Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Text Only | 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 181244
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
844 AM EDT SAT APR 18 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 439 AM EDT SAT APR 18 2015

LOOK FOR THE GUSTY EARLY MORNING WINDS TO CONTINUE TO DIMINISH AS
THE AREA OF GREATEST PRESSURE CHANCE OVER THE NW HALF OF LAKE
SUPERIOR AT 06Z DIMINISHES IN INTENSITY AS IT PROGRESSES ACROSS
CENTRAL AND E LAKE SUPERIOR/UPPER MI BY 12Z. DRY WEATHER WILL REMAIN
AS COOL HIGH PRESSURE FROM THE NW CONTINUES TO BUILD INTO THE CWA
THIS MORNING. NOT ONLY WILL HIGH PRESSURE BE BUILDING AT THE
SFC...THE 500MB RIDGE WILL ALSO BE STRENGTHENING ITS GRIP ACROSS
UPPER MI.

DAYTIME MINIMUM RH VALUES WILL BE SIMILAR TO THOSE REALIZED
YESTERDAY...BOTTOMING OUT IN THE 15-20 PERCENT RANGE OVER THE
INTERIOR W HALF...WHILE 25-20 PERCENT OVER THE INTERIOR E HALF.
COOLER AIR FLOWING IN ON THE GENERALLY N /NW TO NE/ FLOW OFF LAKE
SUPERIOR SHOULD KEEP AREAS ALONG LAKE SUPERIOR CLOSER TO 40 PERCENT.
THIS WILL BE DESPITE TEMPS TOPPING OUT 5-10 DEGREES COOLER THAN
YESTERDAY.

THE SFC HIGH OVER THE AREA AT 18Z TODAY WILL SHIFT ALONG THE
ONTARIO/QUEBEC BORDER BY 06Z SUNDAY. THE RESULT WILL BE WAA AHEAD OF
THE AREA OF LOW PRESSURE SET UP FROM S MANITOBA THROUGH THE PLAINS
STATES. TONIGHT WILL BRING YET ANOTHER PERIOD OF STRONGER NIGHT TIME
WINDS...AT LEAST ABOVE THE SFC. WILL NEED TO MONITOR APPROACHING
RAIN OVER THE FAR W. ANY RAIN COULD BRING DOWN THE 30-40KT WINDS
THAT WILL BE HOVERING JUST ABOVE THE SFC /BELOW 900MB/.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 247 AM EDT SAT APR 18 2015

NAM SHOWS TWO 500 MB TROUGHS WITH THE SOUTHERN ONE OVER THE CENTRAL
PLAINS AND THE NORTHERN ONE OVER THE NORTHERN PLAINS 12Z SUN. THE
SOUTHERN TROUGH GETS ABSORBED INTO THE NORTHERN TROUGH WHICH HELPS
TO SLOW DOWN THE EASTWARD MOVEMENT OF THE NORTHERN SYSTEM. THE
TROUGH CONTINUES TO SLOWLY MOVE INTO THE UPPER GREAT LAKES WHERE A
500 MB LOW MOVES INTO LAKE SUPERIOR MON NIGHT. NAM SHOWS SOME DEEPER
MOISTURE AND 850-500 MB Q-VECTOR CONVERGENCE MOVING IN SUN INTO SUN
NIGHT. LOOKS LIKE THERE COULD BE A DRY SLOT MOVING THROUGH ON MONDAY
ACROSS THE CENTRAL CWA AND HAVE LOWEST POPS THERE. DID REMOVE SNOW
FROM FORECAST FOR MONDAY AS LOOKED TOO WARM FOR IT TO OCCUR WITH
SYSTEM SLOWING DOWN A BIT AND COLDER AIR LAGGING...BUT KEPT IT IN
FOR MON NIGHT. OTHERWISE...DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST.

IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH AND CLOSED 500
MB LOW AFFECTING THE UPPER GREAT LAKES 12Z TUE. THE TROUGH MOVES
SLOWLY EAST 12Z WED...BUT STILL AFFECTS THE UPPER GREAT LAKES ON WED
INTO FRI. THIS WILL MEAN COLD AND UNSETTLED WEATHER THIS FORECAST
PERIOD WITH TEMPERATURES REMAINING WELL BELOW NORMAL. WILL HAVE A
RAIN/SNOW POSSIBILITY FOR POPS FOR THIS PERIOD WITH SNOW
ACCUMULATIONS MINIMAL.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 843 AM EDT SAT APR 18 2015

A POCKET OF MVFR CLOUDS DEVELOPED EARLY THIS MORNING UNDER THE LOW
LEVEL NORTHEASTERLY FLOW AND CONTINUED AT ALL THREE SITES AT THE
TAF ISSUANCE TIME. WITH THE VERY SHALLOW NATURE OF THE
MOISTURE...WOULD EXPECT DIURNAL HEATING TO MIX THE CLOUDS OUT
THROUGH THE MORNING. THEN...EXPECT VFR CONDITIONS TO PREVAIL FOR
THE REST OF THE PERIOD AS MID AND HIGH CLOUDS BEGIN TO SPREAD NORTH
AHEAD OF A LOW PRESSURE SYSTEM THAT WILL AFFECT THE REGION SUNDAY
AND MONDAY. THIS COULD LEAD TO SOME RAIN SHOWERS AT KIWD LATE
IN THE PERIOD. FINALLY...EXPECT LOW LEVEL WIND SHEAR TO AFFECT ALL
THREE SITES LATE THIS EVENING AND INTO THE OVERNIGHT HOURS AS
SOUTH-SOUTHEASTERLY WINDS INCREASE AHEAD OF THE LOW.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 439 AM EDT SAT APR 18 2015

HIGH PRESSURE OVER NW ONTARIO WILL DRIFT EAST INTO QUEBEC ON SUNDAY.
MEANWHILE...A LOW MOVING INTO MN ON SUNDAY MORNING WILL MERGE WITH
ANOTHER LOW LIFTING NE INTO THE LOWER LAKES...RESULTING IN A DEEPER
LOW PRESSURE NEAR THE UPPER GREAT LAKES ON MONDAY. SE WINDS GUSTING
TO NEAR 30KTS WILL BE POSSIBLE OVER MAINLY NORTHERN AND CENTRAL
LAKE SUPERIOR ON SUNDAY AFTERNOON-SUNDAY EVENING.

ALTHOUGH THE LOW WILL SHIFT NE TO NEAR JAMES BAY ON TUESDAY...A
TROUGH WILL EXTEND BACK INTO THE UPPER GREAT LAKES. THESE FEATURES
WILL REMAIN NEARLY STATIONARY BUT WEAKEN SLOWLY THROUGH
WEDNESDAY...TO THE EAST OF RIDGE BUILDING OVER THE N PLAINS.
&&

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

$$

SHORT TERM...KF
LONG TERM...07
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.