450
FXUS63 KMQT 221950
AFDMQT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
250 PM EST SAT FEB 22 2025
KEY MESSAGES
- THE NEXT CHANCE FOR WIDESPREAD CHANCES OF PRECIPITATION OVER
30% IS SUNDAY NIGHT AHEAD OF A CLIPPER LOW PASSING MONDAY.
RAIN AND SNOW ARE EXPECTED WITH UP TO 15% CHANCES OF A LIGHT
GLAZE OF FREEZING RAIN ON MONDAY.
- LOOKING MILDER THIS WEEKEND INTO THE FIRST HALF OF NEXT WEEK
WITH PERIODS OF ABOVE FREEZING TEMPERATURES LIKELY. MODELS
THEN TREND TO NEAR OR BELOW NORMAL FOR THE END OF NEXT WEEK
(THURSDAY-FRIDAY).
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 249 PM EST SAT FEB 22 2025
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW NW MID-LEVEL FLOW INTO THE
GREAT LAKES THIS AFTN. A COUPLE OF SHORTWAVES EMBEDDED IN THIS FLOW
HAVE PRODUCED SOME AREAS OF -SN ACROSS UPPER MI TODAY, MAINLY ACROSS
WESTERN AND NORTHERN UPPER MI. CURRENT TEMPS RANGE THRU THE 20S TO
THE LWR 30S F.
SHORTWAVE CURRENTLY NW OF LAKE SUPERIOR WILL PASS ACROSS THE AREA
THIS EVENING. UNTIL PASSAGE, SOME AREAS OF -SN/FLURRIES WILL
CONTINUE. LAST OF THE -SN IS ABOUT TO DEPART THE KEWEENAW, AND IT
WILL EXIT THE EASTERN FCST BY MIDNIGHT, IF NOT SOONER. SFC TROF
DROPPING S ACROSS LAKE SUPERIOR TONIGHT WILL END UP OVER SOUTHERN
LAKE SUPERIOR OR JUST INTO NORTHERN UPPER MI. MIGHT BE SOME FLURRIES
ASSOCIATED WITH IT, BUT SINCE AIR MASS IS NOT COLD ENOUGH TO SUPPORT
LAKE EFFECT SHSN, DID NOT INCLUDE ANY MENTION OF PCPN WITH THE TROF.
EXPECT MIN TEMPS MOSTLY IN THE UPPER TEENS TO MID 20S F, BUT
TRADITIONAL INTERIOR COLD SPOTS MAY SLIP TO THE LOWER TEENS F.
LONG TERM /SUNDAY THROUGH FRIDAY/
ISSUED AT 452 AM EST SAT FEB 22 2025
POSITIVE 500MB HEIGHT ANOMALIES OVER MUCH OF THE CONUS WILL PERSIST
THROUGH SUNDAY AND THE FIRST HALF OF NEXT WEEK WITH A MILDER AIRMASS
OVER MUCH OF THAT AREA AS A RESULT. GENERALLY, THE FLOW PATTERN WILL
BE PRIMARILY NORTHWESTERLY WITH PERIODIC QUICK CLIPPER SHORTWAVE
PROVIDING THE SYNOPTIC SUPPORT FOR PRECIPITATION AND EVENTUALLY
SHOULD RESULT IN TEMPERATURES COOLING TO MORE NEAR-NORMAL
TEMPERATURES BY THE END OF THE WEEK. BEFORE THE RETURN TO NORMAL
TEMPERATURES, HIGH TEMPERATURES WILL CLIMB ABOVE FREEZING FOR MUCH
OF THE FIRST HALF OF THE WEEK INCLUDING MONDAY WHERE TEMPERATURES IN
THE MID-40S ARE EXPECTED IN THE SOUTH-CENTRAL (50+%). THIS MEANS
THAT WHAT PRECIPITATION DOES FALL WITH THE CLIPPERS COULD INCLUDE
PERIODS OF RAIN AS WELL AS SNOW. WHILE THERE IS A SLIGHT (~15%)
CHANCE OF FREEZING RAIN MONDAY, IMPACTS ARE NOT EXPECTED TO BE MUCH
AS ACCUMULATIONS ARE NOT EXPECTED TO EXCEED A LIGHT GLAZE. THIS
MILDER AIRMASS WILL ALSO PROVIDE A BREAK FROM LAKE EFFECT
PRECIPITATION UNTIL AT LEAST THURSDAY.
