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000
FXUS63 KMPX 160941
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
415 AM CDT SUN JUN 16 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 414 AM CDT SUN JUN 16 2013

EARLY MORNING WATER VAPOR IMAGERY SHOWS A WELL DEFINED SHORTWAVE
TROUGH SPINNING OVER SASKATCHEWAN AND MANITOBA...WITH SURFACE OBS
ILLUSTRATING AN ATTENDANT ELONGATED TROUGH STRETCHING EASTWARD
ACROSS CENTRAL ONTARIO. THE ASSOCIATED COLD FRONT WILL GRADUALLY
PASS ACROSS THE AREA LATER TODAY AND TONIGHT. A RELATIVELY THIN
RIBBON OF MOISTURE ADVECTION AND INSTABILITY IS FORECAST TO DEVELOP
IN ADVANCE OF THE FRONT IN CONJUNCTION WITH DIURNAL HEATING. SAID
MOISTURE AND INSTABILITY COULD BE SUFFICIENT TO GENERATE SCATTERED
SHOWERS AND THUNDERSTORMS BY MID AFTERNOON...ALTHOUGH THE SLIGHTLY
HIGHER PROBABILITIES ARRIVE AFTER 23Z AS THE 700-600MB FORCING WITH
THE AFOREMENTIONED SHORTWAVE ARRIVES.

AFTER THE FOG OVER WEST CENTRAL WI AND BORDERING AREAS OF EAST
CENTRAL MN DISSIPATES...INCREASING WESTERLY WINDS SHOULD HELP RALLY
TEMPERATURES TO ABOVE NORMAL VALUES INTO THE UPPER 70S TO MID 80S.
TEMPERATURES TONIGHT SHOULD ALSO BE ON THE WARM SIDE...AND GENERALLY
IN THE 55 TO 60 DEGREE RANGE.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 414 AM CDT SUN JUN 16 2013

BACK DOOR COLD FRONT DESCENDING INTO THE CWA FROM SOUTHWESTERN
ONTARIO...WILL BE THE CATALYST FOR ANOTHER CONVECTIVE ROUND OF
PCPN FOR MUCH OF THE DAYLIGHT HOURS ON MONDAY. GFS40 A LITTLE
MORE AGGRESSIVE WITH COVERAGE OF SAME OVER THE FA COMPARED TO
THE EUROPEAN. CONSIDERING GFS40`S HANDLING OF SUNDAY`S PCPN
...DECIDED IT WILL BE BEST SOLUTION FOR REMAINDER OF FORECAST
PACKAGE. BEST UPPER LEVEL SUPPORT AND LOW LEVEL FORCING SHOULD
OCCUR OVER NORTHEASTERN HALF OF CWA FOR THIS EVENT...THUS HAVE
INCREASED POPS ACCORDINGLY OVER THIS REGION. A RARE DRY PERIOD
SHOULD SHAPE UP OVER MN/WESTERN WI FROM MON NIGHT INTO MUCH OF WED
MORNING. INTRODUCED SLIGHT POPS FOR WED AFTN AS INSTABILITY INCREASES
ON BACK SIDE OF 1022MB HIGH PRESSURE SLIDING EAST INTO WI AND WESTERN
GREAT LAKES.

