Alert archive / Alabama / Mesoscale Discussions in 2016
Mesoscale Discussion 77
The Storm Prediction Center issued this mesoscale discussion at Feb 2, 2016, 2:40 PM CST for 33 counties in Alabama; 16 counties in Kentucky; 30 counties in Tennessee. It was in force for 95 min.
The area
The outline as issued.
The facts
- Issued
- Feb 2, 2016, 2:40 PM CST (20:40 UTC)
- Expired
- Feb 2, 2016, 4:15 PM CST
- In force
- 95 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 79 counties
Autauga County, AL, Bibb County, AL, Blount County, AL, Chilton County, AL, Colbert County, AL, Cullman County, AL, Dallas County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Hale County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Lowndes County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Talladega County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Allen County, KY, Barren County, KY, Breckinridge County, KY, Butler County, KY, Cumberland County, KY, Edmonson County, KY, Grayson County, KY, Green County, KY, Hardin County, KY, Hart County, KY, Larue County, KY, Logan County, KY, Metcalfe County, KY, Monroe County, KY, Simpson County, KY, Warren County, KY, Bedford County, TN, Cannon County, TN, Cheatham County, TN, Clay County, TN, Coffee County, TN, Davidson County, TN, DeKalb County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hickman County, TN, Jackson County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, Moore County, TN, Putnam County, TN, Robertson County, TN, Rutherford County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Warren County, TN, White County, TN, Williamson County, TN, Wilson County, TN
The radar
The Northeast Alabama radar (KHTX), 69 km from the middle of the area, began a volume at 20:40 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 12:00Z, 8.7 hours before the alert went out and 162 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
- 2 J/kg
- Mixed-layer CIN
- -287 J/kg
- Mixed-layer LCL
- 485 m above ground
- 0-6 km bulk shear
- 71 kt
- 0-1 km storm-relative helicity
- 346 m²/s²
- 0-3 km storm-relative helicity
- 387 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
908
ACUS11 KWNS 022041
SWOMCD
SPC MCD 022040
TNZ000-KYZ000-ALZ000-022215-
MESOSCALE DISCUSSION 0077
NWS STORM PREDICTION CENTER NORMAN OK
0240 PM CST TUE FEB 02 2016
AREAS AFFECTED...PORTIONS OF S-CNTRL KY...MIDDLE TN...AND NRN/CNTRL
AL
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 022040Z - 022215Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...AN INCREASING THREAT FOR DAMAGING WIND GUSTS AND ISOLATED
TORNADOES...A COUPLE OF WHICH COULD BE STRONG...IS EXPECTED THROUGH
THE REMAINDER OF THE AFTERNOON AND INTO THE EARLY EVENING. TORNADO
WATCH ISSUANCE IS LIKELY BY 22Z.
DISCUSSION...ONGOING STRONG TO SEVERE THUNDERSTORMS ACROSS WRN TN
AND NRN/CNTRL MS THAT HAVE FORMED AHEAD OF A SFC COLD FRONT WILL
CONTINUE MOVING NEWD OVER THE NEXT SEVERAL HOURS. LOW- AND MID-LEVEL
SHEAR PROFILES REMAIN QUITE FAVORABLE FOR TORNADIC SUPERCELL
POTENTIAL...WITH AREA VWPS INDICATING 0-1 KM SRH IN EXCESS OF 200
M2/S2 ACROSS THE MCD AREA...AND IN SOME CASES APPROACHING 400 M2/S2.
THE MAIN LIMITING FACTOR REMAINS THE THERMODYNAMIC PROFILE...WITH
20Z RAP MESOANALYSIS ESTIMATING MUCAPE GENERALLY BETWEEN 100-500
J/KG...DECREASING FROM S TO N. HOWEVER...CONTINUED NWD TRANSPORT OF
MOISTURE IN ASSOCIATION WITH A STRONG /50-60 KT/ LOW-LEVEL JET ALONG
WITH STEEPING MID-LEVEL LAPSE RATES SHOULD ERODE THE LINGERING
CAPPING EVIDENT AROUND 600 MB IN THE 18Z KBMX SOUNDING. GIVEN
TENDENCY FOR CONVECTION TO BECOME MORE LINEAR LATER THIS
AFTERNOON...DAMAGING WINDS WILL BE A THREAT...WITH ISOLATED
TORNADOES ALSO POSSIBLE GIVEN THE STRENGTH OF THE LOW-LEVEL SHEAR. A
STRONG TORNADO OR TWO MAY NOT BE OUT OF THE QUESTION OVER THE NEXT
SEVERAL HOURS...PARTICULARLY ACROSS PORTIONS OF WRN AL INTO MIDDLE
TN WHERE THE MOST FAVORABLE OVERLAP OF STRONG SHEAR WITH SUFFICIENT
INSTABILITY EXISTS.
..GLEASON/GOSS.. 02/02/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...LMK...OHX...BMX...HUN...
LAT...LON 32368830 34928799 36628699 37878655 37858548 36818521
34988563 33438608 32018659 32318745 32368830SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 2, 12:50 PM CST | Mesoscale Discussion | SPC | Baldwin, Butler, Clarke, Conecuh, Covington, Escambia and 3 more | 55 min |
| Feb 2, 1:18 PM CST | Tornado Watch | SPC | Baldwin, Choctaw, Clarke, Mobile, Monroe, Washington and 1 more | 6 hr |
| Feb 2, 3:10 PM CST | Tornado Watch | SPC | Bibb, Blount, Chilton, Colbert, Cullman, Dallas and 23 more | 7 hr |
| Feb 2, 5:18 PM CST | Mesoscale Discussion | SPC | Baldwin, Choctaw, Clarke, Mobile, Monroe, Washington and 1 more | 117 min |
| Feb 2, 5:31 PM CST | Mesoscale Discussion | SPC | Autauga, Bibb, Blount, Chilton, Colbert, Cullman and 26 more | 119 min |
| Feb 2, 9:54 AM CST | Mesoscale Discussion | SPC | Ballard, Carlisle, Fulton, Hickman, McCracken | 96 min |
| Feb 2, 12:22 PM CST | Tornado Watch | SPC | Ballard, Caldwell, Calloway, Carlisle, Christian, Crittenden and 16 more | 9 hr |
Nearby
Mesoscale Discussions in Alabama, 2016Mesoscale Discussions in Tennessee, 2016Mesoscale Discussions in Kentucky, 2016Every mesoscale discussion in 2016
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.