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FLUS43 KFSD 181020
HWOFSD

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
519 AM CDT SAT MAY 18 2013

SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-
IAZ001>003-012>014-020>022-031-032-NEZ013-014-191200-
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-
519 AM CDT SAT MAY 18 2013

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
SCATTERED THUNDERSTORMS WILL MOVE INTO THE LOWER BRULE AREA VERY
EARLY THIS MORNING...AND WILL LIKELY PRODUCE SOME WIND GUSTS TO
40 TO 50 MPH ALONG WITH POTENTIAL FOR SMALL HAIL.

AFTER THE EARLY DAY STORMS...MUCH OF THE DAY IS EXPECTED TO
REMAIN QUIET...UNTIL A SMALL CHANCE FOR THUNDERSTORMS WEST OF THE
JAMES VALLEY STARTS LATE THIS AFTERNOON. THE CHANCE FOR
THUNDERSTORMS WILL INCREASE DURING THE EVENING FROM THE JAMES
VALLEY WESTWARD. ANY STORMS THAT DO FORM WILL BE CAPABLE OF HAIL
TO GOLF BALL SIZE AND WIND GUSTS TO 70 MPH. AN ISOLATED TORNADO
WILL BE POSSIBLE TOWARD SOUTH CENTRAL SOUTH DAKOTA. STORMS WILL
BECOME MORE WIDESPREAD TOWARD MIDNIGHT WITH AN ORGANIZED SYSTEM
LIKELY MOVING NORTHEAST OUT OF NEBRASKA. AS STORMS REACH
INTERSTATE 29...THE THREAT WILL GRADUALLY TRANSITION FROM LARGE
HAIL TO HALF DOLLAR SIZE ALONG WITH DAMAGING WIND...TO MAINLY
DAMAGING WIND OF 60 TO 80 MPH...BEFORE STORMS WEAKEN WELL AFTER
MIDNIGHT TOWARD HIGHWAY 71.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE SEVERE WEATHER THREAT ON SUNDAY WILL HAVE SOME DEPENDENCE ON
THE IMPACT OF CONVECTION FROM SATURDAY NIGHT. WHILE UNCERTAINTY
REMAINS AS TO THE LOCATION MOST LIKELY TO HAVE A SEVERE WEATHER
THREAT BY MID AFTERNOON AND THROUGH THE EVENING HOURS ON
SUNDAY...THERE IS A MUCH GREATER PROBABILITY FOR LOCATIONS EAST
OF THE JAMES RIVER...AND ESPECIALLY FOR AREAS EAST OF YANKTON TO
SIOUX FALLS LINE. LARGE HAIL UP TO 2 INCHES IN DIAMETER...ALONG
WITH A SMALL THREAT FOR AN ISOLATED TORNADO WILL EXIST FROM THE
LOWER MISSOURI VALLEY THROUGH NORTHWEST IOWA. DAMAGING WINDS OF
60 TO 80 MPH WILL ALSO INCREASE IN LIKELIHOOD BY THE EVENING
HOURS AS STORMS SPREAD EAST THROUGH NORTHWEST IOWA. A LOWER END
LARGE HAIL AND WIND THREAT WILL EXIST NORTH OF INTERSTATE 90.
SOME VERY HEAVY RAINFALL WILL ALSO BE POSSIBLE...AND FLASH
FLOODING WILL BE A THREAT WITH STORMS THROUGH THE EVENING ACROSS
NORTHWEST IOWA AND INTO SOUTHWEST MINNESOTA.

THE CHANCE OF THUNDERSTORMS WILL CONTINUE ACROSS THE AREA ON
MONDAY...ESPECIALLY DURING THE AFTERNOON AND EARLY EVENING. WHILE
SEVERE STORMS PRODUCING DAMAGING WIND AND HAIL ARE NOT
EXPECTED... THERE MAY BE A LOW END THREAT FOR A WEAK TORNADO SPIN
UP OR FUNNEL CLOUD.  THIS THREAT MAY CONTINUE TUESDAY AFTERNOON
ACROSS PARTS OF NORTHWEST IOWA AND SOUTHWEST MINNESOTA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE LIKELY AFTER 6 PM WEST OF THE JAMES
RIVER...
AND AFTER 11 PM EAST OF INTERSTATE 29.

&&

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

$$