000
FXUS63 KAPX 150650
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
250 AM EDT SAT JUN 15 2013

.SYNOPSIS...
ISSUED AT 250 AM EDT SAT JUN 15 2013

CLOUDS WILL INCREASE TODAY AS A SERIES OF UPPER LEVEL DISTURBANCES
BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO NORTHERN MICHIGAN
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH THE WEEKEND AND INTO
EARLY NEXT WORK WEEK.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 250 AM EDT SAT JUN 15 2013

FIRST OF ALL...HATS OFF TO OLD MOTHER NATURE...DELIVERING ONE OF THE
FINER SUMMER DAYS YOU WILL SEE AROUND THESE PARTS YESTERDAY. DRY
AIRMASS RESPONSIBLE FOR SUCH FANTASTIC WEATHER STILL FIRMLY IN
CONTROL AT THIS EARLY HOUR...WITH EXPANSIVE SURFACE HIGH PRESSURE
EXTENDING FROM THE NORTHERN LAKES RIGHT DOWN INTO THE SOUTHEASTERN
STATES. 00Z RAOB PWAT ANALYSIS CONFIRMS SUCH...WITH CP AIRMASS
BRINGING SUB ONE INCH PWAT VALUES ACROSS THIS SAME REGION (RATHER
IMPRESSIVE FOR THIS TIME OF YEAR). UNFORTUNATELY...ONE DOES NOT HAVE
TO VENTURE TOO FAR WEST FOR SOME INCLEMENT WEATHER. BACKSIDE RETURN
FLOW ALREADY AMPING UP ACROSS THE WESTERN LAKES...WITH REAL-TIME OBS
AND HIGH RES RUC ANALYSIS SHOWING ELEVATED MOISTURE PLUME ALREADY
PUNCHING THROUGH WISCONSIN AND WESTERN UPPER MICHIGAN. LEADING
MOISTURE CONVERGENCE AXIS AND SUBTLE WAVE PIVOTING THROUGH BROADER
UPSTREAM RIDGING MANAGED TO KICK OFF SOME EVENING SHOWERS AND STORMS
TO OUR NORTHWEST...ALTHOUGH THESE HAVE LARGELY DIED OUT AS THEY
APPROACH OVERHEAD DEEP LAYER DRY WEDGE. THEME OF THIS SUMMER
CONTINUES...WITH THE MOST PROMINENT AREA OF SHOWERS AND STORMS
REMAINING SAFELY TO OUR SOUTHWEST WHERE NOCTURNALLY CHARGED LOW
LEVEL JET FORCED MASS CONVERGENCE AND DEEP INSTABILITY ARE BETTER
JUXTAPOSED. RADAR AND SATELLITE TRENDS BOTH SUGGEST THIS SHOULD
REMAIN THE CASE RIGHT THROUGH THE EARLY MORNING HOURS...LEAVING
MOSTLY DRY CONDITIONS ACROSS OUR AREA THROUGH AT LEAST THE FIRST
HALF OF THE MORNING. SHORT TERM FORECAST CONCERNS CENTER ON POSSIBLE
ADDITIONAL SHOWER AND STORM DEVELOPMENT TODAY AND TONIGHT.

