Area Forecast Discussion
Issued by NWS Gaylord, MI

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000
FXUS63 KAPX 171047
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
647 AM EDT SUN AUG 17 2014

.SYNOPSIS...
ISSUED AT 312 AM EDT SUN AUG 17 2014

CANADIAN HIGH PRESSURE WILL GRADUALLY WORK THROUGH THE REGION TODAY
INTO MONDAY...DELIVERING A RETURN TO DRY AND QUITE COMFORTABLE LATE
AUGUST WEATHER. CHANCES FOR SHOWERS AND A FEW THUNDERSTORMS WILL BE
ON THE INCREASE MONDAY NIGHT THROUGH MIDWEEK...AS SLOW MOVING LOW
PRESSURE MEANDERS THROUGH THE GREAT LAKES.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 312 AM EDT SUN AUG 17 2014

THE FRONTAL BOUNDARY WHICH SLOWLY DROPPED SOUTH ACROSS THE GREAT
LAKES SATURDAY HAS FINALLY EXITED INTO SOUTHERN LOWER
MICHIGAN...WHILE A LARGE AREA OF HIGH PRESSURE SETTLES INTO THE
UPPER MIDWEST AND GREAT LAKES. CURRENT RADAR DATA SHOWING ANY
LINGERING PCPN ASSOCIATED WITH THE EXITING BOUNDARY...IS NOW
STRETCHED OUT BETWEEN GRR AND DTX AND ALONG THE OHIO RIVER VALLEY.
CURRENT FOG ENHANCED SATELLITE SHOWING A LARGE AREA OF STRATUS OVER
ONTARIO AND NORTHERN LAKE HURON...SPREADING INTO NORTHERN MICHIGAN
UNDER AN INVERSION WHICH HAD DEVELOP OVR THE GREAT LAKES. THE MAIN
FORECAST CONCERN WITH THE CURRENT PATTERN WILL BE CENTERED ON
LINGERING LOW LVL MSTR AND FOG THIS MORNING.

CURRENT SFC OBS ARE SHOWING DEW PTS LINGERING IN THE MID AND UPPER
50S ACRS NRN LOWER...WHILE DEW PTS HAVE FALLEN INTO THE 40S ACROSS
UPPER MICHIGAN AND AREAS JUST NORTH OF LAKE SUPERIOR. SEVERAL
LOCATIONS ACROSS NORTHERN MICHIGAN ARE ALREADY REPORTING FOG...
RANGING FROM 3/4SM NEAR BELLAIRE TO 2SM NEAR CADILLAC. WOULD EXPECT
FOG DEVELOPMENT TO CONTINUE ACROSS THE CWA THRU THE MORNING...A
RESULT OF CALM WINDS AND LINGERING HIGH SFC MSTR. DO NOT EXPECT
WIDESPREAD DENSE FOG OVER ERN UPPER THIS MORNING AS 925MB AND 850MB
STREAM LINES SHOW DRIER DEW PTS FROM CENTRAL CANADA SLOWLY FILTERING
INTO UPPER MICHIGAN EARLY THIS MORNING. HOWEVER WITH SFC DEW
CURRENTLY IN THE MID 50S ACRS NRN LOWER AND SEVERAL LOCATIONS ALREADY
REPORTING VSBYS ONE MILE OR LESS...WILL MENTION AREAS OF DENSE
FOG THIS MORNING SOUTH OF THE STRAITS.

MODEL SOUNDINGS AND MSTR PROGS SHOWING DRIER AIR TO CONTINUE
FILTERING INTO THE GREAT LAKES TODAY AND TONIGHT...AS HIGH PRESSURE
AND UPPER RIDGING COMBINE OVER THE STATE. EXPECT GOOD MIXING ACRS
THE REGION BY EARLY AFTN...MIXING OUT LOW LVL MSTR AND FOG WITH
OVERALL MOSTLY CLEAR SKIES THIS AFTN AND TONIGHT. EXPECT TEMPS WILL
WARM INTO THE LOWER 70S THIS AFTN AS 850MB TEMPS LINGER AROUND
8C...WITH CLEAR SKIES AND CALM WINDS HELPING TEMPS FALL INTO THE
UPPER 40S ACROSS MUCH OF THE REGION TONIGHT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 312 AM EDT SUN AUG 17 2014

...A LITTLE SHOWERY FOR MIDWEEK...

HIGH IMPACT WEATHER POTENTIAL: NOTHING OF NOTE THROUGH EARLY NEXT
WEEKEND. PERHAPS SOME HEAVIER SHOWERS/LOCALIZED HEAVY RAINS FROM A
SLOW MOVING UPPER LOW TUESDAY NIGHT INTO WEDNESDAY NIGHT.

