200
FXUS63 KMQT 201954
AFDMQT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
254 PM EST FRI DEC 20 2024
KEY MESSAGES
- LIGHT TO MODERATE LAKE EFFECT SNOWFALL CONTINUES INTO TONIGHT,
SHIFTING TO THE NORTH WIND SNOW BELTS BY SATURDAY MORNING.
BEST ACCUMULATIONS EXPECTED OVER NORTH CENTRAL UPPER MI LATE
TONIGHT/SATURDAY MORNING.
- CLIPPER MOVING THROUGH THE GREAT LAKES COULD BRING A
WIDESPREAD SNOW SUNDAY NIGHT INTO MONDAY.
- DRIER AND WARMER CONDITIONS EXPECTED BEHIND THE EARLY WEEK
SYSTEM FOR CHRISTMAS EVE AND CHRISTMAS DAY.
SHORT TERM /THROUGH THIS AFTERNOON/
ISSUED AT 332 AM EST FRI DEC 20 2024
RAP ANALYSIS SHOWS A 1015MB LOW OVER THE CHICAGO AREA WITH 500MB
TROUGHING PUSHING OVER THE UPPER GREAT LAKES. LIGHT SNOW SHOWERS
CONTINUE TO FALL ACROSS THE UP, WITH KMQT RADAR RETURNS SHOWING A
STRONGER BAND NEARLY PERPENDICULAR TO THE MARQUETTE COUNTY SHORELINE
WITH AN EMBEDDED MESOLOW ABOUT 30 MILES NORTHWEST OF PICTURED ROCKS
NATIONAL LAKESHORE. KDLH RADAR ALSO SHOWS A DOMINANT BAND THAT JUST
PASSED OVER THE BAYFIELD PENINSULA HEADED FOR THE IRONWOOD AREA
THROUGH THE EARLY MORNING HOURS. OTHERWISE, WITH REDUCTION IN
SNOW SHOWER STRENGTH OUTSIDE OF THOSE BANDS, WILL ELECT TO END
ALL REMAINING WINTER WEATHER ADVISORIES AT 12Z. WHILE SNOWFALL
RATES OF NEAR AN INCH/HR ARE EXPECTED WITH THE BAND OVER
BARAGA/MARQUETTE/ALGER COUNTY THIS MORNING, THE BAND WILL NOT
BE STAYING IN ONE SPOT TO ACCUMULATE SNOWFALL FOR A SIGNIFICANT
ENOUGH PERIOD OF TIME TO WARRANT A WINTER WEATHER ADVISORY FOR
BARAGA/MARQUETTE/ALGER COUNTIES, THOUGH AN SPS TO LOOKOUT FOR
RAPIDLY CHANGING ROAD CONDITIONS FOR THE MORNING COMMUTE HAS
BEEN ISSUED.
AS SNOW SHOWERS BECOME LIMITED TO THE KEWEENAW PENINSULA AND THE
EAST OF US-41 FROM MARQUETTE TO ESCANABA THROUGHOUT TODAY BEHIND THE
TROUGH ALOFT, TEMPERATURES WILL NOT RECOVER MUCH FROM THE MORNING,
WITH HIGHS ONLY EXPECTED TO BE IN THE 20S AFTER MORNING LOWS NEAR
20. THE NAM SHOWS 850MB TEMPERATURES OVER LAKE SUPERIOR FALLING
TO NEGATIVE 20 C BY 00Z SATURDAY, PLENTY SUPPORTIVE FOR POST-
TROUGH LAKE EFFECT BANDS OUT OF THE NORTH AND NORTHWEST.
CYCLONIC SURFACE FLOW OVER THE EAST HALF SHOULD FOCUS BANDS
AROUND THE MUNISING TO GRAND MARAIS AREA THIS AFTERNOON TO EVENING
WITH A LAKE NIPIGON CONNECTION, PROMPTING THE HREF TO SHOW
6-HOURLY PROBABILITIES OF 0.05"+ OF QPF OF 50+ OVER ALGER
COUNTY, AND WITH A SATURATED DGZ, SLRS OF NEAR 20:1 SHOULD ALLOW
FOR AN ADDITIONAL INCH OR TWO TO FALL OVER ALGER COUNTY WITH
SOME POTENTIAL (20-40%) FOR SOME SIMILAR SNOWFALL FOR NORTHERN
SCHOOLCRAFT COUNTY AND LUCE COUNTY AS WELL.
