402
FXUS63 KDTX 241033
AFDDTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
633 AM EDT FRI JUL 24 2026
KEY MESSAGES
- DRY CONDITIONS WITH NEAR NORMAL TEMPERATURES ARE EXPECTED THROUGH
SATURDAY.
- HEAT AND HUMIDITY BUILD BACK INTO THE REGION SUNDAY-MONDAY WITH
HIGHS AROUND 90 DEGREES AND HEAT INDICES IN THE LOW TO MID 90S.
- ISOLATED STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE SUNDAY, WITH
A MORE ORGANIZED STRONG TO SEVERE WEATHER THREAT LOOKING TO ARRIVE
MONDAY.
AVIATION
EXPANSIVE HIGH PRESSURE ACROSS THE EASTERN GREAT LAKES WILL MAINTAIN
STRONG STABILITY AND LIGHT WINDS ACROSS SOUTHEAST MICHIGAN TODAY,
ENSURING A CONTINUED DRY FORECAST. SUBTLE LOW LEVEL MOISTURE AND
STEEP DAYTIME LAPSE RATES WILL RESULT IN A SCATTERED HIGH BASED CU
FIELD AMIDST AREAS OF CIRRUS.
D21/DTW CONVECTION...NO THUNDERSTORMS FORECAST.
DTW THRESHOLD PROBABILITIES
* NONE.
PREV DISCUSSION
ISSUED AT 333 AM EDT FRI JUL 24 2026
DISCUSSION...
LONGWAVE TROUGHING PATTERN HOLDS IN PLACE THIS MORNING OVER EASTERN
CONUS, WITH AN EMBEDDED SHORTWAVE RACING ACROSS THE CENTRAL PLAINS.
HIGH BASED CIRRUS ASSOCIATED WITH THIS WAVE AND CONVECTIVE CLOUD
DEBRIS CLIP THE SOUTHERN GREAT LAKES, BUT OTHERWISE SURFACE HIGH
PRESSURE SUCCESSFULLY KEEPS MOISTURE WELL TO OUR SOUTH TO SUPPORT
PLENTY OF SUNSHINE AND DRY WEATHER. THE COMPLEMENTARY THERMAL TROUGH
KEEPS HIGHS A FEW DEGREES COOLER THAN NORMAL TODAY--IN THE LOW 80S,
WITH A COUPLE DEGREE BOOST INTO THE MID-80S SATURDAY.
DRY CONDITIONS PERSIST SATURDAY, BUT WITH A PATTERN SHIFT ON ITS WAY
AS WINDS ORGANIZE OUT OF THE SOUTHWEST DURING THE DAY. ALOFT, MID-
LEVEL HEIGHTS RISE MODESTLY IN RESPONSE TO RIDGE AMPLIFICATION OVER
WESTERN CONUS AND THE SOUTHERN PUSH OF A STRENGTHENING HUDSON BAY
LOW. THIS DRAWS THE THETA-E GRADIENT EAST, FOLDING INSTABILITY INTO
THE SAGINAW VALLEY AND THUMB REGION EARLY SUNDAY MORNING WHICH
EXPANDS SOUTH AND EAST THROUGH THE DAY. MULTIPLE WAVES RIPPLE AROUND
THE RIDGE SUNDAY, ATTEMPTING TO ENGAGE THE DESTABILIZING AIRMASS AND
GENERATE SHOWERS AND THUNDERSTORMS. TIMING OF THESE WAVES IS STILL
UNCERTAIN, ALTHOUGH THE LATEST 00Z/06Z GUIDANCE FAVORS A ROUND OF
MORNING CONVECTION AND A SECOND ROUND OF CONVECTION AROUND PEAK
HEATING. OPTED FOR MORE BULLISH POPS ACROSS THE SAGINAW VALLEY/THUMB
SUNDAY MORNING GIVEN THE STRONG SYNOPTIC SUPPORT AS THE LEFT EXIT
REGION OF AN ~85 KNOT JET CLIPS ATOP THE BUILDING INSTABILITY.
