Alert archive / Iowa / Flash Flood Warnings in 2013

Flash Flood Warning 9, NWS Sioux Falls, SD

May 27, 20136 counties in Iowa

NWS Sioux Falls, SD issued this flash flood warning at May 27, 2013, 10:34 AM CDT for 6 counties in Iowa. It was in force for 12 hr. 3 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
May 27, 2013, 10:34 AM CDT (15:34 UTC)
Expired
May 27, 2013, 10:30 PM CDT
In force
12 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Buena Vista County, IA, Cherokee County, IA, Clay County, IA, O'Brien County, IA, Plymouth County, IA, Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 83 km from the middle of the area, began a volume at 15:37 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
May 27, 10:45 AM CDTFLASH FLOOD2 W Newell, IAFLASH FLOOD WATER INTO FIELDS
May 27, 12:20 PM CDTHEAVY RAIN 2.13Rock Valley, IA5.23 INCHES OVER THE PAST TWO DAYS.
May 27, 9:00 PM CDTFLOOD1 E Merrill, IAHIGHWAY 75 NEAR MERRILL HAS WATER FROM FLOYD RIVER OVER THE NORTHBOUND LANE.

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

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 3.6 hours before the alert went out and 184 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, Omaha, NE at 12:00Z on 2013-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2013-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -92 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
900 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
-92 m²/s²
0-3 km storm-relative helicity
-371 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.

576 
WGUS53 KFSD 271534
FFWFSD
IAC021-035-041-141-149-167-280330-
/O.NEW.KFSD.FF.W.0009.130527T1534Z-130528T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1034 AM CDT MON MAY 27 2013

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  BUENA VISTA COUNTY IN NORTHWEST IOWA
  CHEROKEE COUNTY IN NORTHWEST IOWA
  CLAY COUNTY IN NORTHWEST IOWA
  O'BRIEN COUNTY IN NORTHWEST IOWA
  PLYMOUTH COUNTY IN NORTHWEST IOWA
  SIOUX COUNTY IN NORTHWEST IOWA

* UNTIL 1030 PM CDT MONDAY

* AT 1026 AM CDT...TRAINED WEATHER SPOTTERS REPORTED FLASH 
FLOODING   ACROSS THE WARNED AREA. VERY HEAVY RAINFALL OF FIVE TO 
TEN INCHES ACROSS THE AREA HAS CREATED FLOODING ACROSS NORTHWEST 
IOWA OVERNIGHT.  FLOOD WATERS CONTINUE TO COVER MANY AREA ROADWAYS. 
FLOOD WATERS SHOULD CONTINUE TO RECEED TODAY AS MAINLY DRY 
CONDITIONS ARE EXPECTED TONIGHT. THIS AREAL FLOOD WARNING REPLACES 
THE PREVIOUS WARNINGS IN EFFECT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

FLOODING IS OCCURRING OR IS IMMINENT. IT IS IMPORTANT TO KNOW WHERE
YOU ARE RELATIVE TO STREAMS...RIVERS...OR CREEKS WHICH CAN BECOME
KILLERS IN HEAVY RAINS. CAMPERS AND HIKERS SHOULD AVOID STREAMS OR
CREEKS.

&&

LAT...LON 4258 9642 4306 9647 4308 9645 4310 9646
      4312 9643 4315 9647 4326 9649 4318 9498
      4255 9492

$$

BT

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 26, 10:18 PM CDTFlash Flood WarningFSDBuena Vista, Cherokee, Clay, O'Brien6 hr
May 27, 12:42 AM CDTFlash Flood WarningFSDLyon, Plymouth, Sioux4 hr
May 27, 2:01 AM CDTRiver Flood WarningFSDCherokee3 days
May 27, 2:33 AM CDTRiver Flood WarningFSDPlymouth56 hr
May 27, 3:59 AM CDTRiver Flood WarningFSDLyon8 hr
May 27, 4:36 AM CDTAreal Flood WarningFSDBuena Vista, Cherokee, Clay, O'Brien9 hr
May 27, 4:46 AM CDTAreal Flood WarningFSDLyon, Sioux6 hr
May 27, 4:51 AM CDTAreal Flood WarningFSDLyon, Plymouth, Sioux6 hr
May 27, 6:57 AM CDTFlash Flood WatchFSDBuena Vista, Cherokee, Clay, Dickinson, Ida, Lyon and 5 more22 hr
May 27, 9:13 AM CDTRiver Flood WarningFSDPlymouth49 hr
May 27, 9:13 AM CDTRiver Flood WarningFSDWoodbury3 days
May 27, 10:19 AM CDTRiver Flood WarningFSDMonona, Woodbury11 hr
May 27, 10:40 AM CDTAreal Flood WarningFSDBuena Vista, Cherokee, Clay, O'Brien, Plymouth, Sioux24 hr

Nearby

Flash Flood Warnings in Iowa, 2013Every flash flood warning in 2013

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.