536
FXUS63 KAPX 261050
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
650 AM EDT SAT APR 26 2025
KEY MESSAGES
- QUIET WEATHER FOR THIS WEEKEND, WITH IMPROVING CONDITIONS
TODAY.
- SEVERE STORMS AND HEAVY RAIN POSSIBLE MONDAY NIGHT.
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 357 AM EDT SAT APR 26 2025
PATTERN/SYNOPSIS: LOW PRESSURE IS DEEPENING AS IT MOVES EAST
NEAR LK ONTARIO. HIGH PRESSURE OVER NORTHERN MN IS MOVING SE-
WARD. SOME SHOWERS ARE OCCURRING SE OF AN APN-HTL LINE. A
SIZABLE BAND OF DRIZZLE WITH SOME EMBEDDED HEAVIER PRECIP
ELEMENTS TRAILS THE SHOWER ACTIVITY.
FORECAST: THE SURFACE LOW WILL EJECT ACROSS NORTHERN NEW ENGLAND
LATE TODAY INTO TONIGHT. THE TRAILING HIGH IS CENTERED OVER
LOWER MI AT DAYBREAK SUNDAY. MOISTURE WILL GRADUALLY SHALLOW OUT
TODAY, WITH LEFTOVER PRECIP DIMINISHING WITH TIME, AND CLOUD
COVER TO FOLLOW. LIGHT SHOWERS AND/OR DRIZZLE WILL PERSIST PAST
8AM IN NE LOWER AND FAR SE UPPER MI (DRUMMOND ISL IN
PARTICULAR). PRECIP DEPARTS IN THE MORNING, AND PARTIAL SUNSHINE
BREAKS OUT IN NW LOWER/EASTERN UPPER MI BY MIDDAY. CLOUD COVER
THINS OUT FURTHER AFTER THAT, AND WITH THE LOSS OF DIURNAL
HEATING, SKIES SHOULD BE CLEAR SHORTLY AFTER DUSK. CLEAR SKIES
ARE THEN EXPECTED THRU THE NIGHT.
THE COOL INCOMING AIRMASS WILL TEMPS ON THE CHILLY SIDE, EVEN
WITH SOME SUNSHINE BREAKING OUT. HIGHS UPPER 40S TO MID 50S.
LOWS TONIGHT IN THE UPPER 20S TO NEAR 30F.
LONG TERM /SUNDAY THROUGH FRIDAY/
ISSUED AT 357 AM EDT SAT APR 26 2025
PATTERN SYNOPSIS/FORECAST:
BROAD CYCLONIC CIRCULATION OVER THE CENTRAL CONTINENT ATTM...WITH
DIFLUENCE AND ATTENDANT CONVECTIVE ACTIVITY OVER THE WESTERN US AS
NIBLETS LIFT THROUGH A LONGWAVE TROUGH OVER CALIFORNIA. RIDGE AXIS
LARGELY CENTERED OVER MANITOBA INTO THE DAKOTAS...WITH A SHARP
TROUGH AXIS DIGGING DOWN THE DOWNSTREAM SIDE OF THIS INTO THE UPPER
GREAT LAKES...HELPING TO PUNT THE NUISANCE, SLOW-MOVING BOUNDARY OUT
OF MICHIGAN. HOWEVER...COL REGION OVER THE CENTRAL US CONTINUES TO
TAKE SHAPE...AS FLOW GETS STRETCHED OUT BETWEEN AFOREMENTIONED HIGH
PRESSURE...AND GENERALIZED HIGH PRESSURE AND MID-LEVEL RIDGING OVER
THE GULF/SE US. BULK OF THE MOISTURE (PWATS AT OR ABOVE 1INCH)
REMAINS LARGELY ALONG AND SOUTH OF THIS BOUNDARY, WHICH STRETCHES
FROM TX/OK TO THE LOWER GREAT LAKES. INCREASINGLY
NORTHERLY/NORTHEASTERLY FLOW OUT OF CANADA, HOWEVER, HELPING TO DRY
THINGS OUT ACROSS THE UPPER MIDWEST INTO THE CENTRAL PLAINS IN THE
WAKE OF THE SHARP TROUGH AXIS...AND SUPPRESS NORTHWARD MOVEMENT OF
DEVELOPMENT ALONG SAID COL REGION OVER THE HIGH PLAINS.
