503
FXUS63 KMPX 130832
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
332 AM CDT TUE AUG 13 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT TUE AUG 13 2013
VERY COOL TEMPS EARLY THIS MORNING IN THE WAKE OF A SFC TROUGH
THAT MOVED THROUGH THE REGION MONDAY AFTERNOON. 40S...AND A FEW
UPPER 30S WERE NOTED IN CENTRAL MN/EC MN AND PORTIONS OF WC WI AS
OF 3 AM. ALTHOUGH FOG WAS OCCURRING IN PORTIONS OF WC WI...THE
BULK OF THE LOWEST VSBYS WERE IN FAR NORTHERN WI WHERE TEMPS FELL
TO NEAR 40 DEGREES. THESE EARLY MORNING TEMPS...COMBINED WITH THE
CONTD COLD AIR ADVECTION TODAY...WILL LEAD TO AFTN TEMPS A FEW
DEGREES COOLER THAN ON MONDAY. MOST AREAS WILL BE IN THE LOW TO
MID 70S...WITH THE WARMEST AREAS IN THE SW.
NOT MUCH CHG THROUGH TONIGHT AS HIGH PRESSURE DOMINATES THE UPPER
MIDWEST. ANOTHER COOL NIGHT...WITH TEMPERATURES SLOWLY MODERATING
THIS WEEK.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE AUG 13 2013
RELATIVELY DRY FORECAST FOR THE EXTENDED...WITH TWO SPECIFIC TIMES
WITH PRECIP CHANCES FROM THURSDAY AFTERNOON INTO FRIDAY...AND THEN
AGAIN EARLY NEXT WEEK. AT THE START OF THE PERIOD PERSISTENT
SUBSIDENCE DOWNSTREAM OF THE UPPER LEVEL RIDGE AXIS WILL HAVE
RESULTED IN A BROAD AREA OF SURFACE HIGH PRESSURE ACROSS THE UPPER
MIDWEST. THIS WILL SET THE STAGE FOR LIGHT WINDS AND CLEAR SKIES ON
WEDNESDAY. ON THURSDAY AFTERNOON FORECAST MODELS HAVE A SHORTWAVE
CROSSING THE IDAHO PANHANDLE AND MOVING SOUTHEAST OVER THE HIGH
PLAINS INTO THE CORNBELT REGION. THIS WILL PRODUCE UPSLOPE
THUNDERSTORMS THAT WILL TRACK DOWN THE MISSOURI RIVER VALLEY. A
SECOND SHORTWAVE FARTHER NORTH WILL FOLLOW ON ITS HEALS...AND BE THE
FOCUS FOR A FEW SHOWERS AND THUNDERSTORMS ACROSS MINNESOTA AND
WISCONSIN THURSDAY NIGHT AND FRIDAY. STILL ONLY HAVE 20-30 POPS FOR
THIS SCENARIO AS THE FORCING WILL BE WEAK AND LOW LEVEL MOISTURE
WILL BE LIMITED. FORECAST SOUNDINGS SHOW SKINNY CAPE PROFILE WITH AN
UNCAPPED ENVIRONMENT BY FRIDAY AFTERNOON...SO HAVE THE MENTION OF
THUNDER. HOWEVER DEEP LAYER WIND SHEAR WILL BE A PALTRY 20KTS OR
LESS...SO COLD POOLS WILL LIKELY SPREAD OUT BENEATH THE UPDRAFTS AND
TERMINATE ANY CONVECTIVE CELLS BEFORE THEY BECOME CAPABLE OF
PRODUCING SEVERE WEATHER.
WARMER WEATHER WILL FOLLOW FOR THE WEEKEND AS THE THERMAL RIDGE
SPREADS ACROSS THE UPPER MIDWEST WITH SOUTHWEST FLOW AND H850 TEMPS
13-16C YIELDING SURFACE TEMPS IN THE LOW 80S. LATE ON SUNDAY THE GFS
GEM AND ECMWF 13.00 BRING A SHORTWAVE ACROSS THE NORTHERN
CONUS...WHICH WILL INTRODUCE PRECIP CHANCES ON MONDAY AS IT DRIVES A
COLD FRONT THOUGH THE REGION. THE ECMWF IS FARTHEST NORTH...WHICH
WOULD KEEP THE MAJORITY OF THE SHOWER/THUNDERSTORM ACTIVITY NEAR THE
INTERNATIONAL BORDER. HOWEVER GIVEN THE FAIRLY DESCENT AGREEMENT
BETWEEN THE LONG RANGE MODELS FEEL AT LEAST 20-30 POPS ARE WARRANTED
AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1045 PM CDT MON AUG 12 2013
FEW CONCERNS THIS CYCLE AS HIGH PRESSURE DOMINATES THE REGION.
SOME PATCHES OF SCT-BKN060-070 OVERNIGHT AND EARLY TUESDAY ACROSS
EASTERN MN AND WEST CENTRAL WI. THERE ALSO REMAINS THE THREAT FOR
FOG BETWEEN 09Z-13Z AT KEAU. THIS IS SOMEWHAT HEIGHTENED BY THE
FACT THAT THEY HAD A FEW HUNDREDTHS OF RAIN THIS PAST EVENING.
LIGHT NORTH TO NORTHEAST WINDS OVERNIGHT AND TUESDAY.
KMSP...VFR THROUGH THE PERIOD ALONG WITH N TO NE WINDS 5 TO 8
KTS.
/OUTLOOK FOR KMSP/
WED...VFR. WINDS W 5 KTS.
THU...VFR. WINDS SW 5 KTS.
FRI...VFR. SLIGHT CHANCE ISOLD SHRA/TS. WINDS S 8 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...JRB
AVIATION...RAH