September 20, 2007: Late Season Severe Weather Including a Tornado in Woodbury

September 20, 2007: Severe Weather, Including a Tornado Threat, to Afternoon Rush Hour in the Twin Cities

Environmental Setup | Woodbury, MN Tornado | Storm Reports | Autumn Severe Weather

Environmental Setup

A strong warm front for late September pushed northward across southern Minnesota during early Thursday. Warm, moist air surged northward south of this feature. Isolated severe thunderstorms tracked across western Minnesota during the morning. The front grew stronger during the afternoon and focused severe thunderstorms across central Minnesota during the latter afternoon and into the night, where an EF zero tornado occurred in the southwestern portion of Woodbury. Severe weather reports from September 20th can be found in text and graphical format below.

Surface Weather Map from 4pm on Sept 20, 2007

September 20, 2007 4pm Surface Weather Map

Woodbury, MN Tornado

...AN EF ZERO TORNADO OCCURRED IN WOODBURY ON EVENING OF SEPTEMBER 20 2007...

NATIONAL WEATHER SERVICE PERSONNEL FROM THE CHANHASSEN OFFICE
CONDUCTED A DAMAGE ASSESSMENT IN THE WOODBURY AREA THIS AFTERNOON.

THE DAMAGE IN WOODBURY WAS FOUND TO BE CAUSED BY AN EF ZERO TORNADO.
THE TORNADO TOUCHED DOWN IN THE SOUTHWEST CORNER OF WOODBURY ALONG
BAILEY ROAD AT APPROXIMATELY 6:30 PM...AND DISSIPATED JUST AS IT
REACHED WOODLANE DRIVE. THE TORNADO WAS ON THE GROUND FOR FOUR
TENTHS OF A MILE...AND ITS MAXIMUM WIDTH WAS 50 YARDS WIDE.

THE TORNADO CAUSED DAMAGE TO MULTIPLE TOWNHOUSES...TREES...AND ROAD
SIGNS. WHILE THE MAJORITY OF THE DAMAGE WAS BLOWN FROM NORTHEAST TO
SOUTHWEST...SOME CONVERGENT DAMAGE WAS ALSO NOTED. CONVERGENT DAMAGE
IS CONSISTENT WITH ROTATING WINDS IN A TORNADO.

FOR A LINK TO THE TORNADO RATING SCALE...OR ENHANCED FUJITA
SCALE...VISIT http://www.spc.noaa.gov/efscale

Storm Reports

Severe Weather Reports From September 20th, 2007

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
434 PM CDT FRI SEP 21 2007

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0822 AM     HAIL             BURR                    44.72N 96.28W
09/20/2007  M1.00 INCH       YELLOW MEDICINE    MN   FIRE DEPT/RESCUE

0855 AM     HAIL             DAWSON                  44.93N 96.05W
09/20/2007  M2.00 INCH       LAC QUI PARLE      MN   TRAINED SPOTTER

0920 AM     TSTM WND DMG     1 NE WATSON             45.02N 95.79W
09/20/2007                   CHIPPEWA           MN   CO-OP OBSERVER

            LARGE TREE DOWN.

1042 AM     TSTM WND DMG     BENSON                  45.32N 95.61W
09/20/2007                   SWIFT              MN   LAW ENFORCEMENT

            TWO TREES DOWN IN TOWN. ONE BLOCKING A STREET.

1042 AM     FLASH FLOOD      SAUK CENTRE             45.74N 94.96W
09/20/2007                   STEARNS            MN   LAW ENFORCEMENT

            ROADS ARE GETTIING BARRICADED AROUND TOWN...DUE TO
            FLOODING.

1042 AM     FLASH FLOOD      SAUK CENTRE             45.74N 94.96W
09/20/2007                   STEARNS            MN   TRAINED SPOTTER

            ROADS ARE GETTING BARRICADED AROUND TOWN...DUE TO
            FLOODING.

1042 AM     FLASH FLOOD      SAUK CENTRE             45.74N 94.96W
09/20/2007                   STEARNS            MN   TRAINED SPOTTER

            ROADS ARE GETTING BARRICADED AROUND TOWN...DUE TO
            FLOODING.

1125 AM     HAIL             4 S BELGRADE            45.39N 95.00W
09/20/2007  E0.88 INCH       KANDIYOHI          MN   LAW ENFORCEMENT

            RELAYED VIA HAM RADIO.

1135 AM     HAIL             BROOTEN                 45.50N 95.12W
09/20/2007  E0.88 INCH       STEARNS            MN   LAW ENFORCEMENT

            RELAYED VIA HAM RADIO.

