395
FXUS63 KFGF 100300
AFDFGF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1000 PM CDT SAT AUG 9 2025
KEY MESSAGES
-A FEW THUNDERSTORMS ARE FORECASTED THE REST OF THIS AFTERNOON
INTO THE EVENING ACROSS NORTHEASTERN ND INTO NORTHWESTERN MN.
LIGHTNING WILL BE THE MAIN THREAT.
UPDATE
ISSUED AT 946 PM CDT SAT AUG 9 2025
SHOWERS AND A FEW BRIEF THUNDERSTORMS CONTINUE ACROSS NORTHWEST
MINNESOTA. LIMITED INSTABILITY AND SHEAR IS PREVENTING ANY
IMPACTS FROM ARISING. THE REASONABLE WORST CASE SCENARIO IS A
FEW LIGHTNING STRIKES AND THIS SHOULD REMAIN ISOLATED TO MAINLY
THE LAKE OF THE WOODS THROUGH BELTRAMI COUNTY AREAS. AS THE
FRONT PUSHES EAST TONIGHT, IMPACTS WILL CONTINUE TO DIMINISH
FROM WEST TO EAST.
UPDATE
ISSUED AT 704 PM CDT SAT AUG 9 2025
STRONG TO SEVERE STORMS CAPABLE OF WINDS TO 60 MPH AND BRIEF,
WEAK TORNADOES WILL BE POSSIBLE UNTIL AROUND 8 PM WITHIN THE
CENTRAL RED RIVER VALLEY INTO PORTIONS OF NORTHWEST MN.
RELATIVELY ROBUST CONVECTION HAS DEVELOPED WITHIN CENTRAL RED
RIVER VALLEY, UTILIZING AVAILABLE INSTABILITY MAINLY ROOTED IN
THE LOWEST LAYERS OF THE ATMOSPHERE. AT TIMES, THEY ARE
DISPLAYING MINI-SUPERCELLULAR CHARACTERISTICS, AS WELL AS BOWING
SEGMENTS, ALBEIT SPATIAL SMALL. STORM MOTIONS HAVE BEEN AROUND
50-60 MPH, PUSHED BY SIMILAR MAGNITUDE WINDS ALOFT. WHILE
POTENTIAL FOR DOWNDRAFT ACCELERATION IS LIMITED (DCAPE LESS THAN
800 J/KG), THE LOW LEVEL SHEAR IS STRONG. THIS MEANS MOMENTUM
TRANSFER OF WINDS ALOFT TOWARD THE SURFACE WITHIN THE
DOWNDRAFT MAY ALLOW WIND GUSTS TO 60 MPH. ONE SUCH CELL HAS BEEN
SAMPLED BY KMVX WITH 55KT OUTBOUNDS AT AROUND 1,000 FT ABOVE THE
GROUND.
ALSO OF NOTE IS POTENTIAL FOR FUNNELS/BRIEF WEAK TORNADOES GIVEN
LOW LEVEL SHEAR AND SUPERCELLULAR CHARACTERISTICS, COUPLED WITH
AMPLE AMBIENT VORTICITY AND LOW LEVEL INSTABILITY. MAIN LIMITING
FACTOR FOR THIS WOULD BE RELATIVELY DRY BOUNDARY LAYER, ALTHOUGH
NOT DRY ENOUGH TO NEGATE THE POTENTIAL. THIS WOULD BE DEPENDENT
UPON DISCRETE CONVECTION/MINI-SUPERCELLS TO LATCH ON TO ANY
BOUNDARY.
THE WINDOW OF STRONG TO SEVERE STORMS CLOSES AROUND SUNSET (8PM)
WITH THE LOSS OF DAYTIME HEATING AND LOSS OF INSTABILITY.
OTHERWISE, SCATTERED SHOWERS WILL PREVAIL ACROSS THE AREA INTO
EARLY EVENING BEFORE LOWERING IN COVERAGE. BREEZY WINDS TAME
AROUND SUNSET AS WELL.
DISCUSSION
ISSUED AT 316 PM CDT SAT AUG 9 2025
..SYNOPSIS
A LARGE CUTOFF LOW IS SPINNING OVER THE CANADIAN PRAIRIES THIS
AFTERNOON. THE TIGHTER PRESSURE GRADIENT ON THE SOUTHERN SIDE OF THE
LOW IS BRINGING WIND GUSTS UP TO ABOUT 30 MPH SO FAR TODAY. AS THIS
LOW PUSHES NORTH AND EAST THROUGH THE REST OF THE AFTERNOON AND
EVENING, THE HIGHER WINDS GUSTING TO 35 MPH OR SO SHOULD OVERSPREAD
THE RED RIVER VALLEY AND POINTS WEST. IN THE LOWS WAKE, FLOW WILL
BECOME NORTHWESTERLY. THIS NORTHWESTERLY FLOW WILL KEEP US IN A
QUIETER PATTERN WITH SEASONAL TEMPERATURES, BUT ALSO ADVECT IN
CANADIAN WILDFIRE SMOKE, REDUCING AIR QUALITY AND VISIBILITY
MIDDAY SUNDAY THROUGH MONDAY.
