Alert archive / Georgia / Mesoscale Discussions in 2015

Mesoscale Discussion 1921

November 2, 20158 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Nov 2, 2015, 4:37 PM EST for 8 counties in Georgia. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
Nov 2, 2015, 4:37 PM EST (21:37 UTC)
Expired
Nov 2, 2015, 5:30 PM EST
In force
53 min
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Bryan County, GA, Bulloch County, GA, Candler County, GA, Chatham County, GA, Effingham County, GA, Evans County, GA, Long County, GA, Tattnall County, GA

The radar

The Charleston,SC radar (KCLX), 83 km from the middle of the area, began a volume at 21:40 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

Charleston AFB, SC (KCHS), launched 12:00Z, 9.6 hours before the alert went out and 182 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, Charleston AFB, SC at 12:00Z on 2015-11-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 140 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Charleston AFB, SC at 12:00Z on 2015-11-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 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
140 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

604 
ACUS11 KWNS 022137
SWOMCD
SPC MCD 022137 
SCZ000-GAZ000-022230-

MESOSCALE DISCUSSION 1921
NWS STORM PREDICTION CENTER NORMAN OK
0337 PM CST MON NOV 02 2015

AREAS AFFECTED...PORTIONS OF SERN GA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 022137Z - 022230Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...THE NEED FOR AN ADDITIONAL TORNADO WATCH APPEARS LOW FOR
AREAS DOWNSTREAM OF TORNADO WATCH 530.  AN ISOLD THREAT FOR WIND
DAMAGE MAY CONTINUE BEYOND THE ERN BOUND OF THE TORNADO WATCH.

DISCUSSION...THE PAST FEW HOURS OF SURFACE OBSERVATIONS OVER PARTS
OF SERN GA AND THE SAVANNAH RIVER VALLEY SHOW A WARM/MOIST AIRMASS
OVER THE GA COASTAL PLAIN.  WEAK SURFACE WINDS /AOB 5 KT/ AT SEVERAL
OBSERVATION SITES DOWNSTREAM OF THE S-CNTRL GA ACTIVITY ARE LIKELY
INDICATIVE OF THE GRADUAL WEAKENING IN THE LOW-LEVEL MASS RESPONSE
AS A SHORTWAVE TROUGH OVER THE REGION CONTINUES TO SHEAR NEWD AND
WEAKEN.  ADEQUATELY STRONG DEEP-LAYER SHEAR /40+ KT/ WILL SUPPORT
THE POTENTIAL FOR SUPERCELL STRUCTURE PERHAPS EXITING THE EXISTING
TORNADO WATCH OVER THE NEXT 1-2 HOURS.  HOWEVER...THE LOSS OF
DIURNAL HEATING WILL ACT TO DECREASE INSTABILITY AND THE PROSPECTS
FOR AN ADDITIONAL TORNADO WATCH ARE LOW AT THIS TIME.

..SMITH/CORFIDI.. 11/02/2015

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...CHS...JAX...FFC...

LAT...LON   32528209 32798145 31988106 31718180 31898218 32528209

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 2, 6:46 AM ESTMesoscale DiscussionSPCClay, Early, Quitman2 hr
Nov 2, 11:21 AM ESTMesoscale DiscussionSPCBaker, Dougherty, Miller, Mitchell, Seminole54 min
Nov 2, 1:15 PM ESTTornado WatchSPCAtkinson, Baker, Ben Hill, Berrien, Bibb, Bleckley and 40 more6 hr
Nov 2, 2:36 PM ESTMesoscale DiscussionSPCBaker, Ben Hill, Berrien, Bibb, Bleckley, Coffee and 33 more84 min
Nov 2, 6:05 PM ESTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Berrien, Bryan, Bulloch and 12 more115 min

Nearby

Mesoscale Discussions in Georgia, 2015Every mesoscale discussion in 2015

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.