Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Graphics & Text | 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 KMPX 121154
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
654 AM CDT SAT JUL 12 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 248 AM CDT SAT JUL 12 2014

IT`S WARM AND MUGGY ACROSS THE FORECAST AREA THIS MORNING...BUT SO
FAR THE HEAVY RAIN HAS REMAINED JUST TO THE SOUTH AND WEST
ACROSS SD/NE/IA. THIS SHOULD CHANGE OVER THE NEXT SEVERAL HOURS AS
MORE ACTIVITY IS EXPECTED TO FORM FARTHER NORTHEAST...ACROSS
SOUTHERN MINNESOTA. THE DEWPOINTS ARE EXPECTED TO SLOWLY FALL
TODAY...BUT THERE WON`T BE A DRAMATIC CHANGE IN THE AIRMASS
LOCALLY UNTIL NORTHWEST FLOW DEVELOPS ON SUNDAY.

WELL YOU REALLY WOULDN`T KNOW IT...BUT THERE IS A SLOW MOVING COLD
FRONT CREEPING SOUTHEAST ACROSS MINNESOTA EARLY THIS MORNING.
TEMPS AND DEWPOINTS ACROSS PORTIONS OF NORTHERN MN ARE 5-15
DEGREES COOLER THAN THEY WERE AT THIS TIME FRIDAY MORNING. THE
WIDESPREAD THUNDERSTORMS OFF TO OUR SOUTH AND WEST ARE CLOSER TO
THE SURFACE WARM FRONT IN AN AREA OF GOOD MID-LEVEL WARM ADVECTION
AND FGEN. THERE ARE ALSO PWATS NEAR 2" AND GOOD 850-300MB
THICKNESS DIFFLUENCE ACROSS IA...SO THERE IS A LOT WORKING IN
FAVOR FOR HEAVY RAIN IN AREAS TO OUR SOUTH. THAT BEING
SAID...SOUTHERN MN SHOULD SEE A SLIGHT INCREASE IN 925-850MB
MOISTURE TRANSPORT LATE THIS MORNING WITH MORE OF A SOUTHWEST
ORIENTATION TO THE LOW LEVEL FLOW VECTORS /THEY`VE BEEN NEAR ZERO
OR NORTH MOST OF THE NIGHT/. THERE IS ALSO A WEAK SHORTWAVE AND PV
FEATURE LOCATED IN ND/SD EARLY THIS MORNING...WHICH IS RESPONSIBLE
FOR THE CONVECTION FROM PIERRE, SD BACK TOWARD THE BLACK HILLS.
THIS FEATURE SHOULD MAKE IT TO THE SD/MN BORDER BY AROUND
15Z...WHICH COULD THEN KICK OFF MORE THUNDERSTORMS LATE THIS
MORNING AND INTO THE AFTERNOON. IN THE MEANTIME...WE ARE ALREADY
SEEING ACTIVITY IN SD TRANSLATE FARTHER EAST AND APPROACH THE
STATE LINE...NOT TO MENTION A COUPLE SHOWERS AND ENHANCED CUMULUS
DEVELOPMENT GOING UP ALONG THE SLOW MOVING COLD FRONT IN
MINNESOTA. THE SIGNAL FOR WIDESPREAD HEAVY RAIN OR EVEN WIDESPREAD
RAIN ISN`T GREAT TODAY...BUT THERE IS STILL PLENTY OF MOISTURE
AROUND AND ENOUGH FORCING TO JUSTIFY 40-70% RAIN ACROSS THE
FORECAST AREA. WE ARE SIMPLY NOT EXACTLY SURE WHICH FORCING
MECHANISM WILL DOMINATE AND AT WHAT TIME. THE AVAILABLE CAM
GUIDANCE OVERNIGHT...DOES SUGGEST A COUPLE DISTINCT AREAS OF
CONVECTIVE INITIATION ACROSS THE FORECAST TODAY /ONE NORTH AND ONE
SOUTH/...BUT THERE IS CONSIDERABLE DIFFERENCES IN TIMING AND
PLACEMENT...SO IT IS DIFFICULT TO INCLUDE HIGHER THAN 70-75%
CHANCE OF RAIN AT ANY ONE LOCATION GIVEN THE UNCERTAINTY. THUNDER
DOES SEEM MUCH MORE LIKELY ACROSS SOUTHERN MN WHEN COMPARED TO
WHAT IS EXPECTED IN CENTRAL MN AND EVEN WEST CENTRAL MN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 248 AM CDT SAT JUL 12 2014

