Alert archive / Georgia / Areal Flood Advisories in 2021

Areal Flood Advisory 21, NWS Tallahassee, FL

May 11, 2021Decatur County, Georgia

NWS Tallahassee, FL issued this areal flood advisory at May 11, 2021, 7:19 PM EDT for Decatur County, Georgia. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 11, 2021, 7:19 PM EDT (23:19 UTC)
Expired
May 11, 2021, 10:30 PM EDT
In force
3 hr
Issued by
NWS Tallahassee, FL
Area
Storm-based polygon

County Decatur County, GA

The radar

The Tallahassee radar (KTLH), 65 km from the middle of the area, began a volume at 23:20 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 11.3 hours before the alert went out and 66 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, Tallahassee Rgnl, FL at 12:00Z on 2021-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 799 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, Tallahassee Rgnl, FL at 12:00Z on 2021-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 square meters per square second.19395878Sfc1 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
799 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
866 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.1

Open this sounding in Storm Lab

The text

As transmitted.

180 
WGUS82 KTAE 112319
FLSTAE

Flood Advisory
National Weather Service Tallahassee FL
719 PM EDT Tue May 11 2021

GAC087-120230-
/O.NEW.KTAE.FA.Y.0021.210511T2319Z-210512T0230Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Decatur GA-
719 PM EDT Tue May 11 2021

The National Weather Service in Tallahassee has issued a

* Flood Advisory for...
  East Central Decatur County in southwestern Georgia...

* Until 1030 PM EDT.

* At 719 PM EDT, Doppler radar indicated heavy rain due to 
  thunderstorms. Minor flooding is ongoing or expected to begin 
  shortly in the advisory area. Between 2 and 3.5 inches of rain 
  have fallen in the last hour.

Some locations that will experience flooding include...
  Bainbridge and West Bainbridge.

Additional rainfall of 2 to 3 inches is expected over the area. This 
additional rain will result in minor flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be alert for flooded roadways. Turn around, don't drown when 
encountering flooded roads.

&&

LAT...LON 3099 8460 3103 8445 3100 8438 3090 8438
      3088 8462

$$

Godsey

The office that day

Everything else NWS Tallahassee, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 6:55 PM EDTSpecial Weather StatementTAESeminole50 min
May 11, 7:43 PM EDTSpecial Weather StatementTAEDecatur, Grady32 min
May 11, 7:45 PM EDTFlash Flood WarningTAEDecatur3 hr

Nearby

Areal Flood Advisories in Georgia, 2021Every areal flood advisory in 2021

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.