699
FXUS63 KMQT 210538
AFDMQT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1238 AM EST THU NOV 21 2024
KEY MESSAGES
- LIGHT WET SNOW ACCUMULATIONS POSSIBLE TONIGHT, MAINLY IN THE
HIGHER TERRAIN WEST OF US-41 AND SOUTH OF THE KEWEENAW.
- NORTHERLY GALES 35 TO 40 KNOTS WITH A FEW GUSTS TO 45 KNOTS
POSSIBLE ACROSS LAKE SUPERIOR.
- WIDESPREAD 25 TO 35 MPH NORTHERLY WINDS WILL BE POSSIBLE
ACROSS UPPER MICHIGAN THURSDAY. HIGHER WINDS TO 45 MPH WILL
BE POSSIBLE IN THE KEWEENAW PENINSULA AND NEAR THE IMMEDIATE
LAKESHORES OF MARQUETTE AND ALGER COUNTIES.
UPDATE
ISSUED AT 852 PM EST WED NOV 20 2024
THE FORECAST REMAINS ON TRACK TONIGHT. LIGHT RAIN SHOWERS ARE
SPREADING WESTWARD THROUGH THE UP TONIGHT, WITH PERIODS OF BRIGHT-
BANDING UNSURPRISING GIVEN FREEZING LEVELS ONLY AT AROUND 1000FT. SOME
SPOTS, PARTICULARLY IN THE HIGHER TERRAIN, ARE ALREADY SEEING SNOW
MIX IN. MINOR ADJUSTMENTS WITH THIS FORECAST UPDATE HAVE BEEN TO
BUMP UP WINDS SLIGHTLY OVER THE WESTERN HALF OF THE UP INTO EARLY
THURSDAY. WE MAY FLIRT WITH WIND ADVISORY CRITERIA ACROSS THE
KEWEENAW AND CLOSER TO SUPERIOR IN MARQUETTE COUNTY, BUT WITH SOME
LINGERING UNCERTAINTY AS THE HIGHEST MODEL GUIDANCE CLOSER TO 45MPH
REMAINS AN OUTLIER, WILL HOLD OFF ON HEADLINES.
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 407 PM EST WED NOV 20 2024
CURRENT RAP ANALYSIS SHOWS AN ELONGATED MID LEVEL CLOSED LOW OVER MN
AND WI WITH A RIDGE OVER THE ROCKIES. AS A SHORTWAVE ROTATES AROUND
THE MID LEVEL CLOSED LOW THIS EVENING THROUGH TONIGHT OVER MI, A SFC
LOW DEEPENS OVER THE LOWER GREAT LAKES. THE WEAKENING SFC LOW PHASES
WITH THE DEEPENING LOW AS IT ROTATES FROM LAKE HURON TO EASTERN
UPPER MI. STRONG Q-VECTOR CONVERGENCE OVER THE EAST HAS ALLOWED FOR
SHOWERS TO EXPAND OVER THE EASTERN UP AS VISIBLE ON RADAR IMAGERY
AND AVAILABLE WEBCAMS. REFLECTIVITY RETURNS HAVE PERIODICALLY LIFTED
OVER PORTIONS OF THE CENTRAL UPPER MI AND THE KEWEENAW ALREADY
TODAY, BUT AN ANTECEDENT DRY AIRMASS HIGHLIGHTED BY DEWPOINT
DEPRESSIONS OF UP TO 10-15F HAS REALLY WORKED AGAINST PRECIP
EXPANDING WESTWARD. WHILE SOME ISOLATED RAIN AND SNOW SHOWERS ARE
POSSIBLE IN THE WEST HALF AHEAD OF 7 PM EST, BETTER CHANCES HOLD OFF
UNTIL LATER THIS EVENING THROUGH TONIGHT. AT THAT POINT, A COLDER
AIRMASS WILL HAVE MOVED OVER THE WEST, AIDING IN A TRANSITION OVER
TO SNOW SHOWERS. MINIMUM TEMPS IN THE LOW 30S TO LOW 40S ARE
EXPECTED EARLY ON TONIGHT AS WAA STRENGTHENS AFTER MIDNIGHT. THAT
SAID, SOME LIGHT WET SNOW ACCUMULATIONS ARE POSSIBLE TONIGHT, MAINLY
WEST OF US-41 AND SOUTH OF THE KEWEENAW. HIGHEST SNOW TOTALS UP TO
1-3 INCHES ARE POSSIBLE IN THE HIGH TERRAIN OF BARAGA COUNTY. OPTED
TO COVER POTENTIAL HAZARDOUS TRAVEL CONDITIONS OVERNIGHT WITH A SPS
AS A TRANSITION OVER TO RAIN SHOWERS BY THURSDAY MORNING WILL
LIKELY WORK AGAINST ANY SNOW ACCUMULATIONS.