SHORTWAVE TROUGH AXIS FINALLY DEPARTS THE REGION TODAY...AS RIDGE
AXIS AND ATTENDANT HIGH PRESSURE BUILDS EASTWARD TONIGHT INTO
SUNDAY. RETURN FLOW WILL ALREADY BE STRENGTHENING UPSTREAM AS
TROUGHING OVER THE WESTERN US LEADS TO STRONG CYCLOGENESIS OVER THE
NORTHERN/CENTRAL PLAINS. LONGWAVE PATTERN HAS HINTS OF AN OMEGA
BLOCK...BUT IT APPEARS MUCH LESS BLOCKY ATTM...AND FAR MORE
PROGRESSIVE...WITH THE TROUGH ALOFT AND ATTENDANT SW-NE ORIENTED
SURFACE RESPONSE CURRENTLY EXPECTED TO SLIDE ACROSS THE GREAT LAKES
TUESDAY...WITH QUITE A BIT OF FANFARE IN THE WAY OF
RAIN/THUNDERSTORM ACTIVITY (POTENTIALLY QUITE STRONG) THROUGH
TUESDAY...AND FALLING TEMPS THROUGH THE DAY TUESDAY BEHIND THE
FRONT. BEHIND THIS...HIGH PRESSURE LOOKS TO BUILD IN FOR THE MIDDLE
OF THE WEEK...BUT THIS MAY END UP BEING SHORT-LIVED...WITH
ADDITIONAL TROUGHING CROSSING THE CENTRAL US...LEADING TO ANOTHER
DISTURBANCE IN THE VICINITY OF THE OH VALLEY FOR LATE WEEK.
CURRENTLY, SIGNALS INDICATE A STRONG/SHARP TROUGH AXIS ALOFT
COULD DEVELOP AS IT PROGRESSES EASTWARD INTO EASTERN CANADA. STILL
QUITE A BIT OF TIME TO SORT OUT DETAILS WITH THIS...BUT COULD
INDICATE SOME POTENTIAL FOR A COOL SPELL TO START OFF THE MONTH OF
MAY.
PRIMARY FORECAST CONCERNS:
STRONG TO SEVERE STORMS AND LOCALLY HEAVY RAIN POSSIBLE MONDAY AND
TUESDAY...
POTENTIAL FOR STRONG TO SEVERE STORMS MONDAY NIGHT INTO TUESDAY...
VERY POSSIBLE MOST OF THE CWA STAYS DRY THROUGH MUCH OF MONDAY...AS
FLOW MAY RETAIN A SOUTHEASTERLY COMPONENT FOR A LONGER TIME, KEEPING
THE MOISTURE AT BAY. HOWEVER...WILL NEED TO WATCH UPSTREAM
CONVECTION TRACKING TOWARD OUR AREA FOR LATER IN THE AFTERNOON INTO
MONDAY NIGHT. A FAIRLY DRAMATIC INCREASE IN MOISTURE IS EXPECTED
MONDAY NIGHT, WITH PWATS LIKELY WELL IN EXCESS OF 1 INCH (ABOVE
NORMAL FOR THIS TIME OF YEAR)...AS DEWPOINTS JUMP UP INTO THE 50S OR
BETTER AHEAD OF THE DRY SLOT AND COLD FRONT ON OUR DOORSTEP AT SOME
POINT NEAR/AFTER MIDNIGHT MONDAY NIGHT INTO TUESDAY. CERTAINLY
LOOKING GOOD ATTM FOR A PERIOD OF OVERNIGHT/EARLY MORNING THUNDER
TUESDAY; WHILE WE MAY NOT HAVE DIURNAL HEATING FOR INSTABILITY
NEARLY AS WELL AS POINTS UPSTREAM WILL, THINK THE POTENTIAL INCREASE
IN MOISTURE COMBINED WITH EXPECTED LIFT AND CONVECTIVE INSTABILITY
GENERATION ALONG THE DRY SLOT SHOULD CERTAINLY BOOST STORM ACTIVITY.