LONG TERM /SATURDAY THROUGH THURSDAY/
ISSUED AT 254 PM EST FRI DEC 20 2024
LAKE EFFECT SNOW SHOWERS OFF OF LAKE SUPERIOR WILL TAPER OFF
SATURDAY AS SURFACE HIGH PRESSES INTO WISCONSIN AND DRY AIR AND
SUBSIDENCE SUPPORT DRIER CONDITIONS. GUIDANCE SUGGESTS THAT LAKE
EFFECT SHOULD BE DIMINISHED ACROSS THE FORECAST AREA BY SATURDAY
EVENING. BEFORE THEN THOUGH, ADDITIONAL SNOWFALL AMOUNTS COULD CLIMB
ANOTHER INCH OR SO, MAINLY FROM MARQUETTE INTO WESTERN ALGER.
SOUTHERLY FLOW WILL SETTLE IN SATURDAY NIGHT. ITS POSSIBLE THIS
COULD SUPPORT LIGHT LAKE EFFECT SNOW OFF OF LAKE MICHIGAN INTO
EASTERN DELTA, SCHOOLCRAFT, AND LUCE COUNTIES SUNDAY, PERHAPS
YIELDING AN INCH OR TWO OF SNOW.
BROAD MID-UPPER LEVEL RIDGE TO TROUGH PATTERN STRETCHING ACROSS
CONUS AND CANADA THIS WEEKEND WILL GRADUALLY BREAK DOWN AS A
SHORTWAVE DIGS SOUTHEAST WITHIN THE NORTHWEST FLOW OVER THE WESTERN
PLAINS. AS THIS CLIPPER LOW PRESSES ACROSS THE NORTHERN PLAINS
SUNDAY NIGHT, A SURFACE LOW WILL DEVELOP AND PRESS NORTHEAST INTO
MINNESOTA. BY EARLY MONDAY, GENERAL CONSENSUS AMONG THE VARIOUS
DETERMINISTIC PACKAGES SUGGESTS THE NOW VERTICALLY STACKED FEATURE
WILL PRESS EASTWARD TO NEAR MENOMINEE DURING THE DAY AND THEN
EASTWARD OVERNIGHT INTO TUESDAY. THERE ARE SOME OUTLIERS THOUGH,
NAMELY THE NAM, WHICH BRINGS THE SYSTEM CLOSE TO THUNDER BAY. WHILE
THERE IS SOME SUPPORT FROM A COUPLE ENSEMBLE MEMBERS OF THE EC,
GEFS, AND GEPS, WILL TREAT THE NORTHERN SOLUTION AS AN OUTLIER IN
THIS FORECAST PACKAGE FOR THE TIME BEING. THE TRACK OF THE CONSENSUS
WOULD RESULT IN SYNOPTIC PRECIP SPREADING INTO THE AREA SUNDAY NIGHT
THROUGH MONDAY, FOLLOWED BY SOME LAKE EFFECT POTENTIAL INTO TUESDAY.
THE LAKE EFFECT IS LESS CERTAIN GIVEN THE SPEED AT WHICH RIDGING AND
WAA LIMITS SHOWER DEVELOPMENT. DESPITE THE AIRMASS ALOFT WARMING
WITH THE SYSTEM, IT STILL SHOULD BE COLD ENOUGH FOR PTYPE TO BE
PRIMARILY SNOW. SNOW WOULD BE WETTER THOUGH, WITH NBM SUGGESTING
SNOW RATIOS CLOSE TO 10:1. QPF IS LESS CERTAIN GIVEN THE POSSIBILITY
OF LAKE ENHANCEMENT OFF LAKE MICHIGAN INTO EASTERN UPPER MICHIGAN.
AT THIS POINT THOUGH, 0.10 TO 0.5 INCHES OF LIQUID (HIGHEST EAST -
LEAST WEST) LOOKS POSSIBLE, POTENTIALLY YIELDING 1 TO 5 INCHES OF
SNOW WITH ISOLATED HIGHER SPOTS BEING POSSIBLE (HIGHEST EAST - LEAST
WEST) SUNDAY NIGHT THROUGH MONDAY. THERE'S LESS SUPPORT WHEN
CONSIDERING SNOW AMOUNT PROBABILITIES FROM THE GEPS AND EC THOUGH.
THESE SUGGEST THE EAST HAS A 10-30% CHANCE OF SEEING AT LEAST 3
INCHES. THIS MAY HAVE SOMETHING TO DO WITH THE TRACK UNCERTAINTY OR
THE DIFFERENCES IN WARM AIR WHICH WILL IMPACT SNOW RATIOS. AT THIS
POINT THOUGH, WE'LL NEED TO CONTINUE MONITORING TRENDS THIS WEEKEND
TO BETTER IDENTIFY AMOUNTS AND POTENTIAL IMPACTS.
