Area Forecast Discussion Issued by NWS Gaylord, MI
000
FXUS63 KAPX 200235
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1035 PM EDT WED JUN 19 2013
.SYNOPSIS...
ISSUED AT 346 PM EDT WED JUN 19 2013
HIGH PRESSURE WILL REMAIN OVER THE GREAT LAKES THROUGH TONIGHT...
PROVIDING MAINLY CLEAR SKIES AND SEASONAL TEMPERATURES. THIS
SYSTEM WILL SLIP OFF TO THE SOUTHEAST BY THURSDAY ALLOWING A FRONT
TO SAG INTO AND THEN STALL ACROSS NORTHERN MICHIGAN HEADING INTO
THE WEEKEND. THIS WILL RESULT IN PERIODIC CHANCES OF SHOWERS AND
THUNDERSTORMS BEGINNING THURSDAY AND PERSISTING THROUGH THE
WEEKEND.
&&
.UPDATE...
ISSUED AT 1035 PM EDT WED JUN 19 2013
HIGH PRESSURE OVER LAKE ONTARIO IS EXTENDING A RIDGE AXIS WEST
INTO LOWER MI. SKIES ARE ESSENTIALLY CLEAR...A FEW SHREDS OF
CIRRUS ARE EAST AND NORTH OF EASTERN UPPER. HOWEVER...THE ONSET OF
WARM ADVECTION ON THE NW FLANK OF THE SURFACE RIDGE IS
CONTRIBUTING TO SOME MID CLOUDS ON SUPERIOR...WHICH ARE SLOWLY
WORKING SE. DO EXPECT AN INCREASING CLOUD TREND IN EASTERN UPPER
OVERNIGHT.
FURTHER NW...A DECAYING BAND OF SHRA/TSRA IS NEAR THE
NORTH SHORE OF SUPERIOR. THIS IS AHEAD OF A COLD FRONT WHICH IS
STILL NORTH OF THUNDER BAY ONT. INCREASING 850-700MB FGEN...AND
BEING AT THE NOSE OF A 20-25KT 850MB JET...SHOULD SUPPORT SOME
ACTIVITY OVER SUPERIOR THRU THE NIGHT. HOWEVER...SE-WARD PROGRESS
WILL BE SLOW...AS INFLOW IS SERIOUSLY LACKING IN OUR NECK OF THE
WOODS (850MB WINDS 5-10KT). SUSPECT EASTERN UPPER MI WILL STAY DRY
THRU 12Z.
TEMPS AGAIN RACING DOWN THRU THE 50S...THOUGH DEW POINTS ARE
RIDING A FEW DEGREES HIGHER. WILL LOWERING TEMPS SLIGHTLY IN A FEW
SPOTS.
UPDATE ISSUED AT 732 PM EDT WED JUN 19 2013
A SCT-BKN LINE OF FLAT CU LINGERS ALONG A LAKE BREEZE COLLISION
FRONT EXTENDING FROM MANTON TO NORTH OF HILLMAN. CLOUD FORECAST
HAS BEEN UPDATED FOR THE LATEST TREND...OTHERWISE NO CHANGES
NEEDED ON THIS QUIET EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 346 PM EDT WED JUN 19 2013
LATEST SURFACE ANALYSIS SHOWS LARGE 1022MB HIGH CENTERED OVER
EASTERN LAKE HURON...HELPING TO KEEP CONDITIONS BEAUTIFUL OVER
NORTHERN MICHIGAN WITH JUST FEW PASSING CIRRUS AND DIURNALLY
DRIVEN CUMULUS CLOUDS. FURTHER TO THE WEST...MORE CU ACTIVITY WAS
SEEN BACK OVER ILLINOIS...WISCONSIN AND POINTS
WESTWARD...ASSOCIATED WITH SOUTHEASTERLY RETURN FLOW BRINGING A
MOISTURE RETURN THERE. THE CLOSEST WEATHER MAKER TO US IS
ASSOCIATED WITH A SHORTWAVE WAY TO OUR NORTH MOVING OUT OF NRN
MANITOBA INTO NRN ONTARIO AND THE JAMES BAY. AN ASSOCIATED LOW
PRESSURE SYSTEM AND TRAILING COLD FRONT WAS SEEN WITH THIS
FEATURE...HELPING TO TOUCH OFF SOME RAIN SHOWERS IN ONTARIO WITH
EVEN A COUPLE OF LIGHTNING STRIKES SEEN OVER SW ONTARIO LATE THIS
AFTERNOON.
