Alert archive / Alabama / Mesoscale Discussions in 2012
Mesoscale Discussion 2071
The Storm Prediction Center issued this mesoscale discussion at Oct 17, 2012, 11:10 PM CDT for 30 counties in Alabama. It was in force for 95 min.
The area
The outline as issued.
The facts
- Issued
- Oct 17, 2012, 11:10 PM CDT (04:10 UTC)
- Expired
- Oct 18, 2012, 12:45 AM CDT
- In force
- 95 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 60%
All 30 counties
Bibb County, AL, Blount County, AL, Calhoun County, AL, Cherokee County, AL, Chilton County, AL, Coosa County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lawrence County, AL, Limestone 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
The radar
The Birmingham radar (KBMX), 71 km from the middle of the area, began a volume at 04:13 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
Birmingham, AL (KBMX), launched 00:00Z, 4.2 hours before the alert went out and 70 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
- 1776 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 35 m²/s²
- 0-3 km storm-relative helicity
- 125 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
109
ACUS11 KWNS 180410
SWOMCD
SPC MCD 180410
ALZ000-180545-
MESOSCALE DISCUSSION 2071
NWS STORM PREDICTION CENTER NORMAN OK
1110 PM CDT WED OCT 17 2012
AREAS AFFECTED...PARTS OF NRN AND CENTRAL AL
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 180410Z - 180545Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...BAND OF STORMS ADVANCING EWD INTO AL MAY REQUIRE NEW WW
ISSUANCE...
DISCUSSION...LATEST RADAR IMAGERY SHOWS A BAND OF STORMS WITH
EMBEDDED BOWS/LEWPS MARCHING EWD ACROSS NRN MS ATTM. THE DOWNSTREAM
AIRMASS ACROSS AL INCLUDES A MUCH MORE STABLE BOUNDARY
LAYER...SUGGESTING THAT SEVERE POTENTIAL SHOULD SLOWLY DIMINISH WITH
TIME AS STORMS BECOME INCREASINGLY ELEVATED.
STILL...GIVEN THE WELL-ORGANIZED NATURE OF THE LINE -- OWING TO THE
VERY DYNAMIC MID-LEVEL SYSTEM...EXPECT SOME THREAT FOR LOCALLY
DAMAGING GUSTS WILL LIKELY PERSIST FOR AT LEAST A COUPLE MORE HOURS.
THUS...NEW WW MAY BE REQUIRED.
..GOSS/CORFIDI.. 10/18/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...HUN...
LAT...LON 34908563 34058549 32878621 32288740 32528833 34018810
34958729 34908563SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 17, 8:43 PM CDT | Severe Thunderstorm Watch | SPC | Colbert, Franklin, Lauderdale | 4 hr |
| Oct 18, 1:09 AM CDT | Mesoscale Discussion | SPC | Choctaw, Clarke, Mobile, Monroe, Washington | 96 min |
| Oct 18, 2:40 AM CDT | Mesoscale Discussion | SPC | Choctaw, Clarke, Conecuh, Escambia, Marengo, Monroe and 2 more | 65 min |
Nearby
Mesoscale Discussions in Alabama, 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.