940
FXUS63 KBIS 100022
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
722 PM CDT FRI MAY 9 2025
KEY MESSAGES
- NEAR-SURFACE SMOKE WILL REDUCE VISIBILITY ACROSS CENTRAL
NORTH DAKOTA THIS EVENING.
- UNSEASONABLY HOT THIS WEEKEND INTO EARLY NEXT WEEK, WITH
WIDESPREAD HIGHS IN THE 90S. SEVERAL MAXIMUM TEMPERATURE
RECORDS COULD BE BROKEN.
- CRITICAL FIRE WEATHER CONDITIONS ACROSS WESTERN AND MOST OF
CENTRAL NORTH DAKOTA ON SATURDAY.
- WINDY ACROSS CENTRAL AND EASTERN NORTH DAKOTA SUNDAY AND
MONDAY, WITH NEAR-CRITICAL TO CRITICAL FIRE WEATHER
CONDITIONS.
- THERE IS A 20 TO 30 PERCENT CHANCE OF THUNDERSTORMS ACROSS
WESTERN AND NORTH CENTRAL NORTH DAKOTA PRIMARILY DURING THE
EVENING HOURS ON SUNDAY AND MONDAY. A FEW STORMS COULD BECOME
STRONG.
- HIGHER CHANCES FOR RAIN AND MUCH COOLER TEMPERATURES RETURN
FOR THE SECOND HALF OF NEXT WEEK.
UPDATE
ISSUED AT 719 PM CDT FRI MAY 9 2025
THE MAIN FORECAST CONCERN FOR THIS EVENING IS TRACKING NEAR-SURFACE
SMOKE DRIFTING WESTWARD INTO CENTRAL NORTH DAKOTA. VISIBILITY IN THE
2 TO 4 MILE RANGE HAS ROUTINELY BEEN OBSERVED WITHIN THE MOST HIGHLY
CONCENTRATED PLUME OF SMOKE. HIGH-RESOLUTION MODELING DOES SIMULATE
A DISPERSAL OF THE SMOKE LATER THIS EVENING INTO THE OVERNIGHT
HOURS, BUT SATELLITE TRENDS SUGGEST THE SMOKE WILL AT LEAST MAKE IT
TO THE HIGHWAY 83 CORRIDOR BETWEEN 8 AND 9 PM.
LATEST CAMS HAVE INCREASED PROBABILITIES OF SCATTERED SHOWER
FORMATION FROM CENTRAL INTO EASTERN NORTH DAKOTA LATE TONIGHT INTO
SATURDAY MORNING IN RESPONSE TO INCREASING WARM AIR ADVECTION DRIVEN
BY A STRONG LOW LEVEL JET. CLOUD BASES LOOK TO BE AROUND 10,000 FT
THOUGH. A 15 TO 20 PERCENT CHANCE OF SHOWERS WAS ADDED TO AREAS
INCLUDING AND SURROUNDING THE TURTLE MOUNTAINS, DEVILS LAKE BASIN,
AND NORTHERN JAMES RIVER VALLEY FROM AROUND 6 TO 10 AM CDT TOMORROW
MORNING.
DISCUSSION
ISSUED AT 315 PM CDT FRI MAY 9 2025
CURRENTLY, QUASI-ZONAL UPPER LEVEL FLOW REMAINS OVER THE
NORTHERN PLAINS, WITH AN AREA OF SFC HIGH PRESSURE DRIFTING EAST
ACROSS THE FAR SOUTHERN PRAIRIE PROVINCES OF SASKATCHEWAN
AND MANITOBA. NORTH-NORTHEASTERLY WINDS THIS AFTERNOON, WITH
OCCASIONALLY GUSTS TO AROUND 20 MPH THANKS TO PRESSURE RISES,
MIXING, AND GRADIENT FORCING. RH VALUES HAVE AGAIN DROPPED,
RANGING MAINLY IN THE 20-30 PERCENT RANGE. WILL CONTINUE TO
MENTION NEAR-CRITICAL FIRE WEATHER IN THE JAMES RIVER VALLEY.
FLOW ALOFT BECOMES MORE WEST-NORTHWESTERLY TONIGHT, AS AN UPPER
LEVEL RIDGE STARTS TO REBUILD ACROSS THE WESTERN CONUS WITH THE
AXIS NEAR THE ROCKIES. SFC WINDS BECOME MORE SOUTHEASTERLY AS
THE SFC HIGH CONTINUES EAST AND AS SFC LOW PRESSURE DEVELOPS
EAST OF THE NORTHERN ROCKIES.
