Area Forecast Discussion
Issued by NWS Gaylord, MI

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FXUS63 KAPX 250432
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1232 AM EDT MON APR 25 2016

.UPDATE...
ISSUED AT 1029 PM EDT SUN APR 24 2016

NEARLY VERTICALLY-STACKED LOW PRESSURE REMAINS CENTERED OVER
PLAINS LATE THIS EVENING. ASSOCIATED WARM FRONT EXTENDS FROM THE
MAIN LOW CENTER OVER SOUTH DAKOTA EASTWARD THRU SRN
MINNESOTA...SRN WISCONSIN AND SRN LWR MICHIGAN. WIDESPREAD RAIN
CONTINUES TO DEVELOP ALONG AND NORTH OF THIS WARM FRONT...AND IS
STREAMING EASTWARD THRU MUCH OF OUR CWA. GREATEST COVERAGE NAS
BEEN ACROSS LOCATIONS ALONG AND SOUTH OF A LINE FROM ACB TO GOV TO
OSC WHERE DWPTS HAVE RISEN INTO THE LOWER 40S. SO FAR...PRECIP HAS
BEEN RATHER LIGHT AND MORE STRATIFORM IN NATURE. PRECIP HAS BECOME
A BIT MORE CONVECTIVE OVER WRN WISCONSIN WITH A FEW HITS OF
LIGHTNING NOW SHOWING UP AS WELL. LATEST RAP13 AND NAM12 BOTH
SUGGEST THUNDER IS UNLIKELY OVERNIGHT FOR OUR CWA AS ALL
INSTABILITY REMAINS WEST OF OUR CWA. HAVE MADE SOME MINOR
ADJUSTMENTS TO POPS EARLIER IN THE EVENING...AND HAVE OPTED TO
REMOVE ANY CHANCE OF THUNDER FOR THE REMAINDER OF THE NIGHT AS
THIS IS LOOKING UNLIKELY. OTHERWISE...EXPECT A WET AND COOL
BALANCE TO OUR NIGHT ACROSS NRN MICHIGAN...WITH PERIODS OF RAIN
AND OVERNIGHT LOWS RANGING FROM THE MID 30S IN ERN UPR MICHIGAN TO
THE LOWER 40S ACROSS OUR SRN CWA.

&&

.SHORT TERM...(THIS EVENING AND OVERNIGHT)
ISSUED AT 335 PM EDT SUN APR 24 2016

LOW PRESSURE STRETCHED OUT ACROSS THE WESTERN PLAINS WILL AMBLE
EASTWARD AND IMPACT THE FORECAST AREA OVER THE NEXT 36 HOURS OR SO.
THIS FEATURE IN COMBINATION WITH PIECES OF ENERGY EJECTING OUT OF
THE UPPER TROUGH WILL BRING A PERIOD OF UNSETTLED WEATHER THROUGH
EARLY TUESDAY. MEANWHILE...ASSOCIATED WARM FRONT WILL SET UP JUST TO
OUR SOUTH. THIS FRONT ALONG WITH ELEVATED INSTABILITY (LAPSE RATES
OF AROUND 6 TO 6.5 C/KM) COULD SPARK A FEW THUNDERSTORMS ALONG AND
SOUTH OF THE M-55 CORRIDOR OVERNIGHT. MEANWHILE...RAIN WILL CONTINUE
TO OVERSPREAD THE REGION AS LOWER LEVELS FINALLY OVERCOME DRY LOW
LEVELS AND SATURATE LATE THIS AFTERNOON AND CONTINUE THROUGH
TONIGHT. THE AXIS OF THE STEADIEST RAIN LOOKS LIKE IT WILL SET UP
SOMEWHERE ALONG AND PERHAPS NORTH OF THE M-32 CORRIDOR. GENERALLY
SPEAKING...RAINFALL AMOUNTS OF BETWEEN A QUARTER AND A HALF OF AN
INCH ARE EXPECTED (WITH AMOUNTS CLOSER TO THREE QUARTERS OF AN INCH
POSSIBLE ALONG THE M-32 CORRIDOR). LOWS TONIGHT RANGING FROM THE
CHILLY MIDDLE 30S NORTH TO THE MILDER MIDDLE 40S SOUTHWEST.

.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 335 PM EDT SUN APR 24 2016

HIGH IMPACT WEATHER POTENTIAL: MINIMAL.

PATTERN SYNOPSIS/EXPECTED EVOLUTION: MOST PROMINENT FEATURE OF
INTEREST IS LARGE AND COLD NORTHEAST CANADA CENTERED GYRE...WHICH
LOOKS TO BE LARGELY LOCKED IN PLACE FOR THE NEXT SEVERAL DAYS VIA
STRENGTHENING NEGATIVE NORTH ATLANTIC OSCILLATION SIGNATURE. THIS
SYSTEM WILL HAVE CONSIDERABLE INFLUENCE ON OUR WEATHER...INITIALLY
BY HELPING MAINTAIN OVERHEAD TIGHT THERMAL GRADIENT AND ATTENDANT
FGEN DRIVEN RAINS THROUGH MONDAY NIGHT...AND THEN BY LIKELY SHEARING
OUT/WEAKENING NEXT SOUTHERN STREAM WAVE ON ITS APPROACH INTO THE
GREAT LAKES REGION MIDWEEK.

