Alert archive / Minnesota / Severe Thunderstorm Warnings in 2004
Severe Thunderstorm Warning 406, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 21, 2004, 12:39 AM CDT for Cottonwood County, Minnesota. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jul 21, 2004, 12:39 AM CDT (05:39 UTC)
- Expired
- Jul 21, 2004, 1:15 AM CDT
- In force
- 36 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Counties, with a storm outline in the text
County Cottonwood County, MN
The radar
The Sioux Falls radar (KFSD), 142 km from the middle of the area, began a volume at 05:39 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
Did it verify
Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 20, 9:00 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
The nearest sounding before it
Minneapolis, MN (KMPX), launched 00:00Z, 5.7 hours before the alert went out and 146 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1847 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 1144 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 66 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS53 KFSD 210539
SVRFSD
MNC033-210615-
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1239 AM CDT WED JUL 21 2004
THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
COTTONWOOD COUNTY IN SOUTHWEST MINNESOTA
* UNTIL 115 AM CDT
* AT 1234 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING NICKEL SIZE HAIL.
THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 8 MILES
NORTH OF JEFFERS TO 9 MILES SOUTHEAST OF JEFFERS...OR FROM 22 MILES
NORTH OF WINDOM TO 8 MILES NORTH OF WINDOM...MOVING EAST AT 25 MPH.
* SEVERE THUNDERSTORMS WILL BE NEAR...
RURAL COTTONWOOD COUNTY THROUGH 1250 AM CDT
THIS STORM WILL PRODUCE LARGE HAIL. GO INSIDE A STURDY BUILDING AND
STAY AWAY FROM WINDOWS.
LAT...LON 4419 9530 4398 9523 4397 9486 4411 9486
4410 9511 4419 9511
$$
BOUSTEADWhat forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sioux Falls, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 20, 4:10 PM CDT, 8 hours 29 minutes earlier.
Area forecast discussion, Jul 20, 4:10 PM CDT, 8 hours 29 minutes before
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 410 PM CDT TUE JUL 20 2004 .DISCUSSION... MAIN CONCERNS IN THE SHORT-TERM ARE CONVECTIVE CHANCES THROUGH THURSDAY. FOR TONIGHT...WARM FRONT SITUATED FROM NEAR MOBRIDGE TO ONEIL AT 20Z. THIS FRONT IS EXPECTED TO SLOWLY PROGRESS EAST REACHING THE JAMES RIVER VALLEY BY EARLY EVENING. CAP CURRENTLY IN PLACE BUT A WEAK WAVE MOVING ACROSS WRN SD AT THIS TIME SHOULD INITIATE SCATTERED CONVECTION BY EARLY EVENING. WHILE SPEEDS BELOW 6 KM REMAIN ARE 30 KTS OR LESS...THERE IS IMPRESSIVE DIRECTIONAL SHEAR WHICH RESULTS IN CUMULATIVE SHEAR OF GREATER THAN 60 KTS. THIS COMBINED WITH MLCAPES OVER 3000 CAPES WOULD MEAN POTENTIAL FOR SUPERCELLS IF CONVECTION CAN DEVELOP. MAIN CONCERN WITH RELATIVELY LOW WBZEROES AND HIGH CAPE IS FOR VERY LARGE HAIL BUT THE THETA-E DIFFERENCE ALSO SUGGESTS POSSIBILITY FOR DAMAGING WINDS. THE BEST CHANCE FOR DEVELOPMENT WOULD SEEM TO BETWEEN HON AND MHE THEN MOVEING ESE AS IT EXPANDS. ONLY STRONG INHIBITION AND WEAK SYNOPTIC SCALE FORCING ARE LIMITS TO CONVECTION DEVELOPING. ASSUMING STORMS DEVELOP THEY WOULD TURN ESE TOWARD FSD