Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 201729
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
129 PM EDT WED MAY 20 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 321 AM EDT WED MAY 20 2015

UNDER A CLEAR SKY WITH A RIDGE EXTENDING ACROSS MUCH OF THE CWA
/PARTICULARLY W/ AND PW VALUES AROUND 0.25IN...TEMPERATURES HAVE
BEEN ABLE TO FALL INTO THE 20S INLAND FROM THE LAKE SUPERIOR
SHORELINE FROM ONTONAGON THROUGH THE KEWEENAW PENINSULA. THE MORE
STEADY NW FLOW BETWEEN THE RIDGE AND EXITING LOW OVER E CENTRAL
QUEBEC HAS KEPT TEMPS FROM FALLING AS DRAMATICALLY OVER FAR E UPPER
MI.

HIGHS TODAY WILL REBOUND 10-20F ABOVE WHERE THEY ENDED UP YESTERDAY
AS WE BRIEFLY RETURN TO NEAR NORMAL MID MAY WX. 850MB TEMPS WILL
IMPROVE TO 3-5C BY THE END OF THE DAY. EXPECT A MOSTLY SUNNY SKY
WITH AFTERNOON LAKE BREEZES OFF BOTH LAKE MI AND LAKE SUPERIOR...AND
MIXING TO 5-7KFT. HIGHS NEAR THE SHORELINES MAY REMAIN IN THE
50S...WITH AREAS INLAND REACHING THE LOW TO MID 60S. A FEW FCST
MODELS ARE INDICATING HIGHER CLOUD COVER...MAINLY HIGH CLOUDS
DRIFTING N FROM CENTRAL AND S WI DURING THE DAYTIME HOURS.

AS FOR TONIGHT...WE WILL BE WATCHING FOR POTENTIAL CLOUDS ASSOCIATED
WITH THE E-W ORIENTED COLD FRONT STRETCHED ACROSS S ONTARIO /JUST N
OF LAKE SUPERIOR/ AT 00Z THURSDAY SINK ACROSS THE KEWEENAW PENINSULA
AND JUST INLAND FROM LAKE SUPERIOR AROUND 12Z THURSDAY. ALTHOUGH
PRECIP IS NOT ANTICIPATED...THERE COULD BE A FEW-SCT CLOUDS AND PW
VALUES WILL INCREASE TO AROUND 0.5IN. INCREASED OVERNIGHT LOWS
SLIGHTLY FROM THE PREVIOUS FCST...STILL KEEPING LOW TO MID 30S OVER
THE E THIRD AWAY FROM LAKE SUPERIOR. WINDS JUST ABOVE THE SFC
/WITHIN A COUPLE THOUSAND FEET ABOVE THE SFC/ AHEAD OF THE COLD
FRONT OVERNIGHT WILL BE 20-25KTS. THESE WINDS ARE NOT EXPECTED TO BE
REALIZED AT THE SFC THANKS TO A STRONG INVERSION.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 408 AM EDT WED MAY 20 2015

THE BEGINNING OF THE LONG TERM FORECAST PERIOD LOOKS FAIRLY QUIET
FOR THE UPPER GREAT LAKES REGION...DUE TO THE AREA BEING BETWEEN AN
UPPER TROUGH OVER EASTERN CANADA AND ANOTHER OVER THE SOUTHWESTERN
CONUS. INTO THE WEEKEND...THE UPPER GREAT LAKES REGION WILL BE
DOMINATED BY GENERALLY A DRY AND COOLER NW FLOW ON THE BACKSIDE OF
THE ERN CANADIAN TROUGH. A FEW WEAK WAVES IN NW FLOW MAY BRUSH THE
AREA BUT WITH LIMITED MOISTURE AVAILABLE EXPECT MOSTLY A DRY
FORECAST.

SURFACE HIGH PRESSURE WILL DOMINATE MUCH OF THE AREA FROM THURSDAY
THROUGH AT LEAST THE SATURDAY NIGHT TIME PERIOD AS TEMPERATURES
GENERALLY RUN BELOW NORMAL (ESPECIALLY NEAR LAKE SUPERIOR). REALLY
THE ONLY ITEM OF NOTE DURING THE PERIOD IS A COLD FRONT THAT WILL
DROP SOUTH ACROSS THE REGION ON LATE TONIGHT AND THURSDAY. WITH
LIMITED LOW-LEVEL MOISTURE...EXPECT JUST PARTLY CLOUDY SKIES AS IT
MOVES THROUGH THE AREA. MODELS CONTINUE TO HINT THAT DIURNAL HEATING
(BOTH NAM AND CANADIAN MODELS HAVE MLCAPES APPROACHING 200 J/KG) MAY
BE ENOUGH TO KICK OFF A STRAY SHOWER OVER SOUTHERN PORTION OF
MENOMINEE COUNTY ON THU AS CONVERGENCE ALONG THE FRONT COULD BE
AIDED FROM A LAKE BREEZE DEVELOPING OFF THE BAY OF GREEN BAY.
GENERALLY EXPECT THE REST OF THE CWA TO BE DRY. ANOTHER BRIEF COOL
DOWN IS EXPECTED BEHIND THE FRONT THU-FRI DUE TO NORTHERLY FLOW OFF
LAKE SUPERIOR BEFORE HIGHS SLOWLY RISE TOWARDS MORE NORMAL VALUES ON
SATURDAY AS HIGH DEPARTS EAST AND SOUTHERLY FLOW STARTS TO DEVELOP.

