWER 50S NORTHWEST TO MID 70S SOUTHEAST, A SHARP
TRANSITION TO ALL SNOW IS EXPECTED TO OCCUR THURSDAY NIGHT INTO
FRIDAY AS A COLD FRONT ASSOCIATED WITH THIS DROPS ACROSS THE
AREA. WITH THIS, AT LEAST LIGHT ACCUMULATIONS OF SNOW CAN BE
EXPECTED ACROSS MUCH OF THE FORECAST AREA, WITH THE NBM
ADVERTISING A LIGHT DUSTING ACROSS THE SOUTH UP TO AN INCH OR
TWO ALONG THE INTERNATIONAL BORDER. CLUSTER ANALYSIS REVEALS
THIS TO THE MAJORITY SOLUTION, WITH AROUND 55 PERCENT OF MEMBERS
FAVORING A NORTHERLY TRACK TO THE LOW COMPLEX. A MINORITY
CLUSTER ALSO EXISTS (45 PERCENT OF ENSEMBLE MEMBERS), WHICH HAS
A SLIGHTLY STRONGER LOW COMPLEX DIPPING FURTHER TO THE SOUTH
THAN WHAT IS ADVERTISED BY THE NBM, ALLOWING FOR A QUICKER
TRANSITION TO ALL SNOW ACROSS THE SOUTH OVERNIGHT INTO FRIDAY.
WITH THIS SCENARIO, ACCUMULATIONS UP TO AN INCH WOULD BE
POSSIBLE AS FAR SOUTH AS INTERSTATE 94. IN EITHER SCENARIO,
BREEZY TO WINDY CONDITIONS CAN BE EXPECTED THURSDAY AND FRIDAY
AS AND PRESSURE GRADIENT SHARPENS, AND CAA INCREASES ALONG AND
BEHIND THE COLD FRONT. THAT BEING SAID, THE UPPER END OF THESE
WINDS MAY BE ONLY NEAR TO MARGINALLY WIND ADVISORY CRITERIA DUE
TO THE TIMING OF THE FRONTAL PASSAGE AND THE LACK OF A STRONG
850-700MB JET DURING THIS PERIOD. THIS THINKING SEEMS TO FALL IN
LINE WITH THE LACK OF ANY ANOMALOUS WIND SIGNAL IN THE MOST
RECENT ECMWF EFI, THOUGH WE WILL NEED TO CONTINUE MONITORING
THIS PERIOD MOVING FORWARD. AFTER THE MUCH COOLER WEATHER ON
FRIDAY, THERE IS DECENT AGREEMENT IN THE ENSEMBLE ON WARMING
TEMPERATURES BY THE END OF THE WEEKEND INTO EARLY NEXT WEEK AS
LONGWAVE RIDGING BUILDS IN BEHIND THE TROUGH, THOUGH THERE IS
SOME MODEST DISAGREEMENT ON THE TIMING OF THIS TRANSITION BACK
TOWARD WARMER WEATHER.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1129 AM CDT MON APR 13 2026
EXPECT WIDESPREAD IFR TO LIFR CEILINGS ACROSS WESTERN AND
CENTRAL ND THROUGH TONIGHT. THERE WILL BE TIMES THIS AFTERNOON
AND EVENING WHEN SOME MVFR CEILINGS MAY BE FOUND, BUT OVERALL,
EXPECT LOW STRATUS TO REMAIN THROUGH MUCH OF THE NIGHT. DO
EXPECT SOME IMPROVEMENT IN CEILING FROM WEST TO EAST TUESDAY
MORNING. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE CENTRAL AND SOUTH, THEN MOSTLY IN THE SOUTH TONIGHT.
ANY THUNDERSTORMS WILL HAVE THE CAPABILITY OF PRODUCING GUSTY
AND ERRATIC WINDS WITH LOW VSBYS IN HEAVY DOWNPOURS. EXPECT AN
EASTERLY SURFACE FLOW TODAY AND TONIGHT 5 TO 15 KTS, TURNING
SOUTH TO SOUTHWEST 5 TO 15 KTS ON TUESDAY.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...TWH
DISCUSSION...ADAM
AVIATION...TWH
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page