Alert archive / Iowa / Severe Thunderstorm Warnings in 2004
Severe Thunderstorm Warning 541, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Sep 15, 2004, 5:26 AM CDT for Buena Vista County, Iowa. It was in force for 34 min. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Sep 15, 2004, 5:26 AM CDT (10:26 UTC)
- Expired
- Sep 15, 2004, 6:00 AM CDT
- In force
- 34 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Counties, with a storm outline in the text
County Buena Vista County, IA
The radar
The Sioux Falls radar (KFSD), 153 km from the middle of the area, began a volume at 10:29 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 15, 5:45 AM CDT | TSTM WND DMG | 4 S Linn Grove, IA | TREES UPROOTED...CHICKEN PEN BLOWN OVER...TOP OF 100 FOOT SILO BLOWN OFF |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
Did it verify
Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 19 minutes after it went out.
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 nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 10.4 hours before the alert went out and 188 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
- 1520 J/kg
- Mixed-layer CIN
- -24 J/kg
- Mixed-layer LCL
- 1898 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 183 m²/s²
- 0-3 km storm-relative helicity
- 290 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 8.2
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS53 KFSD 151026 SVRFSD IAC021-151100- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 526 AM CDT WED SEP 15 2004 THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... BUENA VISTA COUNTY IN NORTHWEST IOWA * UNTIL 600 AM CDT * AT 526 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 15 MILES NORTHWEST OF ALTA TO 13 MILES SOUTHWEST OF ALTA... MOVING NORTHEAST AT 55 MPH. * SEVERE THUNDERSTORMS WILL BE NEAR... LAKESIDE...ALTA AROUND 535 AM CDT STORM LAKE...NEWELL AROUND 540 AM CDT TRUESDALE...LINN GROVE AROUND 545 AM CDT SIOUX RAPIDS AROUND 550 AM CDT MARATHON...ALBERT CITY AROUND 555 AM CDT THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH YOU SHOULD PREPARE FOR DAMAGING WINDS IN EXCESS OF 58 MPH...LARGE HAIL...HEAVY RAINS AND DEADLY LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER... PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS. LAT...LON 4292 9540 4256 9541 4256 9491 4291 9492 $$ RSR
What 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 Sep 15, 3:35 AM CDT, 1 hour 51 minutes earlier.
Area forecast discussion, Sep 15, 3:35 AM CDT, 1 hour 51 minutes before
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 335 AM CDT CDT WED SEP 15 2004 .DISCUSSION.. MAIN SHORT TERM FORECAST PROBLEMS ARE ONGOING WEATHER TODAY AND ITS IMPACTS ON TEMPERATURES AND FOG POTENTIAL TONIGHT. 07Z WATER VAPOR IMAGERY INDICATED STRONG SHORTWAVE TROUGH ENTERING WESTERN NEBRASKA WITH STRONG H300 DIFFLUENCE AHEAD OF FEATURE. WIDESPREAD PRECIP WAS SEEN ON MOSAICS BOTH ALONG THE COLD FRONT AND WARM FRONT. MODELS ALREADY BEGAN TO DIVERGE WITH HANDLING OF THIS FEATURE IN THE FIRST SIX HOURS OF THE FORECAST WITH GFS SEEMING TO BE A BIT CONVECTIVELY CONTAMINATED. EXPECT WAVE TO SLOW A BIT OVER THE NEXT FEW HOURS AS IT INTERACTS WITH FRONTAL ZONE AND CYCLOGENESIS INCREASES. THAT BEING SAID BEST SHOT OF PRECIP AFTER 12Z LOOKS TO BE IN THE NORTHEAST CWA...WITH PRECIP CHANCES DROPPING OF FAST TO THE SOUTH AFTER 13Z. ALTHOUGH THE RAIN WILL CONTINUE A BIT LONGER TODAY WONT CONTINUE FLOOD WATCH AS HEAVIEST RAINS HAVE ALREADY FALLEN...AND WILL JUST HAVE TO COVER THINGS WITH WARNINGS AS NEED BE. WAVE LOOKS TO CLEAR ENTIRE CWA AND STRONG SUBSIDENCE SETS IN. THIS SHOULD SCOUR OUT CLOUDS PRETTY QUICKLY SAVE FOR SOME WRAP AROUND STRATUS TO THE NORTHEAST. TEMPS SHOULD MIX OUT TO H850 PRETTY EASY IN THE SOUTH WITH LOTS OF SUNSHINE AND POST FRONTAL WIND...BUT WILL PROBABLY ONLY BE A FEW DEGREES WARMER THAN NOW IN THE NORTHEAST. TONIGHT SFC RIDGE SETTLES OVER AREA DROPPING OF WINDS. WITH ABUNDANT LOW LEVEL MOISTURE...INVERSION STRENGTHENING BY LL WARM ADVECTION AND WEAK BL WINDS...EXPECT TO SEE A GOOD RADIATIONAL FOG EVENT OVERNIGHT. DENSE FOG WILL ALSO BE POSSIBLE ACROSS THE SE AS WEAKEST WINDS WILL OCCUR AT TIME OF MAX RADIATIONAL COOLING. DESPITE GOOD COOLING...THINK MODELS ARE UNDER DOING SFC MOISTURE AND WILL GO NOT AS COLD AS GUIDANCE. AFTER THURSDAY MORNING WX SHOULD BE QUIET THROUGH SATURDAY. MODELS CONTINUE TO SHOW A SERIES OF SHORTWAVES SLIDING CROSS THE AREA THU-SAT. BUT SFC RIDGE TO THE SOUTH WILL SERIOUSLY IMPEDE ANY DECENT MOISTURE RETURN SO WILL CONTINUE DRY FORECAST. DID ADD SOME SMALL POPS ON SUNDAY AS STRONGER RETURN FLOW SETS UP...BUT MADE NO MAJOR CHANGES TO REST OF THE FORECAST. .FSD...WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. NE...NONE. IA...NONE. && JRM
Hazardous weather outlook, Sep 14, 11:47 AM CDT, 17 hours 39 minutes before
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. 08
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 14, 7:12 PM CDT | Flash Flood Warning | FSD | Buena Vista, Cherokee, Clay, Dickinson, O'Brien | 4 hr |
| Sep 15, 3:20 AM CDT | Flash Flood Warning | FSD | Lyon | 3 hr |
| Sep 15, 4:06 AM CDT | Flash Flood Warning | FSD | Clay, Dickinson, O'Brien, Osceola | 114 min |
| Sep 15, 7:01 AM CDT | Flash Flood Warning | FSD | Clay, Dickinson, O'Brien | 119 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.