1202 PM     HAIL             MELROSE                 45.68N 94.81W
09/20/2007  M0.75 INCH       STEARNS            MN   AMATEUR RADIO

            MEASURED 0.8 INCH DIAMETER.

1258 PM     HAIL             STARBUCK                45.61N 95.53W
09/20/2007  E1.00 INCH       POPE               MN   LAW ENFORCEMENT

0245 PM     TSTM WND DMG     SAUK RAPIDS             45.59N 94.17W
09/20/2007                   BENTON             MN   PUBLIC

            PARTS OF A FENCE AROUND GOLDEN SPIKE RACEWAY WERE DAMAGED
            BY WINDS.

0257 PM     TSTM WND DMG     ST STEPHEN              45.70N 94.28W
09/20/2007                   STEARNS            MN   AMATEUR RADIO

            20 INCH TREE DOWN.

0257 PM     TSTM WND DMG     ST STEPHEN              45.70N 94.28W
09/20/2007                   STEARNS            MN   AMATEUR RADIO

            PARTIAL BARN ROOF BLOWN OFF.

0259 PM     TSTM WND DMG     SARTELL                 45.62N 94.21W
09/20/2007                   STEARNS            MN   AMATEUR RADIO

            MULTIPLE ONE AND A HALF TO TWO FOOT TREES DOWN.

0304 PM     TSTM WND DMG     SARTELL                 45.62N 94.21W
09/20/2007                   STEARNS            MN   AMATEUR RADIO

            TIN OF MEDICAL BUILDING ROOF BLOWN OFF.

0410 PM     FLASH FLOOD      2 N SAUK CENTRE         45.77N 94.96W
09/20/2007                   STEARNS            MN   TRAINED SPOTTER

            4.85 INCHES RAIN SINCE 1000 AM. SPOTTER REPORTS ONE FOOT
            DEEP IN TOWN AT RAILROAD CROSSING.

0410 PM     TSTM WND DMG     ISANTI                  45.49N 93.25W
09/20/2007                   ISANTI             MN   PUBLIC

            20 INCH DIAMETER TREE DOWN ACROSS ROAD.

0415 PM     TSTM WND DMG     2 S MORA                45.85N 93.29W
09/20/2007                   KANABEC            MN   TRAINED SPOTTER

            LARGE PINE TREES DOWN.

0415 PM     TSTM WND DMG     MORA                    45.88N 93.29W
09/20/2007                   KANABEC            MN   TRAINED SPOTTER

            HIGH WINDS. MANY TREES DOWN IN CITY. 18 INCHS IN
            DIAMETER. MINOR STRUCTURAL DAMAGE TO SOME HOMES.

0418 PM     TSTM WND DMG     LITCHFIELD              45.12N 94.53W
09/20/2007                   MEEKER             MN   AMATEUR RADIO

            TREES SHREADED.

0423 PM     TSTM WND DMG     LITCHFIELD              45.12N 94.53W
09/20/2007                   MEEKER             MN   AMATEUR RADIO

            22 INCH DIAMETER TREES DOWN.

0425 PM     HAIL             LITCHFIELD              45.12N 94.53W
09/20/2007  E0.88 INCH       MEEKER             MN   TRAINED SPOTTER

0430 PM     TSTM WND DMG     LITCHFIELD              45.12N 94.53W
09/20/2007                   MEEKER             MN   AMATEUR RADIO

            TREE DOWN ON MOBILE HOME NORTH SIDE OF LITCHFIELD.

0433 PM     HAIL             LITCHFIELD              45.12N 94.53W
09/20/2007  E1.75 INCH       MEEKER             MN   AMATEUR RADIO

0454 PM     HAIL             COKATO                  45.08N 94.19W
09/20/2007  E0.75 INCH       WRIGHT             MN   AMATEUR RADIO

0505 PM     HAIL             WAVERLY                 45.07N 93.97W
09/20/2007  E1.75 INCH       WRIGHT             MN   TRAINED SPOTTER

0505 PM     HAIL             MONTROSE                45.07N 93.91W
09/20/2007  E0.75 INCH       WRIGHT             MN   TRAINED SPOTTER

0508 PM     FLASH FLOOD      BLOOMINGTON             44.83N 93.32W
09/20/2007                   HENNEPIN           MN   TRAINED SPOTTER

            6 TO 12 INCHES OF WATER ACROSS ROADWAY...83 ST SOUTH AND
            PENN AVE.

0510 PM     HAIL             2 N MONTROSE            45.10N 93.91W
09/20/2007  E1.75 INCH       WRIGHT             MN   TRAINED SPOTTER

