Alert archive / Georgia / Mesoscale Discussions in 2003
Mesoscale Discussion 480
The Storm Prediction Center issued this mesoscale discussion at Apr 17, 2003, 3:13 PM EDT for 19 counties in Georgia; 4 counties in Tennessee. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 17, 2003, 3:13 PM EDT (19:13 UTC)
- Expired
- Apr 17, 2003, 5:45 PM EDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
All 23 counties
Bartow County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Cobb County, GA, Dade County, GA, Dawson County, GA, Douglas County, GA, Floyd County, GA, Forsyth County, GA, Fulton County, GA, Gordon County, GA, Haralson County, GA, Murray County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Walker County, GA, Whitfield County, GA, Bledsoe County, TN, Bradley County, TN, Hamilton County, TN, Sequatchie County, TN
The radar
The Northeast Alabama radar (KHTX), 109 km from the middle of the area, began a volume at 19:16 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
Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 7.2 hours before the alert went out and 150 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
- 1324 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 53 m²/s²
- 0-3 km storm-relative helicity
- 105 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
562 ACUS11 KWNS 171914 SWOMCD SPC MCD 171913 GAZ000-TNZ000-ALZ000-172145- MESOSCALE DISCUSSION 0480 NWS STORM PREDICTION CENTER NORMAN OK 0213 PM CDT THU APR 17 2003 AREAS AFFECTED...PARTS OF MIDDLE/ERN TN ...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 171913Z - 172145Z THUNDERSTORMS LIKELY WILL INTENSIFY NEXT FEW HOURS...BUT WW IS NOT CURRENTLY ANTICIPATED AS ENVIRONMENT IS EXPECTED TO BECOME ONLY MARGINALLY SUPPORTIVE OF SEVERE THREAT. NORTHWESTERLY MID-LEVEL SPEED MAXIMUM...WEST OF NEGATIVELY TILTED SHORT WAVE TROUGH AXIS OVER THE LOWER OHIO VALLEY...APPEARS TO BE SHIFTING SOUTHEASTWARD ACROSS WESTERN TENNESSEE...MUCH AS SUGGESTED BY MODELS. EXIT REGION OF JET STREAK IS PROGGED TO NOSE INTO THE SOUTHERN APPALACHIANS BY 18/00Z...AND WILL BEGIN TO ENHANCE FORCING FOR UPWARD VERTICAL MOTION AND VERTICAL SHEAR PROFILES FROM PARTS OF MIDDLE TENNESSEE INTO NORTHERN GEORGIA WITHIN THE NEXT FEW HOURS. BOUNDARY LAYER IS WARMING THROUGH THE 70S ALONG MOISTURE GRADIENT WEST OF LOW-LEVEL MOISTURE AXIS EXTENDING FROM THE EASTERN GULF COAST INTO GEORGIA...NORTHWEST OF ATLANTA...ON INTO THE VICINITY OF CHATTANOOGA TN...WHERE CONVECTIVE DEVELOPMENT APPEARS TO BE UNDERWAY. AS LIFT ASSOCIATED WITH LOW-LEVEL WARM ADVECTION ALONG THE WESTERN SLOPES OF THE SOUTHERN APPALACHIANS BECOMES ENHANCED...ONGOING ACTIVITY LIKELY WILL BEGIN TO INTENSIFY. VERTICAL SHEAR PROFILES WILL BECOME SUFFICIENT FOR UPDRAFT ROTATION...WHICH WILL CONTRIBUTE TO POTENTIAL FOR HAIL/GUSTY WINDS WITH CELLS DEVELOPING IN ENVIRONMENT WITH MEAN MIXED LAYER CAPE OF 500 TO 1000 J/KG. ..KERR.. 04/17/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN... 35458559 35818510 35388485 34668466 34378401 33658434 33438483 33848547
Nearby
Mesoscale Discussions in Georgia, 2003Mesoscale Discussions in Tennessee, 2003Every mesoscale discussion in 2003
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.