065
FXUS63 KMPX 100042
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
642 PM CST THU JAN 9 2025
KEY MESSAGES
- BAND OF LIGHT SNOW WILL CONTINUE TO TRANSLATE EAST THROUGH THE
EARLY EVENING HOURS. MINOR ACCUMULATIONS AND A FEW SLICK
SPOTS EXPECTED.
- A CLIPPER SYSTEM WILL BRING THE RETURN OF LIGHT SNOW TO THE
REGION LATE SATURDAY INTO SUNDAY. FEW INCHES OF ACCUMULATION
LIKELY.
- MUCH COLDER EARLY NEXT WEEK, WITH SUB-ZERO LOWS EXPECTED.
DISCUSSION
ISSUED AT 242 PM CST THU JAN 9 2025
REGIONAL MRMS DISPLAY CAPTURES A NORTH TO SOUTH ORIENTED BAND OF
SNOW TRAVELING EAST ACROSS CENTRAL/SOUTHERN MINNESOTA THIS
AFTERNOON. THE HEAVIEST SNOW IS REPORTED ALONG AND NORTH OF
I-94, WHERE SURFACE OBSERVATIONS CAPTURE VISIBILITY BELOW 1
MILE. MNDOT CAMERAS SHOW THE MINOR ACCUMULATION (GENERALLY AN
INCH OR LESS) ACROSS WESTERN COMMUNITIES. THE BEST FORCING IS
LIFTING INTO NORTHERN MINNESOTA, SUCH THAT SNOWFALL RATES WILL
BECOME LOWER WITH EASTERN EXTENT THIS AFTERNOON. THE GOING
FORECAST REMAINS ON TRACK THROUGH THIS EVENING, WITH ADDITIONAL
SNOWFALL EXPECTED TO REMAIN BELOW A HALF INCH ACROSS
SOUTHEASTERN MINNESOTA & WESTERN WISCONSIN. THE BEST CHANCE FOR
SLIGHTLY HIGHER AMOUNTS WILL BE NORTH OF I-94 IN EASTERN
MINNESOTA, DUE TO THE BETTER FORCING REFERENCED ABOVE. WHILE
THIS IS A LOW IMPACT EVENT, THERE WILL BE ENOUGH SNOW TO CREATE
SLICK SPOTS ON AREA ROADWAYS.
A VORTICITY LOBE CENTERED OVER CENTRAL MANITOBA IS PROGGED TO
PINWHEEL SOUTHEAST INTO NORTHERN MINNESOTA OVERNIGHT. THE
PRESENCE OF LIFT ASSOCIATED WITH THE VORT LOBE WILL WORK IN
TANDEM WITH THE NORTHWESTERLY FLOW REGIME TO PRODUCE FLURRIES
TONIGHT AND TOMORROW. TRADITIONALLY, THIS TYPE OF SETUP HAS
PRODUCED BURSTS OF SNOWFLAKES WITH BRIEF REDUCTIONS IN
VISIBILITY, THOUGH LITTLE TO NO ACCUMULATION. FORECAST SOUNDINGS
CAPTURE THIS SCENARIO WITH A SHALLOW, BUT SATURATED DGZ IN THE
LOWEST 5K FEET ALONG WITH MODERATE OMEGA FORCING. LOW-LEVEL
LAPSE RATES APPEAR TO BE TOO STABLE FOR THE DEVELOPMENT OF MORE
PRONOUNCED "CONVECTIVE" SNOW SHOWERS. A QUIET PERIOD IS ON TAP
FRIDAY INTO SATURDAY, AS WINDS GENTLY FLIP OUT OF THE SOUTH
AHEAD OF THE NEXT INCOMING SYSTEM.
