394
FXUS63 KMQT 240303
AFDMQT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1103 PM EDT WED JUL 23 2025
KEY MESSAGES
- SHOWERS AND THUNDERSTORMS ARE EXPECTED TONIGHT INTO THURSDAY.
- ADDITIONAL NON-SEVERE THUNDERSTORMS ARE POSSIBLE THURSDAY, ENDING
WEST TO EAST.
UPDATE
ISSUED AT 1102 PM EDT WED JUL 23 2025
EARLIER SHOWERS AND THUNDERSTORMS HAVE LARGELY EXITED THE FORECAST
AREA SAVE FOR THE TAIL END MOVING THROUGH LUCE COUNTY. CURRENT
GUIDANCE HANDLING UPSTREAM CONVECTION PRESENT MIXED RESULTS, BUT
RADAR/SATELLITE OBSERVATIONS INDICATE A WEAKENING TREND AS THEY
SLOWLY LIFTED NORTHEAST. OVER THE NEXT COUPLE HOURS, THE FRONTAL
BOUNDARY IN WHICH THESE ARE FOCUSING ALONG WILL SHIFT EASTWARD,
WHICH WILL HELP THESE SHOWERS/STORMS LARGELY AVOID OUR FORECAST
AREA. THE AREA WITH THE GREATEST POTENTIAL OF ADDITIONAL RAIN
OVERNIGHT WILL BE SOUTHERN MENOMINEE COUNTY DUE TO THEIR PROXIMITY
TO THE ADVANCING CONVECTION. WITH THIS IN MIND, OPTED TO CANCEL THE
FLOOD WATCH.
SHORT TERM /THROUGH THURSDAY/
ISSUED AT 307 PM EDT WED JUL 23 2025
THE UPPER LEVEL PATTERN THIS AFTERNOON SHOWS TROUGHING OVER MUCH OF
CANADA WITH A SHORTWAVE TROUGH APPROACHING THE NORTHERN PLAINS. AN
UPPER LEVEL HIGH PRESSURE WAS OVER THE SOUTHEASTERN U.S WITH THE
RIDGE AXIS EXTENDING NORTH INTO THE EASTERN GREAT LAKES.
MULTIPLE SMALLER SCALE SHORTWAVES WERE MOVING THROUGH THE UPPER
MIDWEST AND APPROACHING UPPER GREAT LAKES. SHOWERS AND
THUNDERSTORMS HAD DEVELOPED OVER CENTRAL AND NORTHERN MN AND
NORTHWEST WI. SOME OF THESE WERE STARTING TO PUSH INTO THE FAR
WEST AND SOUTH.
SOUTHERLY FLOW WAS TRANSPORTING ABUNDANT MOISTURE INTO THE AREA
WITH PRECIPITABLE WATER VALUES APPROACHING 2 INCHES. OBSERVED
SOUNDINGS THIS MORNING AT MPX AND GRB BOTH SHOWED PW VALUES OF
1.87 AND 1.84 RESPECTIVELY. THIS IS WELL ABOVE THE 90TH
PERCENTILE OF CLIMATOLOGY FOR LATE JULY.
THE AFOREMENTIONED SHORTWAVES WILL MOVE THOUGH THE AREA TONIGHT
WHILE A COLD FRONT PUSHES SOUTHEAST THROUGH THE AREA. THIS WILL
RESULT IN MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS. GUIDANCE
FROM THE CAMS IS ALL OVER THE PLACE WITH TIMING AND LOCATION OF
CONVECTION. ONE THING THAT THEY DO AGREE ON IS A CONVECTIVE
MODE THAT IS MOSTLY LINEAR GIVEN THE STORM MOTION AND SHEAR
RELATIVELY PARALLEL TO THE BOUNDARY. SHEAR WILL INCREASE THROUGH
THE EVENING WHICH SHOULD BE ABLE TO SUPPORT MORE ORGANIZED
CONVECTION. HEAVY RAINFALL AND DAMAGING WINDS WILL BE THE MAIN
THREAT FROM THE STORMS. A DEEP WARM AIRMASS WILL LIMIT THE HAIL
POTENTIAL. A STRENGTHENING LOW LEVEL JET WILL BRING INCREASING
LOW LEVEL WIND SHEAR THIS EVENING. LOW LEVEL WIND SHEAR AND
INSTABILITY LOOK SUFFICIENT FOR AN ISOLATED TORNADO THREAT,
MAINLY WITH ANY BOWING SEGMENTS THAT FORM THIS EVENING.