DEEP-LAYER SHEAR INCREASES TO 40-50KTS OVERNIGHT AS THE NOCTURNAL
LOW-LEVEL JET STRENGTHENS OVERHEAD, WHICH SUPPORTS THE IDEA OF
ORGANIZED STORMS AND POTENTIAL FOR SEVERE WEATHER. CURRENTLY...THINK
THAT BROAD SW FLOW LINING UP GENERALLY PARALLEL TO THE BOUNDARY WILL
BE MORE LIKELY TO SUPPORT UPSCALE GROWTH AND MORE LIKELY A WIND
THREAT...PARTICULARLY WITH STRONG WIND FIELDS ALOFT. ELEVATED
INSTABILITY COULD ADD A HAIL THREAT TO THE MIX, PARTICULARLY WITH
UNIDIRECTIONAL FLOW THAT COULD SUPPORT SOME STORM SPLITS/LEFT-MOVING
CELLS (THAT TEND TO BE HAIL PRODUCERS). TORNADOES AREN'T OUT OF THE
QUESTION, EVEN HERE, AS THEY COULD BE EMBEDDED WITHIN LINEAR
CONVECTION...OR IF ANYTHING GETS KICKED OFF AHEAD OF THE LINE AND
RUNS SOLO, GIVEN STRONG SHEAR IN THE LOW-LEVELS (THOUGH BETTER SHOT
AT THIS LATTER IDEA SHOULD BE TO OUR WEST).
POTENTIAL FOR LOCALLY HEAVY RAIN MONDAY NIGHT INTO TUESDAY... NOT
IMPOSSIBLE EVERYTHING GETS MESSED UP BY UPSTREAM CONVECTION SUNDAY
NIGHT INTO MONDAY EITHER...NOTING WE WILL BE JUST DOWNSTREAM FROM
SOME STEEPER LAPSE RATES ALOFT THAT COULD INDICATE SOME
CAPPING...THOUGH GUIDANCE SOUNDINGS SUGGEST IT WILL BE QUITE MOIST
ABOVE ANY EXPECTED INVERSION...SUCH THAT THIS MAY NOT BE A "TYPICAL"
CAPPED ELEVATED-MIXED-LAYER SETUP THAT WOULD BRING CONCERNS FOR
RIDGE-RIDING MCSS TOWARD OUR AREA. STILL...DO THINK IT IS A CONCERN
THAT WE WILL HAVE STEEP LAPSE RATES AROUND WITH THIS MOISTURE...AS
IT POSES A THREAT FOR A BETTER BANG FOR OUR QPF BUCK WITH THIS
SYSTEM. IF THIS LOWER PROBABILITY IDEA DOES COME TO FRUITION...OF
UPSTREAM CONVECTION TRACKING INTO OUR AREA...THIS COULD LEAD TO MORE
RAINFALL THAN CURRENTLY EXPECTED FOR OUR AREA. FOR NOW,
THOUGH...SIGNALS POINT TOWARD BEST RAINFALL POTENTIAL TO BE TO OUR
NORTH/NORTHWEST OVER CANADA. MORE PROGRESSIVE NATURE OF THE SYSTEM
ALSO SUGGESTS OUR RESIDENCE TIME UNDER BETTER RAINFALL MAY BE
SOMEWHAT LIMITED...THOUGH DO WONDER IF THE SW-NE ORIENTATION OF THE
FRONT COULD LEAD TO SOME LONGER RESIDENCE TIME UNDER RAINFALL AFTER
ALL.
AVIATION /12Z TAFS THROUGH 12Z SUNDAY/
ISSUED AT 650 AM EDT SAT APR 26 2025
WIDE MIX OF CONDITIONS THIS MORNING. MOST PLACES MVFR TO IFR IN
LOWER CIGS AND -DZ. CONDITIONS IMPROVE TODAY, AS LOW-LEVEL
MOISTURE DECREASES. CIGS IMPROVE TO VFR BY EARLY AFTERNOON, AND
SKIES SHOULD BE CLEAR TONIGHT.
NORTHERLY WINDS WILL BE SOMEWHAT BRISK TODAY, WITH LIGHT WINDS
TONIGHT.
APX WATCHES/WARNINGS/ADVISORIES
MI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LHZ348-
349.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ345-
346.
SHORT TERM...JZ
LONG TERM...FEF
AVIATION...JZ
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page