0512 PM     HAIL             2 SW BUFFALO            45.16N 93.90W
09/20/2007  E1.00 INCH       WRIGHT             MN   TRAINED SPOTTER

0515 PM     HAIL             BUFFALO                 45.18N 93.87W
09/20/2007  E1.00 INCH       WRIGHT             MN   TRAINED SPOTTER

0517 PM     HAIL             DELANO                  45.04N 93.79W
09/20/2007  E0.88 INCH       WRIGHT             MN   TRAINED SPOTTER

0520 PM     HAIL             WATERTOWN               44.96N 93.85W
09/20/2007  E1.75 INCH       CARVER             MN   PUBLIC

0520 PM     HAIL             PLYMOUTH                45.02N 93.46W
09/20/2007  E0.88 INCH       HENNEPIN           MN   TRAINED SPOTTER

0522 PM     HAIL             MAPLE PLAIN             45.01N 93.66W
09/20/2007  E0.88 INCH       HENNEPIN           MN   AMATEUR RADIO

0523 PM     HAIL             BUFFALO                 45.18N 93.87W
09/20/2007  E1.00 INCH       WRIGHT             MN   TRAINED SPOTTER

0527 PM     HAIL             HANOVER                 45.16N 93.66W
09/20/2007  E0.75 INCH       HENNEPIN           MN   TRAINED SPOTTER

0527 PM     HAIL             LORETTO                 45.06N 93.64W
09/20/2007  E0.75 INCH       HENNEPIN           MN   TRAINED SPOTTER

0534 PM     TSTM WND DMG     WATERTOWN               44.96N 93.85W
09/20/2007                   CARVER             MN   AMATEUR RADIO

            TREES DOWN...JUST NORTH OF TOWN. 4-6 INCH BRANCHES DOWN
            IN TOWN.

0538 PM     HAIL             PLYMOUTH                45.02N 93.46W
09/20/2007  E0.88 INCH       HENNEPIN           MN   TRAINED SPOTTER

0550 PM     HAIL             GOLDEN VALLEY           44.99N 93.36W
09/20/2007  E1.00 INCH       HENNEPIN           MN   NWS EMPLOYEE

0550 PM     HAIL             NEW HOPE                45.04N 93.39W
09/20/2007  E0.75 INCH       HENNEPIN           MN   CO-OP OBSERVER

0550 PM     TSTM WND DMG     GOLDEN VALLEY           44.99N 93.36W
09/20/2007                   HENNEPIN           MN   NWS EMPLOYEE

            TREES DOWN...POWER OUT.

0602 PM     FUNNEL CLOUD     NEWPORT                 44.87N 93.00W
09/20/2007                   WASHINGTON         MN   LAW ENFORCEMENT

            NEAR WAKOTA BRIDGE.

0602 PM     HAIL             NEW BRIGHTON            45.07N 93.20W
09/20/2007  E0.75 INCH       RAMSEY             MN   TRAINED SPOTTER

0614 PM     FUNNEL CLOUD     INVER GROVE HEIGHTS     44.83N 93.06W
09/20/2007                   DAKOTA             MN   TRAINED SPOTTER

            AT SOUTHVIEW BLVD AND HWY 52.

0614 PM     HAIL             MINNEAPOLIS             44.96N 93.27W
09/20/2007  E0.88 INCH       HENNEPIN           MN   TRAINED SPOTTER

            I-35W AND 35TH STREET SOUTH.

0618 PM     FUNNEL CLOUD     EAGAN                   44.82N 93.16W
09/20/2007                   DAKOTA             MN   LAW ENFORCEMENT

            NEAR I-35E AND YANKEE DOODLE RD.

0620 PM     HAIL             2 S ST MICHAEL          45.18N 93.66W
09/20/2007  E0.75 INCH       WRIGHT             MN   AMATEUR RADIO

0620 PM     HAIL             BROOKLYN PARK           45.11N 93.35W
09/20/2007  E0.75 INCH       HENNEPIN           MN   TRAINED SPOTTER

0625 PM     HAIL             ROGERS                  45.19N 93.55W
09/20/2007  E1.00 INCH       HENNEPIN           MN   PUBLIC

            DIME TO QUARTER SIZE HAIL FELL FOR 5 MINUTES.

