Alert archive / Iowa / Tornado Warnings in 1991
Tornado Warning 16, NWS Des Moines, IA
NWS Des Moines, IA issued this tornado warning at Apr 29, 1991, 2:31 PM CDT for Pocahontas County, Iowa. It was in force for 44 min. 4 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Apr 29, 1991, 2:31 PM CDT (19:31 UTC)
- Expired
- Apr 29, 1991, 3:15 PM CDT
- In force
- 44 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Pocahontas County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 29, 2:32 PM CDT | Hail 1.75 | Pocahontas, IA | |
| Apr 29, 2:50 PM CDT | Tornado F1 | Pocahontas, IA | |
| Apr 29, 2:55 PM CDT | Tornado F1 | Pocahontas, IA | |
| Apr 29, 2:55 PM CDT | Hail 2.75 | Pocahontas, IA |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Omaha, NE (KOVN), launched 12:00Z, 7.5 hours before the alert went out and 210 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
- 298 J/kg
- Mixed-layer CIN
- -51 J/kg
- Mixed-layer LCL
- 732 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- -139 m²/s²
- 0-3 km storm-relative helicity
- -100 m²/s²
- Significant tornado parameter
- -0.1
- Supercell composite
- -1.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDSM 291931 TORDSM IAC151-292015- BULLETIN - EBS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE DES MOINES IA 231 PM CDT MON APR 29 1991 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A TORNADO WARNING EFFECTIVE UNTIL 315 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN NORTHWEST IOWA ...NORTHWESTERN POCAHONTAS COUNTY AT 230 PM CDT RADAR CONTINUED TO INDICATE A POSSIBLE TORNADO OVER SOUTHEASTERN BUENA VISTA COUNTY SOME 45 MILES WEST OF FORT DODGE. STORM WAS MOVING NORTHEAST AT 40 MILES AN HOUR. SOME CITIES INLCUDED IN THE WARNING ARE VARINA...LAURENS...HAVELOCK...AND PLOVER. THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE PATH OF THIS TORNA4DO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR POSSIBLE. AVOID WINDOWS. ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET INTO A DITCH OR CULVERT.
What forecasters said that day
The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, Apr 29, 1:24 PM CDT, 1 hour 7 minutes before
IAZ010-291930- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 123 PM CDT MON APR 29 1991 ...STRONG THUNDERSTORMS MOVING THROUGH CENTRAL IOWA... AT 122 PM...VERY STRONG THUNDERSTORMS WERE MOVING THROUGH THE SOUTH SIDE OF DES MOINES. WINDS AT THE DES MOINES AIRPORT REACHED ALMOST 50 MILES AN HOUR...AND VERY HEAVY RAINS AND PEA SIZED HAIL WAS ALSO OCCURRING. THESE STORMS WILL CONTINUE MOVING NORTH THROUGH CENTRAL IOWA UNTI L 230 PM THIS AFTERNOON. PEOPLE IN NORTHERN POLK COUNTY...AS WELL AS THOSE IN THE SAYLORVILLE LAKE RECREATIONAL AREA SHOULD BE PREPARED FOR THE RAPID ONSET OF THIS STORM. TRUETT
Special weather statement, Apr 29, 1:48 PM CDT, 43 minutes before
IAZ010-291945- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 147 PM CDT MON APR 29 1991 ...STRONG THUNDERSTORMS CONTINUE OVER CENTRAL IOWA... AT 145 PM...A CLUSTER OF VERY INTENSE THUNDERSTORMS CONTINUED OVER CENTRAL IOWA. THE STORMS WERE ABOUT 10 TO 15 MILES NORTH OF DOWNTOWN DES MOINES...NEAR THE POLK-STORY COUNTY LINE. THESE STORMS WERE PRODUCING WINDS OF 50 TO 60 MILES AN HOUR... AS WELL AS EXTREMELY HEAVY RAINS AND SMALL HAIL. THE STORM WAS MOVING NORTH AT 40 MILES AN HOUR...AND WILL BE PASSING THROUGH STORY COUNTY BETWEEN 145 AND 230 PM THIS AFTERNOON. PEOPLE IN STORY COUNTY SHOULD BE ALERT FOR POSSIBLE SEVERE WEATHER DEVELOPMENT. TRUETT/GOODSON ?