OTHERWISE, THE STRENGTHENING LOW APPROACHING FROM THE EAST WILL
RESULT IN INCREASING NORTHWEST WINDS TONIGHT. GUSTS ARE EXPECTED TO
APPROACH 20-30 MPH (UP TO 35 MPH IN THE KEWEENAW) BY THURSDAY
MORNING.
LONG TERM /THURSDAY THROUGH WEDNESDAY/
ISSUED AT 429 PM EST WED NOV 20 2024
HEADING INTO THE LATE WEEK, A CLOSED 500MB LOW OVER THE UPPER
MIDWEST DESCENDS SOUTHEAST ACROSS THE GREAT LAKES INTO THE EASTERN
SEABOARD. BY THURSDAY MORNING, THE ATTENDANT SURFACE PRESSURE
REFLECTION WILL HAVE ROUNDED COUNTERCLOCKWISE ABOVE THE MITTEN OF
MICHIGAN AND DEEPENED TO NEAR 993MB JUST WEST OF THE STRAITS OF
MACKINAC. GUIDANCE IS IN GOOD AGREEMENT ON A PERIOD OF ENHANCED
NORTHERLY FLOW ACROSS LAKE SUPERIOR FOLLOWING STRONG PRESSURE RISES
WHERE GUSTS 35-40 KNOTS ARE LIKELY (80-100% CHANCE) THURSDAY MORNING
INTO THE EVENING. AT THE SAME TIME, ONGOING RAIN/SNOW MIX WILL BE
TRANSITIONING TO ALL RAIN AS THE LOW PRESSURE ROTATES DOWN LAKE
MICHIGAN THURSDAY. WHILE NORTHEAST FLOW OVER LAKE SUPERIOR TYPICALLY
RESULTS IN COLD AIR ADVECTION AND LAKE EFFECT SNOW, THE WOUND-UP
TROWAL SENDS IN LOW-LEVEL TEMPS JUST ABOVE FREEZING. RAIN AMOUNTS
THURSDAY WILL BE MAXIMIZED IN THE EAST AND CENTRAL UP WHERE
NORTHERLY UPSLOPE COULD AID IN SOME LOCALS ACCUMULATING OVER AN
INCH. AS THE SURFACE LOW PRESSURE AND UPPER LOW CONTINUE INTO THE
EASTERN SEABOARD, RIDGING NUDGES IN FROM THE WEST INTO THE UPPER
GREAT LAKES FRIDAY, FILTERING IN DRIER AIR ALOFT. SOME LIGHT PRECIP
AND DRIZZLE WILL LINGER FRIDAY WITH NORTHERLY UPSLOPE FLOW.
A SHORTWAVE DIVES SOUTHEAST OVER NORTHERN ONTARIO SATURDAY, SENDING
A SHOT OF COLDER 850MB TEMPS AROUND -8 TO -10C ACROSS LAKE SUPERIOR.
SUFFICIENT LAKE INDUCED INSTABILITY WILL BE PRESENT FOR LAKE EFFECT
CLOUDS AND MAYBE SOME LIGHT RAIN/SNOW SHOWERS OVER THE EAST UP,
HOWEVER, ANY SHOWERS WILL BE FIGHTING A DRY SURFACE LAYER, SO LITTLE
TO NO ACCUMULATION IS EXPECTED.
ACTIVE WEATHER CONTINUES BEYOND THE WEEKEND WITH A DEEPENING TROUGH
OVER THE CENTRAL US LATE MONDAY INTO TUESDAY, HOWEVER, THE CURRENT
DETERMINISTIC MODEL SUITE IS STILL FIGURING OUT THE GENERAL
TIMING/LOCATION OF A SURFACE LOW TRAVERSING EASTWARD ACROSS THE OHIO
RIVER VALLEY AND DEPTH OF COLD AIR DESCENDING FROM ONTARIO. THIS
WILL BE A TARGET OF OPPORTUNITY FOR FUTURE FORECAST PACKAGES AS LAKE
EFFECT SNOW AND COLDER TEMPS COULD IMPACT THANKSGIVING HOLIDAY
TRAVEL.
