Severe Thunderstorm Warning 537, NWS Sioux Falls, SD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
235 PM CDT TUE SEP 14 2004

.DISCUSSION...

CURNT SHWRS AND TSTMS OVER SERN PART OF AREA AS WELL AS ACTVTY
APPCHG WRN PART OF FCST AREA ARE BARELKY A BEGINNING. A CONTINUATION
OF ERYR DISCUSSED FACTORS SUCH AS WRM/STNRY FNT SERN CRNR OF
AREA...GREAT CONTRAST AND CONVERGNCE IN FVRBL WND FIELDS...AND RICH
AND DEEP MOISTR SHUD MAKE FOR A HVY RAIN EVENT OVER SERN PART OF
AREA TNGT. CONTINUING FLOOD WATCH A NO BRAINER ESPLY WHEN U ADD THE
CURNTLY WET CONDS. DESPITE THE FOCUS OF HVY RAIN AND FLOOD POTENTL
IN THE SE...MAINLY NWRN IA...REST OF CWA WILL NOT BE LEFT OUT OF
DECENT SHWR/TSTM CVRG TNGT AS STG SHRTWV MOVES INTO AREA EVEN THO
AMOUNTS WILL BE QUITE A BIT LWR TO W AND N.

ACTVTY SHUD MOVE OUT GRDLY FROM THE W WED...THO SOME DECENT RAINFALL
STILL PSBL FAR E MAINLY IN MRNG. CLRNG WILL BEGIN FROM THE W WED
AFTN AND SHUD SPRD RPDLY OVER AREA WED NGT. WITH THE CLRNG SKIES AND
LGT WNDS WE MAY HAVE TO WATCH OUT FOR SIGNIFCNT RADIATION FOG EVENT
LATE WED NGT/ERY THU MRNG. WILL HOLD OFF FOR NOW TIL DETAILS OF
CLRNG AND LGT WNDS BCM MORE SETTLED.

THIS CLRNG SHUD USHER IN A DRY PD WHICH SHUD CONT TIL WE GET TO NEAR
END OF FCST PD. AT THAT POINT APPCH OF LARGE SCALE TROF WILL BRING A
THREAT OF SHWRS OR TSTMS LAST DAY OR TWO...ALG WITH COOLING FOR TUE
ASSUMING FNT COMES THRU AS MOST MODELS SHOW. GFS LOOKS A LTL TOO
FAST ON TROF/FNT COMPARED WITH OTHER MODELS.

HAVE BEEN FAIRLY MODERATE ON WARMNG OVER THE WEEKEND THO CERTAINLY
GOING WRMR THAN WE HAD. IF AIR STAYS DRY ENUF WE CUD GET BACK TO
SEEING A FEW 90S...BUT WILL KEEP IN 80S FOR NOW.

&&

.FSD...WATCHES/WARNINGS/ADVISORIES...
SD...FLOOD WATCH    TNGT       XTRM SERN SD UNION CO
MN...FLOOD WATCH    TNGT       JACKSON CO
IA...FLOOD WATCH    TNGT       ALL OF NWRN IA XCP LYON CO
NE...FLOOD WATCH    TNGT       DIXON AND DAKOTA COS

&&

WILLIAMS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1147 AM CDT TUE SEP 14 2004

SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-
IAZ001>003-012>014-020>022-031-032-NEZ013-014-151200-
AURORA-BEADLE-BON HOMME-BROOKINGS-BRULE-BUENA VISTA IA-
CHARLES MIX-CHEROKEE IA-CLAY-CLAY IA-COTTONWOOD MN-DAKOTA NE-
DAVISON-DICKINSON IA-DIXON NE-DOUGLAS-GREGORY-HANSON-HUTCHINSON-
IDA IA-JACKSON MN-JERAULD-KINGSBURY-LAKE-LINCOLN-LINCOLN MN-
LYON IA-LYON MN-MCCOOK-MINER-MINNEHAHA-MOODY-MURRAY MN-NOBLES MN-
OBRIEN IA-OSCEOLA IA-PIPESTONE MN-PLYMOUTH IA-ROCK MN-SANBORN-
SIOUX IA-TURNER-UNION-WOODBURY IA-YANKTON-
1147 AM CDT TUE SEP 14 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA...
SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
THUNDERSTORMS WILL REDEVELOP NEAR A VERMILLION TO SPENCER IOWA
LINE AFTER 4 PM THIS AFTERNOON. SOME STORMS MAY BECOME SEVERE
LATE THIS AFTERNOON AND EARLY THIS EVENING ALONG AND SOUTH OF A
VERMILLION TO SPIRIT LAKE LINE. VERY HEAVY RAINFALL...HAIL THE
SIZE OF HALF DOLLARS AND WIND GUSTS TO 60 MPH ARE THE MAIN
THREATS. AN ISOLATED TORNADO WILL ALSO BE POSSIBLE ALONG AND JUST
SOUTH OF THIS FRONT. THE THREAT FOR TORNADOES WILL BE MAINLY
SOUTH OF A SIOUX CITY TO LINN GROVE LINE.

FLOODING...
THUNDERSTORMS THAT DEVELOP THIS AFTERNOON AND EVENING OVER
NORTHEAST NEBRASKA...NORTHWEST IOWA...FAR SOUTHEAST SOUTH DAKOTA
AND FAR SOUTHERN MINNESOTA WILL HAVE THE POTENTIAL TO PRODUCE
VERY HEAVY RAINFALL. SOME LOCATIONS COULD SEE AMOUNTS OF 2 TO 4
INCHES...WITH HOURLY RAINFALL RATES APPROACHING TWO INCHES. A FEW
RIVERS....CREEKS AND STREAMS COULD APPROACH BANKFULL AND URBAN
FLOODING WILL ALSO BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE LIKELY AFTER 500 PM CDT.

&&

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT
WWW.CRH.NOAA.GOV/FSD. THIS INCLUDES THE GRAPHICAL HAZARDOUS
WEATHER OUTLOOK.

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