Special weather statement, Apr 29, 2:09 PM CDT, 22 minutes before
IAZ010-292035- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 207 PM CDT MON APR 29 1991 AT 259 PM...VERY INTENSE THUNDERSTORMS WERE INDICATED IN NORTHWEST SAC COUNTY...50 MILES EAST OF SIOUX CITY...AND IN SOUTHWEST CRAWFORD COUNTY...OR 40 MILES NORTHEAST OF COUNCIL BLUFFS. TORNADOES...VERY LARGE AND DAMAGING HAIL...BRIEF VERY HEAVY RAIN...DAMAGING WIND AND DEADLY LIGHTNING CAN BE EXPECTED AS THEY MOVE INTO BUENA VISTA AND CRAWFORD COUNTIES. OTHER VERY STRONG STORMS WERE NORTH AND NORTHWEST OF DES MOINES...FROM NEAR JEFFERSON TO NEAR STORY CITY. PEA TO MARBLE SIZE HAIL...55 MILE AN HOUR WIND...VERY HEAVY RAIN AND DEADLY LIGHTNING CAN BE EXPECTED WITH THESE STORMS. OTHER SHOWERS AND THUNDERSTORMS WERE 20 MILES EAST OF DES MOINES...AND ALSO IN THE SOUTHWEST PART OF THE STATE EAST AND SOUTH OF COUNCIL BLUFFS. THE SHOWERS AND STORMS WERE MOVING NORTH AT 40 TO 45 MILES AN HOUR. HUTTON
Special weather statement, Apr 29, 2:18 PM CDT, 13 minutes before
IAZ002-003-006-007-292000- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR NORTHEAST IOWA NATIONAL WEATHER SERVICE WATERLOO IA 215 PM CDT MON APR 29 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 800 PM CDT FOR ALL OF NORTHEAST AND NORTH CENTRAL IOWA... AT 105 PM...A 20 MILE WIDE LINE OF SHOWERS AND THUNDERSTORMS...WITH BRIEF HEAVY RAINS...CONTINUED IN EXTREME NORTHEAST IOWA FROM THE MISSISSIPPI RIVER NEAR PRAIRIE DU CHIEN WISCONSIN TO NEAR DECORAH AND ALONG THE MINNESOTA BORDER NORTH OF CHARLES CITY. THESES SHOWERS AND THUNDERSTORMS WERE MOVING TO THE NORTHEAST AT 30 MILES AN HOUR. TEMPERATURES WERE IN THE MIDDLE TO UPPER 60S WITH SOUTH WINDS 15 TO 30 MPH. FOR THE REST OF THIS AFTERNOON SCATTERED THUNDERSTORMS CAN BE EXPECTED. THE THUNDERSTORMS MAY BECOME SEVERE WITH LARGE HAIL...DAMAGING WINDS... DANGEROUS LIGHTNING AND BRIEF HEAVY RAINS. TEMPERATURES WILL CLIMB TO AROUND 70 WHILE WINDS CONTINUE FROM THE SOUTH 15 TO 30 MPH.
