Alert archive / Oklahoma / Mesoscale Discussions in 2011

Mesoscale Discussion 997

May 27, 201110 counties in Oklahoma; 4 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 27, 2011, 3:22 PM CDT for 10 counties in Oklahoma; 4 counties in Texas. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued: May 27, 2011, 3:22 PM CDT (20:22 UTC)
Expired: May 27, 2011, 5:15 PM CDT
In force: 113 min
Issued by: the Storm Prediction Center

Counties Carter County, OK, Comanche County, OK, Cotton County, OK, Garvin County, OK, Grady County, OK, Jefferson County, OK, Love County, OK, McClain County, OK, Murray County, OK, Stephens County, OK, Clay County, TX, Cooke County, TX, Jack County, TX, Montague County, TX

The radar

The Altus AFB radar (KFDR), 106 km from the middle of the area, began a volume at 20:23 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, 8.4 hours before the alert went out and 111 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1015 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 390 m²/s²
0-3 km storm-relative helicity: 842 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

375 
ACUS11 KWNS 272023
SWOMCD
SPC MCD 272022
OKZ000-TXZ000-272215-

MESOSCALE DISCUSSION 0997
NWS STORM PREDICTION CENTER NORMAN OK
0322 PM CDT FRI MAY 27 2011

AREAS AFFECTED...PTNS SCNTRL OK...NCNTRL TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 272022Z - 272215Z

THIS AREA IS BEING MONITORED FOR POSSIBLE THUNDERSTORM DEVELOPMENT
IN THE NEXT SEVERAL HOURS.  WEAK SFC LOW JUST E OF CDS WILL MOVE
ONLY SLOWLY EASTWARD THE NEXT SEVERAL HOURS.  SATELLITE/RADAR AND
SURFACE OBS INDICATED ONE DRYLINE FROM THE LOW ARCS THROUGH
SOUTHWEST OK AND THEN SOUTHWARD INTO NW/NCNTRL TX.  A SECONDARY
DRYLINE NOTED IN CLEAR AIR RADAR DATA IS MOVING THROUGH THE SRN TX
PNHDL AND WILL BE INTERSECTING THE EASTERN DRYLINE BOUNDARY ADDING
ADDITIONAL FORCING ABOUT THE TIME OF MAXIMUM HEATING...2200 TO 0000
UTC.

MOIST UNSTABLE AIR WITH MLCAPES OF 3500 J/KG AND WEAK CAPPING
INVERSION JUST AHEAD OF DRYLINE AND INCREASED FORCING NEXT SEVERAL
HOURS ALONG WITH PEAK HEATING MAY ALLOW A STRONG STORM OR TWO TO
DEVELOP.  IF STORMS MANAGE TO DEVELOP...A WATCH MAY BE NEEDED WITH
THE RISK OF LARGE HAIL AND BRIEF STRONG WINDS.

..BOTHWELL.. 05/27/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FWD...OUN...

LAT...LON   33189853 34069851 34369853 34879887 35069861 35079841
            35079824 35069789 35109764 35139748 35099725 34929706
            34679692 34409690 34109699 33709715 33459730 33319754
            33159778 33069828 33189853

Nearby

Mesoscale Discussions in Oklahoma, 2011 Mesoscale Discussions in Texas, 2011 Every 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.