Area Forecast Discussion
Issued by NWS Marquette, MI

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000
FXUS63 KMQT 281127
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
727 AM EDT SUN JUN 28 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM EDT SUN JUN 28 2015

UPPER AIR PATTERN CONSISTS OF A 500 MB CLOSED LOW OVER LAKE ERIE
EMBEDDED IN A TROUGH OVER THE LOWER GREAT LAKES...A SHORTWAVE ACROSS
MN AND A STRONG 500 MB RIDGE ACROSS THE ROCKIES THIS MORNING. THIS
SHORTWAVE WILL CONTINUE TO HEAD SSE AND PASS TO THE WEST OF THE AREA
THIS FORECAST PERIOD.

NAM SHOWS SOME WEAK 850-500 MB Q-VECTOR CONVERGENCE REMAINING OVER
THE U.P. THIS FORECAST PERIOD WITH DEEPER MOISTURE REMAINING OFF TO
THE WEST OF THE CWA. GFS AND ECMWF SHOW ABOUT THE SAME THING AS
WELL.

OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST AS
LAKE BREEZE CONVERGENCE WILL HELP TO KICK OFF SOME SHOWERS AND
THUNDERSTORMS LATE THIS MORNING INTO THIS EVENING AND THIS WAS
COVERED IN THE FORECAST EXCEPT DID EXTEND LAKE BREEZE CONVECTION
INTO THE EVENING HOURS. KEPT THE POPS IN THE CHANCE CATEGORY.
STUBBORN SHOWER THIS MORNING HAS CONTINUED ACROSS IRON COUNTY AND
HAD TO KEEP ADJUSTING THE ISOLATED POP GRID TO LONGER AS THIS SHOWER
REFUSES TO DISSIPATE. DEFINITELY NOT DIURNALLY DRIVEN...BUT LATEST
TRENDS HAVE BEEN FOR IT TO SHRINK AND HAVE IT DISSIPATING SHORTLY.
MADE VERY FEW CHANGES TO THE TEMPERATURE FORECAST.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 401 AM EDT SUN JUN 28 2015

MAIN CONCERNS THROUGH THE EXTENDED ARE THE STRENGTH OF THE STORMS
MONDAY AFTERNOON AND THE OVERALL COVERAGE OF STORMS LATER IN THE
WEEK AND FOR THE FOURTH. BROAD TROUGHING WILL BE IN PLACE OVER MUCH
OF THE EASTERN CONUS WITH A STRONG RIDGE OVER THE WEST.

MONDAY THROUGH TUESDAY...A SURFACE RIDGE WILL CONTINUE TO SLIDE TO
THE EAST OF THE AREA THROUGH THE DAY MONDAY. AS THIS HAPPENS...A
COLD FRONT AND COLLOCATED UPPER LEVEL SHORTWAVE WILL SLIDE INTO THE
WESTERN U.P. THE BIG QUESTION IS THE AMOUNT OF INSTABILITY THAT WILL
BE AROUND TO ALLOW SOME OF THESE STORMS TO BECOME SEVERE. TIMING OF
THE FRONT WOULD BE FAVORABLE FOR MAXIMUM INSTABILITY AS MANY OF THE
MODELS PLACE THE FRONT OVER THE WEST TO CENTRAL U.P. DURING PEAK
HEATING MONDAY AFTERNOON. THE 00Z/28 GFS IS STILL THE MOST
AGGRESSIVE WITH MUCAPE VALUES IN THE 2000-3000 J/KG RANGE WHILE THE
GENERAL CONSENSUS OF THE REMAINING MODELS WOULD KEEP IT AT A BIT
MORE MODEST AT 1000 TO 1500 J/KG...GENERALLY CONFINED TO THE
INTERIOR WEST AND ALONG THE WI BORDER. SHEAR VALUES ARE FAIRLY WEAK
FOR ANY WIDESPREAD ORGANIZED SEVERE WEATHER...WITH DEEP LAYER SHEAR
VALUES GENERALLY ON THE ORDER OF 15 TO 20 KTS. THE MOST LIKELY MODE
INITIALLY WOULD BE PULSE THUNDERSTORMS WITH A FEW ISOLATED SEVERE
STORMS IN THE NORTHWEST FLOW. THE MAIN THREATS WOULD LIKELY BE
MARGINALLY SEVERE HAIL AND STRONG WIND GUSTS WITH A BIT DRIER AIR
BELOW 800MB. THE COLD FRONT AND SHORTWAVE WILL CONTINUE ACROSS THE
U.P. THROUGH MONDAY NIGHT...REACHING THE EASTERN U.P. BY 06Z
TUESDAY. THIS WILL KEEP CONTINUED CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE AREA THROUGH THIS TIME
PERIOD...HOWEVER...ANY SEVERE POTENTIAL WILL LIKELY DIMINISH WITH
LOSS OF DAYTIME HEATING. AS THE FRONT SHIFTS EAST TUESDAY...THE EAST
HALF OF THE U.P. WILL CONTINUE TO BE UNDER THE TROUGH AXIS KEEPING
SLIGHT CHANCES OF RAIN SHOWERS IN THE FORECAST IN THE MORNING.
TUESDAY AFTERNOON...THIS WAVE WILL SLIDE EASTWARD AND A SURFACE
RIDGE WILL SLIDE INTO THE WEST HALF OF THE U.P. EFFECTIVELY SHIFTING
MOST OF THE PRECIPITATION OUT OF THE AREA. CLOUD COVER WILL LIKELY
LINGER EVEN AFTER THE RAIN DIMINISHES WITH MOISTURE LINGERING BEHIND
THE SYSTEM.

