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000
FXUS63 KAPX 310805
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
405 AM EDT THU JUL 31 2014

.SYNOPSIS...
ISSUED AT 403 AM EDT THU JUL 31 2014

WEAK UPPER LEVEL DISTURBANCES ROTATING ACROSS THE REGION WILL
CONTINUE TO BRING PERIODIC CHANCES FOR SHOWERS THROUGH SATURDAY
...ESPECIALLY DURING THE AFTERNOON HOURS AND MAINLY ACROSS NORTHEAST
LOWER MICHIGAN. DRY WEATHER RETURNS TO END THE WEEKEND...WITH THE
THREAT FOR A FEW MORE SHOWERS TO START NEXT WORK WEEK. TEMPERATURES
WILL RETURN TO MUCH MORE SEASONAL LEVELS BY FRIDAY AND ON INTO THE
EXTENDED.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 403 AM EDT THU JUL 31 2014

...A SIMILAR DAY WITH A FEW MORE SHOWERS...

IMPACTS: NONE.

CURRENT WEATHER AND SYNOPTIC PATTERN:

DEEP CLOSED UPPER LOW STILL CIRCLING NEAR JAMES BAY WITH SEVERAL
VORTICITY MAXIMA ROTATING AROUND THE GYRE. ONE OF THE STRONGER VORT
MAXIMA WAS PUSHING EAST OF US EARLY THIS MORNING...ALONG WITH THE
ASSOCIATED SFC TROUGH. A WEAKER WAVE...ONLY NOTED ON SOME OF THE
HIGHER RESOLUTION DATA IS QUICKLY FOLLOWING...AND DRIVING THE
LAST VESTIGES OF LIGHT SHOWERS OUT OF NE LOWER. FURTHER UPSTREAM IN
THE NNW FLOW ALOFT...A MUCH WEAKER VORT MAX IS DROPPING SE FROM SW
ONTARIO...AND IS ASSOCIATED WITH JUST ANOTHER IN A SERIES OF RECENT
SFC TROUGHS. THIS SFC TROUGH IS ALIGNED FROM JAMES BAY THROUGH
CENTRAL LAKE SUPERIOR...WITH MQT/APX VAD WIND PROFILES SHOWING
BACKING LOW LEVEL WINDS. THERE WERE SOME SHOWERS ASSOCIATED WITH
THESE FEATURES YESTERDAY AFTERNOON...WITH NO THUNDER...AS LAPSE
RATES WERE LESS WITHOUT A STRONGER WAVE ALOFT. ALSO...MORE
WIDESPREAD AND DEEPER MOISTURE IS SEEN ACROSS ONTARIO...WORKING
SOUTHWARD INTO EASTERN UPPER. THE BETTER LOW LEVEL WINDS/MOISTURE
AND STEEPER LAPSE RATES/INSTABILITY GRADIENT RESIDE WELL WEST ACROSS
MN/WISCONSIN.

SYNOPTIC PATTERN/WEATHER EVOLUTION:

LOW TO MID LEVEL NORTHERLY FLOW WILL CONTINUE TO WRAP DEEPER
MOISTURE FROM ONTARIO DOWN AND ACROSS EASTERN UPPER THIS MORNING
INTO EARLY AFTERNOON. THIS MAY KEEP OVERALL BL HEATING AND RESULTANT
INSTABILITY AT BAY. LESS CLOUDS ACROSS NRN LOWER AND SLIGHTLY WARMER
LOW LEVEL TEMP REGIME THAN YESTERDAY. BL MOISTURE REMAINS
UNIMPRESSIVE...BUT MODIFICATION OF FCST BFR SOUNDINGS DO REVEAL A
FEW HUNDRED J/KG SNEAKING BY A WEAK CAP AT 650MB. FROM A FORCING
PERSPECTIVE...AFOREMENTIONED WEAKER VORT MAX AND SFC TROUGH DO TRY
AND ROTATE SOUTHWARD INTO EASTERN UPPER THIS AFTERNOON...AND IS
QUITE WEAK. THOUGH WINDS ARE LIGHT AND DIFFICULT TO DISCERN THE SFC
TROUGH...IT APPEARS TO PUSH THROUGH NRN LOWER THIS EVENING/TONIGHT.
LOW LEVEL WINDS ARE LIGHT...AND LAKE BREEZES TODAY WILL DISRUPT LOW
LEVEL CONVERGENCE WITH THE TROUGH...BUT ALSO CREATE ANOTHER DAY OF
LAKE BREEZE CONVERGENCE ACROSS INTERIOR EASTERN UPPER AND NE LOWER.
PUT ALL THIS TOGETHER...AND BELIEVE THAT OVERALL SHOWER ACTIVITY
WILL BE LESS THAN YESTERDAY. ISOLATED LIGHT SHOWERS ACROSS INTERIOR
EASTERN UPPER...WITH ISOLATED TO SCATTERED ACTIVITY EAST OF I-75 AND
MOST COMMON ACROSS FAR NE LOWER. THE PASSING OF THE MID LEVEL TROUGH
AND WEAK SFC TROUGH TONIGHT...RESULTING IN A FEW ROAMING SHOWERS IN
NRN LOWER.

