Alert archive / Arkansas / Mesoscale Discussions in 2011
Mesoscale Discussion 1249
The Storm Prediction Center issued this mesoscale discussion at Jun 16, 2011, 3:41 PM CDT for 29 counties in Arkansas. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- Jun 16, 2011, 3:41 PM CDT (20:41 UTC)
- Expired
- Jun 16, 2011, 4:45 PM CDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
All 29 counties
Arkansas County, AR, Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Jefferson County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Montgomery County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Phillips County, AR, Pike County, AR, Polk County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Yell County, AR
The radar
The Little Rock radar (KLZK), 65 km from the middle of the area, began a volume at 20:42 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
Shreveport, LA (KSHV), launched 12:00Z, 8.7 hours before the alert went out and 234 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
- 3144 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 966 m above ground
- 0-6 km bulk shear
- 8 kt
- 0-1 km storm-relative helicity
- -68 m²/s²
- 0-3 km storm-relative helicity
- -58 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
242
ACUS11 KWNS 162041
SWOMCD
SPC MCD 162041
ARZ000-MSZ000-162145-
MESOSCALE DISCUSSION 1249
NWS STORM PREDICTION CENTER NORMAN OK
0341 PM CDT THU JUN 16 2011
AREAS AFFECTED...CNTRL/SRN AR
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 162041Z - 162145Z
UNCERTAINTY EXISTS IN THE FORECAST EVOLUTION OF CONVECTION THIS
AFTERNOON/EVENING...THOUGH SHOULD MORE ORGANIZATION OF CURRENT
STORMS OCCUR...A WW MAY BECOME NECESSARY. DMGG WINDS AND HAIL WILL
BE THE PRIMARY THREATS.
A REMNANT AND NEARLY STATIONARY MCV MAY FINALLY BEGIN TO PROGRESS
ESEWD AHEAD OF A MORE PRONOUNCED UPPER WAVE ON 2030Z WV IMAGERY OVER
SWRN MO/NERN OK. THIS MAY PROVIDE FORCING FOR ASCENT LATER THIS
AFTERNOON/EVENING...WITH CONVECTION CONTINUING TO DEVELOP ALONG AN
OUTFLOW BOUNDARY ACROSS SERN AR...AND ANY ADDITIONAL OUTFLOW
BOUNDARIES THAT MAY DEVELOP. MEANWHILE...A WARM FRONT ACROSS CNTRL
AR COULD PROVIDE FOCUS FOR ADDITIONAL DEVELOPMENT. HOWEVER...THE CU
FIELD ON VISIBLE SATELLITE IMAGERY WOULD SUGGEST SUBSIDENCE NORTH OF
THE WARM FRONT...WHILE SURFACE WIND FIELDS SHOW VIRTUALLY NO
CONFLUENCE TO THE SOUTH. THEREFORE...FOCUS FOR MORE ORGANIZED
CONVECTION IS MUDDLED AT THE MOMENT...AND WOULD LIKELY RELY ON THE
DEVELOPMENT OF A COLD POOL FROM THE SERN AR CONVECTION. SHOULD MORE
ORGANIZATION OCCUR...STEEP MID LEVEL LAPSE RATES OBSERVED ON THE 18Z
LITTLE ROCK SOUNDING /NEAR 8 C/KM /...AND STEEPENING LOW LEVEL LAPSE
RATES IN THE PRESENCE OF STRONG SURFACE HEATING WILL BE FAVORABLE
FOR PULSE SEVERE AND MULTICELLULAR CLUSTERS CAPABLE OF DMGG WINDS
AND HAIL.
..HURLBUT.. 06/16/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MEG...JAN...LZK...SHV...
LAT...LON 34819067 33359113 33189217 33519359 34369440 34919389
35199282 34819067SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 16, 12:26 PM CDT | Severe Thunderstorm Watch | SPC | Benton, Carroll, Crawford, Franklin, Madison, Washington | 7 hr |
| Jun 16, 4:41 PM CDT | Severe Thunderstorm Watch | SPC | Arkansas, Clark, Clay, Cleveland, Craighead, Crittenden and 24 more | 7 hr |
| Jun 16, 5:17 PM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more | 58 min |
| Jun 16, 6:18 PM CDT | Mesoscale Discussion | SPC | Arkansas, Crittenden, Cross, Desha, Lee, Lincoln and 5 more | 87 min |
Nearby
Mesoscale Discussions in Arkansas, 2011Every mesoscale discussion in 2011
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.