Alert archive / Iowa / Tornado Warnings in 2011

Tornado Warning 10, NWS Quad Cities, IA

May 25, 2011Des Moines County, Louisa County, Iowa; Mercer County, Illinois

NWS Quad Cities, IA issued this tornado warning at May 25, 2011, 5:11 PM CDT for Des Moines County, Louisa County, Iowa; Mercer County, Illinois. It was in force for 23 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: May 25, 2011, 5:11 PM CDT (22:11 UTC)
Expired: May 25, 2011, 5:34 PM CDT
In force: 23 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon

Counties Des Moines County, IA, Louisa County, IA, Mercer County, IL

The radar

The Quad Cities radar (KDVN), 79 km from the middle of the area, began a volume at 22:15 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 25, 2:31 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.2 hours before the alert went out and 229 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1832 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 561 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 253 m²/s²
0-3 km storm-relative helicity: 222 m²/s²
Significant tornado parameter: 1.6
Supercell composite: 10.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

220 
WFUS53 KDVN 252211
TORDVN
IAC057-115-ILC131-252245-
/O.NEW.KDVN.TO.W.0010.110525T2211Z-110525T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
511 PM CDT WED MAY 25 2011

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN MERCER COUNTY IN NORTHWEST ILLINOIS...
  DES MOINES COUNTY IN SOUTHEAST IOWA...
  SOUTHEASTERN LOUISA COUNTY IN SOUTHEAST IOWA...

* UNTIL 545 PM CDT.

* AT 510 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  TORNADO NEAR SPERRY...OR 10 MILES NORTH OF BURLINGTON...MOVING
  NORTH AT 35 MPH.

* THE TORNADO WILL BE NEAR...
  MEDIAPOLIS AND KINGSTON AROUND 515 PM CDT...
  KOSSUTH AND GARLAND AROUND 520 PM CDT...
  NORTHFIELD...NEWPORT AND MORNING SUN AROUND 525 PM CDT...
  ELRICK JUNCTION AND OAKVILLE AROUND 530 PM CDT...
  TOOLESBORO AROUND 535 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE IN A TORNADO IS IN A BASEMENT OR INTERIOR ROOM
OR HALLWAY ON THE LOWEST FLOOR OF A BUILDING.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT WEDNESDAY EVENING
FOR SOUTHEAST IOWA AND NORTHWESTERN ILLINOIS AND NORTHEAST MISSOURI.

&&

LAT...LON 4087 9133 4124 9130 4122 9075 4107 9091
      4107 9095 4101 9095 4087 9103 4083 9108
TIME...MOT...LOC 2211Z 192DEG 31KT 4096 9116

$$

12

2 follow-up statements

256 
WWUS53 KDVN 252218
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
518 PM CDT WED MAY 25 2011

IAC057-115-ILC131-252245-
/O.CON.KDVN.TO.W.0010.000000T0000Z-110525T2245Z/
LOUISA IA-DES MOINES IA-MERCER IL-
518 PM CDT WED MAY 25 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 545 PM CDT FOR
SOUTHWESTERN MERCER...NORTHERN DES MOINES AND SOUTHEASTERN LOUISA
COUNTIES...

AT 515 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO.  THIS TORNADO WAS LOCATED APPROXIMATELY NEAR
MEDIAPOLIS...OR 11 MILES WEST OF OQUAWKA...MOVING NORTH AT 35 MPH.

THE TORNADO WILL BE NEAR...
  NORTHFIELD...NEWPORT AND MORNING SUN AROUND 525 PM CDT...
  ELRICK JUNCTION AND OAKVILLE AROUND 530 PM CDT...
  TOOLESBORO AND WAPELLO AROUND 535 PM CDT...
  NEW BOSTON AROUND 540 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE IN A TORNADO IS IN A BASEMENT OR INTERIOR ROOM
OR HALLWAY ON THE LOWEST FLOOR OF A BUILDING.

THIS STORM HAS ALREADY PRODUCED A TORNADO AND REMAINS A THREAT.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT WEDNESDAY EVENING
FOR SOUTHEAST IOWA AND NORTHWESTERN ILLINOIS AND NORTHEAST MISSOURI.