Special weather statement, Apr 29, 2:18 PM CDT, 13 minutes before
IAZ010-292035- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE...CORRECTION...TIME NATIONAL WEATHER SERVICE DES MOINES IA 207 PM CDT MON APR 29 1991 AT 159 PM...VERY INTENSE THUNDERSTORMS WERE INDICATED IN NORTHWEST SAC COUNTY...50 MILES EAST OF SIOUX CITY...AND IN SOUTHWEST CRAWFORD COUNTY...OR 40 MILES NORTHEAST OF COUNCIL BLUFFS. TORNADOES...VERY LARGE AND DAMAGING HAIL...BRIEF VERY HEAVY RAIN...DAMAGING WIND AND DEADLY LIGHTNING CAN BE EXPECTED AS THEY MOVE INTO BUENA VISTA AND CRAWFORD COUNTIES. OTHER VERY STRONG STORMS WERE NORTH AND NORTHWEST OF DES MOINES...FROM NEAR JEFFERSON TO NEAR STORY CITY. PEA TO MARBLE SIZE HAIL...55 MILE AN HOUR WIND...VERY HEAVY RAIN AND DEADLY LIGHTNING CAN BE EXPECTED WITH THESE STORMS. OTHER SHOWERS AND THUNDERSTORMS WERE 20 MILES EAST OF DES MOINES...AND ALSO IN THE SOUTHWEST PART OF THE STATE EAST AND SOUTH OF COUNCIL BLUFFS. THE SHOWERS AND STORMS WERE MOVING NORTH AT 40 TO 45 MILES AN HOUR. HUTTON
Special weather statement, Apr 29, 2:20 PM CDT, 11 minutes before
IAZ002-003-006-007-292000- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR NORTHEAST IOWA... CORRECTED FOR TIME NATIONAL WEATHER SERVICE WATERLOO IA 215 PM CDT MON APR 29 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 800 PM CDT FOR ALL OF NORTHEAST AND NORTH CENTRAL IOWA... AT 210 PM...A 20 MILE WIDE LINE OF SHOWERS AND THUNDERSTORMS...WITH BRIEF HEAVY RAINS...CONTINUED IN EXTREME NORTHEAST IOWA FROM THE MISSISSIPPI RIVER NEAR PRAIRIE DU CHIEN WISCONSIN TO NEAR DECORAH AND ALONG THE MINNESOTA BORDER NORTH OF CHARLES CITY. THESES SHOWERS AND THUNDERSTORMS WERE MOVING TO THE NORTHEAST AT 30 MILES AN HOUR. TEMPERATURES WERE IN THE MIDDLE TO UPPER 60S WITH SOUTH WINDS 15 TO 30 MPH. FOR THE REST OF THIS AFTERNOON SCATTERED THUNDERSTORMS CAN BE EXPECTED. THE THUNDERSTORMS MAY BECOME SEVERE WITH LARGE HAIL...DAMAGING WINDS... DANGEROUS LIGHTNING AND BRIEF HEAVY RAINS. TEMPERATURES WILL CLIMB TO AROUND 70 WHILE WINDS CONTI NUE FROM THE SOUTH 15 TO 30 MPH.
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 28, 7:05 PM CDT | Severe Thunderstorm Warning | DMX | Decatur | 40 min |
| Apr 28, 8:09 PM CDT | Severe Thunderstorm Warning | DMX | Decatur, Wayne | 51 min |
| Apr 28, 9:33 PM CDT | Flash Flood Warning | DMX | Wayne | 117 min |
| Apr 29, 1:25 PM CDT | Tornado Warning | DMX | Crawford, Sac | 35 min |
| Apr 29, 1:52 PM CDT | Tornado Warning | DMX | Crawford | 53 min |
| Apr 29, 1:57 PM CDT | Tornado Warning | DMX | Buena Vista | 33 min |
| Apr 29, 2:19 PM CDT | Tornado Warning | DMX | Hamilton, Hardin | 36 min |
| Apr 29, 2:40 PM CDT | Severe Thunderstorm Warning | DMX | Sac | 50 min |
| Apr 29, 3:05 PM CDT | Tornado Warning | DMX | Palo Alto | 40 min |
| Apr 29, 3:20 PM CDT | Severe Thunderstorm Warning | DMX | Worth | 40 min |
| Apr 29, 3:20 PM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo | 26 min |
Nearby
Tornado Warnings in Iowa, 1991Every tornado warning in 1991Tornadoes in 1991
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.