HIGH TEMPERATURES NEAR 70F IN EASTERN UPPER WITH THE LOWER HALF OF
THE 70S IN NRN LOWER. LOWS TONIGHT AGAIN IN THE UPPER 40S AND LOWER
50S.

&&

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 403 AM EDT THU JUL 31 2014

...TEMPERATURES MUCH CLOSER TO NORMAL WITH A FEW LINGERING SHOWER
CHANCES...

HIGH IMPACT WEATHER POTENTIAL: MINIMAL.

PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: CURRENT UNSEASONABLY DEEP
EAST NOAM TROUGHING WILL BEGIN TO RELAX SOME HEADING INTO THE END OF
THE WEEK...LEADING TO A MUCH LESS AMPLIFIED VERSION OF ITSELF
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THAT SAID...SOME
SEMBLANCE OF GREAT LAKES TROUGHING WILL REMAIN...ENSURING NO REAL
SUSTAINED SUMMER HEAT ANYTIME IN THE FORESEEABLE FUTURE. STILL A FEW
VORT LOBES/LOW AMP SHORTWAVES TO PASS THROUGH THIS DEAMPLIFYING
TROUGH...AND WHEN COMBINED WITH THE DIURNAL INSTABILITY CYCLE/LAKE
INDUCED CONVERGENCE AXES...CONTINUES TO SUPPORT MAINLY AFTERNOON
SHOWER POTENTIAL BOTH FRIDAY AND SATURDAY. NEXT WAVE LOOKS TO ARRIVE
EARLY NEXT WEEK...BRINGING ADDITIONAL SHOWER CHANCES.

PRIMARY FORECAST CONCERNS/CHALLENGES: TEMPERATURE AND CLOUD TRENDS
THROUGHOUT. ACCESSING MAINLY AFTERNOON SHOWER POTENTIAL FOR THE
REMAINDER OF THIS WEEK. EARLY NEXT WEEK SHOWER CHANCES WILL ALSO
NEED ADDRESSING.

DETAILS: THOUGHT PROCESS HAS NOT CHANGED MUCH AT ALL FOR FRIDAY
THROUGH THE WEEKEND. PATTERN RECOGNITION CONTINUES TO SUPPORT
MAINLY AFTERNOON SHOWER DEVELOPMENT AS SAID WAVES INTERACT WITH THE
"PEAK" OF THE DAYTIME HEATING CYCLE. LOW LEVEL CONVERGENCE
BULLSEYE`S WILL BE THERE FOR A FOCUSING MECHANISM...SPECIFICALLY IN
THE FORM OF MAINLY LAKE HURON INDUCED LAKE BREEZES. LACK OF FORCING
AND RATHER LIMITED LOWER LEVEL MOISTURE (DEWPOINTS REMAINING MOSTLY
IN THE 50S) SHOULD KEEP SHOWER COVERAGE SCATTERED...AND PRECLUDE
MUCH OF A THUNDER THREAT. PATTERN FULLY SUPPORTS A STRONG APPROACH
TO TRADITIONAL NORTHERN MICHIGAN WARM-SEASON CONVECTIVE
CLIMATOLOGY...WITH A FULLY MATURE LAKE MICHIGAN SHADOW KEEPING
NORTHWEST LOWER DRY...WITH SAID LAKE HURON LAKE BREEZES/INLAND
THERMAL LOWS DRIVING BEST SHOWER CHANCES ACROSS NORTHEAST LOWER. MAY
SEE A FEW INTERIOR EASTERN UPPER SHOWERS WHERE LAKE INDUCED
CONVERGENCE IS MAXIMIZED...WITH OVERALL COVERAGE GREATLY LIMITED BY
EVEN MORE MEAGER LOW LEVEL MOISTURE. SUNDAY STILL APPEARS DRY...
COURTESY OF WARMING MID LEVELS PREVENTING ANY DECENT INSTABILITY
FROM BEING REALIZED.

