Alert archive / Arkansas / Mesoscale Discussions in 2012
Mesoscale Discussion 665
The Storm Prediction Center issued this mesoscale discussion at May 2, 2012, 6:08 PM CDT for 16 counties in Arkansas; Benton County, Tippah County, Mississippi; 8 counties in Tennessee. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- May 2, 2012, 6:08 PM CDT (23:08 UTC)
- Expired
- May 2, 2012, 7:45 PM CDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 5%
All 26 counties
Arkansas County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Desha County, AR, Drew County, AR, Jackson County, AR, Lee County, AR, Lincoln County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, St. Francis County, AR, Woodruff County, AR, Benton County, MS, Tippah County, MS, Crockett County, TN, Fayette County, TN, Hardeman County, TN, Haywood County, TN, Lauderdale County, TN, Madison County, TN, Shelby County, TN, Tipton County, TN
The radar
The Memphis radar (KNQA), 81 km from the middle of the area, began a volume at 23:10 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
Little Rock, AR (KLZK), launched 12:00Z, 11.1 hours before the alert went out and 49 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
- 696 J/kg
- Mixed-layer CIN
- -170 J/kg
- Mixed-layer LCL
- 1175 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -136 m²/s²
- 0-3 km storm-relative helicity
- -76 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
958
ACUS11 KWNS 022309
SWOMCD
SPC MCD 022308
MSZ000-TNZ000-MOZ000-ARZ000-030045-
MESOSCALE DISCUSSION 0665
NWS STORM PREDICTION CENTER NORMAN OK
0608 PM CDT WED MAY 02 2012
AREAS AFFECTED...ERN AR AND PARTS OF SWRN-WRN TN
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 022308Z - 030045Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...TSTMS WILL CONTINUE TO MOVE W/NWWD INTO ERN AR...WHILE
ADDITIONAL STORMS TRACK NWWD FROM NRN MS INTO SWRN TN EARLY THIS
EVENING. IN ADDITION TO SOME THREAT FOR ISOLATED STRONGER WIND
GUSTS ACROSS ERN AR AND WRN TN...ISOLATED HAIL /GENERALLY AROUND 1
INCH IN DIAMETER/...WILL BE POSSIBLE WITH THE STRONGEST STORMS.
DISCUSSION...AT 23Z...REGIONAL RADAR IMAGERY INDICATED A W/NWWD
MOVING OUTFLOW BOUNDARY EXTENDING SSW-NNE OVER FAR ERN AR TO CROSS
COUNTY AR AND THEN EWD THROUGH FAR SWRN TN. THE AIR MASS
IMMEDIATELY DOWNSTREAM TO THE W-N REMAINS MODERATELY UNSTABLE WITH
OBJECTIVE ANALYSES SHOWING STEEP LOW AND MIDLEVEL LAPSE RATES. DEEP
LAYER SHEAR IS VERY WEAK AND WILL CONTINUE TO BE THE MAIN LIMITING
FACTOR FOR A MORE ORGANIZED SEVERE WEATHER THREAT AS ACTIVITY
SPREADS WWD THROUGH ERN A AND NWWD INTO WRN TN. VERY WARM SURFACE
TEMPERATURES HAVE RESULTED IN STEEP LOW LEVEL LAPSE RATES WHICH MAY
ENHANCE A THREAT FOR STRONG WIND GUSTS. WHILE THE WEAK SHEAR WILL
LIMIT STORM ORGANIZATION...PROMOTING PULSE STORMS...THE AVAILABILITY
FOR FAVORABLE INSTABILITY ENHANCING UPDRAFTS WILL BEGIN TO WANE BY
01Z RESULTING IN A SHORT TERM THREAT...ALSO PRECLUDING THE NEED FOR
A WW.
..PETERS/THOMPSON.. 05/02/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MEG...JAN...LZK...
LAT...LON 34459182 35149161 35919108 36069019 35998934 35688876
34998864 34698880 34858965 34899006 34969039 34379087
33549131 33559167 33689186 34459182SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 2, 2:43 PM CDT | Mesoscale Discussion | SPC | George, Jackson, Stone | 62 min |
Nearby
Mesoscale Discussions in Arkansas, 2012Mesoscale Discussions in Tennessee, 2012Mesoscale Discussions in Mississippi, 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.