Alert archive / Iowa / Flash Flood Warnings in 2016

Flash Flood Warning 22, NWS Sioux Falls, SD

August 16, 2016Lyon County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Aug 16, 2016, 6:04 PM CDT for Lyon County, Iowa. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 16, 2016, 6:04 PM CDT (23:04 UTC)
Expired
Aug 16, 2016, 9:00 PM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

County Lyon County, IA

The radar

The Sioux Falls radar (KFSD), 33 km from the middle of the area, began a volume at 23:03 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

Omaha, NE (KOAX), launched 12:00Z, 11.1 hours before the alert went out and 228 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 2016-08-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 55 joules per kilogram.LCLLFCEL10008507005003002001001 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 2016-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 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
55 J/kg
Mixed-layer CIN
-140 J/kg
Mixed-layer LCL
1557 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
152 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

556 
WGUS53 KFSD 162304
FFWFSD
IAC119-170200-
/O.NEW.KFSD.FF.W.0022.160816T2304Z-160817T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
604 PM CDT TUE AUG 16 2016

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL LYON COUNTY IN NORTHWESTERN IOWA...

* UNTIL 900 PM CDT

* AT 603 PM CDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
  HEAVY RAIN ACROSS THE WARNED AREA. UP TO TWO INCHES OF RAIN HAVE
  ALREADY FALLEN IN 30 MINUTES. ANOTHER INCH OF RAIN WILL BE
  POSSIBLE IN THE NEXT HALF HOUR. AT THIS TIME IT IS EXPECTED THAT
  THE STORM WILL WEAKEN THROUGH THIS TIME. FLASH FLOODING IS
  EXPECTED TO BEGIN SHORTLY.

* FLASH FLOODING WILL REMAIN OVER MAINLY RURAL AREAS OF WEST CENTRAL
  LYON COUNTY.

LAT...LON 4333 9636 4336 9653 4337 9653 4344 9651
      4341 9634

$$

WEISSER
1 follow-up statement
390 
WGUS73 KFSD 170022
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
722 PM CDT TUE AUG 16 2016

IAC119-170031-
/O.CAN.KFSD.FF.W.0022.000000T0000Z-160817T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LYON IA-
722 PM CDT TUE AUG 16 2016

...THE FLASH FLOOD WARNING FOR WEST CENTRAL LYON COUNTY IS
CANCELLED...

THE HEAVY RAIN HAS ENDED. FLOOD WATERS HAVE RECEDED. FLOODING IS NO
LONGER EXPECTED TO POSE A THREAT. PLEASE CONTINUE TO HEED ANY
REMAINING ROAD CLOSURES.

LAT...LON 4333 9636 4336 9653 4337 9653 4344 9651
      4341 9634

$$

WEISSER

Nearby

Flash Flood Warnings in Iowa, 2016Every flash flood warning in 2016

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.