Alert archive / Oklahoma / Mesoscale Discussions in 2011
Mesoscale Discussion 810
The Storm Prediction Center issued this mesoscale discussion at May 19, 2011, 12:30 PM CDT for 18 counties in Oklahoma; 10 counties in Texas. It was in force for 30 min.
The area
The outline as issued.
The facts
- Issued
- May 19, 2011, 12:30 PM CDT (17:30 UTC)
- Expired
- May 19, 2011, 1:00 PM CDT
- In force
- 30 min
- Issued by
- the Storm Prediction Center
All 28 counties
Beckham County, OK, Blaine County, OK, Caddo County, OK, Comanche County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Greer County, OK, Harmon County, OK, Harper County, OK, Jackson County, OK, Kiowa County, OK, Major County, OK, Roger Mills County, OK, Tillman County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Archer County, TX, Baylor County, TX, Childress County, TX, Cottle County, TX, Foard County, TX, Hardeman County, TX, King County, TX, Knox County, TX, Wichita County, TX, Wilbarger County, TX
The radar
The Altus AFB radar (KFDR), 98 km from the middle of the area, began a volume at 17:34 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
Norman, OK (KOUN), launched 12:00Z, 5.5 hours before the alert went out and 193 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
- 1483 J/kg
- Mixed-layer CIN
- -94 J/kg
- Mixed-layer LCL
- 616 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 219 m²/s²
- 0-3 km storm-relative helicity
- 186 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 2.1
The text
As transmitted, in the capitals the NWS used until 2016.
603
ACUS11 KWNS 191730
SWOMCD
SPC MCD 191730
TXZ000-OKZ000-KSZ000-191800-
MESOSCALE DISCUSSION 0810
NWS STORM PREDICTION CENTER NORMAN OK
1230 PM CDT THU MAY 19 2011
AREAS AFFECTED...NWRN TX AND WRN OK
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 191730Z - 191800Z
A TORNADO WATCH WILL BE COORDINATED SOON FOR PARTS OF NWRN TX
THROUGH WRN OK.
EARLY AFTERNOON SURFACE ANALYSIS SHOWED AN AREA OF LOW PRESSURE OVER
WEST CENTRAL KS WITH A DRY LINE EXTENDING SWD ALONG AND INVOF THE
WRN OK/TX PANHANDLE BORDER AND THEN THROUGH CDS TO WEST CENTRAL TX.
ONGOING STRONG SURFACE HEATING ALONG AND WEST OF THE DRY LINE
COMBINED WITH AN ENHANCED AREA OF LOW LEVEL CONVERGENCE FROM KING TO
CHILDRESS COUNTIES TX ARE SUPPORTING DEEPER CU DEVELOPMENT.
OBJECTIVE ANALYSES INDICATED THE ENVIRONMENT ALONG THE DRY LINE NWD
INTO SOUTH CENTRAL KS IS UNCAPPED WITH MLCAPE OF 2000-3000 J/KG.
THIS COMBINED WITH STEEP LAPSE RATES AND EFFECTIVE BULK SHEAR OF
35-50 KT WILL SUPPORT SUPERCELLS. GIVEN EXPECTED BACKING OF
MID-UPPER LEVEL WINDS...STORM MOTION SHOULD BE TOWARD THE NNE WITH
TORNADOES BECOMING LIKELY AS CELLS MOVE INTO CORRIDOR OF GREATER LOW
LEVEL MOISTURE AND HIGHER VALUES OF EFFECTIVE SRH LOCATED ALONG AND
E OF THE DRY LINE.
..PETERS.. 05/19/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...DDC...LUB...AMA...
LAT...LON 33420043 34680020 35900021 37020018 37009949 36979837
35859830 33589841 33409917 33420043SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 19, 12:46 PM CDT | Tornado Watch | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 28 more | 9 hr |
| May 19, 3:44 PM CDT | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Comanche and 16 more | 61 min |
| May 19, 5:21 PM CDT | Mesoscale Discussion | SPC | Alfalfa, Blaine, Caddo, Canadian, Cleveland, Comanche and 18 more | 84 min |
Nearby
Mesoscale Discussions in Oklahoma, 2011Mesoscale Discussions in Texas, 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.