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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
645 AM EDT SAT AUG 23 2014

.SYNOPSIS...
ISSUED AT 246 AM EDT SAT AUG 23 2014

HIGH PRESSURE TO OUR EAST WILL PROVIDE FOR LIGHT SOUTHERLY 
BREEZES...AND INCREASING WARMTH AND HUMIDITY THROUGH MONDAY. FOR
THE MOST PART THE WEEKEND LOOKS DRY...BUT SHOWERS AND THUNDERSTORM
CHANCES WILL INCREASE ON MONDAY...AHEAD OF A WEAK COLD FRONT
THAT WILL ENTER NORTHERN MICHIGAN MONDAY NIGHT.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 246 AM EDT SAT AUG 23 2014

HIGH IMPACT WEATHER POTENTIAL: MINIMAL

PRIMARY FORECAST CHALLENGES: DO SHOWERS MOVE INTO NORTHERN MICHIGAN?

CURRENTLY, AS WAS MENTIONED AT THE EARLIER UPDATE, RAIN SHOWERS 
UPSTREAM OF THE FORECAST AREA ARE JUST SOUTH OF MQT AND SAW AND 
ALONG THE 700 MB DEWPOINT DEPRESSION GRADIENT, AND IN THE LFQ OF THE 
500 MB 30 KNOT JET STREAK MOVING THROUGH N WISCONSIN. MAIN FORCING  
THAT IS GOING ON OVERNIGHT IS OVER FARTHER SOUTH AND WEST IN 
NEBRASKA WHERE THE DEEPER SFC LOW AND 500 MB VORT AND SPEED MAXES 
ARE DIGGING. THIS HAS GIVEN RISE TO THE COMPLEX OF STORMS IN THE 
CENTRAL PLAINS. THE SFC LOW IN THE E COLORADO IS LINKED BY A SLOWLY 
STRENGTHENING FRONT THAT STRETCHES TO THE NE THROUGH N MINNESOTA AND 
UP INTO JAMES BAY TO A WEAKER SFC LOW. 

TODAY...THE MODELS ARE IN GOOD AGREEMENT WITH THE 
RUC/NAM12/GFS/ECMWF/LOCAL WRF4KM SHOWING THE MORNING ISOLATED 
SHOWERS THAT WILL TRY TO PUSH INTO NW LOWER THIS MORNING. HOWEVER, 
AS THE 500 MB RIDGE OVER THE UPPER GREAT LAKES CONTINUES TO AMPLIFY, 
THE FORCING FOR THE SHOWERS WILL GET PUSHED TO THE NORTH AND WEST 
THROUGH THE AFTERNOON. THE FRONT WILL ALSO MOVE TO THE NORTH AND 
WEST AS THE SFC LOW IN E COLORADO MOVES OUT OVER THE CENTRAL PLAINS 
AND DEEPENS. THIS WILL HELP TO FOCUS MOST OF THE RAIN INSTABILITY 
AND THE DYNAMIC SUPPORT OVER THE NORTHERN PLAINS AS DEPICTED BY SPC. 

TONIGHT...THIS MOVEMENT OF THE SFC LOW OUT OF THE CENTRAL PLAINS 
WILL PUSH INTO NORTH DAKOTA OVERNIGHT CONTINUING TO PULL THE FOCUS 
AWAY FROM THE UPPER GREAT LAKES. THIS SHOULD CONTINUE OUR RAIN FREE 
STREAK (OR AT LEAST OUR MEASURABLE PRECIPITATION) THROUGH THE NIGHT. 
WHILE THERE IS SOME INSTABILITY, THE LACK OF A FOCUS AND THE CAPPING 
EXPECTED IN THE EVENING (BLAYER CIN 20-40 J/KG) SHOULD INHIBIT ANY 
SHOWERS FROM GETTING GOING. IT DOESN'T LOOK LIKE THERE IS MUCH IN 
THE WAY OF ELEVATED INSTABILITY AS THE SHOWALTER INDEX OVER N 
MICHIGAN AT ITS LOWEST IS ONLY +2C. 

