Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KMQT 271943
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
343 PM EDT WED AUG 27 2014

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 334 PM EDT WED AUG 27 2014

QUIET WEATHER IS EXPECTED THROUGH THURSDAY AFTERNOON AS HIGH
PRESSURE SETTLES OVER UPPER MICHIGAN.

TONIGHT...A RIDGE OF SFC HIGH PRESSURE EXTENDING FROM NORTHWEST WI
TO NORTHERN ONTARIO WILL DRIFT EASTWARD THIS EVENING...SETTLING OVER
EASTERN UPPER MI OVERNIGHT. MEANWHILE...A MID-LEVEL RIDGE WILL TRACK
EASTWARD OVER THE UPPER MISSISSIPPI VALLEY. THE COMBINATION OF
MOSTLY CLEAR SKIES...LIGHT WINDS...AND PWATS AS LOW AS 0.4 INCHES
WILL ALLOW FOR CONSIDERABLE RADIATIONAL COOLING ACROSS THE CWA. THE
MOST ABUNDANT COOLING CAN BE EXPECTED ACROSS THE EASTERN CWA. ALL
INLAND LOCATIONS SHOULD DROP INTO THE 40S OVERNIGHT...WITH COLDER
LOCATIONS IN THE MID TO UPPER 30S. THIS WILL LEAD TO A FEW PATCHES
OF FROST FOR ANY TYPICAL COLD SPOTS ACROSS MAINLY THE INTERIOR EAST
HALF. ADDITIONALLY...WITH QUICK COOLING AND RESIDUAL NEAR-SFC
MOISTURE...PATCHES OF SHALLOW FOG MAY DEVELOP OVERNIGHT. AM NOT
EXPECTING ANYTHING OF MUCH CONCERN...BUT QUICK SPATIAL AND TEMPORAL
FLUCTUATIONS IN VISIBILITY WILL BE POSSIBLE.

THURSDAY...HIGH PRESSURE WILL BEGIN TO SHIFT EASTWARD IN THE
MORNING...ALLOWING FOR WEAK RETURN LOW-LEVEL FLOW ACROSS THE WEST
HALF OF THE CWA. THIS WILL RESULT IN SLIGHTLY WARMER TEMPS...AROUND
70...FOR MOST LOCATIONS. SOME AFTERNOON CUMULUS DEVELOPMENT WILL BE
POSSIBLE INLAND...THOUGH COVERAGE IS EXPECTED TO BE LESS THAN IT WAS
TODAY DUE TO LIMITED LOW-LEVEL MOISTURE.

BY THE AFTERNOON HOURS...MID TO HIGH-LEVEL CLOUDS WILL BE INCREASING
FROM THE SW IN RESPONSE TO THE APPROACH OF A MID-LEVEL SHORTWAVE
TROUGH CURRENTLY OVER THE NORTHERN ROCKIES. MODEL
TRENDS...ESPECIALLY FROM THE NAM...HAVE INDICATED A SLOWER
PROGRESSION OF THE ASSOCIATED SFC LOW WITH EACH SUBSEQUENT RUN. HAVE
THUS BACKED OFF ON CLOUDS A SMALL AMOUNTS...AND KEPT ALL PRECIP OUT
OF THE FORECAST UNTIL 00Z. SEE THE LONG TERM DISCUSSION FOR
INFORMATION ABOUT PRECIP CHANCES THURSDAY EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 519 AM EDT WED AUG 27 2014

THRU THE BEGINNING OF THE UPCOMING WEEKEND...A LOW AMPLITUDE
PROGRESSIVE NRN STREAM FLOW REGIME WILL PREVAIL ACROSS SRN CANADA. A
WEAKER SRN BRANCH FLOW ACROSS THE CONUS WILL CAUSE ISSUES WITH
REGARD TO PCPN OVER THE UPPER LAKES...DEPENDING ON INTERACTION OF
SHORTWAVES WITH THE MORE PROGRESSIVE FLOW TO THE N. RIGHT NOW...THE
SRN BRANCH FEATURES A TROF AND WELL-DEFINED SHORTWAVE OVER THE SRN
ROCKIES. EARLY NEXT WEEK...FLOW WILL AMPLIFY SOME AS A MORE
SUBSTANTIAL TROF MOVES INTO THE NW CONUS AND THEN SHIFTS EASTWARD.
OVERALL...THIS PATTERN WILL SUPPORT TEMPS GENERALLY AROUND NORMAL TO
A BIT BLO OVER THE NEXT FEW DAYS. BRIEF WARMING WILL OCCUR EARLY
NEXT WEEK AHEAD OF THE MORE SUBSTANTIAL TROF PROGRESSING E ACROSS
THE NW AND NCNTRL CONUS. PCPN FCST IS QUITE UNCERTAIN. THERE IS THE
POTENTIAL FOR AT LEAST A COUPLE OF ROUNDS OF PCPN THRU THE UPCOMING
WEEKEND...DEPENDING ON EVOLUTION OF SRN BRANCH SHORTWAVES. ANOTHER
PERIOD OF PCPN SHOULD OCCUR EARLY NEXT WEEK AS COLD FRONT SWEEPS
ACROSS THE AREA IN ASSOCIATION WITH AFOREMENTIONED TROF MOVING
ACROSS THE NW/NCNTRL CONUS.

