856
FXUS63 KBIS 160408
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1008 PM CST FRI NOV 15 2024
KEY MESSAGES
- TEMPERATURES TREND COOLER THIS WEEKEND WITH A 90 PERCENT OR
GREATER CHANCE OF PRECIPITATION IN THE NORTH AND WEST CENTRAL
TONIGHT THROUGH SATURDAY NIGHT. SNOW MAY BE MIXED IN AT TIMES,
ESPECIALLY IN THE NORTHWEST, WHERE ACCUMULATIONS OF 1 TO 3
INCHES OF WET SNOW ARE POSSIBLE.
- TEMPERATURES WILL REBOUND SUNDAY AND MONDAY TO NEAR NORMAL
THEN TREND COOLER FOR THE MIDDLE OF NEXT WEEK.
- ADDITIONAL RAIN AND SNOW CHANCES RETURN BY THE MIDDLE OF NEXT
WEEK. THERE ALSO IS AN INCREASED PROBABILITY FOR SNOW
ACCUMULATIONS NEXT WEEK.
UPDATE
ISSUED AT 1008 PM CST FRI NOV 15 2024
THE ONLY GRID UPDATES THIS EVENING WERE MINOR TWEAKS TO SKY
COVER AND POPS THROUGH 12Z SATURDAY. MID AND HIGH LEVEL CLOUDS
CONTINUE TO LIFT NORTH AND THERE'S QUITE A BIT OF CLEAR SKY
ALONG AND SOUTH OF I-94 LATE THIS EVENING. HOWEVER, THE LOW
STRATUS THAT WE MENTIONED IN THE EARLY EVENING UPDATE IS NOW
DEVELOPING OVER SOUTHEAST NORTH DAKOTA AND IS CURRENTLY MOVING
INTO JAMESTOWN. LATEST RAP LOW LEVEL MOISTURE GUIDANCE SHOWS
THIS STRATUS SPREADING WEST NORTHWEST INTO CENTRAL ND, TOWARDS
BISMARCK AND MINOT, AND THEN GETTING PULLED DOWN INTO SOUTHWEST
ND TOWARDS 12 UTC SATURDAY. WE UTILIZED A BLEND OF SHORT TERM
GUIDANCE WITH THE PREVIOUS FORECAST FOR POPS THROUGH 12 UTC.
VERY LITTLE CHANGES HERE, BUT DID CUT BACK BIT ON THE EASTWARD
EXTENT OF SLIGHT CHANCE POPS OVERNIGHT.
WE DID ISSUE A SPS FOR NORTHWEST AND NORTH CENTRAL NORTH DAKOTA.
WE KEPT MESSAGING QUITE SIMILAR TO AFTERNOON MESSAGING. WE DID
MENTION SOME ACCUMULATIONS UP TO 5 INCHES IN THE BANDED WORDING.
LOOKING AT SOME OF THE NEWER GUIDANCE JUST COMING IN, THE SHORT
TERM GUIDANCE CONTINUES TO IMPRESS WITH THE HRRR/RAP/NAMNEST ALL
SHOWING LIQUID QPF OF A HALF TO THREE QUARTERS OF AN INCH OVER
FAR NORTHWEST ND. THE LATEST NBM IS A LESS IMPRESSIVE WITH MORE
IN THE AREA OF A QUARTER TO A HALF INCH OF QPF FROM WATFORD CITY
AND WILLISTON NORTHEAST TO CROSBY AND BOWBELLS, AND THEN EAST
ALONG THE INTERNATIONAL BORDER INTO NORTHERN BOTTINEAU COUNTY.
THE POTENTIAL FOR BANDED PRECIPITATION STILL EXISTS WITH THIS
SYSTEM. THE LATEST RAP SHOWS A STEADY FLUX OF WARM ADVECTION
INTO NORTHWEST NORTH DAKOTA SATURDAY MORNING. THIS IS CONGRUENT
WITH STRONG QVECTOR DIVERGENCE, AND STEEP 70H-50H LAPSE RATES.