TONIGHT...NOT TOO MUCH TO WORRY ABOUT FOR TONIGHT...WITH DRY AIR
REMAINING IN PLACE AND ANOTHER MAINLY CLEAR NIGHT ACROSS MOST OF
THE CWA. NOT LOOKING AS COLD AS LAST NIGHT...AS THE RETURN FLOW ON
THE BACKSIDE OF THE HIGH WILL JUST BE GETTING UNDERWAY. VERY
LIGHT SOUTHERLY WINDS WILL KEEP TEMPS UP A BIT...WITH PERHAPS A
SLIGHT UPTICK IN DEW POINTS. THE LOW LYING AREAS OVER INTERIOR
PORTIONS COULD STILL SEE LOWS DIP INTO THE LOWER 40S. WOULD NOT BE
SURPRISED TO EVEN SEE A ROGUE SUB 40 DEGREE READING OVER PLACES
SUCH AS GOV AND THE OTHER NORMAL COLD SPOTS. THE TRAILING COLD
FRONT WILL BE MOVING THROUGH THE U.P. OVERNIGHT...BRINGING SOME
SCATTERED SHOWERS AND PERHAPS A FEW THUNDERSTORMS TO WESTERN AND
CENTRAL SECTIONS OF THE U.P. CLOUDS WILL BE ON THE INCREASE FOR
EASTERN UPPER...WITH PERHAPS SOME SHOWERS MOVING IN TO NRN
CHIPPEWA COUNTY AFTER 09Z TONIGHT. INSTABILITY IS LACKING OVER THE
EASTERN U.P...AND THE WEAKENING FRONTAL FORCING WILL KEEP THUNDER
OUT OF THE FORECAST FOR THERE.
THURSDAY...THE REMNANTS OF THE FRONT STALL OUT OVER THE EASTERN
U.P. FOR THURSDAY. BY THIS TIME...AM HARD PRESSED TO FIND ANY DECENT
CONVERGENCE ALONG THE FRONTAL ZONE...AND WITH THE BETTER SYNOPTIC
QG FORCING WELL TO THE NORTH OF THE CWA...WILL MAINTAIN LOW CHC
POPS WITH MOSTLY CLOUDY SKIES FOR EASTERN UPPER FOR THE DAY. FOR
NRN LOWER MICHIGAN...HIGH PRESSURE SHOULD REMAIN IN CONTROL...WITH
A SOUTHERLY RETURN FLOW HELPING TO BOOST TEMPERATURES UP SEVERAL
NOTCHES FROM TODAY...ALONG WITH A BIT OF AN INCREASE IN HUMIDITY.
IN TERMS OF SENSIBLE WEATHER IT WILL BRING A BIT MORE CU DURING
THE AFTERNOON...AND MAYBE SOME MID/HIGH LEVEL CLOUDS WITH THE
FRONTAL BOUNDARY...HELPING TO FILTER THE SUNSHINE FROM TIME TO TIME
TOWARD THE STRAITS. HIGHS LOOK TO BE WELL INTO THE 70S TO AROUND
80...COOLER OVER THE U.P. DUE TO CLOUD COVER. WHILE THIS BOUNDARY
IN THE U.P. REMAINS QUITE WEAK TOMORROW...IT MAY BECOME
REINVIGORATED LATE THIS WEEK AS STRONG SOUTHERLY FLOW AHEAD OF
DEVELOPING LOW PRESSURE MOVES INTO THE GREAT LAKES...SERVING AS A
FOCUS FOR THUNDERSTORM CHANCES LATE THIS WEEK. MORE ON THAT IN THE
LONG TERM SECTION.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 346 PM EDT WED JUN 19 2013
SUMMER TIME PATTERN SHAPING UP OVER THE NEXT SEVERAL DAYS WITH
RISING HEIGHTS ALOFT/WARMING 850 MB TEMPERATURES. THE COMBINATION OF
UPPER LEVEL DISTURBANCES TOPPING THE BUILDING UPPER LEVEL RIDGE AND
A STALLED OUT SURFACE BOUNDARY IN THE VICINITY WILL LEAD TO NUMEROUS
CHANCES FOR SHOWERS AND THUNDERSTORMS. FORECAST HIGH TEMPERATURES
WILL BE CHALLENGING DUE TO UNCERTAINTY OVER TIMING/LOCATION OF
POSSIBLE CONVECTIVE COMPLEXES. ONE THING THAT YOU CAN TAKE TO THE
BANK...IT WILL TURN MUCH MORE HUMID. THE MAIN FORECAST CONCERNS
REVOLVE AROUND POPS AND HIGH TEMPERATURES THROUGH THE ENTIRE LONG
TERM.