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 246 AM EDT SAT AUG 23 2014

A HIGHLY AMPLIFIED 500MB RIDGE WILL BE OVERHEAD TO START OUR SUNDAY. 
AN EJECTING UPPER LOW FROM THE NORTHERN HIGH PLAINS WILL HAVE TO 
CREST THIS RIDGE...AND WILL PASS WELL TO OUR NORTH MONDAY NIGHT. 
THIS WILL FLATTEN OUT THE RIDGE...THOUGH IN OUR NECK OF THE WOODS 
500MB HEIGHTS WILL HARDLY LOWER AT ALL. STILL...AN ASSOCIATED COLD 
FRONT WILL SLOWLY GET DRAGGED INTO THE AREA MONDAY NIGHT. UNTIL THAT 
HAPPENS...IT WILL BE SOMETHING OF A CHALLENGE TO GET A PRECIP THREAT 
GOING IN THESE PARTS. BUT IT WON/T BE CHALLENGING TO BECOME 
INCREASINGLY WARM AND HUMID.

SUNDAY...CORE OF THE 500MB RIDGE STARTS TO SLIDE DOWNSTREAM IN THE 
AFTERNOON. THAT CORRESPONDS WITH A SLIGHT UPTICK IN 1000-850MB 
RETURN FLOW. HOWEVER...A SHORTWAVE RIDGE ASCENDING INTO THE LARGER 
RIDGE WILL HELP KEEP HEIGHTS HIGH. AT THE SAME TIME...SURFACE HIGH 
PRESSURE TO OUR EAST WILL STILL EXTEND A TOUCH OF RIDGING INTO 
NORTHERN MI. FROM A CONCEPTUAL MODEL STANDPOINT...IT WILL BE 
DIFFICULT TO FIRE OFF CONVECTION IN THIS PATTERN UNTIL HEIGHTS ALOFT 
FALL. INDEED...THE MODELS ARE NOT INCLINED TO PROG MUCH IF ANY CAPE. 
00Z NAM HAS A LATE-DAY AXIS OF A FEW HUNDRED J/KG OF MUCAPE... 
HUGGING THE LAKE MI COAST FROM LTL TRAV BAY SOUTH. THIS IS WHERE 
LAKE BREEZE CONVERGENCE AND MOISTURE POOLING WILL BE CONCENTRATED... 
THANKS TO A BACKGROUND LIGHT SE SYNOPTIC SURFACE WIND. EVEN SO...AN 
82/65 PARCEL HAS ABOUT 50J/KG OF CIN TO OVERCOME...THANKS TO 700MB 
TEMPS AROUND 9C.

SO WILL MAINTAIN A DRY FORECAST. CAN GENERALLY EXPECT PARTLY SUNNY 
SKIES...WILL SOME BUBBLY CU AND MID/HIGH DEBRIS CLOUDS (INSTABILITY 
WILL BE MUCH HIGHER W OF LAKE MI). MAX TEMPS UPPER 70S (EASTERN 
UPPER...AND NE LOWER COAST)...TO LOW/MID 80S (INTERIOR SW SECTIONS).

SUN NIGHT/MONDAY...SUB-850MB FLOW MAINTAIN AN EASTERLY COMPONENT 
INTO THE EVENING...BEFORE VEERING S TO EVEN SSW OVERNIGHT. THAT WILL 
ALLOW A JUICIER AND POTENTIALLY UNSTABLE AIRMASS TO FINALLY MAKE 
INROADS. HOWEVER...THAT WILL BE SLOW AT 1ST...WITH PERHAPS WESTERN 
CHIP/MACK THE ONLY PLACE PROGGED TO SEE SOME CAPE ARRIVE BY MORNING. 
THIS COULD ALLOW CONVECTION ORIGINATING IN WI A CHANCE TO GRAZE BY 
THAT AREA OVERNIGHT. BUT...GIVEN THE MODELS TEND TO BE TOO QUICK TO 
BREAK DOWN RIDGING AND CIN...WILL MAINTAIN A DRY FORECAST FOR SUN 
NIGHT. 

