000
FXUS63 KMQT 230001
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
801 PM EDT WED MAY 22 2013

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 353 PM EDT WED MAY 22 2013

12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SLUGGISH UPR LO
OVER THE UPR MS RIVER VALLEY BTWN RDG OFF THE SE CONUS AND ANOTHER
RDG AXIS OVER THE ROCKIES. BAND OF -SHRA STRETCHING FM NE MN INTO
THE WRN CWA UNDER BAND OF H85-7 FGEN TO THE NE OF THE CLOSED LO IS
HOLDING FIRM EVEN THOUGH LLVL DRY AIR IS SURGING INTO NE MN/WRN LK
SUP IN STEADY NE FLOW BTWN HI PRES OVER NRN MANITOBA AND SFC LO PRES
IN THE LOWER LKS. ANOTHER LARGER AREA OF SHRA/ISOLD TS OVER THE SE
HALF OF WI/S HALF OF LK MI IS EXPANDING TO THE N AS SHRTWV OVER
IL/LEFT EXIT REGION OF SUPPORTING H3 JET MAX IS MOVING N OF THE
CLOSED LO. OTRW...LO CLDS HAVE BEEN QUITE PERSISTENT OVER UPR MI
WITH CHILLY NE WIND OFF LK SUP. SOME FOG HAS PERSISTED AS WELL NEAR
LK SUP E OF THE KEWEENAW...WHERE THE LLVL DRY AIR HAS NOT YET
ARRIVED.

MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE HOW DRIER AIR ARRIVING
FM THE N WL IMPACT POPS ASSOCIATED WITH BAND OF FGEN OVER THE WRN
ZNS AND AREA OF SHRA MOVING N TOWARD THE SE COUNTIES.

TNGT...UPR LO NOW OVER SE MN IS PROGGED TO DRIFT ESE...AND NAM SHOWS
BAND OF H85-7 FGEN/H85-5 QVECTOR CNVGC FOLLOWING THIS FEATURE SEWD
ACRS MAINLY THE W HALF OF THE CWA. AT THE SAME TIME...H7-3 QVECTOR
CNVGC/UPR DVGC IN LEFT EXIT AHEAD OF SHRTWV/SUPPORTING UPR JET
LIFTING NNEWD WL IMPACT MAINLY THE SE COUNTIES. LOOKS LIKE THESE
DYNAMICS MAY INTERACT FOR A TIME LATE THIS AFTN/EARLY EVNG OVER THE
SE ZNS. SO HIER POPS IN THIS AREA AT THAT TIME SEEM APPROPRIATE. AT
THE SAME TIME...DRIER AIR SURGING INTO THE NW CWA UNDER STRONGER NNE
FLOW WL END ANY LINGERING PCPN AS FGEN AXIS SHIFTS TO THE SE. THE
PCPN WL END EVEN OVER THE SE ZNS AFT 06Z FOLLOWING DEPARTURE OF
SHRTWV/ACCOMPANYING DYNAMICS AND ARRIVAL OF DRIER LLVL AIR. THE
ARRIVAL OF THE DRIER LLVL AIR AND EXIT OF THE DYNAMICS WL ALLOW FOR
SOME CLRG...BUT THE UPSLOPE NNE FLOW MAY SLOW THE PROCESS OVER THE
HIER TERRAIN NEAR LK SUP.

THU...HI PRES IS FCST TO BLD INTO THE UPR LKS...RESULTING IN DRY WX.
ALTHOUGH LINGERING H85 THERMAL TROF WITH TEMPS ARND 0C THRU 00Z
WOULD INDICATE QUITE A BIT OF DIURNAL CU/SC AT THIS TIME OF YEAR
OVER LAND...DRYNESS OF INCOMING AIRMASS AS WELL AS LLVL ACYC/
DIFFLUENT FLOW WL RESULT IN MOCLR SKIES. IF THERE IS ANY UPSLOPE SC
OVER THE HIER TERRAIN NEAR LK SUP...THIS CLD WL MIX OUT EARLY. THE
FCST H85 TEMPS AND MIXING TO H8-85 ON NAM FCST SDNGS YIELDS HI TEMPS
TOPPING OUT IN THE 50S OVER THE INTERIOR. BUT STIFF NNE WIND OFF LK
SUP WL CAUSE TEMPS TO HOLD IN THE 40S NEAR THE BIG LAKE. THESE
STRONGER NE WINDS WL DIMINISH OVER THE W IN THE AFTN WITH THE APRCH
OF THE HI CENTER/WEAKENING PRES GRADIENT.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 353 PM EDT WED MAY 22 2013

