Alert archive / South Carolina / Mesoscale Discussions in 2012
Mesoscale Discussion 2173
The Storm Prediction Center issued this mesoscale discussion at Dec 17, 2012, 2:28 PM EST for Effingham County, Screven County, Georgia; 9 counties in South Carolina. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- Dec 17, 2012, 2:28 PM EST (19:28 UTC)
- Expired
- Dec 17, 2012, 4:00 PM EST
- In force
- 92 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
Counties Effingham County, GA, Screven County, GA, Allendale County, SC, Beaufort County, SC, Berkeley County, SC, Charleston County, SC, Colleton County, SC, Dorchester County, SC, Georgetown County, SC, Hampton County, SC, Jasper County, SC
The radar
The Charleston,SC radar (KCLX), 65 km from the middle of the area, began a volume at 19:31 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Charleston AFB, SC (KCHS), launched 12:00Z, 7.5 hours before the alert went out and 37 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 562 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- 79 m²/s²
- 0-3 km storm-relative helicity
- 168 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
550
ACUS11 KWNS 171929
SWOMCD
SPC MCD 171928
SCZ000-GAZ000-172100-
MESOSCALE DISCUSSION 2173
NWS STORM PREDICTION CENTER NORMAN OK
0128 PM CST MON DEC 17 2012
AREAS AFFECTED...SRN AND ERN SC
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 171928Z - 172100Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...STORMS CONTINUE TO INCREASE IN INTENSITY UPSTREAM...AND A
WATCH APPEARS LIKELY MAINLY FOR DAMAGING WINDS.
DISCUSSION...SURFACE ANALYSIS SHOWS TEMPERATURES IN THE LOWER 70S
AND DEWPOINTS IN THE MID 60S F ACROSS SERN GA AHEAD OF THE LINE OF
STORMS WHICH HAVE SHOWN SIGNS OF BROAD ROTATION AT TIMES. DEEP LAYER
SHEAR PROFILES REMAIN STRONG AND THESE STORMS SHOULD CONTINUE TO BE
AIDED BY FORCING ASSOCIATED WITH THE UPPER TROUGH AS THEY TRAVEL
ACROSS SRN SC. DAMAGING WIND GUSTS WILL BE POSSIBLE...AND A TORNADO
CANNOT BE RULED OUT.
..JEWELL/CORFIDI.. 12/17/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...ILM...CHS...CAE...
LAT...LON 32058045 32078101 32268148 32718171 33078133 33448012
33497963 33387911 33167908 32627959 32058045SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 17, 11:49 AM EST | Mesoscale Discussion | SPC | Appling, Atkinson, Bacon, Baker, Ben Hill, Berrien and 31 more | 116 min |
| Dec 17, 1:30 PM EST | Tornado Watch | SPC | Appling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 35 more | 5 hr |
| Dec 17, 2:55 PM EST | Tornado Watch | SPC | Beaufort, Berkeley, Charleston, Colleton, Dorchester, Hampton and 1 more | 2 hr |
Nearby
Mesoscale Discussions in South Carolina, 2012Mesoscale Discussions in Georgia, 2012Every mesoscale discussion in 2012
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.