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 202005
AFDMQT

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

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 331 PM EDT WED MAY 20 2015

A HIGH PRESSURE RIDGE THAT WAS OVER UPPER MICHIGAN THIS MORNING HAS
BEEN SLOWLY SHIFTING SOUTH THROUGH THE DAY...AS THE SURFACE HIGH IN
WESTERN SOUTH DAKOTA MOVES INTO WESTERN NEBRASKA. THIS HAS LED TO A
NICE DAY ACROSS THE U.P. BUT NOW HIGH CLOUDS ARE STREAMING EAST-
NORTHEAST ACROSS THE SOUTHERN HALF OF THE AREA. THESE HIGH CLOUDS
ARE ASSOCIATED WITH A BROAD MOISTURE PLUME ON WATER VAPOR IMAGERY
SLIDING NORTHEAST ACROSS THE CENTRAL PLAINS AND INTO THE LOWER GREAT
LAKES. THE CIRRUS WILL LIKELY CONTINUE EAST-NORTHEAST ACROSS THE
AREA THIS EVENING BEFORE CLEARING OUT DURING THE OVERNIGHT HOURS.

WITH THE HIGH PRESSURE RIDGE SLIDING SOUTH OF THE AREA THIS
EVENING...MUCH OF THE FORECAST WILL BE FOCUSED ON THE COLD FRONT
THAT WILL DROP SOUTH FROM ONTARIO LATE TONIGHT INTO THURSDAY. THIS
FRONT IS CURRENTLY IN STRETCHING FROM SOUTH OF JAMES BAY TO NEAR
WINNIPEG. BEHIND THE FRONT IN FAR NORTHERN ONTARIO...THERE IS
ABUNDANT LOW CLOUDS AND EVEN A FEW SNOW REPORTS. DON/T THINK MUCH OF
THAT WILL MAKE IT TO THIS AREA...AS IT APPEARS TO BE VERY SHALLOW ON
THE CYYQ SOUNDING AND DIURNAL MIXING HAS ERODED SOME OF IT. WITH THE
LOW LEVEL NORTHWESTERLY FLOW AND PIVOTING OF THE FRONT THAT
DIRECTION...THINK THE BETTER LOW CLOUDS WILL STAY OFF TO THE EAST OF
THE AREA. THAT BEING SAID...IT STILL LOOKS THERE WILL BE ENOUGH
MOISTURE AROUND 750-650MB TO PRODUCE CLOUDS OVER THE EASTERN HALF TO
TWO-THIRDS OF THE CWA TOMORROW MORNING INTO EARLY AFTERNOON. WILL
CONTINUE TO SHOW PARTLY CLOUDY SKIES SLIDING SOUTH ACROSS THE AREA
DURING THAT PERIOD (WITH SOME SPOTS OF MOSTLY CLOUDY OVER THE EAST).
AS THAT MOISTURE AND SURFACE FRONT REACHES THE SOUTH CENTRAL U.P.
DURING PEAK HEATING...THERE COULD BE A STRAY SHOWER OVER SOUTHERN
MENOMINEE COUNTY (AIDED BY A LAKE BREEZE OFF THE BAY OF GREEN BAY)
BEFORE QUICKLY SLIDING SOUTH OF THE AREA BY 22Z. BEHIND THAT POCKET
OF MOISTURE...SKIES SHOULD QUICKLY CLEAR BACK OUT.

LOWS TONIGHT WILL BE WARMER THAN LAST NIGHT WITH THE DEPARTURE OF
THE SURFACE HIGH AND VERY DRY AIR HAVING EXITED THE AREA. STILL
EXPECT TO SEE SOME SUB FREEZING TEMPERATURES OVER THE EASTERN HALF
OF THE CWA AT THE TRADITIONAL COLD SPOTS (BETWEEN THE DEPARTING HIGH
CLOUDS AND THE LATE ARRIVING MID CLOUDS). ON THURSDAY...HIGHS WILL
BE THE WARMEST OVER THE SOUTH CENTRAL WITH THE LATER ARRIVAL OF THE
FRONT. WHILE THE COLDEST AIR IS DELAYED BEHIND THE FRONT UNTIL LATE
THURSDAY AFTERNOON AND INTO THE EVENING...THE NORTHERLY FLOW OFF
LAKE SUPERIOR SHOULD HELP KEEP TEMPERATURES COOLER OVER THE NORTHERN
HALF OF THE U.P. AND GENERALLY IN THE 50S. THE COOLEST VALUES WILL
BE RIGHT NEAR LAKE SUPERIOR EAST OF MARQUETTE (IN THE 40S)...AS THAT
IS WHERE THE COLDEST POCKET OF AIR TRAVELS AND THERE IS UNIMPEDED
NORTHWEST-NORTHERLY WINDS OFF THE 35 DEGREE WATER TEMPERATURES.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 404 PM EDT WED MAY 20 2015

