Alert archive / Ohio / Flash Flood Warnings in 2018

Flash Flood Warning 11, NWS Cleveland, OH

August 10, 2018Mahoning County, Ohio

NWS Cleveland, OH issued this flash flood warning at Aug 10, 2018, 5:31 PM EDT for Mahoning County, Ohio. It was in force for 4 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: Aug 10, 2018, 5:31 PM EDT (21:31 UTC)
Expired: Aug 10, 2018, 9:30 PM EDT
In force: 4 hr
Issued by: NWS Cleveland, OH
Area: Storm-based polygon
Flood severity: None

County Mahoning County, OH

The radar

The Pittsburgh radar (KPBZ), 61 km from the middle of the area, began a volume at 21:35 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

Time	Report	Where	Remark
Aug 10, 5:40 PM EDT	FLOOD	Boardman, OH	NUMEROUS ROADS FLOODED THROUGHOUT TOWN. BASEMENTS FLOODED WITH AT LEAST 2 BASEMENTS COLLAPSED.
Aug 10, 5:40 PM EDT	FLOOD	Struthers, OH	AT LEAST 12 ROADS WITH CONSIDERABLE FLOODING, WATER DEPTH GENERALLY KNEE HIGH.
Aug 10, 5:50 PM EDT	FLOOD	Boardman, OH	CREEK OUT OF BANKS WITH WATER OVER ROAD AND YARDS ALONG WEST BOULEVARD IN BOARDMAN.

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

The nearest sounding before it

Pittsburgh, PA (KAGC), launched 12:00Z, 9.5 hours before the alert went out and 78 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 517 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 724 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 8 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

239 
WGUS51 KCLE 102131
FFWCLE
OHC099-110130-
/O.NEW.KCLE.FF.W.0011.180810T2131Z-180811T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Cleveland OH
531 PM EDT FRI AUG 10 2018

The National Weather Service in Cleveland has issued a

* Flash Flood Warning for...
  Southeastern Mahoning County in northeastern Ohio...

* Until 930 PM EDT.

* At 531 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have
  already fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Boardman, Campbell, Austintown, Struthers, Poland, New Middletown 
  and Lowellville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 4090 8071 4107 8075 4110 8052 4090 8052

$$

Clark

1 follow-up statement

048 
WGUS71 KCLE 102240
FFSCLE

Flash Flood Statement
National Weather Service Cleveland OH
640 PM EDT FRI AUG 10 2018

OHC099-110130-
/O.CON.KCLE.FF.W.0011.000000T0000Z-180811T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mahoning OH-
640 PM EDT FRI AUG 10 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 930 PM EDT FOR
SOUTHEASTERN MAHONING COUNTY...

At 636 PM EDT, Doppler radar indicated rain continued to fall across 
the warned area. Three and a half inches of rain have already fallen 
from Boardman to Poland. Flash flooding is expected to continue. 

Some locations that will experience flooding include...
Boardman, Campbell, Struthers, Poland, New Middletown and 
Lowellville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 4095 8072 4107 8075 4110 8052 4090 8052
      4090 8066

$$

Clark

The office that day

Everything else NWS Cleveland, OH issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 10, 2:20 PM EDT	Special Weather Statement	CLE	Ashland, Richland	40 min
Aug 10, 3:04 PM EDT	Special Weather Statement	CLE	Ashland, Wayne	56 min
Aug 10, 3:28 PM EDT	Areal Flood Advisory	CLE	Ashland, Richland	3 hr
Aug 10, 3:31 PM EDT	Severe Thunderstorm Warning	CLE	Stark, Summit	44 min
Aug 10, 3:46 PM EDT	Special Weather Statement	CLE	Holmes	29 min
Aug 10, 5:02 PM EDT	Areal Flood Advisory	CLE	Mahoning, Stark	3 hr

Nearby

Flash Flood Warnings in Ohio, 2018 Every flash flood warning in 2018

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.