Alert archive / Iowa / Tornado Warnings in 2017

Tornado Warning 8, NWS Quad Cities, IA

March 6, 20174 counties in Iowa

NWS Quad Cities, IA issued this tornado warning at Mar 6, 2017, 8:46 PM CST for 4 counties in Iowa. It was in force for 22 min. 2 reports 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: Mar 6, 2017, 8:46 PM CST (02:46 UTC)
Expired: Mar 6, 2017, 9:08 PM CST
In force: 22 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Benton County, IA, Iowa County, IA, Johnson County, IA, Linn County, IA

The radar

The Quad Cities radar (KDVN), 106 km from the middle of the area, began a volume at 02:48 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
Mar 6, 8:59 PM CST	TSTM WND GST 50	Cedar Rapids Municipal, IA	ASOS MEASURED.
Mar 6, 9:00 PM CST	HAIL 0.75	2 Wsw Cedar Rapids, IA

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
Mar 6, 1:54 PM CST	Tornado Watch	SPC	8 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.8 hours before the alert went out and 112 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: 39 J/kg
Mixed-layer CIN: -343 J/kg
Mixed-layer LCL: 1016 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 407 m²/s²
0-3 km storm-relative helicity: 489 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

988 
WFUS53 KDVN 070246
TORDVN
IAC011-095-103-113-070330-
/O.NEW.KDVN.TO.W.0008.170307T0246Z-170307T0330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
846 PM CST MON MAR 6 2017

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Northwestern Johnson County in east central Iowa...
  Southeastern Benton County in east central Iowa...
  Southwestern Linn County in east central Iowa...
  Northeastern Iowa County in east central Iowa...

* Until 930 PM CST
    
* At 846 PM CST, a severe thunderstorm capable of producing a tornado
  was located near Amana, or 7 miles east of Marengo, moving
  northeast at 70 mph.

  HAZARD...Tornado. 

  SOURCE...Radar indicated rotation. 

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely. 

* This dangerous storm will be near...
  Walford around 850 PM CST. 
  Cedar Rapids, Fairfax, Atkins and Swisher around 855 PM CST. 

Other locations impacted by this tornadic thunderstorm include East
Amana, Middle Amana, South Amana, West Amana, High Amana, Cedar
Rapids Municipal Airport, Morgan Creek Park, Homestead and Watkins.

This includes Interstate 380 between mile markers 13 and 16.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4204 9181 4189 9161 4186 9168 4181 9174
      4177 9180 4175 9195 4184 9203
TIME...MOT...LOC 0246Z 229DEG 61KT 4183 9193 

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

$$

MCCLURE

2 follow-up statements

101 
WWUS53 KDVN 070256
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
856 PM CST MON MAR 6 2017

IAC011-095-070305-
/O.CAN.KDVN.TO.W.0008.000000T0000Z-170307T0330Z/
Benton IA-Iowa IA-
856 PM CST MON MAR 6 2017

...THE TORNADO WARNING FOR SOUTHEASTERN BENTON AND NORTHEASTERN IOWA
COUNTIES IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore the warning has been cancelled.

A tornado watch remains in effect until 1000 PM CST for east central
Iowa.

LAT...LON 4204 9181 4189 9161 4186 9168 4177 9180
      4177 9183 4201 9183
TIME...MOT...LOC 0255Z 234DEG 59KT 4191 9175 

$$

IAC103-113-070330-
/O.CON.KDVN.TO.W.0008.000000T0000Z-170307T0330Z/
Johnson IA-Linn IA-
856 PM CST MON MAR 6 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 930 PM CST FOR
NORTHWESTERN JOHNSON AND SOUTHWESTERN LINN COUNTIES...
    
At 855 PM CST, a severe thunderstorm capable of producing a tornado
was located over Fairfax, or near Cedar Rapids, moving northeast at
65 mph.

HAZARD...Tornado. 

SOURCE...Radar indicated rotation. 

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely. 

This dangerous storm will be near...
  Cedar Rapids around 900 PM CST. 