BEGINNING THU/FRI...ATTENTION TURNS TO SHORTWAVE LIFTING OUT OF THE
SRN BRANCH TROF CURRENTLY OVER THE SRN ROCKIES. WITH NRN STREAM
TROFS MOVING ACROSS THE CANADIAN ROCKIES AND QUEBEC/NEW ENGLAND...
THERE WILL BE AN OPPORTUNITY FOR THE SRN BRANCH SHORTWAVE TO MAKE
SOME NORTHWARD PROGRESS. MODELS HAVE OVERALL MOVED INTO BETTER
AGREEMENT ON WAA/MOISTURE ADVECTION LIFTING N AND SPREADING PCPN
INTO UPPER MI THU NIGHT/FRI. HOWEVER...THERE ARE STILL SOME
DIFFERENCES AS THE GEM/ECMWF/NAM ARE MORE AGGRESSIVE SPREADING MAIN
AREA OF PCPN MORE SQUARELY ACROSS THE FCST AREA. THE GFS IS FOCUSED
MORE TO THE S AND E. GIVEN TRENDS AND GFS SOMEWHAT ON ITS OWN...
RAISED POPS SOME FOR LATER THU NIGHT/FRI MORNING WITH LIKELY POPS
FROM THE SCNTRL TO THE ERN FCST AREA. WILL NEED TO CONTINUE UPWARD
TREND IF NEXT ROUND OF MODELS STAYS ON TRACK. INSTABILITY IS RATHER
LIMITED. ONLY INCLUDED THUNDER SCNTRL AND E. AFTER SOME PATCHY FOG
EARLY THU...SUNSHINE WILL GIVE WAY TO INCREASING HIGH CLOUDS. MIXING
TO 850-800MB ON FCST SOUNDINGS SUGGEST HIGH TEMPS THU WILL BE MOSTLY
IN THE LOW/MID 70S AWAY FROM LAKE COOLING.

OVER THE WEEKEND...FCST HAS BECOME MORE UNCERTAIN AS THERE IS A
TREND FOR THE MAIN ENERGY CURRENTLY IN THE SRN ROCKIES TROF TO LIFT
FARTHER N. ASSOCIATED WEAK SFC WAVE IS FCST TO TRACK ACROSS SRN WI
AND THRU NRN LWR MI. GIVEN TRENDS ALONG WITH DECENT AGREEMENT AMONG
00Z MEDIUM RANGE GUIDANCE...WILL LINGER CHC POPS OVER THE SE HALF OF
THE FCST AREA FRI NIGHT...THEN SPREAD CHC POPS BACK N AND W SAT/SAT
NIGHT. LOOKS LIKE SUN SHOULD DRY OUT WITH SHORTWAVE RIDGE ARRIVING
BTWN DEPARTING SHORTWAVE AND AHEAD OF MORE SIGNIFICANT TROF
DEVELOPING INTO THE NW CONUS.

AS THE MORE SUBSTANTIAL TROF OVER THE NW CONUS SHIFTS EASTWARD EARLY
NEXT WEEK...A COLD FRONT WILL SWEEP E ACROSS THE GREAT LAKES...
BRINGING A DECENT POTENTIAL FOR SHRA/TSRA. FOR THIS FAR OUT IN THE
MODEL RUNS...AGREEMENT IS GOOD ON TIMING FRONT. THE ECMWF HAS
NOTABLY TRENDED FASTER TOWARD THE GFS WHICH IS TYPICALLY MORE
PROGRESSIVE...AND THE GEM OFFERS SIMILAR TIMING. THESE LATEST RUNS
SUGGEST FRONT CROSSING UPPER MI MON AFTN/NIGHT. SO IT LOOKS LIKE
LABOR DAY MIGHT TURN WET WITH SHRA AND TSTMS SPREADING E ACROSS THE
AREA.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 133 PM EDT WED AUG 27 2014

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT ALL SITES...EXCEPT
FOR SOME MVFR VIS AT SAW OVERNIGHT. SCATTERED TO BROKEN LOW-END VFR
STRATOCUMULUS WILL DISSIPATE BY AROUND 00Z. HIGH PRESSURE WILL THEN
BRING MOSTLY CLEAR SKIES AND LIGHT WINDS TONIGHT...ALLOWING FOR
PATCHY BR TO DEVELOP AT SAW. VIS MAY FLUCTUATE CONSIDERABLY DURING
THE OVERNIGHT HOURS...BUT ANY BR OR FG SHOULD BE QUITE SHALLOW AND
DISSIPATE SHORTLY AFTER SUNRISE THURSDAY.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 334 PM EDT WED AUG 27 2014

HIGH PRESSURE OVER THE UPPER GREAT LAKES WILL BRING LIGHT WINDS
UNDER 15 KNOTS THROUGH THURSDAY. THE HIGH WILL SHIFT EAST THURSDAY
NIGHT...ALLOWING A COUPLE WEAK SURFACE TROUGHS TO MOVE THROUGH THE
REGION THROUGH SUNDAY. THE WEAK PRESSURE GRADIENTS ASSOCIATED WITH
THESE TROUGHS WILL KEEP WINDS BELOW 20KTS. A STRONGER TROUGH WILL
THEN CROSS THE UPPER GREAT LAKES MONDAY AFTERNOON AND
NIGHT...BRINGING SOUTH WINDS UP TO 25 KNOTS MONDAY...AND SOUTHWEST
WINDS UP TO 20 KNOTS MONDAY NIGHT INTO TUESDAY.
&&

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

$$

SHORT TERM...KLUBER
LONG TERM...ROLFSON
AVIATION...KLUBER
MARINE...KLUBER






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.