457
FXUS63 KDTX 300357
AFDDTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1157 PM EDT WED APR 29 2026
KEY MESSAGES
- SHOWERS DIMINISH BEFORE SUNRISE TONIGHT. THERE ARE ADDITIONAL
MINOR CHANCES FOR LIGHT RAIN EACH AFTERNOON BOTH THURSDAY AND
FRIDAY.
- A STRETCH OF WELL BELOW AVERAGE TEMPERATURES WILL EXIST THROUGH
THIS WEEKEND AND BRING POTENTIAL FOR FROST/FREEZE CONDITIONS EACH
MORNING FRIDAY THROUGH SUNDAY.
AVIATION
SHOWERS INCREASING COVERAGE OVER SW LOWER MI LEADING UP TO MIDNIGHT
ARE ON THE WEST FLANK OF AN INTENSE SMALLER SCALE MID LEVEL
CIRCULATION THAT HAS SUPPORTED ACTIVITY OVER SE MI FOR MUCH OF THE
EVENING. THE UPSTREAM DEVELOPMENT MOVES EASTWARD WHILE SHRINKING IN
COVERAGE BUT STILL DEMANDS ACCOUNTING FOR ALONG THE TERMINAL
CORRIDOR FOR MUCH OF THE LATE NIGHT PERIOD. THE EXTRA BOUNDARY LAYER
MOISTURE ALSO SUSTAINS BORDERLINE MVFR/VFR CEILING IN AND NEAR THE
ASSOCIATED NW-SE SURFACE PRESSURE TROUGH AS IT GRADUALLY FILLS
TOWARD SUNRISE. A MORE NEUTRAL NW LOW LEVEL WIND THEN WORKS TO BRING
A LOW CLOUD DECREASE DOWN FROM NORTHERN LOWER MI WHILE MID CLOUDS
LINGER DURING THE MORNING. IT IS A COOLER FLOW THAT IS SUBJECT TO A
DAYTIME INSTABILITY BOOST OF CUMULUS THAT DEVELOPS INTO BROKEN
CEILING IN THE LOWER RANGE OF VFR BY AFTERNOON. A STRAY SHOWER IS
ALSO FAVORED IN THIS SETUP BUT WITH COVERAGE AND DURATION TOO LOW
FOR A TERMINAL MENTION FROM MID AFTERNOON INTO THURSDAY EVENING.
D21/DTW CONVECTION...NO THUNDERSTORMS EXPECTED THROUGH THIS TAF
PERIOD.
DTW THRESHOLD PROBABILITIES
* HIGH FOR CEILING AT OR BELOW 5,000 FEET TONIGHT AND THURSDAY.
PREV DISCUSSION
ISSUED AT 241 PM EDT WED APR 29 2026
DISCUSSION...
A NOTABLY COOLER ENVIRONMENT FIRMLY ENTRENCHED TODAY, AS AN INITIAL
PERIOD OF MEANINGFUL LARGE SCALE HEIGHT FALLS OCCUR ATOP PREVAILING
LOW LEVEL NORTHEAST FLOW. ASSOCIATED BROAD, WEAK ASCENT WITHIN THE
MOIST CYCLONIC FLOW WILL MAINTAIN SOME POCKETS OF LIGHT RAIN OR
DRIZZLE INTO THE EARLY EVENING HOURS. POTENTIAL FOR AN UPTICK IN
COVERAGE EARLY TONIGHT, AS GREATER HEIGHT FALLS TIED TO AN INBOUND
HIGHER AMPLITUDE WAVE SHIFTS AN INVERTED SURFACE TROUGH TOWARD THE
AREA. OVERALL MOISTURE QUALITY AND DEPTH SUPPORTIVE OF A CHAOTIC
COVERAGE AND WILL CONTINUE TO HIGHLIGHT POTENTIAL THRU THE EARLY
MORNING HOURS. THE LIKELIHOOD FOR A HIGHER COVERAGE OF CLOUD COVER
TO LINGER WELL INTO THE NIGHT, COMBINED WITH A PERSISTENT LIGHT
GRADIENT, WILL PROVIDE A HIGHER PROSPECTIVE FLOOR FOR LOW THURSDAY
MORNING. FORECAST WILL CONTINUE TO HIGHLIGHT READINGS RANGING FROM
MID 30S TO LOWER 40S. SOME PATCHY FROST PLAUSIBLE IN THIS
ENVIRONMENT, BUT WIDESPREAD COVERAGE APPEARS UNLIKELY.
