Alert archive / Arkansas / Mesoscale Discussions in 2012
Mesoscale Discussion 176
The Storm Prediction Center issued this mesoscale discussion at Feb 29, 2012, 12:49 AM CST for 7 states. It was in force for 56 min.
The area
The outline as issued.
The facts
- Issued
- Feb 29, 2012, 12:49 AM CST (06:49 UTC)
- Expired
- Feb 29, 2012, 1:45 AM CST
- In force
- 56 min
- Issued by
- the Storm Prediction Center
All 176 counties
Arkansas County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clay County, AR, Cleburne County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Grant County, AR, Greene County, AR, Independence County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Ouachita County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Randolph County, AR, Saline County, AR, Sharp County, AR, St. Francis County, AR, Union County, AR, White County, AR, Woodruff County, AR, Alexander County, IL, Bond County, IL, Clay County, IL, Clinton County, IL, Edwards County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Johnson County, IL, Lawrence County, IL, Madison County, IL, Marion County, IL, Massac County, IL, Monroe County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Union County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Gibson County, IN, Knox County, IN, Pike County, IN, Posey County, IN, Spencer County, IN, Vanderburgh County, IN, Warrick County, IN, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Daviess County, KY, Fulton County, KY, Graves County, KY, Henderson County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, McLean County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Union County, KY, Webster County, KY, Bollinger County, MO, Butler County, MO, Cape Girardeau County, MO, Carter County, MO, City of Saint Louis, MO, Dunklin County, MO, Franklin County, MO, Iron County, MO, Jefferson County, MO, Madison County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Perry County, MO, Reynolds County, MO, Ripley County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Scott County, MO, Stoddard County, MO, Warren County, MO, Washington County, MO, Wayne County, MO, Alcorn County, MS, Benton County, MS, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Lafayette County, MS, Lee County, MS, Leflore County, MS, Marshall County, MS, Montgomery County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Yalobusha County, MS, Benton County, TN, Carroll County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dickson County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lake County, TN, Lauderdale County, TN, Lewis County, TN, Madison County, TN, McNairy County, TN, Montgomery County, TN, Obion County, TN, Perry County, TN, Shelby County, TN, Stewart County, TN, Tipton County, TN, Wayne County, TN, Weakley County, TN
The radar
The Memphis radar (KNQA), 71 km from the middle of the area, began a volume at 06:48 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
Little Rock, AR (KLZK), launched 00:00Z, 6.8 hours before the alert went out and 123 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
- 61 J/kg
- Mixed-layer CIN
- -316 J/kg
- Mixed-layer LCL
- 578 m above ground
- 0-6 km bulk shear
- 70 kt
- 0-1 km storm-relative helicity
- 335 m²/s²
- 0-3 km storm-relative helicity
- 421 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.2
The text
As transmitted, in the capitals the NWS used until 2016.
791
ACUS11 KWNS 290649
SWOMCD
SPC MCD 290649
TNZ000-KYZ000-INZ000-ALZ000-ILZ000-MSZ000-MOZ000-ARZ000-290745-
MESOSCALE DISCUSSION 0176
NWS STORM PREDICTION CENTER NORMAN OK
1249 AM CST WED FEB 29 2012
AREAS AFFECTED...SERN-EAST CENTRAL MO...CENTRAL AND ERN AR...SRN
IL...SWRN IND...WRN KY...WRN TN...AND NRN-NWRN MS
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 290649Z - 290745Z
NEW WW/S WILL BE NEEDED OVERNIGHT...WITH INITIAL TORNADO WATCH TO BE
COORDINATED SOON WITH WFOS FROM ERN MO...SRN IL...SWRN IND AND WRN
KY. POTENTIAL WATCH ISSUANCE FARTHER S WILL BE MONITORED FOR PARTS
OF CENTRAL/ERN AR TO WRN TN/NWRN MS.
ONGOING SEVERE WEATHER THREAT /PRODUCING DAMAGING WINDS AND A FEW
TORNADOES/ IS EXPECTED TO PERSIST OVERNIGHT INTO PARTS OF THE MID
AND LOWER MS VALLEY AND REACH THE LOWER OH/TN VALLEYS. THESE
THREATS ARE ATTENDANT TO A FAST MOVING /ENE AT 50+ KT/ QLCS WHICH AT
0630Z...REGIONAL RADAR IMAGERY SHOWED EXTENDING FROM SOUTH CENTRAL
MO /LACLEDE COUNTY/ INTO EAST CENTRAL OK /PITTSBURG COUNTY/. THE
SRN EXTENT OF THIS LINE WAS CHARACTERIZED BY MORE DISCRETE
STORMS...WHILE A FAST MOVING BOW ECHO PERSISTED ON THE NRN END
MOVING ENEWD THROUGH SRN MO.
