319
FXUS63 KBIS 201439
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
939 AM CDT MON APR 20 2026
KEY MESSAGES
- HIGHS TODAY WARM TO ABOVE NORMAL, WITH HIGHS IN THE MID 60S
TO MID 70S.
- TEMPERATURES WILL CONTINUE TO AVERAGE WELL ABOVE NORMAL BOTH
TUESDAY AND WEDNESDAY, ALONG WITH MAINLY DRY WEATHER
CONDITIONS.
- ACTIVE WEATHER PATTERN IS FAVORED WEDNESDAY NIGHT THROUGH THE
END OF THE WEEK, WITH MEDIUM TO HIGH PRECIPITATION CHANCES
ALONG WITH A STRONG COOLING TREND.
UPDATE
ISSUED AT 939 AM CDT MON APR 20 2026
SURFACE TROUGH IS ANALYZED FROM WEST CENTRAL MANITOBA BACK TO
EASTERN MONTANA, WITH WINDS BECOMING MORE NORTHWESTERLY ON THE
WEST SIDE OF THE BOUNDARY. A FEW HIGH CLOUDS ARE DRIFTING
THROUGH BUT SHOULD BE A PLEASANT SPRING DAY, ESPECIALLY AS WINDS
LESSEN A BIT THROUGH THE DAY. NO CHANGES NEEDED WITH THIS
UPDATE.
UPDATE
ISSUED AT 612 AM CDT MON APR 20 2026
NO CHANGES OUTSIDE OF SKY COVER AND HOURLY WEATHER ELEMENTS.
FOR LATEST FORECAST DISCUSSION SEE BELOW.
DISCUSSION
ISSUED AT 430 AM CDT MON APR 20 2026
CURRENTLY, WEST-NORTHWEST FLOW ALOFT OVER THE REGION WITH AN
UPSTREAM EMBEDDED IMPULSE OVER SOUTHERN ALBERTA AND AN
ASSOCIATED AND SUBTLE SURFACE LOW/TROUGH OVER SOUTHERN
SASKATCHEWAN STRETCHING SOUTH ACROSS EASTERN MONTANA. A MOSTLY
CLEAR SKY AT THE MOMENT WITH UPPER LEVEL CLOUDS STREAMING
SOUTHEASTERLY ALOFT. WITH WAA ONGOING, TEMPERATURES THIS MORNING
MUCH MORE MODERATE COMPARED TO THE PREVIOUS FEW MORNINGS, WITH
TEMPERATURES CURRENTLY RANGING IN THE UPPER 20S TO UPPER 30S
OVER WEST/CENTRAL ND (COMPARED TO TEENS AND 20S PREVIOUSLY).
EMBEDDED IMPULSE AND SUBTLE SFC LOW PUSH ACROSS THE NORTHERN
PLAINS TODAY, DRAGGING A WEAK COLD FRONT SOUTHWARD ACROSS
WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING AND AFTERNOON.
MAIN RESULT WILL BE A WIND SHIFT FROM SOUTH TO WEST AND
EVENTUALLY TO NORTHWEST. OUTSIDE OF THE JAMES RIVER VALLEY,
WINDS REMAIN RELATIVELY LIGHT, SUSTAINED UP TO 15 MPH OR SO.
ACROSS THE JAMES, GUSTY SOUTHERLY WINDS, CURRENTLY OVER SOME
LOCATIONS NOW, CONTINUE THROUGH EARLY/MID AFTERNOON BEFORE
DECREASING. FAIRY DRY THIS AFTERNOON, WITH FORECAST HIGHS IN THE
MID 60S TO MID 70S COUPLED WITH DEWPOINT TEMPS IN THE 30S,
RESULTING IN FORECAST MIN RH VALUES IN THE 20S MOST AREAS, WITH
SOME TEENS SOUTHWEST. OPTED TO MAINTAIN A MENTION OF NEAR
CRITICAL FIRE WEATHER IN THE SOUTHEAST, AND WILL ALSO MENTION IN
THE SOUTHWEST IN CASE OUR WINDS OVERPERFORM THERE (STILL HAVE A
WIND SHIFT REGARDLESS).