SLOW MOVING SURFACE CYCLONE OVER CENTRAL MT WED MORNING WILL
SLOWLY PROCEED EAST INTO WESTERN NODAL BY THU/12Z...WITH ATTACHED
COLD FRONTAL BOUNDARY EXTENDING SOUTH INTO WESTERN NE. CUT OFF
50H LOW OVER PACIFIC NORTHWEST WILL DIG MID LEVEL TROUGH INTO
NORTHERN BAJA INTO FRIDAY MORNING...INITIATING HIGHER AMPLITUDE
MID LEVEL TROUGH OVER MUCH OF UPPER MIDWEST. ALTHOUGH PCPN CHANCES
SHOULD SLOWLY RAMP UP FROM WEDNESDAY NIGHT INTO SATURDAY...TEMPERATURES
ASSOCIATED WITH THIS FEATURE WILL FINALLY REACH INTO THE LOW TO MIDDLE
80S OVER MUCH OF THE FA FROM WED-SAT. WITH MODERATE SOUTHERLY FLOW
AND 850MB TEMPS SHOOTING UP INTO THE PLUS 18-20 DEGREE RANGE BY
LATE FRIDAY...COULD EASILY ENCOUNTER SOME UPPER 80S TO NEAR 90
DEGREE READINGS THIS DAY. HOWEVER...WITH INCREASING CLOUD AND
PCPN TRENDS...DECIDED BEST COURSE WAS TWEAKING TEMPS A DEGREE
OR TWO HIGHER FOR FRI-SAT. EUROPEAN PROJECTS FASTER SOLUTION
IN BRINGING SURFACE CYCLONE THROUGH MUCH OF FA BY SATURDAY EVENING
COMPARED WITH THE GFS40. BOTH HOWEVER...DEPICT MODERATE TO HEAVY
PCPN (0.75 TO 1.2 INCHES) OF QPF OVER MUCH OF CWA DURING THE
SAT/SAT EVE TIME FRAME. RAISED POPS A TAD TO ACCOUNT FOR THIS
SIMILARITY ON SATURDAY. ALTHOUGH THREAT FOR PCPN DROP WITH PASSAGE
OF CYCLONE AND ATTACHED COOL FRONT BY SATURDAY NIGHT...INSTABILITY
ASSOCIATED WITH 50H TROF FROM CLOSED LOW OVER SOUTHERN CANADA SHOULD
GENERATE AT LEAST CHANCE POPS SUNDAY AND MONDAY. AFTER THAT LOOK
FOR ANOTHER SHORT LIVED MID LEVEL RIDGE TO FORM OVER NORTHERN
GREAT PLAINS TUE-THUR AS ANOTHER STRONG GULF OF ALASKA CYCLONE
DIGS SOUTH NEAR THE ALEUTIANS.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1110 PM CDT SAT JUN 15 2013

AREAS OF FOG HAVE DEVELOPED ACROSS WRN WI RIGHT AFTER SUNSET
SATURDAY EVENING. VISIBILITIES HAVE DROPPED TO LESS THAN ONE MILE
ON A LOCALIZED BASIS AT TAF ISSUANCE TIME. THINK RNH AND EAU CAN
SEE AT LEAST TEMPORARY REDUCTIONS TO 1/4SM DURING MOST OF THE
OVERNIGHT. THE FOG IS LIKELY TO REMAIN SHALLOW DUE TO ABUNDANT DRY
AIR ALOFT...SO CONDITIONS MAY BE QUITE VARIABLE. CONDITIONS WILL
RAPIDLY IMPROVE AROUND 12Z OR 13Z. VFR CONDITIONS ARE EXPECTED
ELSEWHERE THROUGH THE PERIOD...ALTHOUGH THERE MAY BE PATCHY FOG AS
FAR WEST AS STC TONIGHT. IT SHOULD BE PATCHY ENOUGH TO PRECLUDE
MENTION IN THE MSP/STC TAF HOWEVER.

KMSP...VFR CONDITIONS EXPECTED THROUGH THE PERIOD...ALTHOUGH
THERE IS AN OUTSIDE CHANCE AT MVFR VSBYS LATE TONIGHT. AM NOT
CONFIDENT ENOUGH TO INCLUDE IT IN THE TAF...BUT CONDITIONS WILL BE
MONITORED.

/OUTLOOK FOR KMSP/
MON...CHANCE OF MVFR CONDS AND TSRA...MAINLY IN THE MORNING. NW
WINDS 10KTS.
TUE...VFR. LGT AND VRB WINDS.
WED...VFR. S WINDS 5 KTS.


&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...DENSE FOG ADVISORY UNTIL 8 AM CDT THIS MORNING FOR WIZ014>016-
     023>028.

&&

$$

SHORT TERM...LS
LONG TERM...AJZ
AVIATION...BORGHOFF