189
FXUS63 KDTX 190801
AFDDTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
301 AM EST FRI DEC 19 2025
KEY MESSAGES
- MUCH COLDER TODAY WITH HIGHS IN THE 20S AND WIND CHILLS IN THE
TEENS TO SINGLE DIGITS. UNTREATED SURFACES WILL BE SLICK AS RESIDUAL
MOISTURE FREEZES EARLY THIS MORNING.
- GUSTY WEST-NORTHWEST WINDS TO 30-40MPH THROUGHOUT THE DAYLIGHT
HOURS TODAY. STRONGEST WINDS OCCUR THIS AFTERNOON WHEN A FEW LOWER
40MPH GUSTS WILL BE POSSIBLE.
- SCATTERED-NUMEROUS LIGHT SNOW SHOWERS THIS MORNING-AFTERNOON, WITH
ISOLATED EMBEDDED SNOW SQUALLS POSSIBLE INTO THE AFTERNOON. SNOWFALL
ACCUMULATIONS OF A DUSTING TO HALF INCH FOR MOST AREAS THOUGH
AMOUNTS NEAR AN INCH POSSIBLE IN THE HEAVIEST ACTIVITY.
DISCUSSION
SECONDARY ARCTIC COLD FRONT IS PUSHING EAST OF THE AREA EARLY THIS
MORNING USHERING IN SIGNIFICANTLY COLDER AIR WITH ALL OF SE MI
SEEING TEMPS FALL INTO THE MID 20S BY MID-MORNING. THIS RAPID COOL
DOWN WILL LEAD TO ANY UNTREATED SURFACES WITH LINGERING WATER FROM
YESTERDAY'S MELT/RAIN QUICKLY BECOMING SLICK/ICY. WITH THE CORE OF
THE AIRMASS NOT ARRIVING OVER LOWER MI UNTIL LATE MORNING-AFTERNOON,
COMBINATION OF REMNANT SYNOPTIC MOISTURE AND LAKE FLUX SUPPORTS
SCATTERED TO NUMEROUS LAKE EFFECT SNOW SHOWERS THROUGH THE FIRST
HALF OF THE DAY. OVERALL ACCUMULATIONS STAY LIGHT, FROM A DUSTING TO
AROUND A HALF INCH FOR MOST AREAS. THERE REMAINS SIGNAL IN A SUBSET
OF HIGH RES RUNS (LIKE THE HRRR) FOR THE TRAILING TROUGH AXIS OVER
CENTRAL LOWER MI TO AFFORD SOME DEGREE OF A LOWER LEVEL CONVERGENCE
AXIS AS IT PUSHES INTO THE SAGINAW VALLEY/THUMB. WHILE THIS WOULD
LEAD TO AN ENHANCEMENT OF LOCAL SNOW RATES, ITS TRANSIENT NATURE DUE
TO RELIANCE ON THE TROUGH STILL KEEPS AMOUNTS LIGHT (AOB 1 INCH).
WORTH NOTING HOWEVER THE OVERALL CONFIDENCE IN THIS FEATURE
MANIFESTING IS STILL FAIRLY LOW. SNOW SHOWER ACTIVITY BEGINS WINDING
DOWN LATE AFTERNOON AS DRIER AIR IS FULLY ADVECTED INTO THE LOWER MI
GRADUALLY TAPERING OF THE LAKE RESPONSE.
MAIN STORY FOR TODAY IS THE RETURN OF BELOW NORMAL TEMPS AND WINDS.
AS MENTIONED ABOVE, CORE OF THIS COLDER AIRMASS (850MB TEMPS -15C)
IS ADVECTED IN OVER THE COURSE OF THE MORNING AND AFTERNOON
RESULTING IN ESSENTIALLY NO THERMAL RECOVERY THROUGH THE DAY.
INSTEAD TEMPERATURES CREEP DOWN TOWARDS THE LOWER 20S BY EARLY
AFTERNOON AND STAY THERE THROUGH TONIGHT. THIS ALSO LEADS TO
INCREASING WINDS WITH AFTERNOON GUSTS REACH THE MID/UPPER 30KT
RANGE. MODEL SOLUTIONS THAT PUSH 40KTS (OR 45MPH WIND ADVISORY
CRITERIA) REMAIN VERY MUCH A MINORITY SO RUNNING FORECAST WILL
CONTINUE TO HIGHLIGHT PEAK GUSTS OF 35-40MPH WITH ONLY A FEW
ISOLATED PUSHING LOWER 40MPH. RESULTANT WIND CHILLS HOLD IN THE
LOWER TEENS TO SINGLE DIGITS THROUGHOUT THE DAY AND TONIGHT.
A MODERATION IN TEMPERATURES OCCURS SATURDAY AS MID-LEVEL RIDGING
QUICKLY SLIDES OVER THE OHIO VALLEY/SOUTHERN GREAT LAKES SETTING UP
MODEST SOUTHERLY WAA. 850MB TEMPS CLIMB BACK AROUND 0-2C SUPPORTING
HIGH TEMPS IN THE MID TO UPPER 30S (NEAR 40S TOWARDS THE OHIO
BORDER). WARM-UP IS SHORT-LIVED HOWEVER AS LOW PRESSURE TRACKING
OVER NORTHERN ONTARIO DRIVES ANOTHER ARCTIC COLD FRONT ACROSS THE
GREAT LAKES SATURDAY NIGHT. SOME SNOW/RAIN-SNOW SHOWERS ARE POSSIBLE
ALONG THE FRONT THOUGH THE DETACHMENT FROM THE PARENT SHORTWAVE
KEEPS ANY ACTIVITY VERY LIGHT WITH MINIMAL QPF. SUNDAY LOOKS TO BE
THE COLDEST DAY OF THE WEEK AS -15 TO -17C 850MB TEMPS SLIDE
DIRECTLY OVER LOWER MI LEADING TO HIGH TEMPS STRUGGLING TO GET INTO
THE MID 20S.