THE PERIOD WILL BEGIN WITH A CDFNT HAVING JUST SANK TO THE S OF
THE MPX CWFA...AND THIS WILL BEGIN THE POTENT CAA ADVERTISED FOR
THE N-CENTRAL CONUS OVER THE PAST SEVERAL DAYS. WHILE THE CDFNT
DROPS FURTHER S AND E DURG THE DAY SUN AND SUN NIGHT...A DEEP UPR
LVL CUTOFF LOW WILL DROP S FROM CENTRAL CANADA INTO THE GRT LKS
SUN NIGHT INTO MON. THERE WILL BE ENOUGH SEPARATION BETWEEN BOTH
FEATURES SUCH THAT A DRY DAY ON SUN FOR THE ENTIRE CWFA LOOKS IN
ORDER. HOWEVER...AS THE UPR LOW NEARS...SEVERAL SHTWV TROUGH AXES
WILL ROTATE ARND THE WRN FRINGES OF THE UPR LOW. IN ADDITION...A
WEAK POST-FRONTAL SFC TROUGH WILL ALSO DROP THRU THE REGION ON
MON...ALLOWING FOR SCATTERED RAIN SHWRS TO DEVELOP ACRS THE AREA.
AS THE UPR LOW PULLS AWAY FROM THE AREA MON NIGHT INTO TUE...THE
POTENTIAL FOR PRECIP WILL ALSO SHIFT OFF TO THE E. THUS LEAVING
THE MAIN STORY TO BE THE DROP IN TEMPERATURES. H85 TEMPS STILL
LOOK TO DROP TO THE 4 TO 6 DEG C RANGE...WELL BELOW NORMAL FOR
MID-JULY...AND THIS WILL TRANSLATE TO SFC TEMPS ARND 15 DEGREES
BELOW NORMAL. THE COLDEST AIR WILL DROP THRU THE REGION SUN NIGHT
THRU TUE NIGHT...WHERE HIGHS WILL ONLY HIT THE 60S WITH LOWS AS
FAR DOWN AS THE LWR 50S AND POTENTIALLY SOME UPR 40S IN NORMALLY
COLDER LOCATIONS. TEMPS DO LOOK TO MODERATE GOING INTO THE MID-TO-
LATE WEEK PERIOD AND THIS WILL BE ACCOMPANIED BY EXTENSIVE HIGH
PRES THAT WILL KEEP PRECIP AWAY FROM THE REGION STARTING TUE
NIGHT.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 641 AM CDT SAT JUL 12 2014

THUNDERSTORMS ARE EXPECTED TODAY ACROSS PORTIONS OF SOUTHERN
MINNESOTA AND WEST CENTRAL WISCONSIN. AS IS THE CASE WITH MOST
THUNDERSTORM EVENTS...WE ARE NOT EXACTLY SURE WHERE AND HOW LONG
THUNDER WILL LAST AT ANY GIVEN POINT. IN GENERAL...WE EXPECT
MORNING ACTIVITY TO CONTINUE AND EXPAND EAST /LIKELY INCREASING IN
COVERAGE/. THEN WE EXPECT A BIT OF A BREAK BEFORE REDEVELOPMENT
THIS AFTERNOON IN EAST CENTRAL MN AND WESTERN WI.

KMSP...
THAT STORM 20 MILES NW OF THE AIRPORT IS SLOWLY /VERY SLOWLY/
DEVELOPING S-SE WITH TIME...SO IF IT HOLDS TOGETHER IT WILL BE
REASONABLY CLOSE TO THE AIRPORT BY AROUND 13Z. IT`S MOVING SO
SLOW...THAT IF IT DOES MAKE IT TO THE AIRPORT IT WILL LIKELY HANG
AROUND FOR AWHILE. THERE SHOULD BE AFTERNOON STORMS...MOST OF THE
AVAILABLE WEATHER MODELS KEEP THIS ACTIVITY JUST NORTH OF THE
AIRPORT. IT WILL BE CLOSE THOUGH.

/OUTLOOK FOR KMSP/
SUN...VFR. NW WINDS 10-15 KTS.
MON...MVFR PSBL WITH CHC OF SHRA/TSRA. NW WINDS 15-30 KTS.
TUE...VFR. NW WINDS 10-15 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

SHORT TERM...CLF
LONG TERM...JPC
AVIATION...CLF






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