IN ADDITION, MODERATE 85H FG FORCING IS PRESENT OVER NORTHWEST
NORTH DAKOTA IN THE 12-17 UTC TIMEFRAME AND STRONG 70H FG
FORCING IS LOCATED OVER FAR NORTHWEST NORTH DAKOTA FROM AROUND
13-16 UTC. THERE SHOULD BE SUFFICIENT MOISTURE AVAILABLE DURING
THIS TIMEFRAME AS WELL. IN ADDITION, THERE IS A MODEST BUT
DISTINCT TROWAL LIFTING OVER THIS AREA AND THE 70H LOW ALSO
TRACKS FROM FAR EAST CENTRAL MT INTO NORTHWEST/NORTH CENTRAL
NORTH DAKOTA. WITH OR RECENT WARM SURFACE TEMPERATURES, THERE IS
ALWAYS A QUESTION AS TO HOW MUCH SNOW WILL ACCUMULATE, BUT
GIVEN THE STRONG SIGNALS FOR POSSIBLE BANDING, THINK THERE WOULD
BE A POSSIBILITY TO GET A FEW HOURS OF ACCUMULATING SNOWS, WITH
LOCALLY HIGHER AMOUNTS IN BANDS OF SNOW. THE 00Z ECMWF SA PAGE
WAS ALSO INTERESTING, WITH A STRONG QPF SIGNAL OVER FAR
SOUTHEAST SASKATCHEWAN AND INTO FAR NORTHWEST NORTH DAKOTA. THE
SHIFT OF TAILS WAS ALSO GREATER THAN 2 OVER FAR NORTHWEST NORTH
DAKOTA, UPPING THE ANTI SO TO SPEAK FOR THE POTENTIAL OF AN
EXTREME EVENT. THE WPC ALSO HINTED AT BANDED SNOW OVER THE
NORTHWEST WITH THEIR SNOWBAND PROBABILITY TRACKER.
BEING THAT THE NEW GUIDANCE IS JUST COMING IN AND SNOW DOES NOT
REALLY LOOK TO GET GOING UNTIL AROUND 12 UTC, WE FELT THE SPS
WOULD BE A NICE NEXT STEP. SHOULD GUIDANCE CONTINUE TO ADVERTISE
HIGHER QPF AND AMOUNTS, A SPS COULD BE ISSUED ON THE OVERNIGHT
SHIFT. IF NOT, THE SPS CONTINUES OUR LATEST MESSAGING. WE'LL SEE
WHAT THE OVERNIGHT SHIFT BRINGS.
UPDATE
ISSUED AT 521 PM CST FRI NOV 15 2024
NO SIGNIFICANT CHANGES FOR THE EARLY EVENING UPDATE. MID AND
HIGH CLOUDS PRETTY MUCH COVER THE STATE, WITH SOME BREAKS
POSSIBLE THIS EVENING SOUTHWEST AND SOUTH CENTRAL. SHOULD BE A
QUIET EVENING WITH MILD TEMPERATURES AND AN EASTERLY SURFACE
FLOW. LOW STRATUS IS EXPECTED TO DEVELOP TONIGHT AND COULD SNEAK
INTO THE JAMES RIVER VALLEY LATER THIS EVENING, BUT MORE LIKELY
AFTER MIDNIGHT.
DISCUSSION
ISSUED AT 326 PM CST FRI NOV 15 2024
TEMPERATURES HAVE REACHED 50S ACROSS MUCH OF THE STATE THIS
AFTERNOON. TODAY WILL BE THE LAST WELL ABOVE NORMAL NORMAL DAY
FOR A WHILE AS THE PATTERN WILL BEGIN TO CHANGE. HIGH CLOUDS
CONTINUE TO STREAM IN AS AN UPPER LEVEL WAVE APPROACHES THE
REGION. OVERNIGHT LOWS ARE FORECAST TO DROP DOWN INTO THE LOWER
20S TO LOWER 30S.
AN UPPER LEVEL TROUGH WILL BRING RAIN TO PORTIONS OF WESTERN AND
CENTRAL NORTH DAKOTA SATURDAY. THE AREA WITH THE HIGHEST
LIKELIHOOD FOR PRECIPITATION IS THE NORTHWEST WITH A 70-90
PERCENT CHANCE. WHILE THE SOUTHWEST TO THE NORTHEAST HAS A 30-50
PERCENT CHANCE OF PRECIPITATION AND THE SOUTHEAST HAS THE
LOWEST PROBABILITY FOR PRECIPITATION AROUND 10-15 PERCENT.