BY MIDWEEK, UPPER FLOW ONCE AGAIN BECOMES SOUTHWESTERLY AS A TROUGH
DIGS INTO THE NORTHERN ROCKIES AND A RIDGE SETS UP OVER THE NORTHERN
PLAINS. DEPENDING ON THE AMPLITUDE, PLACEMENT AND TIMING OF THESE
FEATURES, TEMPERATURES LATE WEEK MAY BE SLIGHTLY WARMER THEN
CURRENTLY FORECASTED. THIS IS SHOWN WELL BY THE SPREAD IN THE
NBM, WITH KGFK INDICATING A 9 DEGREE SPREAD FROM 81 TO 90 FOR
HIGH TEMPERATURES ON THURSDAY. A MORE AMPLIFIED PATTERN WOULD
ALSO ALLOW FOR MORE MOISTURE AND HEAT TO ADVECT NORTHWARD,
INCREASING THE POTENTIAL COVERAGE/SEVERITY OF ANY THUNDERSTORMS
THAT FORM THURSDAY AND FRIDAY.
..THUNDERSTORMS TODAY
STORMS ARE EXPECTED TO DEVELOP IN THE CYCLONIC FLOW THAT IS OVER
MUCH OF ND/NW MN THIS AFTERNOON. THE FAVORED LOCATION FOR
DEVELOPMENT IS IN NORTHEASTERN ND INTO NORTHWESTERN MN. AFTERNOON
HEATING HAS ALLOWED FOR 500 TO 1000 J/KG OF CAPE, ALBEIT SKINNY
ON SKEW-T'S, TO DEVELOP. EFFECTIVE SHEAR IS ALSO DECENT,
TOUCHING ON 30 KNOTS. WITH THE PROXIMITY TO THE UPPER LOW,
SURFACE VORTICITY IS PLENTIFUL, AND 3CAPE IS NEARING 100 J/KG.
MUCH OF THE CAPE AS INDICATED IN SOUNDING DATA IS BELOW THE
FREEZING LEVEL. ADD IN SHORTER STORMS DUE TO THE LOWER EL FROM
THE NEARBY UPPER LOW, HAIL ABOVE THE SIZE OF PEAS IS NOT MUCH OF
A CONCERN. BASED ON THE ENVIRONMENT, LIGHTNING WOULD BE THE
MAIN THREAT, BUT FUNNEL CLOUDS CANNOT BE RULED OUT WITH ANY
STORM THAT FORMS. THERE ARE PLENTY OF LIMITING FACTORS THOUGH,
THE MOST GLARING IS STORM MODE THAT WILL LIKELY BECOME MESSY IN
SHORT ORDER. THIS WILL BE SOMETHING TO MONITOR THROUGH THE
EVENING, BUT SEVERE WEATHER IS NOT ANTICIPATED.
AVIATION /00Z TAFS THROUGH 00Z MONDAY/
ISSUED AT 704 PM CDT SAT AUG 9 2025
POP UP SHOWERS/THUNDERSTORMS AND GUSTY WINDS CONTINUE TO BE THE
MAIN IMPACTS FOR THIS SET OF TAFS. SCATTERED SHOWERS/STORMS WILL
LESSEN IN COVERAGE BETWEEN 00Z-04Z BEFORE DIMINISHING.
GUSTS THIS AFTERNOON WILL BE BETWEEN 25 TO 30 KNOTS UNTIL
AROUND 02Z BEFORE LOWERING BELOW 15KT.
LOWERING CEILINGS ARE STILL FORECAST INTO THE EVENING,
ESPECIALLY AT KDVL, KGFK AND KTVF. HOWEVER, SMOKE WILL START
TO SPILL DOWN FROM CANADA BY LATE SUNDAY MORNING AT KDVL. BEYOND
THIS TAF PERIOD, SMOKE WILL OVERSPREAD THE REGION, WITH
VISIBILITY IMPACTS HARD TO DISCERN YET AT THIS RANGE.
FGF WATCHES/WARNINGS/ADVISORIES
ND...NONE.
MN...NONE.
UPDATE...CJ/PERROUX
DISCUSSION...RAFFERTY
AVIATION...CJ
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