RATHER REMARKABLE AGREEMENT NEXT MID LEVEL IMPULSE ARRIVES SUNDAY
NIGHT INTO MONDAY. THIS ONE LOOKS TO BE ACCOMPANIED BY A SLOWLY
SOUTH SAGGING COOL FRONT...WHICH SHOULD HELP DRIVE SOME BETTER LOW
LEVEL CONVERGENCE. FORCING FAR FROM OVERWHELMING AT THIS EARLY
JUNCTURE...BUT STILL ENOUGH SUPPORT THERE TO CONTINUE WITH INHERITED
LOW POP THEME. DRY WEATHER LOOKS TO FOLLOW INTO MID WEEK AS SURFACE
HIGH PRESSURE SETTLES OVERHEAD...ALL-THE-WHILE MID LEVEL DRY
NORTHWEST FLOW PERSISTS. OF COURSE...ALL OF THIS IS SUBJECT TO
CHANGE...ESPECIALLY WITH REGARDS TO TIMING. PLENTY OF TIME TO FIGURE
OUT THOSE SPECIFICS IN THE COMING DAYS.

TEMPERATURES: READINGS MUCH CLOSER TO WHAT ONE WOULD EXPECT TO START
AUGUST...WITH HIGH TEMPERATURES MOSTLY IN THE MID AND UPPER 70S
FRIDAY THROUGH MONDAY (JUST ABOUT AT NORMAL). POST-FRONTAL COOLING
TUESDAY AND WEDNESDAY IS NOTHING TOO ALARMING...WITH READINGS
PERHAPS A FEW DEGREES BELOW NORMAL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1140 PM EDT WED JUL 30 2014

VFR CONDITIONS THROUGHOUT THE TAF PERIOD. UPPER LEVEL TROUGH IS
PRODUCING SPORADIC RAIN SHOWERS ACROSS NORTHERN LOWER
MICHIGAN. RAIN SHOWERS SHOULD END BY THE MORNING HOURS WITH
TROUGH AXIS EXPECTED TO PASS THROUGH THE FORECAST AREA. ANOTHER
MID LEVEL DISTURBANCE IS EXPECTED TO IMPACT NORTHERN MICHIGAN
DURING THE AFTERNOON HOURS...GENERATING SHOWERS ONCE AGAIN.
ALTHOUGH CONFIDENCE LEVEL IS LOW...AT THIS TIME RAIN CHANCES LOOK
THE BEST FOR THE APN AREA.


&&

.MARINE...
ISSUED AT 403 AM EDT THU JUL 31 2014

NO MARINE ISSUES TO BE CONCERNED WITH OVER THE NEXT SEVERAL DAYS.
WEAK PRESSURE GRADIENT AND RESULTANT WEAK WINDS BEING DOMINATED IN
THE AFTERNOONS BY ONSHORE LAKE BREEZES. THIS THE PATTERN THROUGH AT
LEAST EARLY NEXT WORK WEEK. SCATTERED SHOWERS TO AFFECT NEARSHORE
WATERS AGAIN THIS AFTERNOON ACROSS FAR NRN LAKE MICHIGAN...STRAITS
AND LAKE HURON.

&&

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

&&

$$

SYNOPSIS...MSB
SHORT TERM...SMD
LONG TERM...MSB
AVIATION...TL
MARINE...SMD