Alert archive / Louisiana / Flash Flood Watches in 2020
Flash Flood Watch 9, NWS Shreveport, LA
NWS Shreveport, LA issued this flash flood watch at Sep 23, 2020, 3:52 AM CDT for 10 parishes in Louisiana. It took effect at Sep 23, 2020, 4:00 AM CDT. It was in force for 17 hr.
The area
The counties it named.
The facts
- Issued
- Sep 23, 2020, 3:52 AM CDT (08:52 UTC)
- In effect from
- Sep 23, 2020, 4:00 AM CDT
- Expired
- Sep 23, 2020, 8:44 PM CDT
- In force
- 17 hr
- Issued by
- NWS Shreveport, LA
- Flood severity
- None
Counties Caldwell Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Sabine Parish, LA, Union Parish, LA, Winn Parish, LA
The radar
The Ft Polk radar (KPOE), 109 km from the middle of the area, began a volume at 08:55 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
Shreveport, LA (KSHV), launched 00:00Z, 8.9 hours before the alert went out and 118 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 522 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 173 m²/s²
- 0-3 km storm-relative helicity
- 130 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Shreveport, LA wrote its last area forecast discussion before this flash flood watch went out at Sep 23, 1:11 AM CDT, 2 hours 41 minutes earlier.
Area forecast discussion, Sep 23, 1:11 AM CDT, 2 hours 41 minutes before
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</html>Hazardous weather outlook, Sep 22, 6:00 AM CDT, 21 hours 52 minutes before
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</html>The office that day
Everything else NWS Shreveport, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 23, 9:34 AM CDT | River Flood Warning | SHV | Franklin, Morris, Red River, Titus | 44 hr |
| Sep 23, 7:33 AM CDT | Areal Flood Advisory | SHV | Bienville, Bossier, Caddo, De Soto, Red River, Webster | 3 hr |
| Sep 23, 10:48 AM CDT | Flash Flood Warning | SHV | Ouachita, Union | 4 hr |
| Sep 23, 11:09 AM CDT | Areal Flood Advisory | SHV | Ouachita | 4 hr |
Nearby
Flash Flood Watches in Louisiana, 2020Every 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.