PRIMARY FORECAST CONCERNS/CHALLENGES: FINE TUNING RAIN TRENDS MONDAY
AND MONDAY NIGHT. ADDRESSING POSSIBLE IMPACTS FROM THAT MIDWEEK
SYSTEM. TEMPERATURE TRENDS THROUGH THE FORECAST.

DETAILS: STILL LOOKING RATHER WET MONDAY INTO MONDAY NIGHT AS
CURRENT NORTHERN PLAINS WAVE SHEARS OUT ON ITS PASSAGE ACROSS THE
LAKES. NICE LOW LEVEL CONVERGENCE BULLSEYE REMAINS IN PLACE ACROSS
THE NORTHERN LAKES...WITH TIGHT THERMAL GRADIENT AND OVERHEAD UPPER
LEVEL DIVERGENCE REGIME (HINTS OF UPPER JET COUPLING) ONLY ADDING TO
LARGE SCALE LIFT. PERIODS OF RAIN...MODERATE AT TIMES...WILL BE THE
RESULT. STILL NOT ENTIRELY SOLD ON THE EXACT PLACEMENT OF BETTER
RAIN CORRIDOR...WITH SOME HINTS INITIAL BAND MAY SET UP ACROSS THE
TIP OF THE MITT/EASTERN UPPER MICHIGAN...WITH MORE AREA-WIDE RAINS
ARRIVING LATER IN THE DAY AS MAIN MID LEVEL WAVE ARRIVES. WHILE
SURFACE BASED WARM FRONT LOOKS TO REMAIN WELL TO OUR SOUTH (RAIN-
COOLED AIR SHOULD ONLY HELP WITH THIS SOUTHERN DISPLACEMENT)...SOME
INDICATIONS IN GUIDANCE OF SOME WEAK ELEVATED INSTABILITY SCRAPING
BY AREAS ALONG AND SOUTH OF M-55. MID LEVEL LAPSE RATES NOT TERRIBLY
IMPRESSIVE...HOWEVER. DON`T THINK THIS WILL BE A BIG DEAL...BUT HAVE
GONE AHEAD AND AT LEAST MENTIONED SOME THUNDER POSSIBILITY FOR
SOUTHERN AREAS...WHICH MATCHES WELL WITH LATEST SPC THUNDER PROGS.
RAIN INTENSITY EXPECTED TO DECREASE HEADING THROUGH MONDAY NIGHT AS
WHOLE SYSTEM REALLY BEGINS TO SHEAR OUT. CURRENT TRENDS CONTINUE TO
SUPPORT MOST...IF NOT ALL...OF THE PRECIPITATION ENDING BEFORE COLD
ENOUGH AIR ARRIVES FOR MUCH SNOW TO MIX IN.

RAINFALL TOTALS HAVE TRENDED DOWN IN NEARLY ALL GUIDANCE PROGS...BUT
STILL LOOKS LIKE ANOTHER HALF TO THREE QUARTERS OF AN INCH OF RAIN
IS DOABLE MONDAY THROUGH MONDAY NIGHT. THIS WILL BRING STORM TOTAL
AMOUNTS TO OVER AN INCH IN SOME LOCATIONS. RIVERS SHOULD BE ABLE TO
HANDLE THE ASSOCIATED RUNOFF...WITH LACK OF MORE INTENSE RAINFALL
RATES NEGATING MUCH OVERLAND FLOODING CONCERNS. AS SUCH...SEE NO
NEED TO MENTION ANY HEAVY RAIN CONCERNS IN OUR LATEST HAZARDOUS
WEATHER PRODUCTS.

THE THREAT FOR MEASURABLE RAIN SHOULD END RATHER QUICKLY HEADING
THROUGH TUESDAY MORNING AS MID AND UPPER LEVEL MOISTURE RAPIDLY
SCOUR OUT. UNFORTUNATELY...DOWN-LOW MOISTURE MAY NOT BE AS FAST TO
DO SO...PARTICULARLY FOR AREAS SOUTH OF THE BIG BRIDGE. EXPECT
CLOUDS TO DOMINATE NORTHERN LOWER MUCH OF THE MORNING...WITH PERHAPS
EVEN SOME LINGERING DRIZZLE. STILL EXPECT MOST AREAS TO SEE AT LEAST
SOME SUN BY LATER TUESDAY AFTERNOON. CLEARING COMPLETES THE PROCESS
RAPIDLY TUESDAY EVENING...SETTING THE STAGE FOR A RATHER CHILLY
OVERNIGHT...WHEN MOST AREAS WILL LIKELY DROP BELOW 30 DEGREES.

