Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Text Only | 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 281918
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
318 PM EDT TUE APR 28 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 453 AM EDT TUE APR 28 2015

WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID LEVEL RIDGE
EXTENDING FROM IA TO JAMES BAY...SANDWICHED BTWN A SHORTWAVE TROF
MOVING ACROSS THE NRN PLAINS AND CONTINUED BROAD CYCLONIC
CIRCULATION ENCOMPASSING SE CANADA AND THE NE CONUS. THE MID LEVEL
RIDGE IS SUPPORTING SFC HIGH PRES OVER THE UPPER LAKES EARLY THIS
MORNING. TO THE W...APPROACHING SHORTWAVE TROF IS ACCOMAPANIED BY A
BAND OF SHRA IN NW MN.

APPROACHING SHORTWAVE TROF WILL REACH WRN UPPER MI LATE
AFTN/EVENING. WITH DEEP LAYER FORCING WEAKENING PER QVECTORS...A
LACK OF MOISTURE INFLOW...AND A VERY DRY ANTECEDANT AIR MASS PER 00Z
REGIONAL SOUNDINGS...MOST OF THE MODELS APPEAR ON TRACK SHOWING
APPROACHING PCPN DISSIPATING BEFORE REACHING UPPER MI LATE THIS
AFTN/EVENING. SO...PLAN TO MAINTAIN A DRY FCST. SECOND SHORTWAVE NOW
MOVING INTO NRN MANITOBA WILL MOVE INTO NRN ONTARIO AND THEN BEGIN
DIGGING MORE SHARPLY TO THE S TONIGHT WITH MODELS SUGGESTING A MID
LEVEL LOW BEGINNING TO CLOSE OFF JUST N OF LAKE SUPERIOR LATE
TONIGHT. THIS SHOULD SUPPORT AN EXPANSION OF PCPN N AND E OF LAKE
SUPERIOR TONIGHT...CLOSER TO GREATEST HEIGHT FALLS. PCPN MAY TRY TO
DEVELOP S INTO UPPER MI...BUT LACK OF DEEP FORCING HERE SUGGESTS DRY
WEATHER SHOULD CONTINUE THRU THE NIGHT.

AS FOR TEMPS...WEAK PRES GRADIENT TODAY WILL ALLOW LAKE BREEZE
DEVELOPMENT ACROSS THE BOARD...LEADING TO COOLER CONDITIONS ALONG
THE LAKES. IT WILL BE COOLEST IN THE ERN FCST AREA ALONG THE LAKE
SUPERIOR SHORE DUE TO ONSHORE WINDS THRU THE DAY. HIGHS WILL BE IN
THE 40S THERE. IN THE INTERIOR...FAVORED THE WARMER SIDE OF GUIDANCE
GIVEN THAT WARMER GUIDANCE HAS VERIFIED BETTER THE LAST COUPLE OF
DAYS. EXPECT HIGHEST TEMPS IN THE INTERIOR W WHERE MAX READINGS WILL
BE IN THE MID TO UPPER 60S. DEEP MIXING IN THE INTERIOR WILL TAP
DRIER AIR ALOFT...RESULTING IN AFTN DWPTS IN THE MID 20S...PERHAPS
LOWER. THIS WILL SEND RH DOWN TO AROUND 20PCT IN THE INTERIOR W.
FROM A FIRE WX STANDOINT...FORTUNATELY...WINDS WILL BE LIGHT TODAY.
LOWS TONIGHT WILL BE IN THE 30S.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 316 PM EDT TUE APR 28 2015

OVERALL...LITTLE CHANGES IN THE FORECAST THOUGHTS OVER THE LAST
24HRS...WITH THE REGION SEEING LIMITED PRECIPITATION CHANCES
THROUGH SUNDAY AND A TRANSITION TO ABOVE NORMAL TEMPERATURES. THIS
TRANSITION WILL BE LED BY AN UPPER RIDGE THAT WILL BUILD OVER THE
GREAT LAKES REGION ON THURSDAY NIGHT WHILE AN UPPER TROUGH BECOMES
ESTABLISHED OVER WESTERN CANADA. THIS WILL PLACE THE AREA UNDER
ZONAL FLOW FRIDAY INTO THE WEEKEND...WITH WEAK SHORTWAVES AND
SURFACE TROUGHS LEADING TO LOW CHANCES FOR PRECIPITATION.

BEFORE THAT UPPER RIDGE MOVES INTO THE AREA ON THURSDAY NIGHT...THE
START OF THE LONG TERM FORECAST WILL SEE A STRONG SHORTWAVE DIVING
SOUTH-SOUTHEAST ACROSS THE GREAT LAKES REGION. THE 700-500MB LOW
ASSOCIATED WITH THIS FEATURE WILL TRACK ACROSS EASTERN UPPER
MICHIGAN AND SHOULD KEEP ANY SHOWERS ASSOCIATED WITH THE SHORTWAVE
TO THE EAST OF A LINE FROM MUNISING TO MANISTIQUE. IT DID APPEAR
THAT THERE MAY BE ENOUGH NORTHERLY FLOW UPSLOPE HELP TO PRODUCE A
FEW SHOWERS/DRIZZLE OVER THE NORTH CENTRAL (NOT COLD ENOUGH FOR ICE
CRYSTALS AND SNOW)...SO DID ADD A MENTION OF RAIN TO THAT AREA FOR
WED NIGHT INTO THURS MORNING. THE DISTURBANCE WILL QUICKLY MOVE
SOUTH OF THE AREA WEDNESDAY NIGHT INTO THURSDAY...ALLOWING THE UPPER
RIDGE TO BUILD EAST INTO THE UPPER GREAT LAKES REGION FROM THE
NORTHERN PLAINS AND SOUTHERN CANADA. THAT WILL LEAD TO DRIER AIR
WORKING INTO THE AREA AND IN TURN DECREASING CLOUDS FROM WEST TO
EAST ON THURSDAY. EXPECT TEMPERATURES TO STILL REMAIN BELOW
NORMAL...ESPECIALLY OVER THE NORTH WITH THE COOL AIR COMING OFF LAKE
SUPERIOR.