OR SUX DURING THE EVENING. WITH HIGH DEW POINTS AND SRLY FLOW TEMPS WILL REMAIN IN THE LOW 70S IN THE ERN CWA WITH 60S CONFINED TO THE WRN AND NWRN CWA. ON WED...SECONDARY FRONT WILL SINK TO THE MISSOURI RIVER. DRIER AIR WILL SINK INTO THE NRN CWA WITH NRLY FLOW. DEW POINTS IN THE WRN CWA WILL REMAIN AROUND 70 SO IT WILL BECOME FAIRLY UNSTABLE DURING THE AFTERNOON. THERE WILL ALSO BE A WEAK WAVE MOVING ACROSS THE AREA. SHEAR IS NOT VERY GOOD AND WRLY FLOW IS NOT FAVORABLE FOR STRONG CONVERGENCE. HOWEVER...WITH WEAK FORCING AND STRONG INSTABILITY HAVE CONTINUED A LOW CHANCE IN THE WRN CWA ON WED AFTERNOON AND EARLY EVENING. EXPECT FRONT WILL BE OUT OF THE CWA AFTER 01Z SO ENDED CHC AT THAT POINT. TEMPS SHOULD BE VERY WARM WITH WRLY FLOW THROUGH THE LOW LEVELS AND SLIGHTLY LOWER DEW POINT WILL BETTER ALLOW FOR BETTER MIXING. SO EXPECT TEMPS WILL BE AS WARM IN MOST AREAS...ESP ERN CWA...AS TODAY. ON WED NIGHT AND THURSDAY...ANOTHER WAVE MOVES AROUND THE SRN PLAINS RIDGE INTO NRN NEBRASKA...THE 850 MB FRONT WILL SET UP ALONG THE NEBRASKA AND SOUTH DAKOTA BORDER. WITH 300 MB JET JUST TO NORTH AND RRQ OF JET IN VICINTY EXPECT THAT TSRA WILL DEVELOP LATE IN THE NIGHT. WHILE THE BEST CHC APPEARS TO BE IN NEBRASKA ATTM...WILL INTRODUCE A CHANCE OF TSRA ALONG THE MO RIVER LATE WED NIGHT AND CONTINUE INTO THU. WITH AMPLE CLOUD COVER IN THE SRN CWA...TEMPS WILL STRUGGLE INTO THE MID TO UPPER 70S. COLD AIR ADVECTION WILL ALSO RESULT IN COOLER READING NORTH ALTHOUGH MORE SUN WILL ALLOW TEMPS TO RISE INTO THE UPPER 70S. THE PCPN CHANCES WILL END ON THU NIGHT WITH MUCH COOLER AIR COMING IN. 700 MB TEMPS WILL DROP TO AROUND ZERO AND RESIDUAL BL MOISTURE WILL ALLOW CU TO DEVELOP RAPIDLY ON FRI AND SAT BY LATE MORNING. THE INCREASED CLOUD COVER AND 850 MB TEMPS AROUND 10C WILL KEEP TEMPS IN THE 70S BOTH DAYS. IN THE EXTENDED...HAVE GONE WITH THE ECMWF WHICH IS A COMPROMISE BETWEEN COLDER AND SLOWER GFS AND FASTER AND WARMER CANADIAN. ECMWF HAS UPPER LOW OVER THE CWA ON SUNDAY WITH 700 MB TEMPS AROUND 0C. WITH WEAK FORCING...HAVE ADDED CHANCE OF SHOWERS ON SUNDAY. 850 MB TEMPS WILL STAY COOL SO MAX TEMPS WILL AGAIN BE IN THE 70S ACROSS THE CWA. SLOW WARM UP EXPECTED THROUGH TUESDAY AS HEIGHTS SLOWLY RISE AND TEMPS MODERATE. HOWEVER...TEMPS WILL REMAIN BELOW SEASONAL NORMALS THROUGH TUESDAY. && .FSD...WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && SCHUMACHER
Hazardous weather outlook, Jul 20, 11:39 AM CDT, 13 hours before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 1139 AM CDT TUE JUL 20 2004 SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098- IAZ001>003-012>014-020>022-031-032-NEZ013-014-211200- 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- 1139 AM CDT TUE JUL 20 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA... SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS... A WEAK SURFACE BOUNDARY FROM NORFOLK NEBRASKA TO WINNER WILL LIFT NORTHEAST THIS AFTERNOON...AND SHOULD SERVE AS A FOCUS FOR SCATTERED THUNDERSTORM DEVELOPMENT. THE MAIN THREATS FROM THE STRONGEST THUNDERSTORMS WILL BE VERY LARGE HAIL...POSSIBLY AS LARGE AS TENNIS BALLS...AND STRONG AND GUSTY WINDS TO 70 MPH. WHILE TORNADOES ARE UNLIKELY...STORMS THAT DEVELOP ON THE FRONT WILL NEED TO BE MONITORED. THE BETTER CHANCE FOR AN ISOLATED TORNADO SHOULD BE ALONG A LINE FROM NEAR HURON TO MITCHELL TO SIOUX CITY. EXCESSIVE TEMPERATURES... HEAT INDICES WILL REACH THE 100 TO 105 DEGREE RANGE THIS AFTERNOON... AND MAY BRIEFLY HIT 105 TO 107 ALONG THE MISSOURI RIVER BETWEEN YANKTON AND SIOUX CITY. HIGH TEMPERATURES WILL BE IN THE MID TO UPPER 90S WITH DEWPOINT TEMPERATURES IN THE MID 70S. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THERE IS A SLIGHT CHANCE OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ALONG THE MISSOURI RIVER. THESE STORMS ARE NOT EXPECTED TO BE SEVERE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL BE POSSIBLE AFTER 500 PM CDT. && FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT WWW.CRH.NOAA.GOV/FSD. THIS INCLUDES THE GRAPHICAL HAZARDOUS WEATHER OUTLOOK. 08
In the hours before
Local storm report, Jul 20, 8:28 PM CDT, 4 hours 11 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
828 PM CDT TUE JUL 20 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0745 PM HAIL 1 N CANOVA 43.88N 97.50W
07/20/2004 1.75 INCH MINER SD TRAINED SPOTTER
0755 PM HAIL CANOVA 43.88N 97.50W
07/20/2004 3.00 INCH MINER SD PUBLIC
0814 PM HAIL 10 W MADISON 44.01N 97.31W
07/20/2004 0.88 INCH LAKE SD EMERGENCY MNGR
0821 PM TSTM WND GST MADISON 44.01N 97.11W
07/20/2004 70 MPH LAKE SD TRAINED SPOTTER
&&
PSLocal storm report, Jul 20, 8:37 PM CDT, 4 hours 2 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
837 PM CDT TUE JUL 20 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0823 PM TSTM WND GST MADISON 44.01N 97.11W
07/20/2004 70 MPH LAKE SD EMERGENCY MNGR
POWER LINES DOWN
0823 PM HAIL MADISON 44.01N 97.11W
07/20/2004 0.88 INCH LAKE SD EMERGENCY MNGR
&&
PSLocal storm report, Jul 20, 8:46 PM CDT, 3 hours 53 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
846 PM CDT TUE JUL 20 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0844 PM HAIL 7 N COLMAN 44.09N 96.82W
07/20/2004 2.75 INCH MOODY SD TRAINED SPOTTER
BROKE WINDSHIELD OF CAR
&&
PSLocal storm report, Jul 20, 9:03 PM CDT, 3 hours 36 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
903 PM CDT TUE JUL 20 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0835 PM HAIL WENTWORTH 44.00N 96.96W
07/20/2004 0.75 INCH LAKE SD FIRE DEPT/RESCUE
&&
PSLocal storm report, Jul 20, 9:13 PM CDT, 3 hours 26 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
913 PM CDT TUE JUL 20 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0907 PM HAIL 2 N FLANDREAU 44.08N 96.60W
07/20/2004 0.75 INCH MOODY SD AMATEUR RADIO
&&
PSLocal storm report, Jul 20, 9:34 PM CDT, 3 hours 5 minutes before
PRELIMINARY LOCAL STORM REPORT ... SUMMARY
NATIONAL WEATHER SERVICE SIOUX FALLS SD
934 PM CDT TUE JUL 20 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0614 PM HAIL 9 S MOUNT VERNON 43.58N 98.26W
07/20/2004 1.00 INCH DAVISON SD PUBLIC
0631 PM HAIL 8 ENE CORSICA 43.47N 98.26W
07/20/2004 1.00 INCH DOUGLAS SD TRAINED SPOTTER
0636 PM HAIL 6 S MITCHELL 43.65N 98.03W
07/20/2004 1.00 INCH DAVISON SD AMATEUR RADIO
0639 PM HAIL 5 S MITCHELL 43.66N 98.03W
07/20/2004 1.75 INCH DAVISON SD TRAINED SPOTTER
0645 PM HAIL MITCHELL 43.73N 98.03W
07/20/2004 1.75 INCH DAVISON SD LAW ENFORCEMENT
AT INTERSTATE 90 INTERCHANGE JUST WEST OF CITY.