MUCAPE WILL STILL BE RAMPING UP THOUGH, SO ONLY ADVERTISING A SLIGHT
CHANCE OF THUNDER WITH THIS ACTIVITY. LINGERING DRY AIR AND/OR
SUBSIDENCE FROM PRIOR CONVECTION WILL THEN BE HURDLES TO OVERCOME
SUNDAY AFTERNOON, BOTH OF WHICH COULD STALL THE EASTWARD PROGRESS OF
MOISTURE AND INSTABILITY. THAT SAID, IF DEEP CONVECTION CAN DEVELOP
IN THIS ENVIRONMENT, STORMS MAY BECOME ORGANIZED GIVEN THE STRONG
SHEAR PROFILES (35-40 KNOTS 0-6 KM BULK SHEAR). THIS IS SUPPORTED BY
THE LATEST SWODY3 MARGINAL RISK AND CSU MACHINE LEARNING
PROBABILITIES.
THUNDERSTORM CHANCES CONTINUE SUNDAY NIGHT THROUGH EARLY NEXT WEEK
AS SE MICHIGAN REMAINS ON THE EDGE OF THE INSTABILITY GRADIENT UNDER
AN ACTIVE NORTHWESTERLY JET AND WAVE TRAIN. BEST OPPORTUNITY FOR
ORGANIZED SEVERE WEATHER COMES SOMETIME EARLY NEXT WEEK AS THE LOW
CURRENTLY OFF THE COAST OF THE PACIFIC NORTHWEST RELEASES EAST
AROUND THE RIDGE AND INDUCES CYCLOGENESIS. MAJORITY OF DETERMINISTIC
MODELS AND ENSEMBLE MEMBERS BRING THIS WAVE TO THE GREAT LAKES
REGION MONDAY NIGHT, ALTHOUGH A SMALLER SUBSET DELAYS THAT UNTIL
TUESDAY. THE STRONG SYNOPTIC SIGNAL IN THE GUIDANCE LEANS TOWARD
ORGANIZED SEVERE WEATHER POTENTIAL.
OUTSIDE OF THUNDERSTORM CHANCES, THE UPSTREAM RIDGE SENDS HEAT AND
HUMIDITY INTO SE MICHIGAN BEGINNING SUNDAY AND LASTING UNTIL THE
SYNOPTIC COLD FRONT COMES THROUGH MID-WEEK. FORECAST HIGHS IN THE
UPPER 80S-LOW 90S CARRY LOW CONFIDENCE GIVEN THE THUNDERSTORM
POTENTIAL AND CLOUD DEBRIS. HEAT INDICES IN THE MID-90S WILL BE
ATTAINABLE IF A DRIER OUTCOME MATERIALIZES.
MARINE...
WINDS WILL BE LIGHT SOUTHERLY TODAY AS HIGH PRESSURE RESIDING OVER
THE MID ATLANTIC STATES STILLS EXERTS IT INFLUENCE. A SURFACE TROUGH
SLOWLY PASSING THROUGH DURING THE WEEKEND WILL BRING A CHANCE OF
SHOWERS AND ISOLATED THUNDERSTORMS, THOUGH WINDS ARE EXPECTED TO
REMAIN LIGHT.
THE NEXT NOTABLE STORM SYSTEM ARRIVES ON MONDAY, AS LOW PRESSURE
TRACKS ACROSS THE NORTHERN GREAT LAKES. STRONG THUNDERSTORMS ARE
POSSIBLE AS THE COLD FRONT WORKS THROUGH THE CENTRAL GREAT LAKES
DURING THE EVENING HOURS. NORTHERLY WINDS BEHIND THIS SYSTEM LATE
MONDAY NIGHT INTO TUESDAY HAVE THE POTENTIAL TO REACH 25 KNOTS OVER
SOUTHERN LAKE HURON.
HYDROLOGY...
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS ARE POSSIBLE SUNDAY INTO
EARLY NEXT WEEK. AN INCREASINGLY HUMID AND UNSTABLE AIRMASS WILL
LEAD TO RAINFALL RATES OVER AN INCH PER HOUR IN SOME THUNDERSTORMS.
RECENT DRY WEATHER AND LOW SOIL SATURATION WILL HELP MITIGATE
WIDESPREAD FLOODING CONCERNS, ALTHOUGH LOCALIZED FLASH FLOODING OF
LOW-LYING, URBAN, AND OTHER FLOOD-PRONE AREAS REMAINS POSSIBLE IF
THUNDERSTORMS REPEATEDLY IMPACT THE SAME LOCATIONS.
DTX WATCHES/WARNINGS/ADVISORIES
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
AVIATION.....SC
DISCUSSION...MV
MARINE.......SF
HYDROLOGY....MV
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AT WWW.WEATHER.GOV/DETROIT.
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