Alert archive / South Carolina / Flash Flood Watches in 2011

Flash Flood Watch 1, NWS Columbia, SC

March 30, 2011Lexington County, South Carolina

NWS Columbia, SC issued this flash flood watch at Mar 30, 2011, 3:55 PM EDT for Lexington County, South Carolina. It took effect at Mar 30, 2011, 4:00 PM EDT. It was in force for 41 hr.

The area

The counties it named.

The facts

Issued
Mar 30, 2011, 3:55 PM EDT (19:55 UTC)
In effect from
Mar 30, 2011, 4:00 PM EDT
Expired
Apr 1, 2011, 9:05 AM EDT
In force
41 hr
Issued by
NWS Columbia, SC
Flood severity
None

County Lexington County, SC

The radar

The Columbia radar (KCAE), 15 km from the middle of the area, began a volume at 19:53 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

Charleston AFB, SC (KCHS), launched 12:00Z, 7.9 hours before the alert went out and 162 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-pSkew-T log-p diagram, Charleston AFB, SC at 12:00Z on 2011-03-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 145 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Charleston AFB, SC at 12:00Z on 2011-03-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 334 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
145 J/kg
Mixed-layer CIN
-103 J/kg
Mixed-layer LCL
529 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
334 m²/s²
0-3 km storm-relative helicity
407 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.3

Open this sounding in Storm Lab

Nearby

Flash Flood Watches in South Carolina, 2011Every flash flood watch in 2011

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.