&&

LAT...LON 4093 9101 4089 9106 4094 9131 4124 9130
      4122 9075 4107 9091 4107 9095 4101 9095
TIME...MOT...LOC 2218Z 192DEG 31KT 4101 9115

$$

12

298 
WWUS53 KDVN 252234
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
534 PM CDT WED MAY 25 2011

IAC057-115-ILC131-252243-
/O.CAN.KDVN.TO.W.0010.000000T0000Z-110525T2245Z/
LOUISA IA-DES MOINES IA-MERCER IL-
534 PM CDT WED MAY 25 2011

...THE TORNADO WARNING FOR SOUTHWESTERN MERCER...NORTHERN DES MOINES
AND SOUTHEASTERN LOUISA COUNTIES IS CANCELLED...

THE THUNDERSTORM THAT WAS CAPABLE OF PRODUCING A TORNADO HAS 
WEAKENED. THEREFORE THE TORNADO WARNING HAS BEEN CANCELLED.

HOWEVER...THIS STORM IS STILL CAPABLE OF PRODUCING DAMAGING WINDS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT WEDNESDAY EVENING
FOR SOUTHEAST IOWA AND NORTHWESTERN ILLINOIS AND NORTHEAST MISSOURI.

LAT...LON 4093 9101 4089 9106 4094 9131 4124 9130
      4122 9075 4107 9091 4107 9095 4101 9095
TIME...MOT...LOC 2233Z 192DEG 31KT 4114 9111

$$

12

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 25, 2:20 AM CDT	Special Weather Statement	DVN	Lee, Van Buren	70 min
May 25, 2:38 AM CDT	Flash Flood Watch	DVN	Des Moines, Henry, Jefferson, Keokuk, Lee, Louisa and 2 more	20 hr
May 25, 3:46 AM CDT	Special Weather Statement	DVN	Des Moines, Iowa, Johnson, Keokuk, Louisa, Muscatine and 1 more	59 min
May 25, 6:37 AM CDT	River Flood Warning	DVN	Iowa, Johnson	7 days
May 25, 6:37 AM CDT	River Flood Warning	DVN	Lee	52 hr
May 25, 9:27 AM CDT	River Flood Warning	DVN	Clinton, Scott	12 hr
May 25, 9:27 AM CDT	River Flood Warning	DVN	Keokuk	12 hr
May 25, 9:27 AM CDT	River Flood Warning	DVN	Des Moines, Henry, Lee	6 days
May 25, 11:46 AM CDT	River Flood Warning	DVN	Des Moines	13 days
May 25, 11:46 AM CDT	River Flood Warning	DVN	Des Moines, Lee	14 days
May 25, 11:46 AM CDT	River Flood Warning	DVN	Johnson, Washington	34 hr
May 25, 2:31 PM CDT	Wind Advisory	DVN	Benton, Buchanan, Cedar, Clinton, Delaware, Dubuque and 12 more	7 hr
May 25, 3:41 PM CDT	River Flood Warning	DVN	Lee, Van Buren	20 hr
May 25, 4:08 PM CDT	Severe Thunderstorm Warning	DVN	Van Buren	52 min
May 25, 4:35 PM CDT	Tornado Warning	DVN	Des Moines, Henry, Lee	40 min
May 25, 4:55 PM CDT	Flash Flood Warning	DVN	Des Moines, Henry, Jefferson, Lee, Van Buren	5 hr
May 25, 5:05 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Louisa	40 min
May 25, 5:34 PM CDT	Flash Flood Warning	DVN	Des Moines, Louisa	4 hr
May 25, 5:34 AM CDT	Special Weather Statement	DVN	Bureau, Putnam	56 min
May 25, 7:08 AM CDT	Special Weather Statement	DVN	Bureau, Putnam	52 min
May 25, 9:27 AM CDT	River Flood Warning	DVN	Hancock, McDonough	5 days
May 25, 11:46 AM CDT	River Flood Warning	DVN	Hancock	13 days
May 25, 5:30 PM CDT	Severe Thunderstorm Warning	DVN	Henderson, Henry, Mercer, Warren	45 min
May 25, 6:31 PM CDT	Severe Thunderstorm Warning	DVN	Bureau, Putnam	44 min

Nearby

Tornado Warnings in Iowa, 2011 Tornado Warnings in Illinois, 2011 Every tornado warning in 2011 Tornadoes in 2011

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.