Alert archive / Indiana / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Indianapolis, IN

April 24, 2021Johnson County, Marion County, Indiana

NWS Indianapolis, IN issued this flash flood warning at Apr 24, 2021, 12:38 PM EDT for Johnson County, Marion County, Indiana. It was in force for 2 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 24, 2021, 12:38 PM EDT (16:38 UTC)
Expired
Apr 24, 2021, 12:40 PM EDT
In force
2 min
Issued by
NWS Indianapolis, IN
Area
Storm-based polygon
Flood severity
None

Counties Johnson County, IN, Marion County, IN

The radar

The Indianapolis radar (KIND), 14 km from the middle of the area, began a volume at 16:42 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

Cncnati-Daytn, OH (KILN), launched 12:00Z, 4.6 hours before the alert went out and 206 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, Cncnati-Daytn, OH at 12:00Z on 2021-04-24Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cncnati-Daytn, OH at 12:00Z on 2021-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 square meters per square second.1939587897117136Sfc1 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
1416 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
80 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

045 
WGUS53 KIND 241638
FFWIND
INC081-097-242030-
/O.NEW.KIND.FF.W.0001.210424T1638Z-210424T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Indianapolis IN
1238 PM EDT Sat Apr 24 2021

The National Weather Service in Indianapolis has issued a

* Flash Flood Warning for...
  Northeastern Johnson County in central Indiana...
  Marion County in central Indiana...

* Until 430 PM EDT.

* At 1238 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 5 inches of rain 
  have fallen. The expected rainfall rate is 1 inch in 1 hour. 
  Additional rainfall amounts up to 1 inch are possible in the 
  warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Indianapolis, Carmel, Fishers, Greenwood, Lawrence, Beech Grove, 
  Speedway, Southport, New Whiteland, Cumberland, Whiteland, 
  Meridian Hills, Warren Park, Homecroft, Rocky Ripple, Williams 
  Creek, Wynnedale, Spring Hill, Crows Nest and North Crows Nest.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3991 8633 3993 8624 3993 8595 3953 8595
      3955 8615

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1 INCH IN 1 HOUR

$$

MK
1 follow-up statement
365 
WGUS73 KIND 241640
FFSIND

Flash Flood Statement
National Weather Service Indianapolis IN
1240 PM EDT Sat Apr 24 2021

INC081-097-241650-
/O.CAN.KIND.FF.W.0001.000000T0000Z-210424T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Johnson IN-Marion IN-
1240 PM EDT Sat Apr 24 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN JOHNSON AND 
MARION COUNTIES...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

LAT...LON 3991 8633 3993 8624 3993 8595 3953 8595
      3955 8615

$$

JP

Nearby

Flash Flood Warnings in Indiana, 2021Every flash flood warning in 2021

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.