THURSDAY NIGHT...HIGH PRESSURE CONTINUES TO MOVE OFF TO OUR EAST
ALLOWING FOR A MORE MOIST SOUTHERLY SURFACE FLOW WITH 700 MB THETA-E
RIDGE ENCROACHING FROM THE WEST. IT LOOKS LIKE A BOUNDARY LIES OUT
ACROSS EASTERN UPPER SO THERE WILL BE A CHANCE FOR SHOWERS AND EVEN
THUNDERSTORMS AS INSTABILITY INCREASES UP THAT WAY. NOT NEARLY AS
COOL WITH LOWS IN THE MIDDLE AND UPPER 50S.
FRIDAY...THETA-E RIDGE SETTLES ACROSS THE FORECAST AREA.
MEANWHILE...A CORE OF STRONG WINDS ALOFT MOVES BY THE NORTH WITH
0-6KM BULK SHEAR APPROACHING 50 KNOTS ACROSS EASTERN UPPER AND 40
KNOTS ACROSS NORTHERN LOWER. SO WITH A SURFACE BOUNDARY DRAPED
ACROSS NORTHERN SECTIONS OF THE REGION IN COMBINATION WITH DAYTIME
HEATING...COULD SEE SOME THUNDERSTORM DEVELOPMENT (POSSIBLY ON HE
STRONG SIDE). TOUGH TEMPERATURE FORECAST WITH THE AMOUNT OF CLOUD
COVER AND POSSIBLE CONVECTION IN QUESTION. CONTINUED TO PLAY IT ON
THE CONSERVATIVE SIDE IN THIS REGARD WITH HIGHS RANGING FROM THE
MIDDLE 70S TO LOWER 80S.
FRIDAY NIGHT THROUGH NEXT WEDNESDAY...STATUS QUO WITH UPPER LEVEL
RIDGING AND THE STALLED OUT FRONT ACROSS THE REGION...LEADING TO
NUMEROUS CHANCES FOR ROUNDS OF SHOWERS AND THUNDERSTORMS. WISH COULD
BE MORE DETAILED BUT MODELS VARY ON INDIVIDUAL SMALLER SCALE
FEATURES SO WILL CONTINUE TO KEEP THE FORECAST GENERAL AND GO WITH
CHANCE POPS THROUGH THE PERIOD. HAVE INCHED TEMPERATES UP A LITTLE
EACH DAY...REACHING THE MIDDLE 70S NORTH TO MIDDLE 80S CENTRAL AND
SOUTH BY MONDAY...PERHAPS EVEN THE UPPER 80S SOUTHEAST. THERE IS THE
POTENTIAL TO TOP 90 DEGREES AS 850 MB TEMPERATURES NEAR 20C...BUT
LIKE WAS SAID EARLIER...THERE IS TOO MUCH UNCERTAINTY TO KNOW MIXING
DEPTH. PERHAPS A BIT OF RELIEF FROM THE HEAT AND HUMIDITY ON
WEDNESDAY AS A WEAK FRONT LOOKS LIKE IT WILL MOVE THROUGH FROM THE
NORTHWEST. LOWS AT NIGHT MAINLY IN THE UNCOMFORTABLE 60S TO NEAR
70.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 732 PM EDT WED JUN 19 2013
VFR. HIGH PRESSURE OVER THE EASTERN LAKES WILL CONTINUE TO EXTEND
RIDGING BACK INTO NORTHERN MI...EVEN AS THE CENTER OF THE HIGH
MOVES FURTHER EAST. THAT WILL KEEP THE NORTHERN LOWER MI AIRMASS
DRY. LIGHT WINDS TONIGHT...JUST A TOUCH OF SOUTHERLY BREEZE
THURSDAY THAT WILL GIVE WAY TO LAKE BREEZES.
&&
.MARINE...
ISSUED AT 346 PM EDT WED JUN 19 2013
LIGHT WINDS ASSOCIATED WITH HIGH PRESSURE WILL RESULT IN CALM
CONDITIONS OVER THE LAKES THROUGH THURSDAY INTO THE WEEKEND. NO
SMALL CRAFT ADVISORIES ARE EXPECTED WITH STABLE CONDITIONS
REMAINING. INCREASING HEAT AND HUMIDITY LATE THIS WEEK...COMBINED
WITH A STATIONARY FRONTAL BOUNDARY WILL BRING A RETURN TO
THUNDERSTORM CHANCES THURSDAY NIGHT INTO FRIDAY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...BA
SHORT TERM...NS
LONG TERM...AS
AVIATION...JZ
MARINE...NS