Atkinson Tornado 12/2/2018

Tornadoes:

Tornado - LOCATION COUNTY NAME Date December 2, 2018 Time (Local) 2:11 PM - 2:16 PM EF Rating 0 Est. Peak Winds 65 -75 mph Path Length Estimated 2 miles Max Width 50 yards Injuries/Deaths 0 Summary: In the early afternoon hours of Sunday December 2, 2018 a strengthening line of thunderstorms moved northeast into Atkinson and produced 2 brief QLCS tornados. The first tornado caused damage to trees south of Highway 82 between County Road 38 and Lazy Nine Road. The second brief tornado caused minor property damage just north of Highway 82 near Pearson. Both tornadoes had damage consistent with an EF-0 rating.  Track Map Downloadable KMZ File

The Enhanced Fujita (EF) Scale classifies tornadoes into the following categories:

EF0 Weak 65-85 mph	EF1 Moderate 86-110 mph	EF2 Significant 111-135 mph	EF3 Severe 136-165 mph	EF4 Extreme 166-200 mph	EF5 Catastrophic 200+ mph

Photos & Video

Header

Atkinson County GA Courtesy of Atkinson County Emergency Management

Pearson, GA Courtesy of Atkinson County Emergency Management	Pearson, GA Courtesy of Atkinson County Emergency Management	Pearson, GA Courtesy of Atkinson County Emergency Management	Atkinson county, GA Courtesy of Atkinson County Emergency Management

Radar

A debris ball signature is visible at the 1911Z Sails cut located 2 miles south of US82 and about 7 miles west of Pearson in Atkinson county Georgia. This debris ball signature coincides with base reflectivity values of 50 to 55 DBZ along with a rotational velocity of over 45 knots where the first brief tornado formed.

Figure 1: KVAX Base Reflectivity Image at the 1911Z Sails Cut	Figure 2: KVAX Base Velocity Image at the 1911Z Sails Cut	Figure 3: KVAX Correlation Coefficient Image at the 1911Z Sails Cut	Figure 4: KVAX Imagery of Base Reflectivity and Velocity from 1903Z to 1954Z

Storm Reports

PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
446 PM EST SUN DEC 2 2018

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

0214 PM     TORNADO          6 SE WILLACOOCHEE       31.29N 82.97W 
12/02/2018                   Atkinson           GA   OFFICIAL NWS OBS

            RADAR OBSERVATIONS INDICATED A TDS SOUTH OF HIGHWAY 82 IN
            MOSTLY RURAL TERRAIN. NO DAMAGE REPORTS HAVE BEEN 
            REPORTED AT THIS TIME. TIME ESTIMATED USING RADAR DATA. 

PRELIMINARY LOCAL STORM REPORT...CORRECTED
National Weather Service Jacksonville FL
344 PM EST MON DEC 3 2018

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

0214 PM     TORNADO          6 SE WILLACOOCHEE       31.29N 82.97W 
12/02/2018  F0               Atkinson           GA   EMERGENCY MNGR  

            ATKINSON COUNTY EMERGENCY MANAGEMENT REPORTS TREES BROKEN
            OFF AT THE TOPS AND DAMAGE CONSISTENT WITH EF-0 INTENSITY
            IN BETWEEN COUNTY ROAD 38 AND LAZY NINE ROAD TO THE SOUTH
            OF U.S. HIGHWAY 82. TIME ESTIMATED USING RADAR DATA. 

PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
141 PM EST THU DEC 13 2018

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

0230 PM     TORNADO          1 NNW PEARSON           31.31N 82.86W 
12/02/2018                   Atkinson           GA   PUBLIC          

            HOME SECURITY CAMERAS CAPTURED A TORNADO MOVING THROUGH 
            THE YARD OF THE PROPERTY AND CAUSED MINOR DAMAGE TO THE 
            HOUSE. BASED ON THIS INFORMATION, THE TORNADO WAS GIVEN 
            AN ESTIMATED EF-0 RATING WITH NO ADDITIONAL SURVEYING 
            EXPECTED.

Environment

Synoptic Overview

On Sunday morning of Dec 2, 2018 the 12Z WPC surface analysis displayed a cold frontal boundary draped from near Chattanooga, TN southward towards the Gulf coast to near Mobile, AL. Ahead of this front, warm moist air streamed northeastward with dew points in the mid to upper 60s across central and southern GA. A strong low level jet over the NE Gulf of Mexico & FL panhandle was evident on the 12Z analysis with winds from the southwest approaching 50 knots at 850mb. Meanwhile, a vigorous short wave was rotating around the base of a mid level 500mb trough was positioned over the southern Mississippi Valley. Embedded wind speeds up to 60 to 70 knots were just upstream of the region area the 12Z analysis.

Figure 1: WPC 12Z Surface Analysis Map for December 2, 2018	Figure 2: SPC 12Z Upper Air Map for December 2, 2018	Figure 3: SPC 12Z Day 1 Convective Outlook with a Slight risk over SE GA

Mesoanalysis 

The 12Z Jacksonville sounding depicted high levels of instability, shear and veering low level winds. The sounding contained MU Cape values over 2,600 J/Kg, Surface Relative Helicity values close to 300 m2/s2, and a Precipitable Water of 1.80 inches which was well above the 90th percentile for the day, indicating a deep moist environment available for thunderstorm updrafts. The Storm Predication center issued a Mesoscale Discussion at 12Z mentioning isolated severe storms ongoing over central and southwest Georgia may spread into southeast Georgia in the morning and noting that high dewpoints in the upper 60s were advecting northeastward with southwesterly flow measured at 50 knots at 1 km above the surface helping to erode the cooler outflow air with effective SRH values over southeast Georgia rising into the morning and increasing the threat for damaging winds and a brief tornado.

At 15Z, A tornado watch was issued by the Storm Predication center for southern Georgia into southern South Carolina until 23Z. The watch included all of the southeast Georgia counties within the Jacksonville area of responsibility with the primary threats including a couple tornadoes, scattered wind gusts up to 70 mph, and isolated large hail up to 1 inch in diameter possible. At 1730Z, another Mesoscale Discussion was issued by the Storm Prediction Center noting that the threat for damaging winds and couple tornadoes had not changed despite the lack of significant boundary-layer heating. A view of the the Storm Predication Center's 18Z mesoanalysis revealed Surface Based Cape values ranging from 1,000 to 1,500 J/kg over southeast Georgia along with effective Bulk Shear Values over 50 knots just north of the Florida/Georgia state line. The persistence of shear and instability in the atmosphere over southeast Georgia set the stage for the line of thunderstorms moving into Atkinson county Georgia to form a brief tornadoes.

Figure 4: Jacksonville 12Z Upper Air Sounding	Figure 5: SPC Mesoscale Discussion #1692 over Southeast Georgia at 12Z	Figure 6: Tornado Watch #437 issued at 15Z for Southeast Georgia

Figure 7:  SPC Mesoscale Discussion #1693 over Southeast Georgia at 1732Z	Figure 8: SPC 18Z Mesoanalysis of Surface Based Cape	Figure 9: SPC 18Z Mesoanalysis of Effective Bulk Shear