711
FXUS63 KFGF 070442
AFDFGF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1142 PM CDT MON MAY 6 2024
KEY MESSAGES
- STRONG SOUTHEAST WINDS WILL CONTINUE THIS AFTERNOON INTO
TONIGHT ACROSS EASTERN NORTH DAKOTA AND ADJACENT PORTIONS OF
MINNESOTA, WITH GUSTS UP TO 50 MPH AT TIMES.
- SHOWERS AND ISOLATED THUNDERSTORMS WILL AFFECT THE REGION THROUGH
WEDNESDAY.
UPDATE
ISSUED AT 1142 PM CDT MON MAY 6 2024
STARTING TO SEE MORE COVERAGE OF SHOWERS AND ISOLATED STORMS
WITHIN THE RED RIVER VALLEY. THIS IS CONNECTED TO A LONG LINE OF
SHOWERS/STORMS EXTENDING ALL THE WAY DOWN INTO THE CENTRAL
PLAINS, WHICH IS GENERALLY EXPECTED TO LIFT NORTHWARD OVERNIGHT.
THE CAMS ARE INDICATING MOST OF THIS ACTIVITY MOVING INTO THE
HIGHWAY 200 CORRIDOR AND NORTHWARD BY TUESDAY MORNING. SO FAR,
NDAWN STATIONS ARE INDICATING A FAIR COVERAGE OF 0.10 TO 0.50
INCHES OF RAIN ALONG AND WEST OF THE RED RIVER VALLEY. AS THIS
LINE OF SHOWERS/STORMS CONTINUES TO LIFT NORTHWARD, THESE
AMOUNTS MAY BE MORE ON THE LOWER END OF THAT RANGE (MORE SO 0.10
TO 0.25 INCHES).
UPDATE
ISSUED AT 947 PM CDT MON MAY 6 2024
WIND SPEEDS QUICKLY DROPPED OFF AT QUITE A FEW SITES RIGHT
AROUND 9 PM, SO WAS ABLE TO CANCEL MOST OF THE WIND ADVISORY A
LITTLE EARLY. STILL HAVE SEEN A FEW HIGHER GUSTS IN THE GWINNER
TO VALLEY CITY CORRIDOR, SO KEPT THE ADVISORY GOING YET THERE.
DID SEE THE LATEST OBSERVATION AT GWINNER REALLY DROPPED NOW
TOO, SO MAY BE ABLE TO CANCEL THE LAST 3 COUNTIES A LITTLE EARLY
TOO. HOWEVER, WILL WAIT FOR ANOTHER ROUND OF TOP OF THE HOUR
OBSERVATIONS BEFORE DOING SO.
UPDATE
ISSUED AT 620 PM CDT MON MAY 6 2024
NO HUGE CHANGES WITH THIS FORECAST UPDATE. WILL SLOW DOWN THE
ARRIVAL OF LIKELY PRECIPITATION CHANCES FOR ANOTHER FEW HOURS.
SEEMS LIKE THERE IS MORE AREAL COVERAGE OF SHOWERS/STORMS
ORGANIZING OVER EASTERN SOUTH DAKOTA NOW, BUT IF THEY HOLD
TOGETHER AS IS, IT WILL BE A FEW MORE HOURS UNTIL THEY ARRIVE IN
THE SOUTHERN FA. THERE IS SOME LIGHTNING ACTIVITY OVER
SOUTHEAST NORTH DAKOTA, BUT NOTHING TOO CONCENTRATED OR LONG
LASTING. AS THE PREVIOUS SHIFT NOTED, 850MB WINDS CRANK UP TO
AROUND 60 KNOTS AROUND OR AFTER SUNDOWN (AND CONTINUE THROUGH
MOST OF THE NIGHT), SO THE ECHOES ON RADAR ARE MOVING VERY
FAST.