LONGER RANGE MODELS ARE IN PRETTY GOOD AGREEMENT FOR A PATTERN SHIFT
NEXT WORK WEEK AS AMPLIFYING UPPER LEVEL RIDGING BUILDS ACROSS THE
CENTRAL CONUS. THIS WOULD SUPPORT ABOVE NORMAL (POTENTIALLY MUCH
ABOVE NORMAL) TEMPERATURES FOR THE MID/LATE WEEK PERIOD.
MARINE
GALE WARNINGS ARE IN EFFECT FOR ALL OF LAKE HURON THIS MORNING AS
POST-FRONTAL WEST/NORTHWEST FLOW DRAWS A MUCH COLDER AIRMASS INTO
THE REGION. WELL-MIXED BOUNDARY LAYER CONDITIONS RESULT IN EFFICIENT
MOMENTUM TRANSFER THAT SUPPORTS ANOTHER PERIOD OF 35-40 KNOT GUSTS
FOR BOTH THE NEARSHORE ZONES AND OPEN WATERS. THE COLDER AIR HAS
ALSO ACTIVATED THE LAKE EFFECT RESPONSE, WHICH RAISES CONCERN FOR
SNOW SQUALLS THROUGHOUT THE DAY. HIGH PRESSURE EASES THE WIND FIELD
AND LAKE RESPONSE TONIGHT, LEADING TO A QUIETER PERIOD THAT EXTENDS
THROUGH DAYTIME SATURDAY. ANOTHER LOW PRESSURE SYSTEM, HOWEVER,
FILLS IN QUICKLY BEHIND IT TO BRING A COLD FRONT AND ELEVATED WIND
POTENTIAL TO THE GREAT LAKES SATURDAY NIGHT-SUNDAY. GIVEN THE
COMPLEX NATURE OF TODAY'S HEADLINES, WILL FOREGO ADDING ANOTHER
HEADLINE TO THE MIX FOR SATURDAY NIGHT EVEN THOUGH CONFIDENCE
GENERALLY MEETS CRITERIA FOR A WATCH.
PREV DISCUSSION
ISSUED AT 1144 PM EST THU DEC 18 2025
AVIATION...
STRONG COLD AIR ADVECTION WILL BE ONGOING THROUGH THE MORNING.
OBSERVATIONAL ANALYSIS SUGGESTS A FEW HOURS OF PREVAILING VFR BASED
CONDITIONS UNTIL A SECONDARY INFLUX OF LOW LEVEL MOISTURE FROM THE
WEST DROPS CONDITIONS BACK DOWN TO MVFR AFTER 09 OR 10Z. THIS
SECONDARY MOISTURE PUSH IN COMBINATION WITH ENHANCEMENT OFF LAKE
MICHIGAN WILL SUPPORT NUMEROUS SNOW SHOWERS DURING THE MORNING. THE
MORE FOCUSED REGION OF LOW LEVEL CONVERGENCE IS EXPECTED ACROSS PTK
AND FNT. THE BREVITY OF THE BETTER FORCING SUGGESTS SNOW ACCUMS WILL
BE LESS THAN AN INCH. THE SUSTAINED COLD AIR ADVECTION AND STRONG
LOW LEVEL WESTERLY WIND FIELDS WILL SUPPORT AMPLE MIXING ON FRIDAY,
ESPECIALLY DURING THE AFTERNOON. MODEL SOUNDINGS SUPPORT GUSTS IN
THE 30 TO 35 KNOT RANGE.
FOR DTW...WEST TO SOUTHWEST WINDS WILL TURN MORE TOWARD THE WEST
AROUND 17Z FRIDAY. PEAK GUSTS ARE FORECAST IN THE EARLY AFTERNOON
BEFORE THE GRADIENT FLOW WEAKENS AND NOCTURNAL COOLING SETS IN
TOWARD EVENING.
DTW THRESHOLD PROBABILITIES...
* HIGH IN CEILINGS AOB 5000 FEET TONIGHT AND FRIDAY. LOW FRIDAY
NIGHT.
* HIGH IN PRECIPITATION TYPE BEING SNOW FRIDAY MORNING.
* MEDIUM IN CROSSWINDS THRESHOLDS BEING EXCEEDED FROM 11 AM TO 4 PM
ON FRIDAY.
DTX WATCHES/WARNINGS/ADVISORIES
MI...NONE.
LAKE HURON...GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361>363-421-422-
441>443-462>464.
LOW WATER ADVISORY UNTIL 7 PM EST THIS EVENING FOR LHZ422.
LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LCZ460.
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LEZ444.
LOW WATER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LEZ444.
DISCUSSION...KDK
MARINE.......MV
AVIATION.....SC
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