00Z MODELS OFFER SIGNIFICANT DIFFERENCES ON TIMING OF SHORTWAVE
ENERGY EJECTING NE FROM THE SOUTHWESTERN CONUS TROUGH SUN INTO NEXT
TUE. 00Z GFS IS DEFINITELY MUCH QUICKER THAN EITHER THE ECMWF OR
CANADIAN MODELS WITH SHORTWAVE ENERGY AND ASSOC ISENTROPIC
LIFT/MOISTURE TRANSPORT AND THUS HAS PCPN DEVELOPING AS EARLY AS
LATE SAT NIGHT. MEANWHILE...THE ECMWF IS SLOWEST 00Z MODEL RUN...
MUCH SLOWER THAN GFS AND EVEN SLOWER THAN ITS PREV 12Z MODEL RUN. IT
MAINTAINS MID-LVL RIDGE AND DRY CONDITIONS ACROSS THE REGION INTO AT
LEAST SUNDAY EVENING WITH WAA PCPN AHEAD OF SHORTWAVE FINALLY
ARRIVING INTO THE FAR SW CWA LATE SUN NIGHT. GIVEN KNOWN GFS BIAS OF
TRYING TO DEVELOP PCPN TOO QUICKLY INTO ESTABLISHED RIDGE...AM
INCLINED TO LEAN TOWARD A SLOWER MODEL SOLN...ALTHOUGH 00Z ECMWF MAY
BE TOO SLOW. 00Z CANADIAN MODEL MAY OFFER BEST COMPROMISE AND AGREES
FAIRLY WELL WITH WPC PREFERRED 12Z ECMWF SOLN AND MODEL ENSEMBLES.
00Z CANADIAN MAINTAINS MID-LVL RIDGE AND MAINLY DRY CONDITIONS
THROUGH SUNDAY...THEN BRINGS PCPN IN FM SW LATER SUN EVENING INTO
MONDAY. THUS...WL CONTINUE WITH PREV FCST TRENDING POPS UPWARD FOR
SUNDAY NIGHT INTO MONDAY NIGHT WHEN MODEL ENSEMBLES SUGGEST
SHORTWAVE ENERGY AND ASSOC LOW PRES FROM THE PLAINS IS EXPECTED TO
MOVE THROUGH THE AREA. MODELS CONTINUE TO INDICATE BEST INSTABILITY
AND MID LEVEL LAPSE RATES STAYING WELL SOUTH DURING SUN NIGHT INTO
MON NIGHT TIME FRAME AS OUR FCST AREA IS GENERALLY ON THE NORTHWEST
SIDE OF THE SURFACE LOW...SO NOT EXPECTING ANY THUNDER. WEATHER
CONTINUES TO LOOKS UNSETTLED INTO THE MIDDLE OF NEXT WEEK AS THE
UPPER TROUGH IN THE SOUTHWEST CONUS WEAKENS AND LIFTS THROUGH THE
CENTRAL CONUS AND WRN GREAT LAKES REGION.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 129 PM EDT WED MAY 20 2015

VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES AS A HIGH PRESSURE
RIDGE WILL DEPART THE REGION. A COLD FRONT DROPPING SOUTH ACROSS
THE AREA LATE TONIGHT INTO TOMORROW MORNING WILL SHIFT WINDS TO THE
NORTH AND LEAD TO SCATTERED CLOUDS AROUND 6-8KFT.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 321 AM EDT WED MAY 20 2015

MUCH OF THIS PERIOD WILL BE DOMINATED BY HIGH PRESSURE...WITH WINDS
AROUND 25KTS OR LESS.

HIGH PRESSURE OVER THE DAKOTAS WILL SINK TO NEBRASKA THIS AFTERNOON
WHILE A E-W ORIENTED TROUGH NEARS FROM ONTARIO. THE LONG FETCH OF SW
WINDS OVER THE W HALF OF LAKE SUPERIOR MAY HELP PRODUCE SOME GUSTS
NEARING 20KTS OVER N CENTRAL LAKE SUPERIOR LATE THIS AFTERNOON INTO
THIS EVENING.

THE TROUGH WILL CROSS LAKE SUPERIOR TONIGHT...AND SINK INTO LAKE
MICHIGAN THURSDAY AFTERNOON. HIGH PRESSURE OVER NE MANITOBA THURSDAY
AFTERNOON WILL SLOWLY BUILD ACROSS THE UPPER GREAT LAKES THROUGH
FRIDAY...BEFORE EXITING TO THE LOWER GREAT LAKES AND OHIO VALLEY
FRIDAY NIGHT. A RIDGE OF HIGH PRESSURE WILL LINGER ACROSS LAKE
SUPERIOR THROUGH SUNDAY. A WEAKENING TROUGH MAY SINK ACROSS N LAKE
SUPERIOR ON SUNDAY...BUT THE IMPACT WIND WISE LOOKS MINIMAL.
&&

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

$$

SHORT TERM...KF
LONG TERM...VOSS
AVIATION...SRF
MARINE...KF



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