0647 PM HAIL MITCHELL 43.73N 98.03W
07/20/2004 1.00 INCH DAVISON SD AMATEUR RADIO
ON SOUTH SIDE OF TOWN
0655 PM HAIL 6 WSW FULTON 43.69N 97.93W
07/20/2004 1.75 INCH HANSON SD TRAINED SPOTTER
0655 PM HAIL 10 W DIMOCK 43.48N 98.19W
07/20/2004 1.50 INCH DOUGLAS SD TRAINED SPOTTER
0700 PM HAIL 7 NE CORSICA 43.50N 98.31W
07/20/2004 0.75 INCH DOUGLAS SD TRAINED SPOTTER
0700 PM HAIL 14 S MOUNT VERNON 43.51N 98.26W
07/20/2004 0.75 INCH DAVISON SD TRAINED SPOTTER
0708 PM HAIL FULTON 43.73N 97.82W
07/20/2004 1.00 INCH HANSON SD TRAINED SPOTTER
0710 PM HAIL FULTON 43.73N 97.82W
07/20/2004 1.00 INCH HANSON SD TRAINED SPOTTER
0719 PM HAIL 8 NNE MITCHELL 43.84N 97.97W
07/20/2004 0.75 INCH DAVISON SD TRAINED SPOTTER
0723 PM HAIL 3 WNW FULTON 43.74N 97.88W
07/20/2004 0.75 INCH HANSON SD TRAINED SPOTTER
0723 PM HAIL 10 W DIMOCK 43.48N 98.19W
07/20/2004 0.75 INCH DOUGLAS SD TRAINED SPOTTER
0730 PM TSTM WND GST 6 SW MITCHELL 43.67N 98.12W
07/20/2004 60 MPH DAVISON SD TRAINED SPOTTER
CORN FLATTENED BY WINDS
0730 PM HAIL 12 S MOUNT VERNON 43.54N 98.26W
07/20/2004 0.88 INCH DAVISON SD LAW ENFORCEMENT
0732 PM HAIL 15 N DELMONT 43.27N 98.16W
07/20/2004 0.75 INCH DOUGLAS SD TRAINED SPOTTER
0745 PM HAIL 1 N CANOVA 43.88N 97.50W
07/20/2004 1.75 INCH MINER SD TRAINED SPOTTER
0745 PM HAIL 7 N SPENCER 43.83N 97.59W
07/20/2004 1.00 INCH MCCOOK SD PUBLIC
0752 PM HAIL CANOVA 43.88N 97.50W
07/20/2004 1.00 INCH MINER SD TRAINED SPOTTER
0755 PM HAIL CANOVA 43.88N 97.50W
07/20/2004 3.00 INCH MINER SD PUBLIC
0755 PM HAIL CANOVA 43.88N 97.50W
07/20/2004 0.88 INCH MINER SD EMERGENCY MNGR
0814 PM HAIL 10 W MADISON 44.01N 97.31W
07/20/2004 0.88 INCH LAKE SD EMERGENCY MNGR
0821 PM TSTM WND GST MADISON 44.01N 97.11W
07/20/2004 70 MPH LAKE SD TRAINED SPOTTER
0823 PM HAIL MADISON 44.01N 97.11W
07/20/2004 0.88 INCH LAKE SD EMERGENCY MNGR
0823 PM TSTM WND GST MADISON 44.01N 97.11W
07/20/2004 70 MPH LAKE SD EMERGENCY MNGR
POWER LINES DOWN
0835 PM HAIL WENTWORTH 44.00N 96.96W
07/20/2004 0.75 INCH LAKE SD FIRE DEPT/RESCUE
0844 PM HAIL 7 N COLMAN 44.09N 96.82W
07/20/2004 2.75 INCH MOODY SD TRAINED SPOTTER
BROKE WINDSHIELD OF CAR
0907 PM HAIL 2 N FLANDREAU 44.08N 96.60W
07/20/2004 0.75 INCH MOODY SD AMATEUR RADIO
&&
PSNearby
Severe Thunderstorm Warnings in Minnesota, 2004Every severe thunderstorm warning in 2004
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.