DISCUSSION
ISSUED AT 212 PM CDT MON MAY 6 2024
..SYNOPSIS
A STRONG UPPER LEVEL TROUGH IS MOVING OUT OF THE ROCKIES INTO
THE CENTRAL AND NORTHERN HIGH PLAINS AS SEEN ON WATER VAPOR
SATELLITE IMAGERY. THIS IS HELPING RAPID DEEPENING OF A SURFACE
LOW IN THE WESTERN DAKOTAS, GENERATING AN EXPANSIVE INCREASED
WIND FIELD AS WELL AS DRAWING IN MOISTURE AND LIFT INTO THE
REGION. BY TUESDAY AFTERNOON, THE UPPER TROUGH CLOSES INTO AN
UPPER LOW, BECOMING STACKED ON TOP OF SURFACE LOW HALTING ITS
DEEPENING/STRENGTHENING. THIS ALSO ALLOWS THE LOW TO STALL OVER
THE DAKOTAS BY TUESDAY. A SECOND UPPER TROUGH MOVING THROUGH
THE INTERMOUNTAIN WEST WEDNESDAY WILL THEN HELP THE UPPER LOW
MOVE SOUTHEAST OUT OF THE DAKOTAS BY WEDNESDAY NIGHT.
NORTHWEST FLOW ALOFT THEN DEVELOPS WITH THE HELP OF UPPER
RIDGING OVER THE WEST AROUND FRIDAY, WITH ENSEMBLE GUIDANCE ALL
DEPICTING AN OPEN, PROGRESSIVE SHORTWAVE TROUGH MOVING OUT OF
CENTRAL CANADA INTO THE UPPER MIDWEST. WHILE THERE IS STRONG
CONSENSUS IN THIS SYNOPTIC WAVE, THERE ARE DIFFERING SCENARIOS
IN ITS PROGRESSION AND STRENGTH. UNCERTAINTY IN THE UPPER
PATTERN THEN DEGRADES AFTER FRIDAY'S SHORTWAVE PASSAGE WITH
EITHER UPPER RIDGING OUT OF THE WEST BECOMING THE DOMINATE
INFLUENCING MECHANISM FOR OUR WEATHER, OR UPPER TROUGHING OVER
THE GREAT LAKES. BOTH WOULD STILL FAVOR AVERAGE TEMPERATURES FOR
OUR AREA, HOWEVER.
..STRONG WINDS TODAY AND TONIGHT
STRONG SURFACE PRESSURE GRADIENT OVER OUR AREA AND MIXING OF LOW
LEVEL WINDS IN THE 40-50 KT RANGE IS CONTRIBUTING TO SUSTAINED
WINDS 25-35 MPH WITH GUSTS UP TO 50 MPH IN EASTERN NORTH DAKOTA
INTO PORTIONS OF ADJACENT NORTHWEST AND WEST-CENTRAL MINNESOTA.
SOUTHEASTERLY DIRECTION OF WINDS IS FAVORING STRONGEST WINDS IN
THE SOUTHERN VALLEY WITH THE HELP OF DOWNSLOPING WITHIN THE
SOUTHERN VALLEY, AS WELL AS LOCALLY BETTER MIXING FROM DAYTIME
CLEARING. THIS WILL CONTINUE ADVISORY-CRITERIA WINDS THROUGH THE
AFTERNOON INTO THE EVENING.
AFTER SUNSET, DAYTIME HEATING CEASES, ALTHOUGH THE PRESSURE
GRADIENT REMAINS TIGHTENED OVER OUR AREA, ALONG WITH SOME
CONTINUED MIXING WITH THE HELP OF EITHER DOWNSLOPING/TERRAIN
INFLUENCES AS WELL AS TRANSFERRED WINDS FROM ALOFT WITH THE HELP
OF CONVECTION/WEAK THUNDERSTORMS TONIGHT. STILL THINKING WINDS
WILL REMAIN NEAR OR AT ADVISORY-CRITERIA AFTER SUNSET UNTIL
AROUND MIDNIGHT. WINDS ALOFT INCREASE OVER 50 KT TONIGHT, WHICH
INTRODUCES SOME UNCERTAINTY IN TAPPING INTO THESE NEAR WARNING-
TYPE CRITERIA. HOWEVER, THE CHANCE IN SEEING WARNING-CRITERIA
WINDS IS LOW, AT AROUND 10% BETWEEN 7PM - 1AM.
..SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY
LIFT AND STRONG MOISTURE TRANSPORT INTO OUR AREA GIVES HIGH
CONFIDENCE IN WIDESPREAD SHOWERS INTO EASTERN ND AND WEST-
CENTRAL AND NORTHWEST MN. WEAK INSTABILITY FEEDING INTO THIS
MOISTURE TRANSPORT ALLOWS THE CHANCE FOR WEAK THUNDERSTORMS
TONIGHT INTO TUESDAY.