GOING TO BE AWFULLY HARD TO BEAT YESTERDAY...AND......WE WON`T.
THAT SAID...UPSTREAM TRENDS AND PATTERN RECOGNITION SUPPORTS A
NOT-TO-SHABBY START TO THE WEEKEND. REMAIN LARGELY UNENTHUSED WITH
RAIN CHANCES TODAY...DESPITE STAGE RIGHT DEPARTURE OF CURRENT
SURFACE HIGH. UPSTREAM MID LEVEL RIDGING REPLACES ITS SURFACE
LIKENESS...ALTHOUGH DEAMPLIFYING AS IT DOES SO WITH ENERGY CUTTING
ACROSS SOUTHERN CANADA. UPPER LEVEL FORCING ARRIVES LATE VIA RER
UPPER JET DYNAMICS...MOST OF WHICH HOLDS OFF UNTIL THE OVERNIGHT
HOURS. PER THE USUAL...GUIDANCE JUST SEEMS MUCH TOO AGGRESSIVE
DRIVING LOW LEVEL MOISTURE THIS FAR NORTH...ESPECIALLY GIVEN
ANTECEDENT DRY CONDITIONS AND PROPENSITY FOR MOISTURE STEALING
CONVECTION TO CONTINUE TO FIRE WELL TO OUR SOUTHWEST. MODIFYING
MODEL SUGGESTED SOUNDINGS FOR SUCH SHOWS SIGNIFICANT MID LEVEL CAP
UNTIL VERY LATE...AND LITTLE...IF ANY ML CAPE DEVELOPMENT. CORE OF
MORE IMPRESSIVE MID LEVEL LAPSE RATES REMAINS JUST UPSTREAM ACROSS
WISCONSIN. THETA-E RIDGING DOES ADVANCE EAST WITH TIME....CROSSING
OUR AREA LATE MORNING THROUGH THE AFTERNOON. EVEN THIS...HOWEVER...
WILL BE LOSING DEFINITION WITH TIME. NO DOUBT CLOUDS WILL BE ON THE
INCREASE AS UPSTREAM MID LEVEL MOISTURE PLUME ADVANCES EAST...BUT
GIVEN ALL THE ABOVE...THE PROSPECTS FOR ANY MEANINGFUL RAINS ARE
MUCH LESS THAN IDEAL. SUPPOSE A SPRINKLE/VERY LIGHT SHOWER IS
PLAUSIBLE ALONG THETA-E GRADIENT OR FROM WHAT`S EVER LEFT OF
UPSTREAM ACTIVITY. TEMPTED TO PULL POPS ALTOGETHER...BUT GIVEN SOME
LINGERING UNCERTAINTY...WILL JUST SIMPLY MAINTAIN INHERITED LOW
CHANCE MENTION. DESPITE CLOUDS...THERMAL PROFILES SUPPORT A RATHER
MILD DAY...WITH HIGHS WELL INTO THE 70S ACROSS MOST AREAS. LIGHT
PRESSURE GRADIENT SUPPORTS LATE MORNING AND AFTERNOON LAKE BREEZE
DEVELOPMENT...KEEPING SHORELINE AREAS A FEW DEGREES COOLER.

THINGS TRY TO CONGEAL TO BRING BETTER RAIN CHANCES TONIGHT...WITH
SOMEWHAT DEEPER LOW LEVEL MOISTURE OVERTOPPED BY UPPER JET DYNAMICS.
NOTHING OVERLY IMPRESSIVE THROUGH THE MID LEVELS...WITH PERHAPS A
CONVECTIVELY AUGMENTED VORT LOBE/SUBTLE WAVE RACING EAST ACROSS THE
SOUTHERN THIRD OF THE AREA. PATTERN RECOGNITION CONTINUES TO SUPPORT
SOUTHERN LAKES/NORTHERN OHIO VALLEY MCS DEVELOPMENT ON NOSE OF
STRONGER LOW LEVEL JET. SOME GUIDANCE SEEMS OVERLY AGGRESSIVE
DRIVING CONVECTIVE DEVELOPMENT NORTH...ESPECIALLY THE 00Z GFS AND
12Z ECMWF. DEEP LAYER FLOW SIMPLY DOES NOT BACK ENOUGH TO SUPPORT
THESE NORTH BASED TRENDS. CONVECTIVE EVOLUTION TODAY WILL HAVE
PLENTY TO SAY ON OVERALL MASS FIELDS...BUT LARGE SCALE PATTERN FULLY
SUPPORTS A MORE SOUTH BASED PASSAGE TO ANY MCS TONIGHT...WITH JUST
SOME LIGHTER ACTIVITY THIS FAR NORTH. WILL TREND POPS AS SUCH...BUT
STILL LEAVE PLENTY OF OPPORTUNITY FOR FUTURE ADJUSTMENTS BASED ON
THIS AFTERNOONS UPSTREAM TRENDS. A MILD NIGHT...WITH LOWS IN THE 50S
AND LOWER 60S.