AIR MASS DOWNSTREAM IS UNDERGOING DESTABILIZATION AS PW VALUES UP TO
1.5 INCH...NOW OVER ERN AR...SPREAD NNEWD CONTRIBUTING MUCAPE VALUES
OF 1000-1500 J/KG. 60-70 KT SWLY 850-700 MB WINDS WILL CONTINUE TO
SHIFT FROM THE ARKLATEX AND MID MS VALLEY INTO THE LOWER OH/TN
VALLEYS. THE CAPE/SHEAR PARAMETER SPACE WILL REMAIN MORE THAN
SUFFICIENT FOR ORGANIZED SEVERE STORMS DEVELOPING ENEWD OF ONGOING
ACTIVITY...WITH AN ATTENDANT THREAT FOR TORNADOES AND DAMAGING
WINDS.
..PETERS.. 02/29/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LMK...OHX...IND...HUN...PAH...ILX...MEG...JAN...
LSX...LZK...SGF...SHV...
LAT...LON 33069316 34729276 36639121 38789133 39048939 38688701
36658699 35098765 33428959 33069316SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 10:30 PM CST | Tornado Watch | SPC | Baxter, Benton, Boone, Carroll, Conway, Crawford and 20 more | 6 hr |
| Feb 28, 11:40 PM CST | Mesoscale Discussion | SPC | Benton | 95 min |
| Feb 29, 3:20 AM CST | Tornado Watch | SPC | Baxter, Clay, Cleburne, Conway, Craighead, Fulton and 20 more | 9 hr |
| Feb 29, 3:53 AM CST | Mesoscale Discussion | SPC | Baxter, Clay, Cleburne, Conway, Craighead, Faulkner and 20 more | 97 min |
| Feb 29, 8:07 AM CST | Mesoscale Discussion | SPC | Clay, Craighead, Greene, Independence, Jackson, Lawrence and 2 more | 53 min |
| Feb 29, 11:11 AM CST | Mesoscale Discussion | SPC | Crittenden, Mississippi | 2 hr |
| Feb 29, 11:46 AM CST | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 7 more | 89 min |
| Feb 29, 2:15 PM CST | Severe Thunderstorm Watch | SPC | Ashley, Chicot | 6 hr |
| Feb 29, 1:14 AM CST | Tornado Watch | SPC | Alexander, Bond, Clay, Clinton, Crawford, Edwards and 28 more | 11 hr |
| Feb 29, 2:40 AM CST | Mesoscale Discussion | SPC | Bartholomew, Brown, Clark, Crawford, Daviess, Dearborn and 22 more | 65 min |
| Feb 29, 4:39 AM CST | Tornado Watch | SPC | Clark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more | 7 hr |
| Feb 29, 7:38 AM CST | Mesoscale Discussion | SPC | Clark, Dearborn, Floyd, Harrison, Jefferson, Ohio and 1 more | 67 min |
| Feb 29, 11:41 AM CST | Mesoscale Discussion | SPC | Union | 3 hr |
| Feb 29, 7:27 AM CST | Tornado Watch | SPC | Boone, Bracken, Campbell, Carroll, Gallatin, Grant and 6 more | 5 hr |
| Feb 29, 11:31 AM CST | Tornado Watch | SPC | Adair, Allen, Barren, Bath, Bell, Boyle and 59 more | 8 hr |
| Feb 29, 12:24 PM CST | Mesoscale Discussion | SPC | Boyd, Greenup, Lawrence | 36 min |
| Feb 29, 12:37 PM CST | Tornado Watch | SPC | Boyd, Carter, Greenup, Lawrence, Lewis, Mason | 7 hr |
| Feb 29, 3:18 PM CST | Mesoscale Discussion | SPC | Boyd, Carter, Greenup, Lawrence, Lewis | 87 min |
| Feb 29, 3:34 PM CST | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bath, Bell, Boyle and 48 more | 116 min |
| Feb 29, 1:48 PM CST | Tornado Watch | SPC | Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more | 7 hr |
| Feb 28, 8:23 PM CST | Mesoscale Discussion | SPC | Atchison, Holt, Nodaway | 37 min |
| Feb 28, 9:47 PM CST | Mesoscale Discussion | SPC | Bates, Buchanan, Caldwell, Carroll, Cass, Clay and 9 more | 58 min |
| Feb 28, 10:07 PM CST | Severe Thunderstorm Watch | SPC | Bates, Caldwell, Carroll, Cass, Clay, Clinton and 9 more | 3 hr |
| Feb 29, 2:23 PM CST | Mesoscale Discussion | SPC | Johnson | 67 min |
| Feb 29, 4:36 PM CST | Mesoscale Discussion | SPC | Blount, Bradley, Carter, Cocke, Greene, Hamilton and 6 more | 54 min |
| Feb 29, 5:37 PM CST | Tornado Watch | SPC | Blount, Bradley, Carter, Cocke, Greene, Hamilton and 10 more | 3 hr |
Nearby
Mesoscale Discussions in Arkansas, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Tennessee, 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.