EXCESSIVE RAINFALL WILL CONTINUE TO BE A CONCERN WITH TORRENTIAL
DOWNPOURS POSSIBLE WITH ANY STORMS, ESPECIALLY IN AREAS WHERE
THUNDERSTORMS TRAIN ALONG THE FRONT. THERE IS A SLIGHT RISK FOR
EXCESSIVE RAINFALL ACROSS THE ENTIRE U.P THIS EVENING AND
OVERNIGHT. OVER THE WEST SOILS ARE ALREADY SATURATED FROM STORMS
LAST NIGHT WHERE 1"+ AND UPWARDS OF 3" OF RAINFALL OCCURRED IN
PORTIONS OF ONTONAGON AND HOUGHTON COUNTIES. BASED ON THE
CURRENT SOIL CONDITIONS AND EXPECTED ADDITIONAL RAINFALL OF 1"
TO POTENTIALLY OVER 2" A FLOOD WATCH HAS BEEN ISSUED OVER THE
WEST FOR THIS AFTERNOON THROUGH TONIGHT FOR THE FLASH FLOOD
THREAT.
LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/
ISSUED AT 307 PM EDT WED JUL 23 2025
SHORTWAVE RIDGING WILL BUILD INTO THE REGION ON FRIDAY WITH THE
UPPER LEVEL HIGH REMAINING OVER THE SOUTHEASTERN U.S AND ANOTHER
TROUGH PUSHING INTO WESTERN CANADA. THIS WILL RESULT IN A DRY
DAY TO END THE WORKWEEK. THEREAFTER THE UPPER LEVEL HIGH
PRESSURE OVER THE SOUTHEAST BEGINS TO RETROGRADE TO THE WEST
WHILE TROUGHING CONTINUES TO AFFECT MUCH OF CANADA. THE UPPER
GREAT LAKES LOOKS LIKE IT WILL BE IN A FAVORABLE LOCATION FOR
SHORTWAVES RUNNING AROUND THE RIDGE WITH WEST-NORTHWEST FLOW
ALOFT. THIS WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORM
BACK INTO THE FORECAST THIS WEEKEND. TEMPERATURES WILL RUN
ABOVE AVERAGE THIS WEEKEND WITH CONTINUED HUMID CONDITIONS.
AVIATION /00Z TAFS THROUGH 00Z FRIDAY/
ISSUED AT 1055 PM EDT WED JUL 23 2025
RAIN HAS SINCE ENDED AT TERMINALS IN UPPER MICHIGAN AND TRENDS
INDICATE THAT UPSTREAM SHOWERS AND STORMS WILL LARGELY AVOID
KIWD/KCMX/KSAW. ABUNDANT MOISTURE IN THE LOW LEVELS IS STILL
EXPECTED TO RESULT IN FLIGHT RESTRICTIONS TONIGHT INTO THURSDAY
MORNING. IN GENERAL LIFR AND IFR CONDITIONS ARE EXPECTED BEFORE
IMPROVING TO MVFR THURSDAY MORNING. AT KSAW, MVFR CONDITIONS
OVERNIGHT BEFORE FALLING TO IFR AND LIFR BY MORNING. ALL SITES LOOK
TO IMPROVE TO VFR BY THURSDAY AFTERNOON.
MARINE
ISSUED AT 307 PM EDT WED JUL 23 2025
WINDS GENERALLY OUT OF THE SOUTH MAY CONTINUE TO GUST TO AROUND
20KTS IN THE EASTERN HALF OF THE LAKE THE REST OF TODAY AND INTO THE
FIRST HALF OF THE NIGHT WITH LOW PRESSURE TROUGHING OVER THE GREAT
LAKES. ADDITIONAL ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED
ACROSS THE LAKE THIS EVENING THROUGH THURSDAY. SOME THE STORMS MAY
BE STRONG TO SEVERE, BRINGING FREQUENT LIGHTNING, ERRATIC/DAMAGING
WINDS (UP TO 30 PERCENT CHANCE), AND A WATERSPOUT CANNOT BE RULED
OUT (ABOUT A 2 PERCENT CHANCE). AFTER TONIGHT, WINDS FALL BACK
ACROSS THE LAKE AND REMAIN BELOW 20KTS THROUGH AT LEAST THE
REMAINDER OF THIS WEEK.
MQT WATCHES/WARNINGS/ADVISORIES
UPPER MICHIGAN...
FLOOD WATCH FROM 4 AM EDT /3 AM CDT/ TO 5 AM EDT /4 AM CDT/
THURSDAY FOR MIZ001>004-009-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
UPDATE...JTP
SHORT TERM...NL
LONG TERM...NL/TDUD
AVIATION...JTP
MARINE...LC
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