Alert archive / Missouri / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 90
The Storm Prediction Center issued this severe thunderstorm watch at Mar 19, 2012, 10:35 PM CDT for 5 counties in Arkansas; 18 counties in Missouri. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 19, 2012, 10:35 PM CDT (03:35 UTC)
- Expired
- Mar 20, 2012, 2:00 AM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 23 counties
Baxter County, AR, Boone County, AR, Marion County, AR, Newton County, AR, Searcy County, AR, Barry County, MO, Christian County, MO, Dallas County, MO, Dent County, MO, Douglas County, MO, Greene County, MO, Howell County, MO, Laclede County, MO, Maries 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), 78 km from the middle of the area, began a volume at 03:35 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 20, 12:09 AM CDT | Severe Thunderstorm Warning | SGF | Christian, Douglas, Greene, Webster | 41 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Springfield, MO (KSGF), launched 00:00Z, 3.6 hours before the alert went out and 77 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
- 173 J/kg
- Mixed-layer CIN
- -17 J/kg
- Mixed-layer LCL
- 1207 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 221 m²/s²
- 0-3 km storm-relative helicity
- 369 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 3.0
The text
As transmitted, in the capitals the NWS used until 2016.
649
WWUS20 KWNS 200332
SEL0
SPC WW 200332
ARZ000-MOZ000-201000-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 90
NWS STORM PREDICTION CENTER NORMAN OK
1035 PM CDT MON MAR 19 2012
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
NORTH CENTRAL ARKANSAS
SOUTHERN MISSOURI
EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 1035 PM
UNTIL 500 AM CDT.
HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 40
STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES SOUTH
SOUTHWEST OF HARRISON ARKANSAS TO 5 MILES NORTH NORTHEAST OF FORT
LEONARD WOOD MISSOURI. FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.
OTHER WATCH INFORMATION...CONTINUE...WW 87...WW 88...WW 89...
DISCUSSION...BOWING SQUALL LINE OVER NORTHWEST AR WILL TRACK
NORTHEASTWARD INTO SOUTHERN MO DURING THE NEXT FEW HOURS. STORMS
ARE IN A REGION OF ONLY MARGINAL INSTABILITY...BUT VERY STRONG
ENVIRONMENTAL WIND FIELDS AND PRESENCE OF LOW LEVEL BOUNDARY WILL
PROMOTE A RISK OF DAMAGING WINDS AND HAIL IN THE STRONGEST CELLS.
THE POTENTIAL FOR QLCS TORNADOES IS ALSO NON-ZERO.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.
A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM MOTION
VECTOR 23035.
...HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 19, 7:28 PM CDT | Tornado Watch | SPC | Howard, Little River, Miller, Sevier | 9 hr |
| Mar 19, 8:48 PM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Crawford, Madison, Sebastian, Washington | 57 min |
| Mar 19, 10:17 PM CDT | Mesoscale Discussion | SPC | Baxter, Boone, Marion, Newton, Pope, Searcy | 58 min |
| Mar 20, 1:48 PM CDT | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Calhoun, Cleburne, Cleveland and 22 more | 117 min |
| Mar 20, 2:55 PM CDT | Tornado Watch | SPC | Arkansas, Baxter, Bradley, Calhoun, Cleburne, Cleveland and 25 more | 7 hr |
| Mar 20, 5:57 PM CDT | Mesoscale Discussion | SPC | Arkansas, Fulton, Independence, Izard, Jackson, Monroe and 4 more | 93 min |
Nearby
Severe Thunderstorm Watches in Missouri, 2012Severe Thunderstorm Watches in Arkansas, 2012Every severe thunderstorm watch 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.