THE AFOREMENTIONED UPPER LEVEL RIDGE CONTINUES TO REBUILD
ACROSS THE NORTHERN PLAINS OVER THIS COMING WEEKEND, WITH
INCREASING SOUTHERLY FLOW ACROSS THE DAKOTAS. TEMPERATURES
ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL WARM WELL INTO THE
80S TO MID 90S BOTH DAYS (WARMEST SUNDAY AND MONDAY WHEN
MID/UPPER 90S WILL BE POSSIBLE AS BOUNDARY LAYER TEMPS
INCREASE). RECORD HIGH TEMPERATURES ARE IN THE MID 90S, SO WELL
WITHIN REACH. LACK OF ANY DECENT MOISTURE RETURN WILL MAINTAIN
OUR VERY DRY BOUNDARY LAYER CONDITIONS, WITH PERCENT MINIMUM
HUMIDITY SATURDAY THROUGH MONDAY REMAINING IN THE TEENS TO LOWER
20S. SFC LOW/FRONTAL BOUNDARY WILL BE MAINLY TO OUR WEST ON
SATURDAY, RESULTING IN GUSTY SOUTHERLY WINDS OVER MUCH OF THE
LOCAL REGION, WHICH WILL ELEVATE FIRE WEATHER CONCERNS AND
NECESSITATE THE ISSUANCE OF A RED FLAG WARNING FOR WESTERN AND
MUCH OF CENTRAL ND. STILL HESITANT TO PUT UP ANY HEADLINES SOUTH
CENTRAL (EAST OF THE MISSOURI) INTO THE JAMES VALLEY, WITH LIVE
FUEL MOISTURE THERE STILL ELEVATED. HOWEVER, THE PERSISTENT DRY
CONDITIONS SHOULD HAVE AN IMPACT ON THE 1-100 HOUR FUELS
DESPITE THE GREENUP THERE EVENTUALLY.
THE OVERLAP OF DRY/WINDY WEATHER WITH RECEPTIVE FUELS WILL
CONTINUE TO RESULT IN TRICKY HEADLINE DECISIONS FOR BOTH SUNDAY
AND MONDAY. BOTH DAYS THE STRONGEST WINDS ARE STILL FORECAST
OVER OUR SOUTHEAST AS THE SFC TROUGH BECOMES ORIENTATED FROM
SOUTHWEST TO NORTHEASTERN ND, ALONG WITH WIDESPREAD MIN RH
VALUES 15-20%. BUT, THIS IS ALSO WHERE HRB IS HIGHEST (MORE
GREEN/LESS RECEPTIVE FUELS), AND OUR FIRE BEHAVIOR TOOLS STILL
GIVE US ZERO HOURS OF RED FLAG CONDITIONS AND RATE OF SPREAD
RELATIVELY LOW. MONDAY IS BASICALLY A CARBON COPY OF SUNDAY. AS
MENTIONED THOUGH, THE PERSISTENT DRY CONDITIONS SHOULD START TO
IMPACT THESE FUELS TO SOME DEGREE. FOR NOW WILL CONTINUE TO
MENTION NEAR-CRITICAL TO CRITICAL FIRE WEATHER SUNDAY AND MONDAY
IN THE HWO.
RIDGE NUDGES EAST SUNDAY NIGHT INTO MONDAY AS A LARGE AREA OF
UPPER LEVEL LOW PRESSURE MOVES INTO THE PACIFIC NORTHWEST.
EMBEDDED DISTURBANCES IN SOUTHWEST FLOW WILL BRING A CHANCE FOR
SHOWERS AND THUNDERSTORMS TO WEST/CENTRAL ND SUNDAY NIGHT WITH
THE SFC TROUGH QUASI-STATIONARY. AMPLE CAPE AND SHEAR WILL SEE A
MARGINAL THREAT FOR SEVERE WEATHER THIS PERIOD. UPPER LOW
MORPHS INTO A LONG WAVE TROUGH OVER THE WESTERN CONUS EARLY NEXT
WEEK, MAINTAINING SOUTHWESTERLY FLOW FOR OUR REGION. ADDITIONAL
EMBEDDED ENERGY LOOKS TO BRING A CHANCE OF SHOWERS/STORMS MON
NIGHT. SOUTHWEST FLOW REMAINS IN PLACE FOR MUCH OF THE WEEK,
WITH THE BASE OF THE UPPER TROUGH EVENTUALLY EJECTING NORTHEAST
THROUGH THE GREAT PLAINS AFTER WED. THIS FLOW PATTERN FAVORS
TEMPERATURES TRENDING COOLER ALONG WITH BETTER AND WIDESPREAD
PRECIPITATION CHANCES ACROSS WESTERN AND CENTRAL NORTH DAKOTA,
ESPECIALLY WHEN THE MAIN WAVE MOVES THROUGH.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 719 PM CDT FRI MAY 9 2025
A PLUME OF NEAR-SURFACE SMOKE CAUSING MVFR TO IFR VISIBILITY
REDUCTIONS WILL CONTINUE MIGRATING WESTWARD ACROSS CENTRAL
NORTH DAKOTA THIS EVENING, BUT IS FORECAST TO DISPERSE HEADING
INTO THE OVERNIGHT HOURS. ASIDE FROM THE SMOKE, VFR CONDITIONS
ARE EXPECTED THROUGH THE FORECAST PERIOD. A FEW SCATTERED
SHOWERS COULD DEVELOP FROM CENTRAL INTO EASTERN NORTH DAKOTA
LATE TONIGHT INTO SATURDAY MORNING. WINDS WILL GRADUALLY TURN TO
THE SOUTHEAST AROUND 10 KTS THROUGH TONIGHT, THEN BECOME MORE
SOUTHERLY AND INCREASE TO AROUND 20 KTS WITH GUSTS AS HIGH AS 30
KTS ON SATURDAY.