NORTHWESTERLY CONFLUENT FLOW ALOFT ON WESTERN EDGE OF TROUGH
CENTERED ON EASTERN CANADA PERSISTS THROUGH THE WEEKEND...SO SFC
HIGH PRESSURE WILL BE THE MAIN WEATHER FEATURE. TROUGH ALOFT STAYS
OVER WESTERN HALF OF CONUS WHICH KEEPS MAIN SFC LOW AND WARM FRONT
OVER CENTRAL PLAINS. WEAK COLD FRONT DROPS FROM NORTHERN ONTARIO ON
SATURDAY TO THE UPPER GREAT LAKES ON SUNDAY. APPEARS TROUGH ALOFT
WILL TRY TO BRIEFLY LIFT TOWARD GREAT LAKES EARLY NEXT WEEK WHICH
BRINGS SFC LOW AND WARM FRONT CLOSE ENOUGH TO SUPPORT INCREASING
CHANCES OF RAIN. ADDITIONAL FOCUS FOR RAIN MAY ALSO COME VIA YET
ANOTHER NORTHERN STREAM SHORTWAVE AND COLD FRONT THAT CLOSES IN ON
UPPER GREAT LAKES TUESDAY INTO WEDNESDAY.

EXPECT MINIMAL HIGH IMPACT WEATHER ISSUES THROUGH THE LONG TERM.
LINGERING DRY AIRMASS WILL RESULT IN ANOTHER CHILLY NIGHT ON
THURSDAY NIGHT WITH TEMPS AGAIN FALLING BLO FREEZING INLAND. DRY
AIRMASS THEN RESULTS IN LOWER MIN HUMIDITY VALUES FOR FRIDAY AFTN
WITH H85 DWPT DEPRESSIONS OVER 20C. WINDS LESS THAN 15 MPH WITH THE
HIGH OVERHEAD AND ONGOING GREEN UP COMBINE TO MITIGATE FIRE WEATHER
ISSUES.

NOT AS CHILLY FRIDAY NIGHT AS WEST WINDS START TO STIR AHEAD OF WEST
TO EAST ORIENTED FRONT DROPPING OVER NORTHERN ONTARIO. STRONGER WEST
WINDS EXPECTED ON SATURDAY. WINDS/GUSTS ON LAND SHOULD STAY BLO 25
MPH...BUT MAY HAVE A FEW SMALL CRAFT ADVISORIES TO DEAL WITH FOR
START OF THE MEMORIAL DAY WEEKEND. TEMPS ON SATURDAY SHOULD BE ABLE
TO REACH WELL INTO 70S IN MANY AREAS AS WEST-SOUTHWEST WINDS
MINIMIZE LAKE BREEEZES FOR ALL BUT KEWEENAW AND NEAR LK MICHIGAN.
HUMIDITY VALUES NOT AS LOW AS FRIDAY...BUT COULD SEE RH DOWN TO 25-
30 PCT OVER INLAND LOCATIONS. WILL HAVE TO KEEP MONITORING SATURDAY
BECAUSE IF WINDS END UP STRONGER OR MIN RH LOWER THAT DAY COULD END
UP WITH NEAR CRITICAL FIRE WEATHER CONDITIONS IN SOME AREAS.

