Alert archive / Tennessee / Flash Flood Watches in 2020

Flash Flood Watch 8, NWS Memphis, TN

September 1, 202010 counties in Tennessee; 5 counties in Arkansas

NWS Memphis, TN issued this flash flood watch at Sep 1, 2020, 9:49 AM CDT for 10 counties in Tennessee; 5 counties in Arkansas. It was in force for 41 hr.

The area

The counties it named.

The facts

Issued: Sep 1, 2020, 9:49 AM CDT (14:49 UTC)
Expired: Sep 3, 2020, 2:57 AM CDT
In force: 41 hr
Issued by: NWS Memphis, TN
Flood severity: None

Counties Clay County, AR, Craighead County, AR, Greene County, AR, Mississippi County, AR, Poinsett County, AR, Benton County, TN, Carroll County, TN, Crockett County, TN, Dyer County, TN, Gibson County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Weakley County, TN

The radar

The Memphis radar (KNQA), 87 km from the middle of the area, began a volume at 14:52 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

Nashville Metro, TN (KBNA), launched 12:00Z, 2.8 hours before the alert went out and 256 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: 69 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 570 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 62 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 Memphis, TN wrote its last area forecast discussion before this flash flood watch went out at Sep 1, 9:21 AM CDT, 28 minutes earlier.

Area forecast discussion, Sep 1, 9:21 AM CDT, 28 minutes before

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Hazardous weather outlook, Sep 1, 8:59 AM CDT, 50 minutes before

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In the hours before

Local storm report, Sep 1, 8:48 AM CDT, 1 hour 1 minute before

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The office that day

Everything else NWS Memphis, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 31, 7:12 PM CDT	Special Weather Statement	MEG	Lee, Monroe	48 min
Aug 31, 7:25 PM CDT	Severe Thunderstorm Warning	MEG	Chickasaw, Itawamba, Lee, Monroe, Pontotoc	50 min
Aug 31, 8:14 PM CDT	Special Weather Statement	MEG	Monroe	46 min
Sep 1, 4:59 AM CDT	Dense Fog Advisory	MEG	Alcorn, Itawamba, Lee, Monroe, Prentiss, Tishomingo	4 hr
Sep 1, 2:11 PM CDT	Special Weather Statement	MEG	Tishomingo	34 min
Sep 1, 6:05 PM CDT	Severe Thunderstorm Warning	MEG	Coahoma, Tunica	40 min
Sep 1, 6:48 PM CDT	Special Weather Statement	MEG	Tate, Tunica	27 min
Sep 1, 11:06 AM CDT	Special Weather Statement	MEG	Dyer	24 min
Sep 1, 12:11 PM CDT	Areal Flood Advisory	MEG	Dyer, Gibson, Lake, Obion	2 hr
Sep 1, 12:21 PM CDT	Special Weather Statement	MEG	Gibson, Weakley	39 min
Sep 1, 12:58 PM CDT	Special Weather Statement	MEG	Henry, Weakley	47 min
Sep 1, 1:02 PM CDT	Areal Flood Advisory	MEG	Carroll, Gibson, Henry, Weakley	3 hr
Sep 1, 1:41 PM CDT	Special Weather Statement	MEG	Benton, Carroll, Henry	49 min
Sep 1, 2:20 PM CDT	Areal Flood Advisory	MEG	Benton, Carroll, Gibson, Henry	3 hr
Sep 1, 4:55 PM CDT	Flash Flood Warning	MEG	Benton, Decatur	2 hr
Sep 1, 5:18 PM CDT	Tornado Warning	MEG	Lake	27 min
Sep 1, 5:35 PM CDT	Tornado Warning	MEG	Lake, Obion	25 min
Sep 1, 5:55 PM CDT	Tornado Warning	MEG	Obion	24 min
Sep 1, 8:44 AM CDT	Flash Flood Warning	MEG	Craighead	3 hr
Sep 1, 9:34 AM CDT	Areal Flood Advisory	MEG	Craighead, Greene	3 hr
Sep 1, 5:14 PM CDT	Special Weather Statement	MEG	Craighead	31 min
Sep 1, 5:32 PM CDT	Severe Thunderstorm Warning	MEG	Cross, Poinsett	26 min
Sep 1, 5:46 PM CDT	Special Weather Statement	MEG	Phillips	44 min

Nearby

Flash Flood Watches in Tennessee, 2020 Flash Flood Watches in Arkansas, 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.