Alert archive / Iowa / Flash Flood Warnings in 2017

Flash Flood Warning 2, NWS Quad Cities, IA

April 15, 2017Linn County, Iowa

NWS Quad Cities, IA issued this flash flood warning at Apr 15, 2017, 10:31 PM CDT for Linn County, Iowa. It was in force for 3 hr. 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
Apr 15, 2017, 10:31 PM CDT (03:31 UTC)
Expired
Apr 16, 2017, 1:30 AM CDT
In force
3 hr
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Flood severity
None

County Linn County, IA

The radar

The Quad Cities radar (KDVN), 98 km from the middle of the area, began a volume at 03:31 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

TimeReportWhereRemark
Apr 15, 10:33 PM CDTFLASH FLOODNw Cedar Rapids, IASEVERAL STALLED VEHICLES ON AREA STREETS IN THE CITY WITH WATER OVER STREET UNABLE TO DRAIN PROPERLY DUE TO INTENSE DOWNPOURS.
Apr 16, 1:36 AM CDTHEAVY RAIN 3.45Nnw Springville, IARAINFALL SINCE 4 PM. RAIN HAS ENDED.

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

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 3.5 hours before the alert went out and 104 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-pSkew-T log-p diagram, Davenport, at 00:00Z on 2017-04-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 183 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2017-04-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
183 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1821 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
133 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

564 
WGUS53 KDVN 160331
FFWDVN
IAC113-160630-
/O.NEW.KDVN.FF.W.0002.170416T0331Z-170416T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Quad Cities IA/IL
1031 PM CDT SAT APR 15 2017

The National Weather Service in the Quad Cities has issued a

* Flash Flood Warning for...
  Southern Linn County in east central Iowa...

* Until 130 AM CDT

* At 1030 PM CDT, the public reported street flooding in Cedar 
  Rapids. Up to two inches of rain have already fallen. 

Additional rainfall amounts of around an inch are possible in the 
warned area.

This includes Interstate 380 between mile markers 12 and 30.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

Do not drive into areas where water covers the road.

&&

LAT...LON 4212 9182 4211 9136 4186 9137 4186 9182

$$

DMD
2 follow-up statements
964 
WGUS73 KDVN 160434
FFSDVN

Flash Flood Statement
National Weather Service Quad Cities IA/IL
1134 PM CDT SAT APR 15 2017

IAC113-160630-
/O.CON.KDVN.FF.W.0002.000000T0000Z-170416T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Linn IA-
1134 PM CDT SAT APR 15 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 AM CDT FOR
SOUTHERN LINN COUNTY...

At 1124 PM CDT, Doppler radar indicates up to 3 inches of rain 
has fallen from north of Fairfax through Cedar Rapids to
near Springville with flash flooding likely occurring. Doppler
radar shows the rain has diminished to mainly light to pockets of
moderate intensity. However, additional showers and thunderstorms
have recently formed over southern Benton County and will likely
move back across the warned area over the next 1 to 2 hours 
bringing additional heavy rain and further increasing the threat
for flash flooding. 

Additional rainfall amounts of around an inch are possible in
the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 4212 9182 4211 9136 4186 9137 4186 9182

$$

MCCLURE
354 
WGUS73 KDVN 160628
FFSDVN

Flash Flood Statement
National Weather Service Quad Cities IA/IL
128 AM CDT SUN APR 16 2017

IAC113-160638-
/O.EXP.KDVN.FF.W.0002.000000T0000Z-170416T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Linn IA-
128 AM CDT SUN APR 16 2017

...THE FLASH FLOOD WARNING FOR SOUTHERN LINN COUNTY WILL EXPIRE AT
130 AM CDT...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 4212 9182 4211 9136 4186 9137 4186 9182

$$

MCCLURE

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 15, 7:03 PM CDTSevere Thunderstorm WarningDVNClinton, Scott43 min
Apr 15, 7:14 PM CDTSevere Thunderstorm WarningDVNBenton, Buchanan61 min
Apr 15, 7:56 PM CDTTornado WarningDVNBenton, Buchanan, Delaware, Linn49 min
Apr 15, 8:00 PM CDTSevere Thunderstorm WarningDVNBenton, Linn60 min
Apr 15, 8:49 PM CDTRiver Flood WatchDVNIowa, Johnson6 days
Apr 15, 8:58 PM CDTSevere Thunderstorm WarningDVNClinton, Jackson, Jones43 min
Apr 15, 11:01 PM CDTFlash Flood WarningDVNJones3 hr
Apr 15, 11:53 PM CDTSpecial Weather StatementDVNClinton, Scott112 min
Apr 16, 8:03 AM CDTRiver Flood WarningDVNClinton, Scott5 days
Apr 16, 9:59 AM CDTRiver Flood WatchDVNLouisa5 days
Apr 16, 9:59 AM CDTRiver Flood WatchDVNCedar, Louisa, Muscatine4 days
Apr 16, 10:01 AM CDTRiver Flood WarningDVNIowa7 days

Nearby

Flash Flood Warnings in Iowa, 2017Every flash flood warning 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.