0625 PM     HAIL             BLAINE                  45.17N 93.21W
09/20/2007  E0.75 INCH       ANOKA              MN   TRAINED SPOTTER

0625 PM     FUNNEL CLOUD     INVER GROVE HEIGHTS     44.83N 93.06W
09/20/2007                   DAKOTA             MN   AMATEUR RADIO

            AT HWYS 13 AND 52

0626 PM     HAIL             ROGERS                  45.19N 93.55W
09/20/2007  E0.88 INCH       HENNEPIN           MN   AMATEUR RADIO

            INTERSECTION 494 AND 101.

0628 PM     HAIL             2 NW ROGERS             45.21N 93.58W
09/20/2007  E0.88 INCH       HENNEPIN           MN   TRAINED SPOTTER

            ALONG I94.

0630 PM     TORNADO          WOODBURY                44.91N 92.92W
09/20/2007                   WASHINGTON         MN   NWS STORM SURVEY

            IT HAS BEEN DETERMINED BY THE NWS STORM SURVEY...THAT AN
            EF ZERO TORNADO OCCURRED AT APPROXIMATELY 630 PM...IN THE
            SOUTHWEST CORNER OF THE CITY OF WOODBURY MINNESOTA ALONG
            BAILEY ROAD...THURSDAY EVENING.

0632 PM     FLASH FLOOD      ST PAUL                 44.95N 93.10W
09/20/2007                   RAMSEY             MN   TRAINED SPOTTER

            6 TO 12 INCHES WATER ON UNIVERSITY AVE BETWEEN SNELLING
            AND RICE.

0634 PM     FUNNEL CLOUD     HASTINGS                44.73N 92.85W
09/20/2007                   DAKOTA             MN   AMATEUR RADIO

            AT INTERSECTION OF 61 AND 10.

0635 PM     TSTM WND DMG     WOODBURY                44.91N 92.92W
09/20/2007                   WASHINGTON         MN   AMATEUR RADIO

            LATE REPORT RECEIVED AT 715 PM. 25 FOOT SPRUCE TREE DOWN.
            10 INCH LIMBS DOWN. STREET SIGNS DOWN.

0637 PM     FLASH FLOOD      MINNEAPOLIS             44.96N 93.27W
09/20/2007                   HENNEPIN           MN   TRAINED SPOTTER

            STORM SEWER GEYSER AT E RIVER RD AND PILLSBURY RD 10 TO
            25 FEET.

0637 PM     FLASH FLOOD      RICHFIELD               44.88N 93.28W
09/20/2007                   HENNEPIN           MN   TRAINED SPOTTER

            66TH AND PORTLAND S...2 FEET OF STANDING WATER AT
            INTERSECTION...2 STALLED CARS.

0640 PM     HAIL             ANOKA                   45.21N 93.39W
09/20/2007  E1.00 INCH       ANOKA              MN   TRAINED SPOTTER

0642 PM     HAIL             ST PAUL                 44.95N 93.10W
09/20/2007  E0.75 INCH       RAMSEY             MN   AMATEUR RADIO

0645 PM     HAIL             BECKER                  45.37N 93.87W
09/20/2007  E1.00 INCH       SHERBURNE          MN   TRAINED SPOTTER

0648 PM     FUNNEL CLOUD     RIVER FALLS             44.86N 92.62W
09/20/2007                   PIERCE             WI   LAW ENFORCEMENT

0700 PM     HAIL             COON RAPIDS             45.17N 93.31W
09/20/2007  E0.88 INCH       ANOKA              MN   TRAINED SPOTTER

            HWY 10 AND MAIN STREET

0703 PM     HAIL             COON RAPIDS             45.17N 93.31W
09/20/2007  E1.00 INCH       ANOKA              MN   TRAINED SPOTTER

0711 PM     HAIL             BLAINE                  45.17N 93.21W
09/20/2007  E1.00 INCH       ANOKA              MN   AMATEUR RADIO

0717 PM     FUNNEL CLOUD     3 NW ELLSWORTH          44.77N 92.52W
09/20/2007                   PIERCE             WI   TRAINED SPOTTER

0725 PM     HAIL             2 W COKATO              45.08N 94.23W
09/20/2007  E0.75 INCH       WRIGHT             MN   TRAINED SPOTTER

0928 PM     TSTM WND DMG     WOODVILLE               44.95N 92.29W
09/20/2007                   ST. CROIX          WI   TRAINED SPOTTER

            8 INCH TREE DOWNED.

0200 AM     HAIL             HEWITT                  46.32N 95.09W
09/21/2007  E1.00 INCH       TODD               MN   LAW ENFORCEMENT

            NICKEL TO QUARTER SIZE HAIL REPORTED.

National Weather Service Weather Forecast Office