Alert archive / Iowa / Tornado Warnings in 2014

Tornado Warning 7, NWS Quad Cities, IA

April 27, 2014Linn County, Iowa

NWS Quad Cities, IA issued this tornado warning at Apr 27, 2014, 4:23 PM CDT for Linn County, Iowa. It was in force for 22 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: Apr 27, 2014, 4:23 PM CDT (21:23 UTC)
Expired: Apr 27, 2014, 4:45 PM CDT
In force: 22 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Linn County, IA

The radar

The Quad Cities radar (KDVN), 108 km from the middle of the area, began a volume at 21:23 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 nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.4 hours before the alert went out and 114 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1230 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 467 m²/s²
0-3 km storm-relative helicity: 555 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

882 
WFUS53 KDVN 272123
TORDVN
IAC113-272145-
/O.NEW.KDVN.TO.W.0007.140427T2123Z-140427T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
423 PM CDT SUN APR 27 2014

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN LINN COUNTY IN EAST CENTRAL IOWA...

* UNTIL 445 PM CDT

* AT 419 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR WALFORD...AND MOVING NORTH AT 40 MPH.

  HAZARD...TORNADO.

  SOURCE...RADAR INDICATED ROTATION.

  IMPACT...MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE TO
           ROOFS...WINDOWS AND VEHICLES WILL OCCUR. FLYING DEBRIS
           WILL BE DEADLY TO PEOPLE AND ANIMALS. TREE DAMAGE IS
           LIKELY.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF WESTERN LINN COUNTY.

OTHER LOCATIONS AFFECTED INCLUDE MORGAN CREEK PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4204 9183 4202 9167 4186 9174 4186 9183
      4199 9184
TIME...MOT...LOC 2122Z 196DEG 36KT 4191 9178

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

1 follow-up statement

596 
WWUS53 KDVN 272131
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
431 PM CDT SUN APR 27 2014

IAC113-272140-
/O.CAN.KDVN.TO.W.0007.000000T0000Z-140427T2145Z/
LINN IA-
431 PM CDT SUN APR 27 2014

...THE TORNADO WARNING FOR SOUTHWESTERN LINN COUNTY IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND IS NO LONGER A 
THREAT TO PRODUCE A TORNADO.

LAT...LON 4204 9183 4202 9167 4186 9174 4186 9183
      4199 9184
TIME...MOT...LOC 2130Z 196DEG 36KT 4199 9175

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 27, 2:47 PM CDT	Flood Watch	DVN	Benton, Buchanan, Cedar, Clinton, Delaware, Des Moines and 15 more	27 hr
Apr 27, 3:13 PM CDT	Special Weather Statement	DVN	Jefferson, Van Buren	47 min
Apr 27, 3:23 PM CDT	Severe Thunderstorm Warning	DVN	Iowa, Jefferson, Johnson, Keokuk, Van Buren, Washington	67 min
Apr 27, 3:53 PM CDT	Tornado Warning	DVN	Iowa, Keokuk, Washington	37 min
Apr 27, 4:13 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Des Moines, Henry, Johnson, Linn, Louisa and 2 more	47 min
Apr 27, 4:43 PM CDT	Tornado Warning Tornado observed	DVN	Cedar, Jones, Linn	32 min
Apr 27, 4:52 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Clinton, Jackson, Jones, Linn, Muscatine and 1 more	38 min
Apr 27, 4:57 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Lee, Louisa	63 min

Nearby

Tornado Warnings in Iowa, 2014 Every tornado warning in 2014 Tornadoes in 2014

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.