PATTERN SUMMARY: A BRIEF RE-ALIGNMENT OF THE UPPER PATTERN
(FINALLY!) IS FORESEEN THROUGH MUCH OF NEXT WEEK...FEATURING RIDING
UP THROUGH THE GULF OF ALASKA AND A SUBSEQUENT DOWNSTREAM
AMPLIFICATION OF UPPER TROUGHING INTO THE WESTERN CONUS. THAT IS
GOOD NEWS FOR THOSE DESPERATE TO SEE SOME WARMER/MORE HUMID
CONDITIONS TYPICAL OF LATE AUGUST...AS HEIGHTS OVER MUCH OF THE
EASTERN CONUS WILL BUILD WITH TIME. HOWEVER...IN TYPICAL NORTHERN
MICHIGAN FASHION...THERE`S ALWAYS A FLY OR TWO IN THE OINTMENT THAT
WILL GET IN THE WAY OF A STRAIGHTFORWARD FORECAST...WITH THIS
RENDITION`S FEATURE BEING A SLOW-MOVING UPPER WAVE MEANDERING
THROUGH THE GREAT LAKES INTO MIDWEEK. AFTER THAT...DARE I SAY IT
WOULD APPEAR AT LEAST A BRIEF INTERLUDE OF HIGH HEIGHTS IS ON THE
WAY INTO LATE WEEK AND NEXT WEEKEND...AS UPPER RIDGING GETS
SQUEEZED/AMPLIFIED AHEAD OF THE EMERGING WESTERN TROUGH.

A LOOK AT THE DETAILS...

MONDAY-MONDAY NIGHT: LOW LEVEL RIDING WILL WORK INTO EASTERN QUEBEC
AND NEW ENGLAND...AS A UPPER LOW MEANDERS TOWARD THE WESTERN LAKES.
THERE HAS BEEN A DEFINITIVE FASTER TREND NOTED WITH THIS SYSTEM THE
PAST 24 HOURS...SUGGESTING CLOUDS MAY BE ON THE INCREASE LATER
MONDAY...WITH PERHAPS EVEN SOME SHOWERS ARRIVING MONDAY NIGHT IN AN
AXIS OF WEAK BUT PERSISTENT DEVELOPING UPGLIDE. THE AMBIENT AIRMASS
LOOKS AWFULLY DRY ON MONDAY ITSELF TO SUPPORT MORE THAN A SPRINKLE
AT WORST DURING THE LATE DAY...WITH THE BEST CHANCE FOR THAT
PROBABLY UP TOWARD THE STRAITS WHERE 850-700MB THETA-E ADVECTION
WILL BE MAXIMIZED AFTER 21-00Z.

TUESDAY-WEDNESDAY NIGHT: MUCH BETTER CHANCES FOR SHOWERS SHOULD
ARRIVE TUESDAY INTO TUESDAY NIGHT AS SAID WESTERN LAKES UPPER LOW
VERY SLOWLY WORKS OVERHEAD. BROAD/WEAK BUT PREVALENT WARM ADVECTION
ASCENT SHOULD HAVE LITTLE TROUBLE DELIVERING A ROUND OF SHOWERS FOR
MANY AREAS. AS MENTIONED YESTERDAY...THERE COULD WELL BE A SNEAKY
HEAVIER RAIN ISSUE SOMEWHERE DURING THIS TIME GIVEN VERY WEAK
STEERING FLOW (LESS THAN 10 KNOTS) COMBINED WITH A HIGH PWAT/HIGH
FREEZING LEVEL ENVIRONMENT. A PERUSAL OF FORECAST RAOBS TUESDAY INTO
TUESDAY NIGHT GIVE FURTHER HINTS...WITH SKINNY CAPE PROFILE OF
AROUND 700 J/KG SPREAD OVER A DEEP LAYER INDICATIVE OF WEAK BUT
PERSISTENT UPDRAFTS THAT SHOULD HAVE GOOD PRECIP EFFICIENCY GIVEN
FREEZING/WET BULB ZERO LEVELS UP AROUND 13KFT. THROW IN THE HISTORY
OF HEAVY RAINS WITH THIS SYSTEM OVER THE NORTHERN ROCKIES AND PLAINS
RECENTLY (SOME 6+" AMOUNTS OVER THE PAST 36 HOURS!) AND AN HWO
MENTION IS NO DOUBT WARRANTED.