FRIDAY WILL FEATURE A NICE START TO THE DAY IN THE U.P. WITH SUNNY
CONDITIONS ALLOWING TEMPERATURES TO WARM INTO THE 50S AND 60S. THE
NEXT DISTURBANCE (SLIDING EAST ALONG THE US/CANADIAN BORDER ON THE
LEADING EDGE OF THE UPPER TROUGH BECOMING ESTABLISHED IN WESTERN
CANADA WILL MOVE INTO WESTERN UPPER MICHIGAN IN THE AFTERNOON AND
THEN THE REST OF THE CWA THROUGH EARLY EVENING. THIS WILL LEAD TO
INCREASING CLOUDS DURING THE AFTERNOON. LIKE THE SHORTWAVE AND FRONT
THAT WILL BE MOVING THROUGH THE AREA THIS AFTERNOON/TONIGHT...IT
WILL BE RUNNING INTO EXISTING DRY AIR AND ALSO BECOMING SHEARED OUT.
THUS...EXPECT THE SYSTEM/PRECIPITATION TO DIMINISH AS IT SHIFTS INTO
THE WESTERN U.P. WILL CONTINUE TO SHOW SLIGHT CHANCE POPS OVER THE
WEST IN THE AFTERNOON AND THEN DIMINISHING AS IT SHIFTS EAST OVER
THE REST OF THE CWA IN THE EVENING.

BEHIND THAT DISTURBANCE...ZONAL FLOW BECOMES ESTABLISHED OVER THE
NORTHERN CONSUS AND EXPECT THAT TO LEAD TO ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE CWA. ECMWF HAS BEEN CONSISTENT (OVER
THE LAST 6-8 RUNS) WITH HIGHS IN THE UPPER 60S TO LOWER 70S ON
SATURDAY AT KSAW/KIWD/KIMT AND A FEW DEGREES WARMER FOR SUNDAY.
THUS...WILL TREND THEIR FORECASTS UP TOWARDS THAT IDEA FOR BOTH OF
THOSE DAYS. WITH WINDS GENERALLY LIGHT...SHOULD SEE LAKE BREEZES
DEVELOP ON SATURDAY. WILL NEED TO KEEP AN EYE ON A DISTURBANCE
FORECAST TO TRACK EAST OUT OF THE CENTRAL ROCKIES ON SATURDAY. AT
THIS POINT...IT LOOKS TO STAY TO THE SOUTH OF THE AREA...BUT THERE
HAVE BEEN SOME INDICATIONS THAT IT MAY SLIDE NORTH AND AFFECT THE
AREA ON SUNDAY. OTHERWISE...THE DEPARTING SURFACE RIDGE TO THE EAST
WILL LEAD TO LIGHT SOUTHERLY FLOW DEVELOPING ON SUNDAY.

THE BEST OPPORTUNITY FOR RAIN WILL COME SUNDAY NIGHT INTO MONDAY
MORNING...AS THE UPPER TROUGH OVER THE CANADIAN ROCKIES SHIFTS EAST
AND INTERACTS WITH WEAK DISTURBANCES LIFTING NORTHEAST OUT OF THE
CENTRAL/SOUTHERN ROCKIES. WILL FOCUS ON THIS TIME FOR THE BEST RAIN
CHANCES AND TREND POPS UP BEFORE DIMINISHING THEM ON MONDAY
AFTERNOON AS THE WAVES DEPART. STILL COULD SEE SOME SHOWER LINGERING
INTO MONDAY NIGHT OR EVEN TUESDAY MORNING DEPENDING ON HOW QUICKLY
THE UPPER TROUGH AXIS DEPARTS.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 131 PM EDT TUE APR 28 2015

ALTHOUGH A WEAK LOW PRES TROF WILL MOVE ACROSS THE AREA LATE THIS
AFTN AND EVENING...DRY AIR WILL PERSIST IN THE LOWER LEVELS...
ALLOWING VFR CONDITIONS TO PREVAIL THRU THE FCST PERIOD AT
KIWD/KCMX/KSAW. NORTH WINDS WILL LIKELY GUST OVER 15 KT AT KCMX AND
KSAW ON WED AHEAD OF HIGH PRES BUILDING DOWN FROM HUDSON BAY.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 453 AM EDT TUE APR 28 2015

WINDS ACROSS LAKE SUPERIOR WILL BE LIGHT...UNDER 15KT...THRU THIS
EVENING AS SFC HIGH PRES OVER THE AREA GIVES WAY TO A VERY WEAK LOW
PRES TROF THAT WILL PASS LATE THIS AFTN/EVENING. IN ITS WAKE...
ANOTHER HIGH PRES WILL BUILD OVER HUDSON BAY AND EXTEND A RIDGE S
INTO THE WRN GREAT LAKES WED/THU. AS THE HIGH BEGINS RIDGING S INTO
THE UPPER LAKES LATE TONIGHT/WED...NNW WINDS OVER ERN LAKE SUPERIOR
WILL LIKELY GUST TO AROUND 20KT. WINDS WILL BE LIGHTER OVER THE W.
WITH WEAK PRES GRADIENT OVER THE UPPER LAKES THU THRU SAT...WINDS
SHOULD BE LIGHT...MOSTLY UNDER 15KT.
&&

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

$$

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


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