Alert archive / Florida / Areal Flood Advisories in 2021

Areal Flood Advisory 175, NWS Mobile, AL

August 20, 2021Escambia County, Florida

NWS Mobile, AL issued this areal flood advisory at Aug 20, 2021, 1:04 PM CDT for Escambia County, Florida. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Aug 20, 2021, 1:04 PM CDT (18:04 UTC)
Expired
Aug 20, 2021, 4:15 PM CDT
In force
3 hr
Issued by
NWS Mobile, AL

County Escambia County, FL

The radar

The Mobile radar (KMOB), 86 km from the middle of the area, began a volume at 18:06 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

Slidell Radar S, LA (KSIL), launched 12:00Z, 6.1 hours before the alert went out and 230 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, Slidell Radar S, LA at 12:00Z on 2021-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1321 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, Slidell Radar S, LA at 12:00Z on 2021-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
1321 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
859 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Mobile, AL wrote its last area forecast discussion before this areal flood advisory went out at Aug 20, 6:54 AM CDT, 6 hours 10 minutes earlier.

Area forecast discussion, Aug 20, 6:54 AM CDT, 6 hours 10 minutes before
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In the hours before

Special weather statement, Aug 20, 12:37 PM CDT, 27 minutes before
Special Weather Statement
National Weather Service Mobile AL
1237 PM CDT Fri Aug 20 2021

FLZ202-204-201815-
Santa Rosa Coastal FL-Escambia Coastal FL-
1237 PM CDT Fri Aug 20 2021

...A strong thunderstorm will impact portions of southwestern Santa
Rosa and south central Escambia Counties through 115 PM CDT...

At 1236 PM CDT, Doppler radar was tracking a strong thunderstorm over
Ferry Pass, moving east at 5 mph.

HAZARD...Winds in excess of 30 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Pensacola, Ferry Pass, Brent, West Pensacola, Ensley, Goulding,
Myrtle Grove and Floridatown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3041 8733 3061 8727 3061 8719 3056 8712
      3058 8704 3060 8705 3060 8704 3058 8698
      3059 8696 3049 8700 3052 8704 3044 8709
      3052 8710 3058 8718 3049 8715 3043 8717
      3039 8725
TIME...MOT...LOC 1736Z 279DEG 6KT 3050 8720

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...30 MPH
Special weather statement, Aug 20, 12:42 PM CDT, 22 minutes before
Special Weather Statement
National Weather Service Mobile AL
1242 PM CDT Fri Aug 20 2021

ALZ262-264-FLZ201-201830-
Baldwin Central AL-Baldwin Inland AL-Escambia Inland FL-
1242 PM CDT Fri Aug 20 2021

...A strong thunderstorm will impact portions of east central Baldwin
and northwestern Escambia Counties through 130 PM CDT...

At 1242 PM CDT, Doppler radar was tracking a strong thunderstorm 12
miles east of Stapleton, or 13 miles southeast of Bay Minette, moving
east at 5 mph.

HAZARD...Winds in excess of 30 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Molino.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3072 8775 3089 8772 3088 8730 3087 8730
      3085 8731 3084 8730 3080 8731 3078 8731
      3060 8732
TIME...MOT...LOC 1742Z 280DEG 5KT 3078 8758

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...30 MPH

The office that day

Everything else NWS Mobile, AL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 19, 7:38 PM CDTSevere Thunderstorm WarningMOBClarke, Washington52 min
Aug 19, 7:46 PM CDTAreal Flood AdvisoryMOBChoctaw, Clarke, Washington3 hr
Aug 19, 8:19 PM CDTSpecial Weather StatementMOBClarke56 min
Aug 19, 8:35 PM CDTFlash Flood WarningMOBChoctaw, Clarke, Washington3 hr
Aug 19, 8:52 PM CDTAreal Flood AdvisoryMOBClarke3 hr
Aug 20, 12:38 PM CDTSpecial Marine WarningMOB82 min
Aug 20, 12:42 PM CDTSpecial Weather StatementMOBBaldwin48 min
Aug 20, 2:39 PM CDTSpecial Marine WarningMOB96 min
Aug 20, 2:40 PM CDTAreal Flood AdvisoryMOBEscambia3 hr
Aug 20, 3:08 PM CDTAreal Flood AdvisoryMOBBaldwin, Escambia, Monroe112 min
Aug 20, 3:21 PM CDTAreal Flood AdvisoryMOBConecuh, Escambia114 min
Aug 20, 3:41 PM CDTAreal Flood AdvisoryMOBClarke, Washington2 hr
Aug 20, 4:19 PM CDTSevere Thunderstorm WarningMOBMobile41 min
Aug 20, 4:27 PM CDTAreal Flood AdvisoryMOBClarke, Monroe2 hr
Aug 20, 5:23 PM CDTAreal Flood AdvisoryMOBMobile4 hr
Aug 20, 6:02 PM CDTAreal Flood AdvisoryMOBMobile3 hr
Aug 20, 6:12 PM CDTSpecial Marine WarningMOB48 min
Aug 20, 6:47 PM CDTAreal Flood AdvisoryMOBBaldwin3 hr
Aug 20, 12:37 PM CDTSpecial Weather StatementMOBEscambia38 min
Aug 20, 1:51 PM CDTSpecial Weather StatementMOBOkaloosa39 min
Aug 20, 2:06 PM CDTTornado WarningMOBOkaloosa21 min
Aug 20, 2:25 PM CDTSevere Thunderstorm WarningMOBOkaloosa36 min
Aug 19, 7:01 PM CDTSpecial Weather StatementMOBWayne59 min
Aug 19, 7:50 PM CDTSpecial Weather StatementMOBWayne40 min
Aug 20, 5:21 PM CDTSpecial Weather StatementMOBGeorge39 min

Nearby

Areal Flood Advisories in Florida, 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.