504
FXUS63 KFGF 190442
AFDFGF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1142 PM CDT THU JUN 18 2026
KEY MESSAGES
- AFTER A FEW SHOWERS AND THUNDERSTORMS ON FRIDAY, TEMPERATURES
WILL SLOWLY WARM TO NEAR 80 BY LATE NEXT WEEK.
DISCUSSION
ISSUED AT 202 PM CDT THU JUN 18 2026
..SYNOPSIS
NORTHWEST FLOW REMAINS IN PLACE OVER THE NORTHERN HIGH PLAINS AND
UPPER MIDWEST THIS AFTERNOON. EMBEDDED IN NORTHWESTERLY FLOW WILL
BE A HANDFUL OF WEAK WAVES. THE MOST PROMINENT SHORTWAVE
PROPAGATES THROUGH FRIDAY. AS IT TRACKS THROUGH, A FEW SHOWERS
AND THUNDERSTORMS ARE FORECASTED TO DEVELOP. SEVERAL MORE WEAK
WAVES WILL TRAVERSE THE REGION LATE THIS WEEKEND INTO EARLY NEXT
WEEK AS NORTHWEST TO ZONAL FLOW CONTINUES. THIS WILL BRING
ADDITIONAL LOW CHANCES FOR SHOWERS AND THUNDERSTORMS TO START
THE WORK WEEK.
TEMPERATURES WILL REMAIN COOLER THEN AVERAGE THROUGHOUT MUCH OF THE
FORECAST PERIOD, ALTHOUGH BY MID TO LATE NEXT WEEK THE PATTERN DOES
SHIFT AS RIDGING BUILDS IN. THIS WILL FINALLY HELP US GET
TEMPERATURES BACK TO NEAR AVERAGE BY THURSDAY. WHILE THERE ARE SOME
DIFFERENCES FROM ENSEMBLE MEMBER TO ENSEMBLE MEMBER OF THE RIDGES
STRENGTH, THERE IS SURPRISINGLY LITTLE SPREAD IN TEMPERATURES FROM
THE NBM. FOR EXAMPLE, AT KGFK, THE 25TH AND 75 PERCENTILES FOR NEXT
THURSDAY ARE 75 AND 80 DEGREES. AVERAGE FOR THE DATE IS 78 DEGREES.
SO, WHILE WARMER THEN THE CURRENT COOL SPELL WE ARE EXPERIENCING,
EVEN RIDGING WILL ONLY BRING TEMPERATURES UP TO NEAR AVERAGE.
..SHOWERS AND THUNDERSTORMS FRIDAY
A WAVE PROPAGATING SOUTHEASTWARD FROM SASKATCHEWAN THURSDAY NIGHT
QUICKLY INTO MINNESOTA BY FRIDAY AFTERNOON WILL BE THE TRIGGER FOR
SHOWER AND THUNDERSTORM DEVELOPMENT BEGINNING TONIGHT. AS THE LOW
SWINGS THROUGH THE FA LATE FRIDAY MORNING INTO THE AFTERNOON, AN
AIRMASS CHARACTERIZED BY UP TO 1000 J/KG OF MUCAPE AND 20 TO 30
KNOTS OF EFFECTIVE SHEAR WILL ALLOW FOR SHOWERS AND THUNDERSTORMS TO
BLOSSOM. THE SPEED AT WHICH THE LOW TRACKS THROUGH THE FA WILL
DETERMINE WHERE THE STRONGEST THUNDERSTORMS INITIATE. A QUICKER
LOW WILL WHISK MUCH OF THE INSTABILITY EASTWARD BY AFTERNOON,
LEAVING ALL BUT OUR FAR SOUTHEASTERN COUNTIES WITH ANY CHANCE
FOR A STRONGER STORM. A SLOWER SYSTEM WOULD ALLOW INSTABILITY TO
REMAIN OVER MORE OF THE REGION, AND STORMS TO DEVELOP FURTHER
WEST, PROBABLY CLOSER TO THE MN SIDE OF THE RED RIVER VALLEY.
THE BEST OVERLAP IN SHEAR AND INSTABILITY IN EITHER SCENARIO IS
IN WEST CENTRAL MN (PARK RAPIDS, DETROIT LAKES, WADENA, FERGUS
FALLS AREAS). IF A THUNDERSTORM WERE TO BECOME STRONG TO
MARGINALLY SEVERE, IT WOULD BE IN THIS REGION DURING THE MID TO
LATE AFTERNOON HOURS, WITH JUST SUFFICIENT SPEED SHEAR FOR HAIL
TO BE THE PRIMARY THREAT. THEREFORE, THE STORM PREDICTION CENTER
HAS PLACED OUR FAR SOUTHEASTERN COUNTIES IN A MARGINAL, LEVEL 1
OUT OF 5 RISK FOR SEVERE THUNDERSTORMS FRIDAY AFTERNOON.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 1138 PM CDT THU JUN 18 2026
AN INITIAL BAND OF SHOWERS IS WORKING ITS WAY THROUGH CENTRAL
NORTH DAKOTA AND MAY IMPACT ALL TAF SITES AS IT PROGRESSES
EASTWARD. HAVING SAID THAT, PRECIPITATION SHOULD REMAIN FAIRLY
SHORT-LIVED INITIALLY AND IMPACTS TO VISIBILITY SHOULD REMAIN
MINIMAL. LIGHTNING RISK SHOULD ALSO REMAIN FAIRLY LIMITED AND
CARRIES A LOW PROBABILITY OF TERMINAL IMPACTS. VFR CONDITIONS
WILL PREVAIL THROUGH THE EARLY MORNING HOURS AS WELL EVEN WITH
FALLING CEILINGS.
AS WE APPROACH 12Z, MORE WIDESPREAD SHOWERS ARE EXPECTED TO
DEVELOP ACROSS NORTHWEST MINNESOTA, AGAIN WITH A LIMITED
LIGHTNING RISK. FURTHER WEST, CEILINGS ARE LIKELY TO FALL IN
EASTERN NORTH DAKOTA, WITH THE POTENTIAL FOR MVFR CEILINGS TO
BRIEFLY IMPACT DVL. CEILINGS SHOULD QUICKLY RISE THROUGH THE
LATE MORNING HOURS SO THIS PERIOD SHOULD BE FAIRLY BRIEF SHOULD
THIS ARISE. A BREAK IN PRECIPITATION OCCURS EARLY TOMORROW
AFTERNOON BEFORE ADDITIONAL SHOWERS ARE LIKELY TO DEVELOP. WITH
STRONGER INSTABILITY EXPECTED TOMORROW AFTERNOON, THUNDERSTORMS
HAVE A GREATER CHANCE TO IMPACT ALL TAF SITES, ESPECIALLY GFK
AND FAR. FOR THIS REASON, PROB30 GROUPS WITH TSRA WILL BE ADDED
TO THE FORECAST FOR GFK/FAR. SHOWERS/STORMS MAY LINGER THROUGH
THE EARLY EVENING HOURS BUT THE BULK OF ACTIVITY SHOULD SHIFT
EASTWARD TOMORROW EVENING. STRONGER NORTHWESTERLY WINDS WILL BE
LEFT IN ITS WAKE, GENERALLY SUSTAINED BETWEEN 10-20 KNOTS WITH
OCCASIONAL GUSTS TO 25 KNOTS, ALTHOUGH FREQUENCY OF GUSTS SHOULD
REMAIN LIMITED AS SUNSET APPROACHES.
FGF WATCHES/WARNINGS/ADVISORIES
ND...NONE.
MN...NONE.
DISCUSSION...RAFFERTY
AVIATION...PERROUX
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