SLOW MOVING AND RATHER STABLE UPPER AIR PATTERN EXPECTED THROUGH THE
ENTIRE LENGTH OF THE LONG TERM. INITIALLY LATE THIS WEEK...THERE IS
A TROUGH OVER PACIFIC NORTHWEST WITH RIDGING OVER CENTRAL CONUS...
AND TROUGHING OVER MUCH OF EASTERN CANADA ACROSS THE GREAT LAKES.
EXPECT BELOW NORMAL TEMPERATURES TO PREVAIL THROUGH THE HOLIDAY
WEEKEND AS THE TROUGH ONLY SLOWLY MOVES TO THE EAST. EVENTUALLY...
WARMER TEMPERATURES ARE EXPECTED BY MIDDLE OF NEXT WEEK WHEN RIDGING
EXPANDS FROM PLAINS ACROSS THE GREAT LAKES. AFTER AN UNSETTLED AND
WET WEEK THAT HAS OCCURRED OVER THE UPPER GREAT LAKES...HUDSON BAY
HIGH PRESSURE RIDGING ACROSS THE GREAT LAKES SHOULD BRING A
PROLONGED PERIOD OF DRY WEATHER INTO NEXT WEEK. CERTAINLY POSSIBLE
THIS DRY WEATHER STRETCH MAY EVEN PERSIST INTO THE MIDDLE OF NEXT
WEEK. WARM FRONT FORMING TO THE SOUTH AND WEST OF UPPER MICHIGAN
WILL RESULT IN SOME SMALLER CHANCES OF PRECIP BY NEXT WEDNESDAY...
BUT GIVEN THE VERY DRY AIRMASS IN PLACE...GREATEST CHANCE OF SHOWERS
AND STORMS WILL LIKELY STAY TO WEST OF UPPER LAKES CLOSER TO AXIS OF
HIGHER H85-H7 MOISTURE AND INSTABILITY.

GUSTY WINDS AROUND ON THURSDAY DIMINISH BY THE WEEKEND AS HIGH
PRESSURE BUILDING SOUTH OUT OF NORTHERN ONTARIO BECOMES MORE
ESTABLISHED. LIGHTER WINDS ON THURSDAY NIGHT AND VERY DRY AIRMASS
OVERHEAD DUE TO STRONG MIXING EARLIER IN THE DAY WILL SUPPORT MIN
TEMPS DROPPING TO AROUND 20 DEGREES INTERIOR WEST AND IN THE 20S TO
LOWER 30S ELSEWHERE. EXPECT WIDESPREAD FROST FOR MANY AREAS ON
THURSDAY NIGHT. WE DO NOT OFFICIALLY BEGIN THE FROST AND FREEZE
HEADLINES UNTIL MEMORIAL DAY BUT WILL CONTINUE TO INCLUDE MENTION IN
THE GRIDS. WITH STRONG HIGH PRESSURE OVER THE AREA...NEAR 1030MB...
LAKE BREEZES MAY GET GUSTY AT TIMES THIS WEEKEND. AFTER A COOLER DAY
ALL AREAS ON FRIDAY...COOLING WILL BECOME MORE OF A LAKESIDE FEATURE
THROUGH THE WEEKEND AS INLAND AREAS RISE INTO THE 60S.

