Alert archive / Georgia / Tornado Watches in 2019

Tornado Watch 705

December 17, 20195 counties in Florida; 25 counties in Georgia

The Storm Prediction Center issued this tornado watch at Dec 17, 2019, 11:58 AM EST for 5 counties in Florida; 25 counties in Georgia. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Dec 17, 2019, 11:58 AM EST (16:58 UTC)
Expired
Dec 17, 2019, 5:06 PM EST
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt
All 30 counties

Baker County, FL, Columbia County, FL, Hamilton County, FL, Nassau County, FL, Suwannee County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Bryan County, GA, Camden County, GA, Charlton County, GA, Chatham County, GA, Clinch County, GA, Coffee County, GA, Echols County, GA, Evans County, GA, Glynn County, GA, Jeff Davis County, GA, Liberty County, GA, Long County, GA, McIntosh County, GA, Montgomery County, GA, Pierce County, GA, Tattnall County, GA, Telfair County, GA, Toombs County, GA, Ware County, GA, Wayne County, GA, Wheeler County, GA

The radar

The Moody AFB radar (KVAX), 49 km from the middle of the area, began a volume at 16:59 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Dec 17, 12:00 PM ESTTornado Warning Tornado observedJAXCoffee33 min
Dec 17, 12:05 PM ESTTornado Warning Tornado observedConsiderable damage threatFFCTelfair27 min
Dec 17, 12:28 PM ESTSevere Thunderstorm WarningJAXJeff Davis29 min
Dec 17, 1:22 PM ESTSevere Thunderstorm WarningCHSTattnall53 min
Dec 17, 2:36 PM ESTSevere Thunderstorm WarningJAXClinch, Echols24 min
Dec 17, 2:48 PM ESTSevere Thunderstorm WarningJAXAppling, Brantley, Clinch, Pierce, Ware42 min
Dec 17, 3:00 PM ESTSevere Thunderstorm WarningJAXCharlton, Clinch, Echols, Ware45 min
Dec 17, 3:26 PM ESTSevere Thunderstorm WarningJAXBrantley, Pierce, Wayne34 min
Dec 17, 3:39 PM ESTSevere Thunderstorm WarningJAXBrantley, Camden, Charlton, Clinch, Glynn, Ware51 min
Dec 17, 4:20 PM ESTSevere Thunderstorm WarningJAXNassau25 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Jacksonville, FL (KJAX), launched 12:00Z, 5.0 hours before the alert went out and 86 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, Jacksonville, FL at 12:00Z on 2019-12-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 845 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, Jacksonville, FL at 12:00Z on 2019-12-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 193 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
845 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
606 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
193 m²/s²
0-3 km storm-relative helicity
197 m²/s²
Significant tornado parameter
0.9
Supercell composite
6.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 16, 9:58 PM ESTMesoscale DiscussionSPCEscambia, Holmes, Okaloosa, Santa Rosa, Walton92 min
Dec 17, 3:13 AM ESTMesoscale DiscussionSPCHolmes, Santa Rosa92 min
Dec 17, 7:54 AM ESTTornado WatchSPCBay, Calhoun, Franklin, Gadsden, Gulf, Holmes and 10 more7 hr
Dec 17, 10:29 AM ESTMesoscale DiscussionSPCBay, Calhoun, Gadsden, Jackson, Jefferson, Leon and 1 more91 min
Dec 17, 11:32 AM ESTMesoscale DiscussionSPCBaker, Columbia, Hamilton, Lafayette, Madison, Nassau and 2 more88 min
Dec 17, 2:58 PM ESTMesoscale DiscussionSPCBaker, Columbia, Duval, Hamilton, Lafayette, Nassau and 2 more92 min
Dec 17, 3:04 PM ESTMesoscale DiscussionSPCBrevard, Citrus, DeSoto, Flagler, Hardee, Hernando and 15 more116 min
Dec 16, 7:05 PM ESTMesoscale DiscussionSPCBartow, Catoosa, Chattooga, Dade, Floyd, Gordon and 4 more55 min
Dec 17, 12:11 AM ESTMesoscale DiscussionSPCCarroll, Chattahoochee, Clayton, Coweta, DeKalb, Douglas and 16 more64 min

Nearby

Tornado Watches in Georgia, 2019Tornado Watches in Florida, 2019Every tornado watch in 2019

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.