FLOW ALOFT WILL GRADUALLY TRANSITION TO MORE QUASI-ZONAL INTO
TUESDAY, CONTINUING THE WARMING TREND AND MAINTAINING A DRY
WEATHER FORECAST. WARMEST DAY THIS WEEK WILL BE ON WEDNESDAY,
WHEN BROAD RIDGING AMPLIFIES OVER THE NORTHERN PLAINS AHEAD OF A
STRONG UPPER LEVEL TROUGH DEVELOPING INTO THE WESTERN CONUS.
AHEAD OF THIS TROUGH, A LEE SIDE SURFACE LOW STRENGTHENS, AND
RESULTS IN STRONG SOUTHERLY FLOW AND WAA ACROSS THE DAKOTAS.
HIGH TEMPERATURES INTO THE LOW/MID 80S ACROSS THE SOUTH ARE
FORECAST, WITH 70S ELSEWHERE. INCREASING BOUNDARY LAYER MOISTURE
UNDER THIS FLOW PATTERN AS WELL, RESULTING IN UNSEASONABLY HIGH
MUCAPE ACROSS THE EASTERN HALF OF THE STATE TO AROUND 1K J/KG
DURING THE DAY. SOUTH-SOUTHWEST FLOW ALOFT DEVELOPS AND
INCREASES WED AFT INTO WED NIGHT, WITH SHOWER AND THUNDERSTORM
CHANCES INCREASES OVER THE DAKOTAS, WITH THE BETTER CHANCES
LIKELY NEAR THE SFC TROUGH AXIS OVER THE EAST. SPC PREDICTABLY
HAS US IN THE GENERAL T-STORM OUTLOOK FOR DAY3 (WED/WED NIGHT).
THE BASE OF THE WESTERN CONUS TROUGH IS STILL FAVORED TO LIFT
NORTHEAST INTO THE NORTHERN PLAINS AND MORPH INTO A CLOSED LOW
ON THURSDAY, FOLLOWED BY ANOTHER NORTHERN STREAM CLOSED LOW
DEVELOPING INTO OUR REGION FRIDAY AND SATURDAY. PERIODS WITH THE
HIGHEST POPS ARE THU-FRI, WITH MORE UNCERTAINTY INTO THE WEEKEND
(DEPENDING ON THE POSITION OF THE UPPER LOW...HOW FAR NORTH OR
SOUTH). THUS AN ACTIVE AND COOLER WEATHER PATTERN WILL END THE
WORK WEEK AND CONTINUE INTO THE WEEKEND, WITH HIGH TEMPERATURES
IN THE 30S AND 40S FORECAST FRI-SUN, AND LOWS IN THE 20S. WE
STILL EXPECT RAIN CHANGING TO A MIX AND EVENTUALLY ALL SNOW
THURSDAY NIGHT-FRIDAY AM AS COLDER AIR IS PULLED SOUTH INTO
NORTH DAKOTA WITH THE INITIAL LOW. STILL TOO EARLY TO DIVE INTO
DETAILS WITH THIS DYNAMIC PERIOD, BUT NBM IS TRENDING HIGHER
WITH SNOW TOTALS BUT STILL NOTHING RIDICULOUS. AS THE LOWS WIND
UP, STRONG WINDS ARE ALSO FORECAST BOTH THURSDAY AND FRIDAY, AND
WILL ALSO LIKELY LINGER INTO SATURDAY. WILL KEEP A MENTION OF
THIS IN THE HWO.
AVIATION /12Z TAFS THROUGH 12Z TUESDAY/
ISSUED AT 612 AM CDT MON APR 20 2026
VFR CONDITIONS ARE EXPECTED THROUGH THE 12Z FORECAST PERIOD.
SOME HIGH LEVEL CLOUDS WILL STREAM ALOFT AT TIMES, ALONG WITH
SKC CONDITIONS AS WELL. SOUTHERLY WINDS WILL BECOME WEST
FOLLOWED BY NORTHWEST THROUGH TODAY AND THIS EVENING AS A FRONT
MOVES SOUTHEAST ACROSS THE REGION. LOW LEVEL WIND SHEAR WILL BE
PRESENT CENTRAL AND EAST THROUGH AROUND 15Z THIS MORNING.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...JONES
DISCUSSION...NH
AVIATION...NH
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