SEEMS THERE IS A SLIM CHANCE OF LGT RAIN/SPRINKLES OVER FAR WEST
CWA LATE FRIDAY NIGHT INTO SATURDAY MORNING. 12Z NAM SOUNDINGS SHOW
MOISTURE IN MID LEVELS ENHANCED BY RIGHT ENTRANCE REGION OF
DEPARTING JET STREAK OVER ONTARIO BUILDING DOWN ENOUGH ALONG WITH
SUFFICIENT UVM TO RESULT IN BAND OF LGT SHRA MAKING IT INTO IWD
06Z-12Z ON SATURDAY. ECMWF/GFS SHOW SOME MID LEVEL MOISTURE BUT HAVE
QPF STAYING OUT OF CWA. 12Z ECMWF DOES SHOW A BIT NOW THOUGH. NAM
SEEMS TOO AGGRESSIVE WITH EASTWARD PUSH OF LGT PRECIP SO WILL NOT
PUT A MENTION IN YET. INCREASE IN CLOUDS OVERNIGHT WILL IMPACT MIN
TEMPS AND MAY RESTRICT POTENTIAL FOR FROST...AT LEAST IN THE
INTERIOR WEST CWA. ELSEWHERE...TEMPS DROPPING INTO THE UPPER 20S OR
NEAR 30 DEGREES WILL SUPPORT MORE FROST...ESPECIALLY INLAND FROM THE
LAKES. IF THERE ARE BKN CLOUDS WEST...THEY SHOULD DISSIPATE BY
SATURDAY EVENING RESULTING IN ANOTHER COOL NIGHT WITH SOME FROST
INLAND FROM THE GREAT LAKES SHORES.

DUE TO COOL AND DAMP WEATHER AND MODERATE RAIN AMOUNTS IN SOME AREAS
/HAD REPORT TODAY OF OVER 4 INCHES TO WEST OF ONTONAGON/...FIRE
WEATHER ISSUES ARE TAKING A BRIEF HIATUS. EVENTUALLY DUE TO ALMOST A
WEEK OF DRYING...INCREASING SOUTH/SOUTHWEST WINDS...AND WARMER
TEMPERATURES INTO THE 70S EARLY-MID NEXT WEEK MAY SEE INCREASING
FIRE WEATHER CONCERNS FOR AREAS THAT HAVE NOT EXPERIENCED A FULL
GREEN UP AND/OR SEEN A LOT OF RAIN OVER THE LAST FEW DAYS.
&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 748 PM EDT WED MAY 22 2013

AS A STEADY NNE WIND BTWN HIGH PRES IN SCENTRAL CANADA AND LOW PRES
OVER THE LOWER GREAT LAKES WILL ADVECT MUCH DRIER LOW LEVEL AIR OVER
UPPER MI. EXPECT IMRPVOING CONDITIONS TO EVENTUALLY SPREAD TOWARD
SAW BY LATE EVENING WHERE THE MORE SIGNIFICANT UPSLOPE WIND
COMPONENT WILL ALSO SLOW THE TREND TOWARD VFR. UNDER A TIGHTENING PRES
GRADIENT...EXPECT GUSTY NNE WINDS AT ALL 3 SITES TONIGHT THROUGH
THU.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 353 PM EDT WED MAY 22 2013

EXPECT INCREASING NE WINDS UP TO 25-30 KTS UNDER SHARPENING PRES
GRADIENT IN ADVANCE OF HI PRES BUILDING TOWARD LAKE SUP THRU
TONIGHT. THIS STRENGTHENING FLOW WILL ADVECT DRIER AIR OVER THE
LAKE...SO LINGERING FOG SHOULD DISSIPATE THIS EVENING. BASED ON
CURRENT VISIBILITY REPORTS/WEBCAM IMAGERY NEAR THE LAKE...OPTED TO
CANX GOING DENSE FOG ADVISORIES THAT WERE SET TO EXPIRE AT 21Z.
CLOSER APPROACH OF HI PRES/WEAKER PRES GRADIENT WILL RESULT IN
SLOWLY DIMINISHING WINDS W TO E ON THU. AS HIGH PRESSURE CONTINUES TO
SPREAD ACROSS THE UPPER GREAT LAKES THROUGH THE WEEKEND...EXPECT
WINDS LESS THAN 20 KTS ON LAKE SUPERIOR. LIGHTER WINDS WILL CONTINUE
INTO EARLY NEXT WEEK.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...KC
LONG TERM...JLA
AVIATION...JLB
MARINE...KC/JLA