Alert archive / Georgia / Wind Chill Advisories in 2020

Wind Chill Advisory 3, NWS Jacksonville, FL

December 24, 202010 counties in Florida; 14 counties in Georgia

NWS Jacksonville, FL issued this wind chill advisory at Dec 24, 2020, 1:41 PM EST for 10 counties in Florida; 14 counties in Georgia. It took effect at Dec 25, 2020, 2:00 AM EST. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Dec 24, 2020, 1:41 PM EST (18:41 UTC)
In effect from: Dec 25, 2020, 2:00 AM EST
Expired: Dec 25, 2020, 9:00 AM EST
In force: 7 hr
Issued by: NWS Jacksonville, FL

All 24 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Marion County, FL, Nassau County, FL, Suwannee County, FL, Union County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Coffee County, GA, Echols County, GA, Glynn County, GA, Jeff Davis County, GA, Pierce County, GA, Ware County, GA, Wayne County, GA

The radar

The Jacksonville radar (KJAX), 59 km from the middle of the area, began a volume at 18:44 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, 6.7 hours before the alert went out and 198 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 944 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 346 m²/s²
0-3 km storm-relative helicity: 416 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 wind chill advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Jacksonville, FL wrote its last area forecast discussion before this wind chill advisory went out at Dec 24, 12:43 PM EST, 58 minutes earlier.

Area forecast discussion, Dec 24, 12:43 PM EST, 58 minutes before

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In the hours before

Local storm report, Dec 24, 12:24 PM EST, 1 hour 17 minutes before

PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
1224 PM EST THU DEC 24 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1210 PM     NON-TSTM WND GST GAINESVILLE             29.67N 82.34W
12/24/2020  M41 MPH          ALACHUA            FL   MESONET

            ELEVATED MESONET OBSERVATION ON THE UNIVERSITY OF FLORIDA
            CAMPUS REPORTED WIND GUST TO 41 MPH FROM THE SOUTH.

&&

JHESS

Local storm report, Dec 24, 1:08 PM EST, 33 minutes before

PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
108 PM EST THU DEC 24 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1223 PM     NON-TSTM WND GST MAYPORT                 30.38N 81.41W
12/24/2020  M41 MPH          DUVAL              FL   ASOS

            MAYPORT NAVAL STATION ASOS MEASURED A WIND GUST OF 41 MPH
            FROM THE SOUTH.

&&

DDOLAN

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 24, 3:32 AM EST	Gale Warning	JAX		35 hr
Dec 24, 3:34 AM EST	Rip Current Statement	JAX	Duval, Flagler, Nassau	10 hr
Dec 24, 3:36 AM EST	Freeze Watch	JAX	Duval, Flagler, Nassau	23 hr
Dec 24, 3:36 AM EST	Hard Freeze Watch	JAX	Alachua, Baker, Bradford, Gilchrist, Marion, Nassau and 2 more	23 hr
Dec 24, 1:50 PM EST	Freeze Warning	JAX	Alachua, Baker, Bradford, Gilchrist, Nassau, Suwannee and 1 more	19 hr
Dec 24, 4:02 PM EST	Severe Thunderstorm Warning	JAX	Hamilton	43 min
Dec 24, 4:18 PM EST	Special Weather Statement	JAX	Suwannee	42 min
Dec 24, 4:39 PM EST	Severe Thunderstorm Warning	JAX	Baker, Columbia, Hamilton, Suwannee	66 min
Dec 24, 5:24 PM EST	Special Weather Statement	JAX	Alachua, Gilchrist, Union	51 min
Dec 24, 5:42 PM EST	Severe Thunderstorm Warning	JAX	Alachua, Baker, Bradford, Clay, Columbia, Duval and 3 more	48 min
Dec 24, 6:08 PM EST	Severe Thunderstorm Warning	JAX	Alachua, Putnam	37 min
Dec 24, 6:19 PM EST	Special Weather Statement	JAX	Marion	41 min
Dec 24, 6:28 PM EST	Severe Thunderstorm Warning	JAX	Baker, Bradford, Clay, Duval, Nassau, Putnam and 1 more	62 min
Dec 24, 6:31 PM EST	Special Marine Warning	JAX		89 min
Dec 24, 6:48 PM EST	Special Weather Statement	JAX	Putnam	42 min
Dec 24, 3:25 PM EST	Special Weather Statement	JAX	Atkinson, Coffee, Jeff Davis	65 min
Dec 24, 4:25 PM EST	Special Weather Statement	JAX	Appling, Atkinson, Bacon, Coffee, Jeff Davis, Pierce	50 min
Dec 24, 5:14 PM EST	Special Weather Statement	JAX	Brantley, Pierce, Wayne	46 min
Dec 24, 5:33 PM EST	Severe Thunderstorm Warning	JAX	Brantley, Camden, Charlton, Glynn, Pierce, Ware and 1 more	57 min

Nearby

Wind Chill Advisories in Georgia, 2020 Wind Chill Advisories in Florida, 2020 Every wind chill advisory in 2020

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.