DEEP MOISTURE/MODERATE INSTABILITY PLUME WILL VERY SLOWLY WORK IN 
FROM THE WNW MONDAY...AHEAD OF A COLD FRONT ADVANCING ACROSS WI. 
HEIGHTS/TEMPS ALOFT HERE REMAIN HIGH...BUT ACTIVITY SHOULD DEVELOP 
UPSTREAM IN WI AND MOVE E AND NE TOWARD WESTERN/NORTHERN 
SECTIONS...ESPECIALLY LATER IN THE DAY. WILL MAINTAIN CHANCE POPS BY 
AFTERNOON IN THE NW 2/3DS OF THE FORECAST AREA...INCLUDING HIGH 
CHANCE (50) POPS IN WESTERN CHIP/MACK. 

MIN TEMPS NEAR 60F TO THE MID 60S. MAX TEMPS NEAR 80 TO THE MID 
80S...A FEW UPPER 80S POSSIBLE IN THE INTERIOR OF NORTHERN LOWER. 
DEW POINTS WILL BE RISING INTO THE MID AND UPPER 60S...SO IT WILL 
ALSO BE QUITE STICKY ON MONDAY.

REST OF THE FORECAST...SHAPING UP FOR A FAVORABLE MCS PATTERN 
MID-WEEK. A STALLED FRONTAL ZONE (AND A WARM/HUMID AIRMASS) WILL BE 
JUST TO OUR SOUTH...WITH FAST ZONAL FLOW IN THE NORTHERN LAKES. 
CONSALL GRIDS ARE TRYING TO NUDGE US TOWARD LIKELY POPS IN SOME 
PERIODS. AM BACKING AWAY FROM THIS THINKING GIVEN THAT IT/S 
CONVECTION WE/RE TALKING ABOUT...AND PRECIP HAS UNDERPERFORMED OVER 
THE LAST WEEK OR SO. TEMPS WILL BE DRIFTING BACK TOWARD OR A BIT 
UNDER CLIMO BY LATE IN THE WORK WEEK...THOUGH PROBABLY NOT AS COOL 
AS THE GFS/MEX GUIDANCE ADVERTISES...AS THE ECMWF IS SLOWER AND LESS 
AMPLIFIED WITH THE UPPER TROF THAT PROGRESSES INTO THE PLAINS STATES 
MID/LATE WEEK. 

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 645 AM EDT SAT AUG 23 2014

FOG TO BURN OFF THIS MORNING...THEN VFR THRU THIS EVENING. SOME
FOG AGAIN LATE TONIGHT.

HUMID AIRMASS WILL REMAIN IN PLACE THIS WEEKEND. WITH LIGHT WINDS
AT NIGHT...FOG HAS BEEN AN ISSUE...AND THAT WILL CONTINUE. PLN/APN
GETTING THE WORST OF IT THIS MORNING...LIFR AT TIMES. THAT WILL
ONLY LAST 1-2 HOURS PAST 12Z AT MOST. THEN VFR. LIFR FOG IS AGAIN
LIKELY AT APN/PLN LATE TONIGHT...HAVE ADDED MVFR CONDITIONS TO MBL
LATE AS WELL.

LIGHT WINDS.

&&

.MARINE...
ISSUED AT 246 AM EDT SAT AUG 23 2014

OVER THE NEXT 48 HOURS, THE WINDS WILL SLOWLY INCREASE AND VEER
FROM THE EAST TO THE SOUTH LOW PRESSURE NEAR COLORADO DEEPENS AND
MOVES INTO NORTH DAKOTA. SO TODAY THROUGH SUNDAY NIGHT, WILL
EXPECT THAT WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT
CONDITIONS. 


&&

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

&&

$$

SYNOPSIS...JZ
SHORT TERM...JL
LONG TERM...JZ
AVIATION...JZ
MARINE...JL

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