TUESDAY MIDDAY, SOME HIGH RESOLUTION GUIDANCE DOES BRING A
SURFACE FRONT THROUGH INTO OUR AREA, COUPLED WITH RELATIVELY
WARMER/MORE MOIST AIR MASS. WITH FORCING ALOFT AND AT THE
SURFACE FROM CONVERGENCE AND FRONTAL LIFT AMID SURFACE CAPE
VALUES 100-500 J/KG, CLUSTERS OF SEMI-DISCRETE AND/OR A LINE OF
THUNDERSTORMS ARE EXPECTED. IN THIS SAME AREA, LOW LEVEL WINDS
VEER WITH HEIGHT, WITH GOOD VENTILATION ALOFT. SHOULD
THUNDERSTORMS REMAIN SEMI-DISCRETE AND ATTACH THEMSELVES ON THE
BOUNDARY, FUNNELS AND/OR A COUPLE OF QUICK TORNADOES CANNOT BE
RULED OUT. THIS CONDITIONAL CHANCE IS LOW, LESS THAN 10%, BUT
STILL EXISTS AND WOULD INCREASE IF MORE DISCRETE MODE AND/OR
GREATER INSTABILITY BECOMES MORE FAVORED. THE WINDOW OF
OPPORTUNITY FOR SUCH POTENTIAL EXISTS BETWEEN 11AM TO 4PM.
OTHERWISE, ACCUMULATED PRECIPITATION IS FORECAST TO RANGE IN
THE 0.20 - 0.75 INCHES, WITH LOCALLY HIGHER AMOUNTS UP TO 1.5
INCHES IN AREAS THAT SEE NUMEROUS ROUNDS OF SHOWERS AND
THUNDERSTORMS.
AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
ISSUED AT 1142 PM CDT MON MAY 6 2024
KEPT WITH THE SAME IDEAS FROM THE 00Z SET OF TAFS. STILL TRYING
NOT TO CHASE THE SHOWERS/STORMS WITH TOO MANY TEMPO GROUPS.
SHOWERY ACTIVITY TENDS TO HAVE ON AND OFF PERIODS, BUT THINK
FOR AT LEAST MOST OF THE FIRST 6 HOURS OF THE TAF PERIOD THERE
WILL BE MORE "ON" PERIODS. THEREFORE, WILL JUST MENTION -SHRA
IN THE PREDOMINANT GROUP AND LEAVE THE TEMPO'S OFF. THERE HAS
BEEN SOME LIGHTNING, BUT OVERALL THINK THAT WILL STAY ISOLATED
ENOUGH THAT WILL LEAVE THAT MENTION OUT TOO. PUT THE LLWS IN THE
TAFS WITH THE 00Z ISSUANCE, AND WILL KEEP THAT THROUGH MOST OF
THE NIGHT AS WELL. WIND SPEEDS HAVE BEEN VERY CHALLENGING, AS
SOME STATIONS ARE STILL SEEING BREEZY WINDS, WHILE OTHERS HAVE
LOST THEIR GUSTS. THINK THOSE THAT HAVE LOST GUSTS WILL GET THEM
BACK AGAIN, AND THAT IS REALLY NOT WORTH CHASING TOO MUCH
EITHER. BEYOND THAT, HAVE GONE WITH VFR CONDITIONS ARRIVING
AGAIN BY MID TO LATE TUESDAY MORNING, BUT DON'T HAVE MUCH
CONFIDENCE THAT IT WILL SCATTER OUT. IF IT DOES SCATTER OUT,
SOME INSTABILITY COULD FORM AGAIN SOUTH OF THE HIGHWAY 2
CORRIDOR, LEADING TO ISOLATED SHOWER/STORM DEVELOPMENT AGAIN.
THE BREEZY CONDITIONS WILL RETURN BY MID TUESDAY MORNING,
BEFORE THEY DECREASE AGAIN BY LATE AFTERNOON AND EARLY EVENING
(ALTHOUGH MUCH LESS THAN TODAY).
FGF WATCHES/WARNINGS/ADVISORIES
ND...NONE.
MN...NONE.
UPDATE...GODON
DISCUSSION...CJ
AVIATION...GODON
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