Other locations impacted by this tornadic thunderstorm include Cedar
Rapids Municipal Airport and Morgan Creek Park.

This includes Interstate 380 between mile markers 13 and 16.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4204 9181 4189 9161 4186 9168 4177 9180
      4177 9183 4201 9183
TIME...MOT...LOC 0255Z 234DEG 59KT 4191 9175 

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

$$

MCCLURE

511 
WWUS53 KDVN 070308
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
908 PM CST MON MAR 6 2017

IAC103-113-070317-
/O.CAN.KDVN.TO.W.0008.000000T0000Z-170307T0330Z/
Johnson IA-Linn IA-
908 PM CST MON MAR 6 2017

...THE TORNADO WARNING FOR NORTHWESTERN JOHNSON AND SOUTHWESTERN LINN
COUNTIES IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore the warning has been cancelled.

A tornado watch remains in effect until 1000 PM CST for east central
Iowa.

LAT...LON 4204 9181 4189 9161 4186 9168 4177 9180
      4177 9183 4201 9183
TIME...MOT...LOC 0305Z 229DEG 61KT 4205 9153 

$$

MCCLURE

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 6, 8:02 PM CST	Severe Thunderstorm Warning	DVN	Benton, Buchanan, Iowa	58 min
Mar 6, 8:04 PM CST	Severe Thunderstorm Warning	DVN	Keokuk	56 min
Mar 6, 8:29 PM CST	Severe Thunderstorm Warning	DVN	Delaware, Johnson, Linn	61 min
Mar 6, 8:40 PM CST	Tornado Warning	DVN	Buchanan, Delaware	38 min
Mar 6, 8:46 PM CST	Severe Thunderstorm Warning	DVN	Keokuk, Washington	74 min
Mar 6, 8:54 PM CST	Severe Thunderstorm Warning	DVN	Jefferson, Van Buren	81 min
Mar 6, 9:05 PM CST	Severe Thunderstorm Warning	DVN	Cedar, Jones	55 min
Mar 6, 9:07 PM CST	Tornado Warning	DVN	Jones, Linn	26 min
Mar 6, 9:19 PM CST	Severe Thunderstorm Warning	DVN	Dubuque	56 min
Mar 6, 9:28 PM CST	Severe Thunderstorm Warning	DVN	Johnson	47 min
Mar 6, 9:31 PM CST	Severe Thunderstorm Warning	DVN	Des Moines, Henry, Lee, Louisa, Muscatine	74 min
Mar 6, 9:31 PM CST	Tornado Warning	DVN	Dubuque, Jackson, Jones	44 min
Mar 6, 9:42 PM CST	Severe Thunderstorm Warning	DVN	Jackson	63 min
Mar 6, 9:49 PM CST	Severe Thunderstorm Warning	DVN	Clinton	71 min
Mar 6, 9:52 PM CST	Severe Thunderstorm Warning	DVN	Clinton, Scott	83 min
Mar 6, 9:55 PM CST	Tornado Warning	DVN	Jackson	38 min
Mar 6, 10:04 PM CST	Severe Thunderstorm Warning	DVN	Cedar	44 min
Mar 6, 10:10 PM CST	Tornado Warning	DVN	Muscatine, Scott	24 min
Mar 6, 10:17 PM CST	Tornado Warning	DVN	Cedar, Clinton, Scott	31 min
Mar 6, 10:23 PM CST	Tornado Warning	DVN	Clinton, Scott	26 min
Mar 6, 10:26 PM CST	Severe Thunderstorm Warning	DVN	Clinton, Scott	49 min
Mar 6, 10:46 PM CST	Tornado Warning	DVN	Clinton, Jackson	20 min
Mar 7, 3:32 AM CST	Red Flag Warning	DVN	Benton, Buchanan, Cedar, Clinton, Delaware, Des Moines and 15 more	14 hr
Mar 7, 3:37 AM CST	Wind Advisory	DVN	Benton, Buchanan, Delaware, Dubuque, Jackson, Jones and 1 more	12 hr

Nearby

Tornado Warnings in Iowa, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.