FIRE WEATHER
ISSUED AT 315 PM CDT FRI MAY 9 2025
NEAR-CRITICAL FIRE WEATHER CONDITIONS CONTINUE THROUGH EARLY THIS
EVENING ACROSS THE JAMES RIVER VALLEY AND VICINITY. ALTHOUGH
FUELS ARE FAIRLY GREEN, AFTERNOON RELATIVE HUMIDITY DIPPING INTO
THE 20 TO 25 PERCENT RANGE WILL COMBINE WITH NORTH-NORTHEAST WINDS
AT 20 TO 30 MPH. CONDITIONS IMPROVE RAPIDLY THIS EVENING.
FIRE WEATHER CONCERNS INCREASE THIS WEEKEND INTO EARLY NEXT WEEK,
WITH NEAR-CRITICAL TO CRITICAL CONDITIONS POSSIBLE DURING THE
DAYTIME HOURS EACH DAY. FOR SATURDAY, FIRE WEATHER TRENDS ARE
ELEVATED, AS WIDESPREAD GUSTY SOUTHERLY WINDS WILL COMBINE WITH
PERCENT MINIMUM RELATIVE HUMIDITY IN THE TEENS TO RESULT IN
CRITICAL FIRE WEATHER OVER WESTERN AND MUCH OF CENTRAL NORTH
DAKOTA (RED FLAG WARNING HAS BEEN ISSUED FOR THESE AREAS).
BUFKIT SOUNDINGS LOOK SIMILAR TO THURSDAY, WHERE 20-25 KTS ARE
CLOSE TO THE SFC IN THE MIXED LAYER, AND STRONG MIXING IS
EXPECTED. NOT EXPECTING ANY CONVECTION/DRY STORMS HOWEVER. NEAR
SFC CONDENSATION PRESSURE DEFICITS WEST WILL INCREASE THE
PROBABILITY FOR MIN RH VALUES TO NEAR 10 PERCENT IF NOT THE
UPPER SINGLE DIGITS. FOR SOUTH CENTRAL NORTH DAKOTA AND THE
JAMES RIVER VALLEY, NEAR-CRITICAL FIRE WEATHER CONDITIONS ARE
FORECAST ON SATURDAY WHERE 1-100 HOUR FUELS ARE LESS RECEPTIVE
TO FIRE SPREAD.
FOR SUNDAY AND MONDAY, DRY CONDITIONS PERSIST, WITH AFTERNOON
PERCENT MINIMUM RELATIVE HUMIDITY IN THE TEENS TO LOWER 20S AND
AFTERNOON TEMPERATURES IN THE UPPER 80S AND 90S. WE'RE STILL
SEEING THE LOWER RH POTENTIAL WEST, AND THIS TIME NOT COLLOCATED
WITH THE STRONGEST WINDS, WHICH WILL GENERALLY BE OVER SOUTH
CENTRAL AND EASTERN NORTH DAKOTA (INCLUDING THE JAMES RIVER
VALLEY AND VICINITY) BOTH DAYS. THE STRONGER WINDS WILL ALSO BE
WHERE THE 1-100 HOUR FUEL MOISTURE IS HIGHER. HOWEVER, AS
PREVIOUSLY MENTIONED, THE PERSISTENT DRY CONDITIONS COUPLED
WITH RECEPTIVE DEAD FUELS IN SOME AREAS WILL STILL ELEVATE FIRE
WEATHER CONCERNS TO WHERE ADDITIONAL HEADLINES MAY BE NEEDED
SUNDAY AND MONDAY.
PRECIPITATION CHANCES AND COOLER TEMPERATURES RETURN MONDAY
EVENING THROUGH AT LEAST MIDWEEK, ALONG WITH RELATIVE HUMIDITY
TRENDING WETTER.
BIS WATCHES/WARNINGS/ADVISORIES
RED FLAG WARNING FROM NOON CDT /11 AM MDT/ TO 9 PM CDT /8 PM
MDT/ SATURDAY FOR NDZ001>005-009>013-017>021-031>034-040>045.
UPDATE...HOLLAN
DISCUSSION...NH
AVIATION...HOLLAN
FIRE WEATHER...NH
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