TUESDAY NIGHT THROUGH THURSDAY...THE AFOREMENTIONED DRY HIGH
PRESSURE SYSTEM WILL CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES
THROUGH THIS TIME PERIOD. THIS WILL KEEP MAINLY LIGHT WINDS AND
MOSTLY CLEAR SKIES IN THE FORECAST. THE LIGHT WINDS...CLEAR SKIES
AND GENERAL TROUGHING OVER THE AREA WILL ALLOW TEMPERATURES TO FALL
BELOW NORMAL TUESDAY NIGHT AND WEDNESDAY NIGHT. OVERNIGHT LOWS WILL
LIKELY FALL INTO MID 40S FOR THE INLAND LOCATION WITH A FEW OF THE
COLDER SPOTS POSSIBLY SEEING UPPER 30S. TO PUT IT IN
PERSPECTIVE...NORMAL LOWS THIS TIME OF YEAR ARE IN THE LOW 50S.

THURSDAY NIGHT THROUGH THE EXTENDED...MODELS HAVE THE NEXT LOW
PRESSURE SYSTEM AND UPPER LEVEL WAVE SLIDING ACROSS CENTRAL CANADA
THURSDAY NIGHT...REACHING HUDSON BAY AROUND 12Z FRIDAY. A COLD FRONT
EXTENDING SOUTH FROM THE LOW WILL PUSH CLOSER TO THE WESTERN U.P.
FRIDAY MORNING AND INTO THE EASTERN U.P. BY SATURDAY MORNING. ALONG
AND AHEAD OF THE FRONT...SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE...ESPECIALLY DURING THE DAY FRIDAY. MODELS ARE GENERALLY
PUSHING THE COLD FRONT EAST OF THE AREA BY THE FOURTH OF JULY
ALLOWING FOR DRIER CONDITIONS AND COOLER AIR. WILL HAVE TO SEE IF
THE WAVE SLIDES FAR ENOUGH EAST TO KEEP SHOWERS FROM LINGERING
DURING THE DAY SATURDAY. AT THIS POINT WILL STICK WITH A CONSENSUS
OF THE MODELS.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 727 AM EDT SUN JUN 28 2015

VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST
PERIOD. DAYTIME HEATING AND RESULTING INSTABILITY MAY TRIGGER
ISOLD/SCT -SHRA/TSRA THIS AFTN/EVENING...MAINLY NEAR LAKE BREEZE
BOUNDARIES. THERE IS THE NORMAL UNCERTAINTY IN LOCATION/COVERAGE OF
CONVECTION...BUT AT THIS POINT...IT APPEARS POTENTIAL IS SUFFICIENT
TO WARRANT A VCSH MENTION AT ALL TERMINALS...THOUGH KIWD/KSAW
PROBABLY HAVE A BETTER POTENTIAL FOR VCSH DUE TO LAKE BREEZE
BOUNDARIES PROGRESSING INTO BETTER INSTABILITY.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 308 AM EDT SUN JUN 28 2015

LIGHT WINDS BELOW 20 KNOTS ARE EXPECTED THROUGH THE ENTIRE FORECAST
PERIOD. PATCHY FOG WILL PERSIST ACROSS THE LAKE THROUGH TUE MORNING
AS A RELATIVELY MOIST AIRMASS REMAINS OVER THE REGION.
&&

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

$$

SHORT TERM...07
LONG TERM...KEC
AVIATION...07
MARINE...07


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