Alert archive / Indiana / Flash Flood Warnings in 2017

Flash Flood Warning 8, NWS Northern Indiana

August 29, 2017Allen County, Indiana

NWS Northern Indiana issued this flash flood warning at Aug 29, 2017, 10:46 AM EDT for Allen County, Indiana. It was in force for 2 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
Aug 29, 2017, 10:46 AM EDT (14:46 UTC)
Expired
Aug 29, 2017, 1:15 PM EDT
In force
2 hr
Issued by
NWS Northern Indiana
Area
Storm-based polygon
Flood severity
None

County Allen County, IN

The radar

The Northern Indiana radar (KIWX), 64 km from the middle of the area, began a volume at 14:49 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
Aug 29, 11:11 AM EDTHEAVY RAIN 2.64Leo-Cedarville, INSTORM TOTAL RAINFALL SINCE 730 AM.
Aug 29, 12:20 PM EDTHEAVY RAIN 3.25Leo-Cedarville, INTOTAL AT THIS TIME.

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

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 2.8 hours before the alert went out and 209 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, Detroit, MI at 12:00Z on 2017-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 173 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, Detroit, MI at 12:00Z on 2017-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 square meters per square second.1939Sfc1 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
173 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
530 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

984 
WGUS53 KIWX 291446
FFWIWX
INC003-291715-
/O.NEW.KIWX.FF.W.0008.170829T1446Z-170829T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Northern Indiana
1046 AM EDT TUE AUG 29 2017

The National Weather Service in Northern Indiana  has issued a

* Flash Flood Warning for...
  Northeastern Allen County in northeastern Indiana...

* Until 115 PM EDT

* At 1042 AM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. 
  Rainfall amounts around three inches have already fallen. Flash 
  flooding is expected to begin shortly. 

* This includes the Leo-Cedarville and Grabill areas.

Additional rainfall amounts of one to two inches are expected in the 
warned area. 

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.

&&

LAT...LON 4127 8485 4117 8488 4116 8499 4119 8514
      4126 8506

$$

SKIP
1 follow-up statement
778 
WGUS73 KIWX 291617
FFSIWX

Flash Flood Statement
National Weather Service Northern Indiana
1217 PM EDT TUE AUG 29 2017

INC003-291715-
/O.CON.KIWX.FF.W.0008.000000T0000Z-170829T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allen IN-
1217 PM EDT TUE AUG 29 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 115 PM EDT FOR
NORTHEASTERN ALLEN COUNTY...

At 1214 PM EDT, Doppler radar and automated rain gauges indicated
thunderstorms had weakened over the area, but had produced 
widespread rainfall amounts between 3 and 5 inches. Flash flooding 
is underway. 

Additional rainfall amounts around an inch are possible in the 
warned area. The flood risk is expected to continue this afternoon. 
As the flash flood threat diminishes, an areal flood warning
will likely be issued.

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.

&&

LAT...LON 4127 8485 4117 8488 4116 8499 4119 8514
      4126 8506

$$

SKIP

The office that day

Everything else NWS Northern Indiana issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 29, 7:33 AM EDTDense Fog AdvisoryIWXLaGrange, Steuben2 hr
Aug 29, 8:04 AM EDTAreal Flood AdvisoryIWXAllen, Huntington, Wells, Whitley3 hr
Aug 29, 8:10 AM EDTFlash Flood WarningIWXAllen5 hr
Aug 29, 10:42 AM EDTRiver Flood WarningIWXAllen9 hr
Aug 29, 1:10 PM EDTAreal Flood WarningIWXAllen6 hr

Nearby

Flash Flood Warnings in Indiana, 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.