AVIATION /06Z TAFS THROUGH 06Z FRIDAY/
ISSUED AT 1236 AM EST THU NOV 21 2024
AN AREA OF LOW PRESSURE IS CURRENTLY PUSHING FROM EAST TO WEST
ACROSS THE UP, BRINGING WITH IT A MESSY MIX OF PRECIPITATION. SNOW
WILL FALL EARLY IN THE TAF PERIOD BEFORE TRANSITIONING TO A MIX OF
RAIN AND SNOW AND FINALLY ALL RAIN. THE TRANSITION TO A RAIN/SNOW
MIX WITH HAPPEN AT SAW BY 08Z AND IWD BY 09Z. THE TRANSITION TO RAIN
WILL HAPPEN AT SAW BY 10Z AND AT IWD BY 12Z. RAIN WILL BE THE
PREDOMINANT PRECIPITATION TYPE AT CMX FOR THE ENTIRE TAF PERIOD. IFR
CONDITIONS WILL DEVELOP BY 09Z ACROSS THE AREA AND PERSIST ACROSS
ALL TERMINALS THROUGH THE TAF PERIOD. THERE IS A 20 PERCENT CHANCE
LIFR CONDITIONS WILL DEVELOP AT SAW DURING THE DAY ON THURSDAY.
OTHERWISE, NORTHWEST WINDS INCREASE EARLY THIS MORNING, GUSTING UP
TO 25-30 KTS AT IWD AND UP TO ~35 KT AT SAW/CMX.
MARINE
ISSUED AT 429 PM EST WED NOV 20 2024
DEEPENING SURFACE LOW PRESSURE ROUNDING LOWER MICHIGAN AND
DESCENDING DOWN THE AXIS OF LAKE MICHIGAN LATE TONIGHT THROUGH
THURSDAY WILL BRING MARINE HAZARDS TO LAKE SUPERIOR THROUGH THURSDAY
EVENING. NORTHERLY WINDS OVER CENTRAL AND EAST LAKE SUPERIOR PICK
UP LATE TONIGHT, INCREASING ABOVE 25 KNOTS AROUND 7PM EST, AND 35
KNOTS JUST AFTER MIDNIGHT. BY THURSDAY MORNING, THE PRESSURE
GRADIENT BE COMES MAXIMIZED ACROSS THE LAKE AND GUSTS 35-40 KNOTS
EXPAND ACROSS MUCH OF THE LAKE, ESPECIALLY CLOSEST TO THE KEWEENAW.
A FEW STRAY GUSTS TO 45 KNOTS ARE POSSIBLE (30%), PARTICULARLY
BETWEEN 5-10AM EST. AS THE SURFACE LOW CONTINUES SOUTH AND EAST
THURSDAY EVENING, WINDS BEGIN TO SLACKEN BELOW GALE CRITERIA BY AT
LEAST 7PM EST WHILE REMAINING OUT OF THE NORTH. INTO THE WEEKEND,
NORTHEAST WINDS REMAIN ELEVATED ON FRIDAY AROUND 25 KNOTS WITH A FEW
GUSTS TO 30 KNOTS, FURTHER LESSENING BELOW 20 KNOTS SATURDAY. WINDS
REMAIN LIGHT THROUGH THE EARLY PORTIONS OF NEXT WEEK, BUT COULD GUST
TO 25 KNOTS ON TUESDAY.
MQT WATCHES/WARNINGS/ADVISORIES
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 5 AM EST /4 AM CST/ EARLY THIS MORNING TO 2
PM EST /1 PM CST/ THIS AFTERNOON FOR LSZ162-263.
GALE WARNING FROM 6 AM EST /5 AM CST/ THIS MORNING TO 3 PM EST
/2 PM CST/ THIS AFTERNOON FOR LSZ241>243-246-247.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ244-245.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ248>250-265-
266.
GALE WARNING UNTIL 3 PM EST THIS AFTERNOON FOR LSZ264.
GALE WARNING FROM 5 AM TO 10 AM EST THIS MORNING FOR LSZ267.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LMZ221-248-250.
UPDATE...LC
SHORT TERM...JABLONSKI
LONG TERM...BW
AVIATION...RM
MARINE...BW
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