BEGINNING SUNDAY, A DRY DAY IS EXPECTED OVER THE MAINLAND OF THE UP.
THE EXCEPTION WILL BE ISLE ROYALE, WHERE THE HREF SHOWS A WINDOW OF
15-30% CHANCES OF SNOW OVER THE PARK IN THE AFTERNOON. WITH
TEMPERATURES CLIMBING TO NEAR FREEZING DURING THE DAY, SNOW RATIOS
WILL APPROACH 10:1, AND WITH THE MEAN HREF 6-HOURLY PRECIP RATES
AROUND 0.02 INCHES, THE ISLE WILL BE UNLIKELY TO SEE A HALF INCH OF
SNOW SUNDAY. OTHERWISE, THE UP WILL SEE A SLIGHT UPTICK IN SOUTHERLY
WINDS, THOUGH GUSTS OVER LAND SHOULD STILL REMAIN BELOW 20 MPH. THE
WARM SOUTHERLY FLOW WILL BRING HIGHS INTO THE MID-30S FOR MOST.
OVERNIGHT, A POTENT CLIPPER SHORTWAVE WILL SUPPORT A SURFACE LOW IN
THE UPPER 980S TO LOWER 990S MB PASSING THROUGH NORTHERN ONTARIO
OVERNIGHT INTO MONDAY, REACHING JAMES BAY IN THE EVENING HOURS OF
MONDAY. THE COLD FRONT WILL BRING PRECIPITATION TO THE UP, WITH THE
BEST TOTALS EXPECTED OVER THE NORTH AND EAST WITH THE LOWEST TOTALS
EXPECTED ALONG THE MI/WI STATE LINE. PRECIPITATION TYPE WILL BE A
FORECAST CHALLENGE WITH THIS SYSTEM AS THE LREF SHOWS A 20-30%
CHANCE OF FREEZING RAIN OVER THE CENTRAL UP MONDAY, THOUGH ONLY A
FEW SOUNDINGS SHOW A PARTICULARLY NOTABLE INVERSION, SO RAIN AND
SNOW ARE FORECAST TO BE THE PRIMARY PRECIPITATION TYPES. THE GENERAL
PATTERN WILL BE SNOW FORMING OVERNIGHT AHEAD OF THE FRONT ASSOCIATED
WITH THE WARM ADVECTION/ISENTROPIC ASCENT, BUT THAT SAME WARM
ADVECTION CAUSING TEMPERATURES TO CLIMB THROUGH THE MORNING AND
SWITCHING SNOW OVER TO RAIN. THE LREF SHOWS OVER 50% CHANCES OF 45+
DEGREE F TEMPERATURES IN THE SOUTH-CENTRAL BY 18Z. HOWEVER, THE
SWITCH TO COLD ADVECTION BEHIND THE FRONT THROUGH THE EVENING WILL
SUPPORT A SWITCHOVER BACK TO SNOW FOR SOME, THOUGH MINTS ONLY IN THE
UPPER 20S TO LOW 30S WILL MAKE IT CHALLENGING FOR MUCH FREEZING OF
ROAD SURFACES TO OCCUR, SO HAZARDOUS WEATHER REMAINS UNLIKELY.