PRECIPITATION WILL LIKELY START OUT AS RAIN TRANSITIONING OVER
TO SNOW SATURDAY IN THE NORTHWEST AS COOLER AIR WRAPS AROUND
THE LOW. THERE COULD BE AN HOUR OR TWO OF FREEZING RAIN BEFORE A
SNOW MIXES IN. IF PRECIPITATION RATES INCREASE THERE IS A
CHANCE FOR SNOW ACCUMULATIONS TO START EARLIER INCREASING SNOW
ACCUMULATIONS. FORECAST SNOW ACCUMULATIONS ARE AROUND 1 TO 3
INCHES ARE POSSIBLE, WHILE LOCALLY HIGHER SNOW ACCUMULATIONS
ARE POSSIBLE FROM BANDED SNOW. SNOW RATIOS WILL BE ON THE LOWER
THAN 10:1 AT THE BEGINNING OF THE SNOW TRANSITION RESULTING IN
LOWER ACCUMULATIONS, BUT TOWARD THE END OF THE EVENT A 10:1
RATIO WILL BE MORE LIKELY. PATCHY DENSE FOG IS ALSO POSSIBLE
TONIGHT THROUGH TOMORROW MORNING IN PORTIONS OF THE JAMES RIVER
VALLEY AND SOUTHWESTERN NORTH DAKOTA.
TEMPERATURES WILL BEGIN TO TREND DOWN SATURDAY AS THE
AFOREMENTIONED UPPER LOW MOVES THROUGH REGION. HIGH
TEMPERATURES IN THE 30S NORTHWEST WHERE THE PRECIPITATION IS
WHILE THE SOUTHEAST COULD WARM INTO THE LOWER 50S. TEMPERATURES
WILL SLIGHTLY WARM BACK UP SUNDAY AND MONDAY AS A WEAK AMPLITUDE
RIDGE PASSES OVERHEAD. TEMPERATURES COULD REMAIN 5 TO 10
DEGREES ABOVE NORMAL SUNDAY AND MONDAY.
AN UPPER LEVEL LOW IS FORECAST TO MOVE ACROSS THE PLAINS NEXT
WEEK. THIS UPPER LEVEL LOWS TRACK HAS SHIFTED EVERY RUN
RESULTING IN LOW CONFIDENCE ON LOCATION AND TIMING. THIS DUE TO
AN AMPLIFICATION ISSUE THE MODELS ARE HAVING DUE TO AN OMEGA
BLOCK SET UP. THE NEWEST 12Z ENSEMBLES PROBABILITIES FOR SNOW
HAS INCREASED ACROSS THE REGION WITH A FEW SIGNIFICANT SNOW
ACCUMULATIONS OUTLIERS. RIGHT NOW PROBABILITIES REMAIN LOW FOR
SIGNIFICANT ACCUMULATIONS, BUT HAVE TRENDED SLIGHTLY UP. THE
NBM HAS INCREASED THE PROBABILITY OF 4 INCHES OF SNOW OR GREATER
FROM 20 TO 40 PERCENT. ONE THING WE KNOW ABOUT THIS SYSTEM IT
WILL BRING SOME COLDER CONDITIONS ACROSS THE REGION. THE NBM
25TH TO 75TH TEMPERATURE RANGE IS AROUND NEAR NORMAL TO BELOW
NORMAL COMPARED TO THE WELL ABOVE NORMAL WEATHER WE HAVE HAD THE
LAST WEEK.
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
ISSUED AT 1008 PM CST FRI NOV 15 2024
A STORM SYSTEM WILL BRING RAIN AND SNOW TO KXWA AND KMOT LATE
TONIGHT INTO SATURDAY MORNING WITH MVFR TO IFR VSBYS IN SNOW.
WIDESPREAD MVFR-IFR CEILINGS DEVELOPING AT REMAINING TAF SITES.
VFR CONDITIONS AT ALL TAF SITES EXCEPT KJMS TO BEGIN THE 06Z
TAF PERIOD WITH AN EASTERLY SURFACE FLOW AROUND 10 KNOTS. LLWS
HAS DROPPED SOUTH AND WILL NOT CARRY IT AT KJMS WITH THE 06Z TAF
ISSUANCE. LOW STRATUS AND FOG AROUND KJMS IS EXPECTED TO EXPAND
BACK WEST AND COULD IMPACT ALL TAF SITES LATE TONIGHT INTO
SATURDAY MORNING. RAIN, THEN A RAIN SNOW MIX WILL DEVELOP AT
KXWA, LIKELY TURNING TO ALL SNOW AND SPREADING EAST TO KMOT,
ENDING SATURDAY AFTERNOON OR EARLY EVENING. THE REMAINING TAF
SITES WILL ONLY SEE A PASSING CHANCE OF LIGHT RAIN OR SNOW ON
SATURDAY. EAST WINDS THIS EVENING WILL INCREASE TONIGHT AND
EVENTUALLY SHIFT WEST TO NORTHWEST 15 TO 30 KNOTS AT ALL TAF
SITES BY SATURDAY AFTERNOON, THEN DIMINISHING SATURDAY EVENING.
BIS WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...TWH
DISCUSSION...JOHNSON
AVIATION...TWH
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