NEXT SOUTHERN STREAM WAVE MOVES OUT OF THE INTERMOUNTAIN WEST INTO
THE PLAINS LATER TUESDAY NIGHT AND WEDNESDAY. AS MENTIONED IN
OPENING PARAGRAPH...UPSTREAM CANADIAN BLOCKING WILL NOT
YIELD...ALLOWING SURFACE HIGH PRESSURE TO REMAIN WEDGED THROUGH THE
GREAT LAKES. SURE CANNOT ARGUE WITH INHERITED DRY FORECAST WITH JUST
SOME AFTERNOON INCREASING HIGH CLOUDS.

EXTENDED (WEDNESDAY NIGHT THROUGH SUNDAY)...

THE THEME IN THE EXTENDED APPEARS TO BE "GLANCING BLOWS" WHEN IT
COMES TO ANY APPRECIABLE RAINFALL IN THE CWA. THE EURO AND GFS
SWITCHED SOLUTIONS FROM YESTERDAY...EACH TAKING THE OTHERS STANCE ON
POPS FOR THURSDAY. WHATS GUMMING UP THE WORKS IS A BROAD LOW IN
NORTHERN QUEBEC THAT IS SUPPRESSING STORM TRACKS TO THE SOUTH OF THE
LAKES. THE MOISTURE ASSOCIATED WITH THE THURSDAY LOW WILL ADVANCE
INTO SOUTHERN MICHIGAN...BUT THE EXTENT NORTH THAT IT WILL PUSH IS
QUESTIONABLE. WILL KEEP CHANCE POPS GENERALLY ALONG AND SOUTH OF M55
ON THURSDAY FOR NOW. PRETTY DECENT AGREEMENT ON DRY CONDITIONS FOR
FRIDAY AND SATURDAY...BUT THEN WE SEE A REPLAY ON SUNDAY AS ANOTHER
LOW TRACKS GENERALLY SOUTH. RAIN SHIELD MAY ADVANCE A BIT FURTHER
NORTH WITH THIS SYSTEM...BUT TIMING IS UNCERTAIN. EURO SAYS
SUNDAY...GFS SAYS MONDAY...FOR NOW. BUT THATS A LONG WAY OFF TO DRAW
ANY CONCLUSIONS. TEMPERATURES WILL MODERATE TO NEAR NORMAL BY
FRIDAY...SATURDAY BEING THE WARMEST OF THE STRETCH...PUSHING THE 60
DEGREE MARK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1231 AM EDT MON APR 25 2016

LOW PRESSURE WILL SLOWLY EDGE EASTWARD TOWARD LOWER MICHIGAN OVER
THE NEXT 24 HRS. WIDESPREAD RAIN WILL CONTINUE TO IMPACT NRN LWR
MICHIGAN ALONG AND NORTH OF THE ASSOCIATED WARM FRONT. CONDITIONS
WILL DETERIORATE TO MVFR AND EVENTUALLY IFR AS LOW LEVEL MOISTURE
AND RAIN INTENSITY INCREASE THRU MONDAY. WINDS WILL REMAIN FROM THE
E/SE WINDS AT AROUND 10 KTS THRU THE 24 HR TAF PERIOD.

&&

.MARINE...
ISSUED AT 335 PM EDT SUN APR 24 2016

LOW PRESSURE FROM THE DAKOTAS WILL VERY SLOWLY WORK IT`S WAY
ACROSS SRN LOWER MICHIGAN BY EARLY TUESDAY. THE EASTERLY PRESSURE
GRADIENT TIGHTENS WITH TIME WHILE PERIODIC SHOWERS TONIGHT
THROUGH MONDAY NIGHT...EVEN A CHANCE FOR THUNDER ACROSS FAR
SOUTHERN MARINE ZONES OF LAKE MICHIGAN AND LAKE HURON. ADVISORY
LEVEL WINDS ARE A VIRTUAL LOCK FROM LATE TONIGHT THROUGH TUESDAY
MORNING. LOW END GALES ARE NOT OUT OF THE QUESTION...ESPECIALLY
THROUGH THE FAR NRN PORTIONS OF LAKES HURON AND
MICHIGAN...INCLUDING THE STRAITS. HOWEVER...THEY REMAIN OUT OF
THE FORECAST AS WE DO NOT THINK WE WILL BE ABLE TO MIX DEEP
ENOUGH TO GET ANYTHING MORE THAN A FEW ISOLATED GALE FORCE GUSTS.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR LHZ345>348.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 2 PM EDT TUESDAY
     FOR LHZ349.

LM...SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR LMZ341-342.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 2 PM EDT TUESDAY
     FOR LMZ323-344>346.

LS...SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ321-322.

&&

$$

UPDATE...MLR
SHORT TERM...SULLIVAN
LONG TERM...MSB/KAB
AVIATION...MLR
MARINE...SULLIVAN



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