UPPER LOW FORECAST TO ANCHOR NORTH OF LAKE SUPERIOR OVER THE NEXT 24
HOURS, EFFECTIVELY MAINTAINING A STRETCH OF COOLER AND POTENTIALLY
UNSETTLED CONDITIONS TO FINISH THE WORK WEEK. BRIEF BOUTS OF PVA AS
WEAK SHORTWAVE ENERGY TRANSIT THE EXISTING MID LEVEL CYCLONIC
PERIPHERY MAY COMBINE WITH STEEPENING DIURNALLY ENHANCED LAPSE RATES
TO OFFER A LOWER PROBABILITY FOR SHOWER PRODUCTION BOTH THURSDAY AND
FRIDAY. SLIGHTLY GREATER SIGNAL EXISTS FRIDAY, AS HIGHLIGHTED BY
LATEST BLENDED MODEL GUIDANCE. COLDEST CONDITIONS THIS PERIOD LIKELY
NOTED FRIDAY, AS A SECONDARY WINDOW OF COLD AIR ADVECTION DRAGS 850
MB TEMPERATURES BELOW -5C. HIGHS RANGING FROM MID 40S TO LOWER 50S.
FROST/FREEZE CONSIDERATIONS WILL EXIST, PARTICULARLY FRI NIGHT AS
OVERNIGHT TEMPERATURES MORE DEFINITELY PUSH BELOW FREEZING EARLY
SATURDAY MORNING.
HIGHER MAGNITUDE COLD FOR EARLY MAY STANDARDS WILL EXIST THROUGH
SATURDAY WITHIN DEEP LAYER NORTHWEST FLOW. DAYLIGHT TEMPERATURES
AGAIN STRUGGLING TO ECLIPSE 50 DEGREES. RESIDENT POLAR THERMAL
PROFILE WILL STEADILY VACATE STARTING SUNDAY WITHIN THE BACKDROP OF
MODEST HEIGHT RISES AND BRIEF WARM AIR ADVECTION AS LOW LEVEL FLOW
EMERGES FROM THE SOUTHWEST WITHIN THE IMMEDIATE WAKE OF EXITING
SURFACE RIDGING. A MORE SEASONABLE AIRMASS THEN ENTRENCHED HEADING
INTO EARLY NEXT WEEK. LARGE SCALE PATTERN MAINTAINS SOME LEVEL OF
GENERAL TROUGHINESS WITH A FAVORABLE TRAJECTORY FOR ADDITIONAL MID
LEVEL IMPULSES TO PIVOT THROUGH, SUGGESTING A POTENTIALLY WET
PATTERN MAY EMERGE AT TIMES DURING THE EARLY WEEK PERIOD.
MARINE...
UPPER TROUGHING HOLDS ACROSS THE GREAT LAKES THROUGH THE REMAINDER
OF THE WORK WEEK MAINTAINING COOLER, UNSETTLED WEATHER THOUGH LITTLE
TO NO THUNDERSTORM CHANCES AS A RESULT. LOW PRESSURE LIFTING OUT OF
THE OHIO VALLEY INTO THE EASTERN GREAT LAKES SHIFTS WINDS FROM THE
NORTHEAST TO NORTHWEST TONIGHT WITH THIS FLOW DIRECTION LARGELY
HOLDING THROUGH FRIDAY. SPEEDS STAY ON THE MODEST SIDE OWING TO A
FAIRLY DIFFUSE GRADIENT WITH GUSTS HOLDING AT OR BELOW 20KTS. PERIOD
OF HIGH PRESSURE FAVORED TO EMERGE THIS WEEKEND BEFORE THE UNSETTLED
PATTERN RETURNS TO START NEXT WORK WEEK.
DTX WATCHES/WARNINGS/ADVISORIES
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
AVIATION.....BT
DISCUSSION...MR
MARINE.......KDK
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