WARM AIR WILL PRESS INTO THE REGION AFTER THIS SYSTEM EXITS THE
REGION. DETERMINISTICS SUGGESTS 850MB TEMPS COULD WARM ABOVE 0C BY
CHRISTMAS MORNING, AND THEN LINGER BETWEEN +1 AND 3C THROUGH AT
LEAST THE FOLLOWING WEEKEND. THIS WARM AIRMASS WOULD SUPPORT
TEMPERATURES CLIMBING WELL INTO THE 30S WHILE OVERNIGHT LOWS DIP
ONLY INTO THE 20S. SOME LAKESHORE AREAS MAY EVEN STAY ABOVE FREEZING.
AVIATION /18Z TAFS THROUGH 18Z SATURDAY/
ISSUED AT 116 PM EST FRI DEC 20 2024
NORTHWEST WIND LAKE EFFECT SNOW SHOWERS CONTINUE TO STREAM OVER THE
UP THIS AFTERNOON AND ARE EXPECTED TO CONTINUE INTO SATURDAY AS THEY
TURN MORE NORTHERLY. THIS WILL MAINLY IMPACT SAW DURING THE 18Z TAF
PERIOD, HOWEVER SOME SNOW SHOWERS LOOK TO RETURN TO CMX THIS EVENING
AND TONIGHT. CLOUD BASES WILL PRIMARILY BE MVFR, BUT FEW/SCT CLOUD
DECKS ARE LIKELY BY LATE THIS AFTERNOON/EARLY EVENING AT IWD/CMX
BEFORE SKY COVERAGE INCREASES AND CIGS LOWER LATER TONIGHT.
DEPENDING ON WHERE A DOMINATING LAKE EFFECT BAND SETS UP LATE
TONIGHT, SOME IFR CONDITIONS ARE POSSIBLE AT SAW LATE. OPTED TO HOLD
OF ON IFR OR LOWER FLIGHT RESTRICTIONS WITH SOME UNCERTAINTY YET
REGARDING LAKE EFFECT BAND PLACEMENT.
MARINE
ISSUED AT 254 PM EST FRI DEC 20 2024
NORTHWEST 20 TO 30KT WINDS WILL GRADUALLY TAPER THIS EVENING,
EVENTUALLY FALLING BELOW 20KTS SATURDAY MORNING LAKE-WIDE. THESE
LIGHT WINDS WILL CONTINUE INTO EARLY SUNDAY MORNING, WHEN SOUTHERLY
WINDS BEGIN INCREASING AS THE NEXT SYSTEM APPROACHES THE GREAT
LAKES. THERE IS SOME UNCERTAINTY IN THE TRACK OF THE SYSTEM, BUT THE
CURRENT CONSENSUS AGREES ON PRESSURE GRADIENT INCREASING, WHICH WILL
WORK TO ENHANCE LOW LEVEL SOUTHERLY FLOW DURING THE DAY SUNDAY AND
SUNDAY NIGHT. 925MB WINDS AMONG THE GUIDANCE PACKAGES ARE SOUTHERLY
WINDS OF 30-40 KTS, WITH THE STRONGEST WINDS ACROSS EASTERLY LAKE
SUPERIOR. THERE SHOULD BE ENOUGH COLD AIR ALOFT AT THIS TIME TO MIX
STRONGER WINDS TO THE SURFACE, BUT HOW STRONG IS UNCERTAIN. GOING
FORECAST IS FOR WINDS TO INCREASE TO NEAR 30KTS, BUT CAN'T RULE OUT
SOME GALES. LATEST EC ENSEMBLE SYSTEM SUGGESTS GALE PROBABILITIES
BETWEEN 10 AND 40% ACROSS EASTERN LAKE SUPERIOR. MODEL SOUNDINGS
ALSO SUGGEST THIS COULD END UP BEING A DOWNSLOPING WIND EVENT NEAR
THE UPPER MICHIGAN LAKESHORES EAST OF MARQUETTE. SO THESE NEARSHORE
AREAS MAY NOT BE REMOVED FROM THE STRONGER WINDS EITHER.
WINDS WILL SETTLE WEST TO EAST SUNDAY NIGHT INTO MONDAY. A WARMER
THAN NORMAL AIRMASS WILL SETTLE OVER THE AREA AFTERWARDS. THIS LOOKS
TO HELP MAINTAIN LIGHT WINDS FOR A MAJORITY OF NEXT WEEK.
MQT WATCHES/WARNINGS/ADVISORIES
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
SHORT TERM...GS
LONG TERM...JTP
AVIATION...JABLONSKI
MARINE...JTP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page