Alert archive / Tennessee / Flood Watches in 2009

Flood Watch 5, NWS Nashville, TN

July 30, 200939 counties in Tennessee

NWS Nashville, TN issued this flood watch at Jul 30, 2009, 2:48 PM CDT for 39 counties in Tennessee. It took effect at Jul 30, 2009, 10:00 PM CDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued: Jul 30, 2009, 2:48 PM CDT (19:48 UTC)
In effect from: Jul 30, 2009, 10:00 PM CDT
Expired: Jul 31, 2009, 3:26 AM CDT
In force: 5 hr
Issued by: NWS Nashville, TN
Flood severity: None

All 39 counties

Bedford County, TN, Benton County, TN, Cannon County, TN, Cheatham County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Dickson County, TN, Fentress County, TN, Giles County, TN, Grundy County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Jackson County, TN, Lawrence County, TN, Lewis County, TN, Macon County, TN, Marshall County, TN, Maury County, TN, Montgomery County, TN, Overton County, TN, Perry County, TN, Pickett County, TN, Putnam County, TN, Robertson County, TN, Rutherford County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, Wayne County, TN, White County, TN, Williamson County, TN, Wilson County, TN

The radar

The Nashville radar (KOHX), 29 km from the middle of the area, began a volume at 19:50 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, 7.8 hours before the alert went out and 18 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: 649 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 466 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 58 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Nashville, TN wrote its last area forecast discussion before this flood watch went out at Jul 30, 2:33 PM CDT, 15 minutes earlier.

Area forecast discussion, Jul 30, 2:33 PM CDT, 15 minutes before

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Hazardous weather outlook, Jul 30, 5:17 AM CDT, 9 hours 31 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 9:10 PM CDT	Flash Flood Warning	OHX	Perry	77 min

Nearby

Flood Watches in Tennessee, 2009 Every flood watch in 2009

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.