NO MAJOR CHANGES WITH THE GOING TREND FOR A PERIOD OF
ACCUMULATING SNOW SATURDAY NIGHT INTO SUNDAY MORNING. WE'VE
FOLLOWED THE TREND OF THE OVERNIGHT SHIFT TO BUMP UP NBM POPS A
TAD SO THAT LOCATIONS GENERALLY ALONG AND NORTH OF I-94
(INCLUDING THE TC METRO) CARRY 70- 80% POPS. STORM TOTAL QPF
CLOSELY REFLECTS THAT OF THE GLOBAL ENSEMBLE MEANS, WITH ~0.1"
ALONG AND NORTH OF I-94. LESSER AMOUNTS, SAY NEAR 0.05" LIQUID
ARE FOUND TO THE SOUTHWEST TOWARDS THE MINNESOTA RIVER. A GLANCE
AT THE 12Z EPS REVEALED A SLIGHT NORTHERN SHIFT, WITH DRIER
AMOUNTS ACROSS SOUTHERN MINNESOTA. WE'LL WATCH TO SEE IF THE
NORTHERN SHIFT BECOMES A TREND IN FORTHCOMING FORECASTS, AS THAT
WOULD LOWER THE POTENTIAL FOR HIGHER QPF AMOUNTS CLOSER TO
~0.2" OR SO. NBM SLR'S BETWEEN 15-18:1 SEEM REASONABLE FOR THIS
CLIPPER SETUP AND A QUICK CALCULATION REVEALS 1-2" OF SNOW FOR
MOST LOCATIONS. COMMUNITIES NORTH OF I-94 COULD SEE AMOUNTS
CLOSER TO 3" GIVEN A LONGER DURATION SNOWFALL NORTH OF THE
SURFACE LOW.
GUSTY NORTHWESTERLY WINDS WILL USHER IN COLDER AIR FOLLOWING THE
DEPARTURE OF THE SYSTEM. LOWS ARE FORECAST TO DIP TO NEAR OR
BELOW ZERO MONDAY, WITH WIDESPREAD SUB-ZERO LOWS APPEARING MORE
LIKELY TUESDAY. WIND CHILLS WILL DROP INTO THE -15 TO -25 BELOW
ZERO RANGE EARLY IN THE WEEK. SINGLE DIGIT HIGHS MONDAY &
TUESDAY WILL BEGIN TO WARM BY MIDWEEK. THE WARMING TREND WILL
PRECEDE THE NEXT ITERATION IN THE PARADE OF WINTRY WAVES, WHICH
IS SET TO SLIDE THROUGH THE GREAT LAKES DURING THE MIDDLE TO END
OF NEXT WEEK. CONFIDENCE IS LOW THE CURRENT TRACK, HOWEVER I
THINK MANY FOLKS WILL WELCOME THE LOW 30S ON THURSDAY, AS
CURRENTLY ADVERTISED BY THE NBM.
AVIATION /00Z TAFS THROUGH 00Z FRIDAY/
ISSUED AT 614 PM CST THU JAN 9 2025
SWATH OF SNOW EXTENDING FROM WESTERN WI INTO SOUTHEAST MN
CONTINUES TO SLIDE OFF TO THE EAST, WITH SITES HAVING VISIBILITY
DROPPING TO AROUND 2SM UNDER THE HEAVIEST BANDS. THE SNOW WILL
LAST UNTIL 02Z AT THE LATEST IN MN AND TO 04Z AT THE WI SITES,
THEN ONLY OCCASIONAL FLURRIES EXPECTED THEREAFTER, PARTICULARLY
FOR DURING THE DAY FRIDAY BUT NO IMPACTS ARE EXPECTED. THE MAIN
FLIGHT CONDITION DEGRADATION THROUGH TOMORROW WILL BE ATTRIBUTED
TO MVFR CEILINGS OVERNIGHT THROUGH MOST OF FRIDAY. WINDS WILL
GENERALLY COME FROM THE NORTHWEST THROUGHOUT THIS DURATION WITH
SPEEDS UNDER 10KTS.
KMSP...CONDITIONS ARE EXPECTED TO IMPROVE FAIRLY QUICKLY WITHIN
THE FIRST COUPLE HOURS OF THE 10/00Z TAF AS THE SNOW ENDS.
VISIBILITY WILL IMPROVE TO VFR LEVELS BUT CEILINGS WILL BOUNCE
BETWEEN VFR AND MVFR LEVELS THROUGH LATE FRIDAY AFTERNOON.
/OUTLOOK FOR KMSP/
SAT...VFR. IFR/SN OVERNIGHT. WIND S 5-10KTS.
SUN...MVFR/IFR/SN EARLY. WIND NW 10-15G25KTS.
MON...VFR. WIND NW 5-10KTS.
MPX WATCHES/WARNINGS/ADVISORIES
MN...NONE.
WI...NONE.
DISCUSSION...STRUS
AVIATION...JPC
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page