AS THE NORTHWESTERLY PATTERN SUPPORTS QUITE A LARGE NUMBER OF LOW-
AMPLITUDE SHORTWAVES, THIS PATTERN LENDS ITSELF TO A RAPID INCREASE
IN ENSEMBLE SPREAD IN A SHORT PERIOD OF TIME. ENSEMBLES SHOW
CLUSTERS OF SOLUTIONS WITH A CLIPPER LOW OVER THE REGION VIRTUALLY
EVERY DAY FOR THE REMAINDER OF THE FORECAST, BUT ONLY RARELY DO
ENSEMBLE POPS EVER EXCEED 50%. WEDNESDAY LOOKS TO HAVE THE STRONGEST
SIGNAL FOR A LOW PRESSURE OF SOME SORT, BUT THE GEFS SHOWS LOW
PRESSURE CENTERS ALL THE WAY FROM ARKANSAS TO HUDSON BAY, SO
CONFIDENCE IN TRACK OF ANY SUCH FEATURE IS LOW. WHAT DOES BECOME
MORE CERTAIN IS THAT AFTER WEDNESDAY, TEMPERATURES BECOME MORE
LIKELY TO BE NEAR NORMAL FOR THIS TIME OF YEAR (HIGHS IN THE 20S,
LOWS NEAR 10) AND AS A RESULT, SNOW BECOMES THE MORE PREFERRED
PRECIPITATION TYPE BY THE END OF THE WEEK INSTEAD OF THE RAIN/SNOW
ALTERNATIONS OF THE EARLY WEEK. THE LATE WEEK COULD ALSO SEE A
RETURN TO LAKE EFFECT SNOW AS 850MB TEMPERATURES OVER LAKE SUPERIOR
BECOME 20% LIKELY TO FALL BELOW -13 C BY THURSDAY MORNING, 35%
LIKELY BY FRIDAY, AND 75% LIKELY NEXT WEEKEND.
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
ISSUED AT 1246 PM EST SAT FEB 22 2025
AREAS OF -SN WILL PASS ACROSS THE AREA OVER THE NEXT FEW HRS,
LEADING TO OCNL MVFR AT IWD/SAW AND MVFR/OCNL IFR AT CMX.
AFTERWARDS, EXPECT VFR TO PREVAIL AT ALL TERMINALS INTO THE EARLY
EVENING. MVFR CIGS WILL RETURN AT CMX MID EVENING AND AT SAW LATE
TONIGHT AS A SFC TROF NEARS. SW WINDS TO AROUND 10KT AT IWD/SAW AND
WESTERLY 10-15KT AT CMX THIS AFTN WILL BECOME LIGHT/VRBL UNDER 5KT
TONIGHT, THEN ESE TO S DURING SUN MORNING.
MARINE
ISSUED AT 452 AM EST SAT FEB 22 2025
WSW GUSTS TO 20-25 KT ARE EXPECTED FOR MUCH OF TODAY ALONG WITH
WAVES OF 4-6 FEET. WINDS THEN FALL BELOW 20 KT AND WAVES FALL BELOW
3 FEET OVERNIGHT AND SUNDAY MORNING. SOUTH WINDS RAMP UP THROUGH THE
DAY SUNDAY, INCREASING TO 25 KT OVERNIGHT INTO MONDAY MORNING AHEAD
OF A CLIPPER LOW PASSING THROUGH NORTHERN ONTARIO. WINDS BECOME
WESTERLY, STILL GUSTING NEAR 25 KT ON MONDAY BEFORE FALLING BELOW 20
KT MONDAY NIGHT, THEN REMAINING NEAR OR BELOW 20 KT FOR MUCH OF THE
WEEK AS UNCERTAINTY GROWS REGARDING THE PATH OF ANY POTENTIAL
CLIPPER LOWS THROUGH NEXT WEEK. SHOULD A LOW PASS DIRECTLY OVER THE
LAKE, GALE POTENTIAL WOULD INCREASE TO 20-40%, BUT THERE IS MUCH
UNCERTAINTY REGARDING TIMING ANY LOW PRESSURE PASSAGES AT THIS TIME.
WAVES NEXT WEEK ARE EXPECTED TO BE AT THEIR PEAK NORTH AND NORTHEAST
OF THE TIP OF THE KEWEENAW PENINSULA MONDAY AS THE WESTERLY GUSTS
FORCE WAVES OF UP TO 8 FT.
MQT WATCHES/WARNINGS/ADVISORIES
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
SHORT TERM...ROLFSON
LONG TERM...GS
AVIATION...ROLFSON
MARINE...GS
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