Area Forecast Discussion
Issued by NWS Gaylord, MI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KAPX 310347
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1147 PM EDT SAT AUG 30 2014

.SYNOPSIS...
ISSUED AT 358 PM EDT SAT AUG 30 2014

SLOW MOVING LOW PRESSURE WILL MEANDER THROUGH NORTHERN MICHIGAN
TODAY...DELIVERING ADDITIONAL SHOWERS AND THUNDERSTORMS. CONDITIONS
WILL BRIEFLY DRY OUT FOR SUNDAY AS HIGH PRESSURE ARRIVES...WITH
ANOTHER PERIOD OF SHOWERS AND STORMS ANTICIPATED FOR LABOR DAY AHEAD
OF AN APPROACHING COLD FRONT. DRY AND MORE SEASONABLE CONDITIONS
WILL RETURN BEHIND THAT FRONT FOR THE FIRST PART OF THE WORK WEEK.

&&

.UPDATE...
ISSUED AT 943 PM EDT SAT AUG 30 2014

1006MB SURFACE LOW CENTERED OVER EASTERN UPPER MI. NW FLOW/COLD
ADVECTION UNDERWAY IN WESTERN CHIP/MACK COUNTIES...AND JUST
REACHING THE NW LOWER MI COAST. AS IS TYPICAL...FIRST PUSH OF
COOLER AIR INTO A VERY MOIST LOW-LEVEL AIRMASS IS RESULTING IN
RAPID DEVELOPMENT/EXPANSION OF LOW CLOUDS/STRATUS. THE MOST
WIDESPREAD PRECIP IS OFF TO THE EAST...BUT DEEP CYCLONIC FLOW IS
STILL CONTRIBUTING TO SPOTTY SHRA (MOST EVIDENT IN NW LOWER MI).
THIS WILL LIKELY MORPH/DIMINISH INTO JUST DRIZZLE BY THE LATE
OVERNIGHT...THOUGH THE LOW CLOUDS SHOULD REMAIN EXPANSIVE ACROSS
THE AREA INTO SATURDAY.

&&

.SHORT TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 358 PM EDT SAT AUG 30 2014

POTENT SHORT WAVE NOW CROSSING NORTHEAST OUT OF WISCONSIN ACROSS
CENTRAL AND NORTHERN LAKE MICHIGAN WITH A SMALL 90 KNOT JET CORE
PUNCHING INTO SRN LOWER MICHIGAN. ASSOCIATED SFC LOW NOW ADVANCING
INTO UPPER MICHIGAN ALONG PSEUDO-STALLED FRONT THAT STRETCHES UP
JUST INTO EASTERN UPPER MICHIGAN. AHEAD OF THIS WAVE...AIRMASS
ACROSS LOWER MICHIGAN IS WARM AND MOIST WITH TEMPS PUSHING 80 AND
DEWPOINTS IN THE HIGH 60S TO AROUND 70...PRETTY GOOD FOR NRN
MICHIGAN. SPC MESO-ANALYSIS AND 18Z APX RAOB REVEALING AROUND 500
J/KG OF SKINNY MLCAPE...DISAPPOINTING GIVEN THE SFC TEMPS/
DEWPOINTS...BUT OWING TO RATHER PALTRY LAPSE RATES ABOVE THE SFC
BASED MIXED LAYER...WHICH ONLY EXTENDS TO ABOUT 850 MB. THUS...
DESPITE INCREASING FORCING ACROSS THE REGION FROM APPROACHING SHORT
WAVE...CONVECTIVE DEVELOPMENT THUS FAR HAS BEEN LESS THAN
IMPRESSIVE...ALTHOUGH UPDRAFTS THAT ARE OUT THERE HAVE SHOWN
ORGANIZATION AND WEAK ROTATION DESPITE THEIR SIZE.

TONIGHT...SHORT WAVE WILL CONTINUE TO TRACK UP THROUGH NRN LAKE
MICHIGAN INTO EASTERN UPPER MICHIGAN BY EARLY EVENING WITH THE
STRONGEST UPPER SUPPORT SWINGING THROUGH THE REGION THROUGH THAT
TIME. ONGOING CONVECTION WILL CONTINUE TO GROW UPSCALE LATE THIS
AFTERNOON THROUGH EARLY EVENING...ALTHOUGH SOMEWHAT PALTRY
INSTABILITY MAY KEEP COVERAGE/OVERALL ORGANIZED SEVERE WEATHER
THROTTLED. NONETHELESS...ATMOSPHERE IS CONDUCIVE TO ORGANIZED
ROTATING UPDRAFTS AS WE/VE SEEN WITH A FEW STORMS THUS FAR AND A
LOWER END SEVERE WEATHER THREAT WILL PERSIST INTO THE EARLY EVENING
HOURS.

THEREAFTER...COLD FRONT SLOWLY SAGS INTO THE REGION LATER THIS
EVENING AND OVERNIGHT. MAIN PRECIP THREAT WINDS DOWN. BUT SECONDARY
SHORT WAVE AND BATCH OF BETTER MOISTURE WILL SLIDE THROUGH THE
REGION LATE EVENING AND OVERNIGHT AND KEEP A LOW END CHANCE FOR
SHOWERS/DRIZZLE GOING THROUGH EARLY SUNDAY MORNING.

.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 358 PM EDT SAT AUG 30 2014

...ACTIVE WEATHER PATTERN...

HIGH IMPACT WEATHER POTENTIAL: POSSIBLE STRONG TO SEVERE
THUNDERSTORMS MONDAY.

