Alert archive / Arkansas / Mesoscale Discussions in 2012
Mesoscale Discussion 549
The Storm Prediction Center issued this mesoscale discussion at Apr 15, 2012, 1:38 PM CDT for 24 counties in Arkansas; 15 counties in Missouri. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Apr 15, 2012, 1:38 PM CDT (18:38 UTC)
- Expired
- Apr 15, 2012, 3:15 PM CDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
All 39 counties
Baxter County, AR, Boone County, AR, Carroll County, AR, Conway County, AR, Crawford County, AR, Franklin County, AR, Fulton County, AR, Garland County, AR, Johnson County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Montgomery County, AR, Newton County, AR, Perry County, AR, Polk County, AR, Pope County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Stone County, AR, Van Buren County, AR, Washington County, AR, Yell County, AR, Christian County, MO, Crawford County, MO, Dent County, MO, Douglas County, MO, Howell County, MO, Laclede County, MO, Ozark County, MO, Phelps County, MO, Pulaski County, MO, Shannon County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Webster County, MO, Wright County, MO
The radar
The Springfield radar (KSGF), 137 km from the middle of the area, began a volume at 18:41 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
Springfield, MO (KSGF), launched 12:00Z, 6.6 hours before the alert went out and 116 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
- 31 J/kg
- Mixed-layer CIN
- -142 J/kg
- Mixed-layer LCL
- 855 m above ground
- 0-6 km bulk shear
- 55 kt
- 0-1 km storm-relative helicity
- 319 m²/s²
- 0-3 km storm-relative helicity
- 381 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
286
ACUS11 KWNS 151838
SWOMCD
SPC MCD 151838
MOZ000-ARZ000-OKZ000-152015-
MESOSCALE DISCUSSION 0549
NWS STORM PREDICTION CENTER NORMAN OK
0138 PM CDT SUN APR 15 2012
AREAS AFFECTED...WRN AR THROUGH SRN AND CNTRL MO
CONCERNING...TORNADO WATCH 177...
VALID 151838Z - 152015Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 177 CONTINUES.
THREAT FOR ISOLATED TORNADOES...DAMAGING WIND AND HAIL WILL REMAIN
POSSIBLE WITH LINE OF STORMS FROM NWRN AR THROUGH SRN MO THIS
AFTERNOON. PRIMARY THREAT WITH STORMS DEVELOPING IN WAKE OF THE LINE
ACROSS SWRN THROUGH CNTRL MO APPEARS TO BE HAIL...BUT ISOLATED
DAMAGING WIND GUSTS ARE ALSO POSSIBLE.
LLJ WILL REMAIN IN PLACE OVER THE LOWER MS VALLEY THIS AFTERNOON
AHEAD OF PROGRESSIVE UPPER TROUGH MAINTAINING LARGE HODOGRAPHS IN
WARM SECTOR. LINE OF STORMS FROM SWRN MO THROUGH WRN AR WILL MOVE
EWD THROUGH THIS REGION. LATEST OBJECTIVE ANALYSIS SHOWS AXIS OF
MLCAPE FROM BELOW 500 J/KG OVER SRN MO TO NEAR 1000 J/KG OVER NWRN
AND CNTRL AR. STORMS SHOULD INTENSIFY AND BECOME BETTER ORGANIZED AS
THE BOUNDARY LAYER GRADUALLY BUT SLOWLY WARMS. GIVEN THE FAVORABLE
KINEMATIC ENVIRONMENT...OCCASIONAL SUPERCELL AND BOWING STRUCTURES
WILL REMAIN LIKELY WITH A THREAT OF ISOLATED TORNADOES AND DAMAGING
WIND.
OTHER STORMS HAVE BEEN INCREASING IN WAKE OF INITIAL LINE OVER SWRN
THROUGH CNTRL MO AND MOVING RAPIDLY NNEWD AT AROUND 75 KT. THESE
STORMS APPEAR TO BE DEVELOPING WITHIN ZONE OF DEEPER ASCENT NEAR JET
ENTRANCE REGION AND VORT LOBE ROUNDING BASE OF UPPER TROUGH
OVERTAKING THE WRN EDGE OF THE MOIST AXIS. RAPID MOVEMENT OF THESE
STORMS SUGGESTS THEY ARE AT LEAST SLIGHTLY ELEVATED ABOVE THE
OUTFLOW FROM THE LEADING CONVECTION...BUT ARE EMBEDDED WITHIN STRONG
DEEP LAYER WINDS AND UNIDIRECTIONAL EFFECTIVE SHEAR.
..DIAL.. 04/15/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PAH...LSX...LZK...SGF...SHV...TSA...
LAT...LON 34319453 35999423 37959271 38239107 37139117 34279335
34319453SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 15, 6:35 AM CDT | Mesoscale Discussion | SPC | Benton, Crawford, Madison, Sebastian, Washington | 85 min |
| Apr 15, 6:38 AM CDT | Severe Thunderstorm Watch | SPC | Benton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more | 4 hr |
| Apr 15, 9:25 AM CDT | Mesoscale Discussion | SPC | Baxter, Boone, Carroll, Conway, Crawford, Franklin and 22 more | 95 min |
| Apr 15, 10:51 AM CDT | Tornado Watch | SPC | Baxter, Boone, Carroll, Conway, Crawford, Franklin and 18 more | 7 hr |
| Apr 15, 3:44 PM CDT | Mesoscale Discussion | SPC | Calhoun, Clark, Columbia, Hempstead, Lafayette, Miller and 3 more | 91 min |
| Apr 15, 4:22 PM CDT | Mesoscale Discussion | SPC | Arkansas, Bradley, Calhoun, Clay, Cleburne, Cleveland and 29 more | 83 min |
| Apr 15, 4:25 PM CDT | Tornado Watch | SPC | Arkansas, Baxter, Bradley, Calhoun, Clark, Clay and 49 more | 6 hr |
| Apr 14, 11:28 PM CDT | Mesoscale Discussion | SPC | Putnam | 92 min |
| Apr 14, 11:48 PM CDT | Mesoscale Discussion | SPC | Clay, Platte | 87 min |
| Apr 15, 1:37 AM CDT | Tornado Watch | SPC | Andrew, Atchison, Buchanan, DeKalb, Gentry, Holt and 2 more | 5 hr |
| Apr 15, 4:32 AM CDT | Mesoscale Discussion | SPC | Bates, Buchanan, Caldwell, Cass, Clay, Clinton and 6 more | 88 min |
| Apr 15, 4:42 PM CDT | Tornado Watch | SPC | Audrain, Boone, Butler, Callaway, Carter, Cole and 35 more | 6 hr |
Nearby
Mesoscale Discussions in Arkansas, 2012Mesoscale Discussions in Missouri, 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.