Alert archive / Florida / Flash Flood Warnings in 2021

Flash Flood Warning 39, NWS Tallahassee, FL

September 21, 2021Leon County, Florida

NWS Tallahassee, FL issued this flash flood warning at Sep 21, 2021, 3:48 PM EDT for Leon County, Florida. It was in force for 57 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Sep 21, 2021, 3:48 PM EDT (19:48 UTC)
Expired
Sep 21, 2021, 4:45 PM EDT
In force
57 min
Issued by
NWS Tallahassee, FL
Area
Storm-based polygon
Flood severity
None

County Leon County, FL

The radar

The Tallahassee radar (KTLH), 8 km from the middle of the area, began a volume at 19:49 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.

What was reported inside it

TimeReportWhereRemark
Sep 21, 3:59 PM EDTFLASH FLOOD1 Nw Innovation Park, FLROAD UNDER WATER AT JACKSON BLUFF ROAD AND DUPREE STREET.
Sep 21, 4:00 PM EDTFLASH FLOOD1 W Doak Campbell Stadi, FLWATER OVER THE ROAD IN THE 200 BLOCK OF S OCALA ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 7.8 hours before the alert went out and 6 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 2021-09-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 675 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 2021-09-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 square meters per square second.1939Sfc1 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
675 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
747 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
41 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

695 
WGUS52 KTAE 211948
FFWTAE
FLC073-212045-
/O.NEW.KTAE.FF.W.0039.210921T1948Z-210921T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tallahassee FL
348 PM EDT Tue Sep 21 2021

The National Weather Service in Tallahassee has issued a

* Flash Flood Warning for...
  Central Leon County in Big Bend Florida...

* Until 445 PM EDT.

* At 348 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen in the last 45 minutes. The expected rainfall 
  rate is 1.5 to 3 inches in 1 hour. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Tallahassee, Florida A And M, Florida State University, Doak 
  Campbell Stadium, Tallahassee Comm College, State Capital Complex, 
  Governors Square Mall, Kleman Plaza, Indian Head Acres, 
  Tallahassee Memorial Hosp, Leon County Civic Center, Lake Ella, 
  Winthrop Park, Bragg Stadium, Levy Park, North Florida 
  Fairgrounds, Tallahassee Mall, Gaither Community Center, Springsax 
  Park and Belair.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3053 8437 3054 8431 3053 8423 3050 8415
      3043 8415 3036 8416 3033 8421 3034 8428
      3037 8436 3043 8440

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1.5-3 INCHES IN 1 HOUR

$$

WD

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 21, 10:35 AM EDTSpecial Marine WarningTAE85 min
Sep 21, 4:50 PM EDTAreal Flood AdvisoryTAEJefferson115 min

Nearby

Flash Flood Warnings in Florida, 2021Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.