Alert archive / Kentucky / Flash Flood Watches in 2020

Flash Flood Watch 8, NWS Louisville, KY

July 30, 202049 counties in Kentucky; 10 counties in Indiana

NWS Louisville, KY issued this flash flood watch at Jul 30, 2020, 11:04 AM CDT for 49 counties in Kentucky; 10 counties in Indiana. It was in force for 40 hr.

The area

The counties it named.

The facts

Issued: Jul 30, 2020, 11:04 AM CDT (16:04 UTC)
Expired: Aug 1, 2020, 2:45 AM CDT
In force: 40 hr
Issued by: NWS Louisville, KY
Flood severity: None

All 59 counties

Clark County, IN, Crawford County, IN, Dubois County, IN, Floyd County, IN, Harrison County, IN, Jefferson County, IN, Orange County, IN, Perry County, IN, Scott County, IN, Washington County, IN, Adair County, KY, Allen County, KY, Anderson County, KY, Barren County, KY, Bourbon County, KY, Boyle County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Casey County, KY, Clark County, KY, Clinton County, KY, Cumberland County, KY, Edmonson County, KY, Fayette County, KY, Franklin County, KY, Garrard County, KY, Grayson County, KY, Green County, KY, Hancock County, KY, Hardin County, KY, Harrison County, KY, Hart County, KY, Henry County, KY, Jefferson County, KY, Jessamine County, KY, Larue County, KY, Lincoln County, KY, Logan County, KY, Madison County, KY, Marion County, KY, Meade County, KY, Mercer County, KY, Metcalfe County, KY, Monroe County, KY, Nelson County, KY, Nicholas County, KY, Ohio County, KY, Oldham County, KY, Russell County, KY, Scott County, KY, Shelby County, KY, Simpson County, KY, Spencer County, KY, Taylor County, KY, Trimble County, KY, Warren County, KY, Washington County, KY, Woodford County, KY

The radar

The Louisville radar (KLVX), 43 km from the middle of the area, began a volume at 16:07 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, 4.1 hours before the alert went out and 239 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: 51 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 1257 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 65 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Louisville, KY wrote its last area forecast discussion before this flash flood watch went out at Jul 30, 5:48 AM CDT, 5 hours 16 minutes earlier.

Area forecast discussion, Jul 30, 5:48 AM CDT, 5 hours 16 minutes before

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Hazardous weather outlook, Jul 30, 3:26 AM CDT, 7 hours 38 minutes before

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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
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        Please try again in a few minutes.
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The office that day

Everything else NWS Louisville, KY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 30, 10:35 AM CDT	Areal Flood Advisory	LMK	Jefferson, Oldham	3 hr
Jul 30, 1:33 PM CDT	Special Weather Statement	LMK	Logan	27 min
Jul 30, 4:45 PM CDT	Special Weather Statement	LMK	Oldham	45 min
Jul 30, 4:57 PM CDT	Areal Flood Advisory	LMK	Oldham, Shelby, Trimble	2 hr
Jul 30, 5:20 PM CDT	Special Weather Statement	LMK	Oldham, Shelby	55 min
Jul 30, 12:09 PM CDT	Areal Flood Advisory	LMK	Clark, Floyd, Harrison	3 hr
Jul 30, 1:52 PM CDT	Areal Flood Advisory	LMK	Washington	3 hr

Nearby

Flash Flood Watches in Kentucky, 2020 Flash Flood Watches in Indiana, 2020 Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.