Alert archive / Ohio / Flash Flood Warnings in 2020

Flash Flood Warning 20, NWS Cleveland, OH

September 7, 2020Marion County, Ohio

NWS Cleveland, OH issued this flash flood warning at Sep 7, 2020, 10:24 PM EDT for Marion County, Ohio. It was in force for 6 hr. 4 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: Sep 7, 2020, 10:24 PM EDT (02:24 UTC)
Expired: Sep 8, 2020, 4:19 AM EDT
In force: 6 hr
Issued by: NWS Cleveland, OH
Area: Storm-based polygon
Flood severity: None

County Marion County, OH

The radar

The Cincinnati radar (KILN), 136 km from the middle of the area, began a volume at 02:27 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
Sep 7, 10:46 PM EDT	HEAVY RAIN 3.52	2 Se Marion, OH	MESONET STATION EW8138 MARION.
Sep 7, 10:53 PM EDT	HEAVY RAIN 3.06	4 Ne Marion, OH	ASOS STATION KMNN MARION.
Sep 7, 10:54 PM EDT	HEAVY RAIN 4.46	3 E Marion, OH	MESONET STATION AV528 MARION.
Sep 8, 12:50 AM EDT	FLASH FLOOD	Marion, OH	CONSIDERABLE FLOODING ACROSS THE CITY WITH NUMEROUS WATER RESCUES FROM VEHICLES AND RESIDENCES.

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

The nearest sounding before it

Cncnati-Daytn, OH (KILN), launched 00:00Z, 2.4 hours before the alert went out and 134 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: 384 J/kg
Mixed-layer CIN: -147 J/kg
Mixed-layer LCL: 1381 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 135 m²/s²
0-3 km storm-relative helicity: 170 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.7

Open this sounding in Storm Lab

The text

As transmitted.

413 
WGUS51 KCLE 080224
FFWCLE
OHC101-080830-
/O.NEW.KCLE.FF.W.0020.200908T0224Z-200908T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Cleveland OH
1024 PM EDT Mon Sep 7 2020

The National Weather Service in Cleveland has issued a

* Flash Flood Warning for...
  Marion County in north central Ohio...

* Until 430 AM EDT Tuesday.

* At 1024 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Flash flooding is already occurring.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Marion, Prospect, La Rue, Waldo, Caledonia, New Bloomington and 
  Green Camp.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4066 8340 4064 8296 4049 8296 4049 8302
      4043 8303 4044 8325 4051 8325 4051 8342
      4065 8340

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 2 HOURS 

$$

Clark

2 follow-up statements

909 
WGUS71 KCLE 080520
FFSCLE

Flash Flood Statement
National Weather Service Cleveland OH
120 AM EDT Tue Sep 8 2020

OHC101-080830-
/O.CON.KCLE.FF.W.0020.000000T0000Z-200908T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Marion OH-
120 AM EDT Tue Sep 8 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 AM EDT EARLY THIS 
MORNING FOR MARION COUNTY...

At 120 AM EDT, local law enforcement reported widespread flooding 
with water resuces ongoing in Marion. Between 3 and 5 inches of rain 
have fallen. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  Marion, Prospect, La Rue, Waldo, Caledonia, New Bloomington and 
  Green Camp.

Rainfall rates have decreased but additional rainfall of a half inch 
to an inch is expected through 4 AM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4066 8340 4064 8296 4049 8296 4049 8302
      4043 8303 4044 8325 4051 8325 4051 8342
      4065 8340

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...0.5-1 INCH IN 2 HOURS 

$$

Clark

012 
WGUS71 KCLE 080819
FFSCLE

Flash Flood Statement
National Weather Service Cleveland OH
419 AM EDT Tue Sep 8 2020

OHC101-080829-
/O.CAN.KCLE.FF.W.0020.000000T0000Z-200908T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Marion OH-
419 AM EDT Tue Sep 8 2020

...FLASH FLOOD WARNING FOR MARION COUNTY HAS BEEN REPLACED WITH A 
FLOOD WARNING...

LAT...LON 4066 8340 4064 8296 4049 8296 4049 8302
      4043 8303 4044 8325 4051 8325 4051 8342
      4065 8340

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 9:48 PM EDT	Areal Flood Advisory	CLE	Marion, Morrow	6 hr
Sep 8, 2:30 AM EDT	River Flood Warning	CLE	Lorain	10 hr
Sep 8, 3:16 AM EDT	Special Weather Statement	CLE	Ashland, Erie, Huron, Lorain	89 min
Sep 8, 3:27 AM EDT	River Flood Warning	CLE	Trumbull	24 hr
Sep 8, 4:19 AM EDT	Areal Flood Warning	CLE	Marion, Morrow	6 hr
Sep 8, 3:48 PM EDT	Beach Hazards Statement	CLE	Ashtabula, Lake	6 hr
Sep 8, 3:52 PM EDT	Small Craft Advisory	CLE		6 hr
Sep 8, 5:45 PM EDT	Special Weather Statement	CLE	Lucas	30 min

Nearby

Flash Flood Warnings in Ohio, 2020 Every flash flood warning in 2020

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.