PRECIP COVERAGE WILL LIKELY WANE LATE TUESDAY NIGHT INTO WEDNESDAY
AS WEAK DOWNGLIDE SETS IN...BUT CAN BY NO MEANS RULE OUT SOME
DIURNAL REGENERATION WEDNESDAY AFTERNOON GIVEN THE REMAINING MOIST
AND WEAKLY UNSTABLE ENVIRONMENT. ALSO...THERE IS A NOTABLE SLOWER
TREND WITH ECMWF GUIDANCE...HOLDING BACK THE UPPER LOW SQUARELY
OVERHEAD RIGHT ON THROUGH WEDNESDAY EVENING...SUGGESTIVE THAT SAID
DOWNWARD MOMENTUM MAY BE DELAYED. GIVEN THE BETTER DOWNSTREAM
BLOCKING OVER NEW ENGLAND...THIS LATTER IDEA MAY HAVE SOME MERIT AND
GOING POPS WILL CERTAINLY REMAIN. TEMPERATURES THROUGHOUT THE
MIDWEEK PERIOD ARE TRICKY. JUST LIKE WE HAVE OBSERVED SO MAY TIMES
THIS SUMMER...WE COULD BE LOOKING AT READINGS STUNTED HEAVILY BY
ONGOING PRECIP ON TUESDAY...AND BASED ON RECENT HISTORY...FEEL THE
NEED TO LOWER GOING READINGS BY A FEW DEGREES. WEDNESDAY MAY BE A
DIFFERENT STORY WITH PERHAPS SOME SUNSHINE THROWN IN AT TIMES.

THURSDAY-SATURDAY: THE LOWER CONFIDENCE PORTION OF THE FORECAST AS
NORTHERN MICHIGAN GETS SQUEEZED BETWEEN RISING HEIGHTS FROM THE
PLAINS INTO THE WESTERN LAKES...AND BROADER UPPER TROUGHING INTO NEW
ENGLAND. CAN`T AT ALL RULE OUT SOME ADDITIONAL SHOWERS ON THURSDAY
IN THAT "SQUEEZE PLAY" AS BETTER BOUNDARY LAYER MOISTURE REMAINS
INTACT. FRIDAY/SATURDAY LOOKING A LITTLE BETTER AS PERSISTENT
EASTERLY LOW LEVEL FLOW HELPS RECYCLE DRIER AIR BACK INTO THE AREA
BUT HONESTLY...ANYTHING AFTER THURSDAY NIGHT IS VERY LOW CONFIDENCE
AS MEDIUM RANGE GUIDANCE CONTINUES TO STRUGGLE IN ANOTHER AMPLIFYING
PATTERN OVER THE COUNTRY. WILL MAINTAIN THE CURRENT DRY FORECAST FOR
THE MOMENT...BUT ANY FURTHER SLOWDOWN OF THE UPPER LOW JUST TO OUR
EAST COULD PUT THAT IN JEOPARDY. TEMPS AT LEAST LOOK TO GET A BOOST
BACK TOWARD OR EVEN ABOVE (GASP!) LATE AUGUST NORMS BY FRIDAY...
RISING WELL INTO THE 70S AND PERHAPS EVEN 80S PENDING THE FINAL
EVOLUTION OF CLOUD COVER.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 640 AM EDT SUN AUG 17 2014

FAIRLY UNIFORM IFR STRATUS CLOUD DECK HAS MOVED OVER NRN MI TAF
SITES THIS MORNING. HOWEVER...GOOD MIXING EXPECTED LATER THIS
AFTERNOON WILL HELP ERODE THE LOW CLOUDS ACRS NRN MI. VSBY WILL
VARY GREATLY WITH LOCATION THIS MORNING...A RESULT OF ISOLATED
HEAVY RAINS YESTERDAY AND SFC DEW PTS LINGERING IN THE 50S. IFR CIGS
AND VSBY THIS MORNING ARE BOTH EXPECTED TO IMPROVE TO VFR LATER
THIS AFTERNOON AS DRIER AIR MIXES INTO THE REGION.

&&

.MARINE...
ISSUED AT 312 AM EDT SUN AUG 17 2014

WINDS AND WAVES WILL BE BELOW SCA CRITERIA TODAY THROUGH TUESDAY
ACROSS NORTHERN GREAT LAKES NEARSHORE WATERS...AS SFC AND UPPER
RIDGING COMBINE OVER THE GREAT LAKES. THE NEXT CHANCE OF RAIN WILL
BE TUESDAY...AS A NORTHERN PLAINS STORM SYSTEM MOVES INTO THE GREAT
LAKES.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

SYNOPSIS...LAWRENCE
SHORT TERM...SR
LONG TERM...LAWRENCE
AVIATION...SR
MARINE...SR






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