INCREASING MID-LEVEL RH TO THE NORTH OF WARM FRONT COULD TRIGGER
SHOWERS SATURDAY NIGHT INTO SUNDAY FM WI OVER UPR MICHIGAN...BUT
CHANCES LOOK SLIM GIVEN MINIMAL INSTABILITY OR LARGER SCALE
LIFT...BOTH OF WHICH STAY TO THE SOUTHWEST OF UPPER GREAT LAKES.
STRONGEST MOISTURE TRANSPORT FM H85-H7 REMAINS SOUTH OF HERE SO THAT
ALSO SUGGESTS LOW CHANCES OF SHOWERS OVER UPR MICHIGAN. DID NOTICE
THAT 12Z GFS AND NAM INCREASE THIN LAYER OF MID LEVEL RH ON SATURDAY
AFTN. GFS TRIES TO SHOW QPF OVER AREA WHICH SEEMS WAY OVERDONE GIVEN
SHALLOWNESS OF THE MOIST LAYER. WILL KEEP IT DRY ON SATURDAY AND
BRING IN LOW CHANCES LATER SATURDAY NIGHT INTO SUNDAY. MODELS REMAIN
IN DISAGREEMENT ON FORECAST FOR SUNDAY. LAST FEW RUNS OF GFS STILL
PERSISTENT IN BRINGING SFC LOW AND WARM FRONT FARTHER NORTH AND SHOW
WIDESPREAD QPF OVR UPR MICHIGAN ON SUNDAY. ECMWF AND GEM-NH
SLOWER...BRINGING QPF IN LATER SUNDAY NIGHT OR EVEN ON MONDAY.
BLOCKY/SLOW PROGRESSION OF UPPER LEVEL PATTERN WOULD FAVOR SLOWER
ARRIVAL OF MAIN SHOWERS IN WARM AND MOIST ADVECTION ALOFT OVER THE
UPR GREAT LAKES...BUT WILL KEEP LOW CHANCES SHOWN BY CONSENSUS WITH
A NOD TO THE PERSISTENT GFS. EVEN BY MONDAY WHEN CHANCES INCREASE
FURTHER ON ALL MODELS...LEFT OUT TSRA AS ECMWF/GFS INDICATE MINIMAL
MLCAPES OR EVEN ELEVATED MUCAPES. GREATER RISK SHOULD BE ALONG AND
SOUTH OF THE WARM FRONT...WHICH DOES NOT SEEM TO MAKE IT AS FAR
NORTH AS UPPER GREAT LAKES.

AS FAR AS TEMPS GO...NO SIGNIFICANT WARMING OR COOLING BEYOND
SATURDAY. OVERALL THE TEMPS SHOULD END UP PRETTY CLOSE TO NORMAL.
ONLY THING THAT WOULD LEAD TO COOLER TEMPS IS IF IT ENDS UP CLOUDIER
WITH MORE RAIN FOR ANY OF THE DAYS SUNDAY THROUGH WEDNESDAY. SUPPOSE
ONE OF THOSE DAYS COULD SEE THAT KIND OF SETUP AND BEING NORTH OF
THE WARM FRONT WOULD HAVE THE ADDED ISSUE OF WINDS OFF THE GREAT
LAKES LEADING TO COOLER TEMPS. NO CONFIDENCE ON THOSE TYPE OF
DETAILS NOW THOUGH.
&&

.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 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 331 PM EDT WED MAY 20 2015

A HIGH PRESSURE RIDGE CURRENTLY OVER THE UPPER GREAT LAKES REGION
WILL SHIFT SOUTH AS A COLD FRONT MOVES SOUTH OUT OF NORTHERN
ONTARIO TONIGHT. THIS WILL SHIFT WINDS TO THE NORTH LATE TONIGHT
INTO THURSDAY. WITH COLDER AIR MOVING ACROSS THE AREA BEHIND THE
FRONT...WINDS WILL GUST UP TO 25KTS OVER EASTERN LAKE SUPERIOR ON
THURSDAY AFTERNOON. AN AREA OF HIGH PRESSURE QUICKLY DROPPING SOUTH
FROM CANADA ON THURSDAY NIGHT WILL DIMINISH THE WINDS BELOW 20KTS
AND KEEP THEM THERE THROUGH SUNDAY. WHILE A BROAD LOW PRESSURE
SYSTEM WILL MOVE THROUGH THE GREAT LAKES REGION ON MONDAY...WINDS
ARE STILL EXPECTED TO REMAIN BELOW 20KTS.
&&

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

$$

SHORT TERM...SRF
LONG TERM...JLA
AVIATION...SRF
MARINE...SRF


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