&&

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 250 AM EDT SAT JUN 15 2013

SUNDAY AND MONDAY...A WEAK AREA OF LOW PRESSURE WILL SLIDE EAST THRU
MICHIGAN EARLY SUNDAY MORNING. THIS LOW WILL GRADUALLY MERGE WITH
ANOTHER NRN STREAM LOW DROPPING SE INTO MICHIGAN SUNDAY AFTERNOON
AND EVENING. A COLD FRONT ASSOCIATED WITH THE SECOND LOW PRESSURE
SYSTEM WILL DROP INTO NRN MICHIGAN SUNDAY NIGHT...AND WILL THEN
SWEEP THRU LWR MICHIGAN ON MONDAY. LATEST NAM APPEARS TO BE TOO FAST
WITH THE PASSAGE OF THIS FRONT CONSIDERING THE FRONT BECOMES
ORIENTED WEST TO EAST ALONG THE UPPER LEVEL FLOW ONCE IT REACHES
UPPER MICHIGAN. ECMWF PROVIDES A SLOWER AND THUS MORE REASONABLE
SOLUTION...AND WILL LEAN IN THIS DIRECTION. CHANCE OF SHOWERS/STORMS
WILL LINGER INTO SUNDAY MORNING FOR MUCH OF OUR CWA AS THE INITIAL
SURFACE LOW EXITS LWR MICHIGAN. DIURNAL INSTABILITY COMBINED WITH
WEAK LAKE BREEZE BOUNDARIES AND LINGERING LOW LEVEL MOISTURE TO
PROVIDE SMALL CHANCES OF SHOWERS AND STORMS FOR ERN UPR AND NE LWR
MICHIGAN SUNDAY AFTERNOON. SECONDARY SURFACE LOW AND ASSOCIATED COLD
FRONT WILL DROP INTO ERN UPR AND FAR NRN LWR MICHIGAN SUNDAY
AFTERNOON/EVENING...PROVIDING ADDITIONAL FOCUS FOR CONVECTIVE
DEVELOPMENT TO PERSIST THRU THE NIGHT ACROSS LOCATIONS ALONG AND
NORTH OF M-32. BY MONDAY...THE SLOW-MOVING COLD FRONT WILL DROP THRU
THE REST OF OUR CWA...RESULTING IN CONTINUED CONVECTIVE DEVELOPMENT
THRU THE DAY. CHANCES OF SHOWERS AND STORMS WILL COME TO AN END THRU
MONDAY NIGHT AS THE COLD FRONT EXITS LWR MICHIGAN.

TUESDAY THRU FRIDAY...STRONG CANADIAN HIGH PRESSURE...SUBSIDENCE AND
DRY AIR WILL BUILD INTO THE GREAT LAKES TUESDAY INTO WEDNESDAY
BEHIND THE DEPARTING COLD FRONT. DRY WEATHER IS EXPECTED THRU THIS
TIME PERIOD...WITH TEMPS SEVERAL DEGREES BELOW NORMAL THANKS TO CAA.
WEAK AREA OF LOW PRESSURE WILL SLOWLY TRACK THRU ONTARIO AND INTO
QUEBEC WEDNESDAY NIGHT THRU FRIDAY...DRAGGING THE SRN END OF A WEAK
FRONT THRU NRN MICHIGAN. BOTH MOISTURE AND LIFT WILL BE LIMITED WITH
THIS WEAK FEATURE...BUT WILL INTRODUCE SMALL PRECIP CHANCES INTO THE
FORECAST FOR THIS TIMEFRAME AS THIS FRONT PASSES THRU THE REGION.
TEMPS WILL REBOUND TO NEAR NORMAL IN WEAK WAA AHEAD OF THIS FRONT.
INITIAL LOOK FOR NEXT WEEKEND SUGGESTS MAINLY DRY WEATHER WITH NEAR
NORMAL TEMPS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 135 AM EDT SAT JUN 15 2013

VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THIS TAF PERIOD.
INCREASING MOISTURE MAY BRING A FEW LIGHT SHOWERS LATER THIS
AFTERNOON. STRONGER FORCING ARRIVES TONIGHT...ALTHOUGH TRENDS
SUPPORT BETTER SHOWER AND STORM POTENTIAL REMAINING OFF TO THE
SOUTH OF THE TAF SITES. LOW LEVEL DRY AIR LOOKS TO KEEP CIGS
WITHIN VFR CATEGORY. WILL NOT INCLUDE THUNDER MENTION UNTIL
UPSTREAM CONVECTIVE TRENDS BECOME ESTABLISHED. LIGHT WINDS...WITH
LOCAL LAKE BREEZE DEVELOPMENT THIS AFTERNOON...WILL CONTINUE.


&&

.MARINE...
ISSUED AT 250 AM EDT SAT JUN 15 2013

LIGHT WINDS CONTINUE...WITH LOCAL LAKE BREEZE DEVELOPMENT
THIS AFTERNOON...ESPECIALLY OFF LAKE HURON. WEAK SURFACE TROUGH
PASSES THROUGH THE REGION LATE TONIGHT INTO EARLY SUNDAY...VEERING
SOUTHWEST FLOW TO WESTERLY. MARINE FOG EXPECTED TO DEVELOP LATER
TONIGHT INTO SUNDAY AS LOW LEVEL MOISTURE ADVECTION STRENGTHENS.
SHOWERS AND STORMS POSSIBLE TONIGHT...ALTHOUGH STRONGEST ACTIVITY
EXPECTED TO REMAIN ACROSS THE SOUTHERN LAKES. EARLY INDICATIONS ARE
FOR MAINLY LIGHT WINDS TO CONTINUE RIGHT THROUGH MUCH OF NEXT WORK
WEEK.

&&

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

&&

$$

SYNOPSIS...MR
SHORT TERM...MB
LONG TERM...MR
AVIATION...MB
MARINE...MB