A FAIRLY FAST FLOW ALOFT WILL BE OVER OR JUST TO OUR NORTH OVER THE
COMING DAYS WITH UPPER LEVEL DISTURBANCES/SURFACE FRONTS MOVING
ACROSS THE REGION. THIS WILL RESULT IN A FAIRLY ACTIVE WEATHER
PATTERN ACROSS NORTHERN MICHIGAN WITH AT LEAST TWO MORE GOOD CHANCES
FOR ROUNDS OF SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL BE
CHANGEABLE THROUGH THE EXTENDED PERIOD BUT ARE EXPECTED TO BE ABOVE
TYPICAL "NORMALS". THE MAIN LONG TERM FORECAST CONCERNS CENTER
AROUND LOW CLOUD POTENTIAL SUNDAY...POPS AND THE POTENTIAL FOR
SEVERE WEATHER MONDAY THEN POPS AGAIN FOR THURSDAY INTO FRIDAY.

SUNDAY...MODEL SOUNDINGS/CROSS SECTIONS SHOW ABUNDANT MOISTURE
TRAPPED BELOW A SHALLOW INVERSION BEHIND DEPARTING COLD FRONT. HIGH
PRESSURE/DRIER AIR ADVECTING IN FROM THE WEST SHOULD SLOWLY ERODE
STRATUS DECK BY EARLY AFTERNOON. TEMPERATURES ARE A BIT TRICKY DUE
TO UNCERTAINTY OVER EXTENT/TIMING OF LOW CLOUDS BUT HAVE HIGHS
GENERALLY RANGING THROUGH THE 70S (COOLEST NORTHWEST AND WARMEST
SOUTHEAST).

SUNDAY NIGHT...WEAK HIGH PRESSURE MOVES ACROSS THE REGION IN THE
EVENING THEN OFF TO OUR EAST OVERNIGHT LEADING TO A MORE MOIST
SOUTHERLY FLOW. SO EXPECT CLEAR TO PARTLY CLOUDY SKIES AND MILD
TEMPERATES WITH LOWS IN THE MIDDLE 50S TO LOWER 60S.

MONDAY...THE NEXT UPPER LEVEL TROUGH/SURFACE COLD FRONT APPROACH
FROM THE WEST. WIND FIELDS ARE PRETTY IMPRESSIVE (0-6KM BULK SHEAR
35 TO 45 KNOTS) SO THIS IN COMBINATION WITH STRONG DAYTIME HEATING
(HIGHS EXPECTED TO BE IN THE LOWER AND MIDDLE 80S) WE THERE IS
POTENTIAL TO DEVELOP SOME STRONG TO SEVERE THUNDERSTORMS.

TUESDAY...COOLER WITH NEARLY ZONAL FLOW ALOFT AND WEAK SURFACE HIGH
PRESSURE CENTERED OFF TO OUR SOUTH. SO EXPECT PARTLY CLOUDY SKIES
AND HIGHS IN THE LOWER AND MIDDLE 70S.

WEDNESDAY THROUGH SATURDAY...RISING HEIGHTS AND ALONG WITH ANOTHER
WARMING TREND FOR WEDNESDAY INTO THURSDAY. ANOTHER FRONT IS THEN DUE
IN LATER THURSDAY OR THURSDAY NIGHT LEADING TO MORE CHANCES FOR
SHOWERS AND THUNDERSTORMS. HIGHS RANGING FROM THE MIDDLE 70S TO
LOWER 80S WEDNESDAY THEN THE MIDDLE 70S TO MIDDLE 80S THURSDAY.
THERE IS QUITE A BIT OF UNCERTAINTY OVER THE TIMING OF WHEN THE
FRONT ACTUALLY CLEARS THE AREA FRIDAY INTO SATURDAY BUT GENERALLY
WENT WITH THE FASTER ECMWF TIMING WHICH BUILDS HIGH PRESSURE IN FROM
THE WEST. HIGHS FRIDAY MAINLY IN THE 70S THEN THE MIDDLE 60S TO
LOWER 70S SATURDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1147 PM EDT SAT AUG 30 2014

IFR CIGS INTO SUNDAY MORNING.

LOW PRESSURE MOVING EAST OF THE SAULT...AND WILL CONTINUE EAST TO
SW QUEBEC BY SUNDAY AFTERNOON. AN ASSOCIATED COLD FRONT IS
CROSSING NORTHERN LOWER MI.  STRATUS WILL RAPIDLY EXPAND BEHIND
THIS FRONT...AND IFR TO LIFR CIGS ARE EXPECTED FOR ALL TAF SITES
FOR MUCH OF THE NIGHT AND MORNING. GRADUAL IMPROVEMENT TO VFR WILL
BEGIN LATE IN THE MORNING.

LIGHT W TO NW WINDS.

&&

.MARINE...
ISSUED AT 358 PM EDT SAT AUG 30 2014

GUSTY SOUTHERLY WINDS OUT THERE THIS AFTERNOON WILL SLOWLY VEER
WESTERLY TONIGHT...AS AN ILL-DEFINED FRONT SAGS DOWN THROUGH THE
REGION. BUT WINDS/WAVES ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
CRITERIA THROUGH TONIGHT.

SUNDAY...BETTER WEATHER AS WEAKISH HIGH PRESSURE AND SLIGHTLY
DRIER AIR BUILD ACROSS THE REGION BUT WINDS BACK SOUTHERLY AND
INCREASE AGAIN SUNDAY NIGHT GOING INTO MONDAY AS ANOTHER SYSTEM
APPROACHES THE REGION. GUSTY WINDS ON MONDAY COULD BE ENOUGH TO
WARRANT SMALL CRAFT ADVISORIES.


&&

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

&&

$$

UPDATE...JZ
SYNOPSIS...MG
SHORT TERM...ADAM
LONG TERM...AS
AVIATION...JZ
MARINE...ADAM





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.