Alert archive / Oklahoma / Mesoscale Discussions in 2011
Mesoscale Discussion 1739
The Storm Prediction Center issued this mesoscale discussion at Jul 25, 2011, 5:29 PM CDT for 20 counties in Oklahoma; 11 counties in Texas. It was in force for 91 min.
The area
The outline as issued.
The facts
- Issued
- Jul 25, 2011, 5:29 PM CDT (22:29 UTC)
- Expired
- Jul 25, 2011, 7:00 PM CDT
- In force
- 91 min
- Issued by
- the Storm Prediction Center
All 31 counties
Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Dewey County, OK, Garvin County, OK, Grady County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Jefferson County, OK, Kiowa County, OK, McClain County, OK, Roger Mills County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Armstrong County, TX, Briscoe County, TX, Castro County, TX, Childress County, TX, Collingsworth County, TX, Donley County, TX, Hall County, TX, Hardeman County, TX, Randall County, TX, Swisher County, TX, Wheeler County, TX
The radar
The Altus AFB radar (KFDR), 95 km from the middle of the area, began a volume at 22:28 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
Norman, OK (KOUN), launched 12:00Z, 10.5 hours before the alert went out and 195 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
- 550 J/kg
- Mixed-layer CIN
- -190 J/kg
- Mixed-layer LCL
- 1836 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 41 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
418
ACUS11 KWNS 252229
SWOMCD
SPC MCD 252229
OKZ000-TXZ000-260000-
MESOSCALE DISCUSSION 1739
NWS STORM PREDICTION CENTER NORMAN OK
0529 PM CDT MON JUL 25 2011
AREAS AFFECTED...CNTRL/SWRN OK...PORTIONS OF THE TX PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 252229Z - 260000Z
ISOLATED STORMS COULD PRODUCE WET MICROBURSTS CAPABLE OF DMGG WIND
GUSTS. THE ISOLATED NATURE OF ANY SVR THREAT WILL PRECLUDE THE NEED
FOR A WW.
LATE AFTERNOON SFC MESOANALYSIS PLACES A 1007-MB LOW NEAR FORT SILL.
A COMPOSITE FRONT / OUTFLOW BOUNDARY LIES E-W ACROSS SRN PORTIONS OF
THE TX PANHANDLE INTO SWRN OK NEAR THE SFC LOW AND ARCS ESEWD TOWARD
THE RED RIVER OVER S-CNTRL OK AND N-CNTRL TX. NORTH OF THE
BOUNDARY...SUFFICIENT HEATING AMIDST A RESERVOIR OF MODEST LOW-LEVEL
MOISTURE IS SUPPORTING MLCAPE VALUES OF 1000 TO 1500 J/KG.
CONVERGENCE NEAR THE BOUNDARY...LOCALLY ENHANCED NEAR THE SFC
LOW...WILL CONTINUE TO SUPPORT ISOLATED TO SCATTERED CONVECTION INTO
THE LATE AFTERNOON HOURS. THE GREATEST CONCENTRATION OF THIS
ACTIVITY WILL BE WEST OF THE SFC LOW...WHERE THE UNDERCUTTING NATURE
OF THE BOUNDARY COULD AID IN UNSTABLE PARCELS BEING LIFTED TO THEIR
LFC/S. OUTSIDE OF ONGOING CONVECTION...SFC TEMPERATURES FROM 95 TO
105 DEGREES SUPPORTING STEEP LOW-LEVEL LAPSE RATES AND DCAPE VALUES
OF 1000-1300 J/KG MAY PROMOTE WET MICROBURSTS CAPABLE OF DMGG WIND
GUSTS. WITH VERY MODEST WLY FLOW OF 15 TO 20 KT OBSERVED IN THE
2-3.5-KM-AGL LAYER PER TWIN LAKES OK VWP DATA...SOME CONVECTION
COULD BE STEERED TOWARD PORTIONS OF THE INTERSTATE 35 CORRIDOR.
HOWEVER...WITH WEAK VERTICAL SHEAR IN PLACE...CONVECTIVE IS FORECAST
TO EXHIBIT A PULSE MODE...WITH THE SVR THREAT VERY ISOLATED. AFTER
01Z...A WEAKENING TREND IS ANTICIPATED IN RESPONSE TO NOCTURNAL
COOLING.
..COHEN.. 07/25/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...LUB...AMA...
LAT...LON 35970011 36159950 36119890 35869823 35309745 34939725
34369733 34089762 34109810 34209951 34230144 34440252
35010231 35270160 35350063 35970011Nearby
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.