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000
NOUS43 KGRB 171419
PNSGRB
WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-171800-

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GREEN BAY WI
920 AM CDT WED APR 17 2013

...TORNADO AND SEVERE WEATHER AWARENESS WEEK IS APRIL 15-19...

...SIGNATURE OF STRAIGHT-LINE WINDS...
STRAIGHT-LINE WINDS ARE OFTEN RESPONSIBLE FOR MOST OF THE WIND DAMAGE
ASSOCIATED WITH A THUNDERSTORM. THESE WINDS ARE OFTEN CONFUSED WITH
TORNADOES BECAUSE OF SIMILAR TYPES OF DAMAGE AND WIND SPEEDS. HOWEVER
THE STRONG DAMAGING WINDS ASSOCIATED WITH STRAIGHT-LINE WINDS ARE
UNLIKE THE ROTATING WINDS OF A TORNADO. IF YOU WERE TO SURVEY THE
DAMAGE PATTERN LEFT BY STRAIGHT-LINE WINDS...YOU WOULD SEE DEBRIS...
SUCH AS UPROOTED TREES...LAID OUT IN NEARLY PARALLEL ROWS.

...DOWNBURST BASICS...
DOWNBURSTS ARE ONE EXAMPLE OF DAMAGING STRAIGHT LINE WINDS. A
DOWNBURST IS A SMALL AREA OF RAPIDLY DESCENDING RAIN AND RAIN-COOLED
AIR BENEATH A THUNDERSTORM. WIND SPEEDS IN SOME OF THE STRONGER
DOWNBURSTS CAN REACH 100 MPH OR GREATER WHICH IS SIMILAR TO
THAT OF A STRONG TORNADO.

THE WINDS PRODUCED FROM A DOWNBURST OFTEN TRAVEL IN ONE
DIRECTION...AND THE WORST DAMAGE IS USUALLY ON THE FORWARD SIDE OF
THE DOWNBURST. HOWEVER...SOMETIMES THEY WILL HIT THE GROUND AND
SPREAD OUT IN ALL DIRECTIONS. IN THAT CASE...DAMAGE WILL TEND TO FAN
OUT FROM A LARGE CENTER POINT.

...DERECHOS...
ANOTHER CATEGORY OF STRAIGHT-LINE WINDS COMMON TO THE MIDWEST ARE
KNOWN AS DERECHOS. DERECHOS USUALLY OCCUR IN THE MIDWESTERN STATES
IN THE LATE SPRING AND SUMMER.

DERECHOS ARE CREATED BY THE MERGING OF MANY THUNDERSTORM CELLS...
PARTICULARLY NEAR A WARM FRONT...INTO A LARGE CLUSTER OR A SOLID SQUALL
LINE EXTENDING FOR MANY MILES PERPENDICULAR TO THE WARM FRONT. THE
LENGTH OF THE LINE CAN REACH 100 MILES OR MORE.

IN EXTREME CASES...THESE STORMS CAN CREATE MAXIMUM WIND GUSTS OVER 120
MPH. NOT ONLY CAN A DERECHO CONTAIN INCREDIBLY STRONG STRAIGHT-LINE
WINDS...IT IS ALSO CAPABLE OF PRODUCING SMALL TORNADOES. AS A RESULT...
THESE TYPES OF SYSTEMS CAN BE EXTREMELY DANGEROUS AND PRODUCE WIDESPREAD
DAMAGE.

...EXTREME THUNDERSTORM WIND FREQUENCY...
ON AVERAGE...WISCONSIN EXPERIENCES WIND GUSTS OF 75 MPH OR HIGHER ON 5
DAYS EACY YEAR. WISCONSIN EXPERIENCES A THUNDERSTORM WIND GUST OF 100
MPH OR MORE ON ONE DAY EVERY TWO YEARS.

...EXAMPLES OF POWERFUL DOWNBURSTS...
ON JULY 1 2012...A POWERFUL SQUALL LINE RIPPED THROUGH NORTHWESTERN
WISCONSIN IN THE BURNETT COUNTY AREA WITH GUSTS OF 100 TO 120 MPH.
THOUSANDS OF TREES WERE LEVELED AND NUMEROUS POWER-LINES WERE
KNOCKED OVER.  VEHICLES...CAMPER TRAILERS...AND BOATS WERE FLIPPED
OVER BY THE WIND OR DAMAGED BY TREE DEBRIS.  SEVERAL HOMES SUSTAINED
SIDING OR ROOF DAMAGE.

ON SEPTEMBER 2 2011...A POWERFUL CLUSTER OF STORMS RAKED CENTRAL AND
EAST-CENTRAL WISCONSIN WITH WIND GUSTS OF 80 TO 95 MPH.  NUMEROUS
BUILDINGS WERE DAMAGED AND OVER 60000 CUSTOMERS LOST ELECTRICITY.
APPLETON WAS HIT HARD WITH OVER 5.3 MILLION DOLLARS IN DAMAGE.  MANY
TREES WERE UPROOTED AND SEVERAL BUILDINGS WERE DAMAGED.

ON JUNE 21 2011...A SQUALL LINE TORE NORTHEAST THROUGH WAUKESHA
COUNTY WITH WIND GUSTS UP TO 100 TO 110 MPH. THOUSANDS OF TREES WERE
UPROOTED OR DAMAGED AND MANY POWER-LINES CAME DOWN. ONE TRUCK ON
INTERSTATE-94 WAS BLOWN OVER...AND ONE PERSON WAS INJURED BY FLYING
DEBRIS.

----------------------------------------------------------------

ALWAYS KEEP IN MIND THAT MAJOR DAMAGE TO A HOME...BUILDING OR ANY
PERSONAL PROPERTY CAN BE CAUSED BY A VARIETY OF DIFFERENT STRAIGHT-
LINE WIND EVENTS. ALWAYS TAKE COVER WHEN STRONG THUNDERSTORM WINDS
THREATEN.

AS WITH ANY SEVERE WEATHER...STAY TUNED TO NOAA ALL HAZARDS WEATHER
RADIO OR YOUR LOCAL TV OR RADIO STATIONS FOR THE LATEST FORECAST AND
ANY SEVERE WEATHER WATCHES OR WARNINGS.

FOR ADDITIONAL SEVERE WEATHER INFORMATION AND THE LATEST FORECASTS AND
WARNINGS FOR NORTHEAST WISCONSIN...VISIT: WWW.WEATHER.GOV/GRB

$$
JKL
WEATHER.GOV/GRB