Alert archive / Nebraska / Mesoscale Discussions in 2003

Mesoscale Discussion 2137

August 9, 2003Sedgwick County, Colorado; 14 counties in Nebraska; Tripp County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 9, 2003, 6:04 PM MDT for Sedgwick County, Colorado; 14 counties in Nebraska; Tripp County, South Dakota. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued: Aug 9, 2003, 6:04 PM MDT (00:04 UTC)
Expired: Aug 9, 2003, 8:00 PM MDT
In force: 116 min
Issued by: the Storm Prediction Center

Counties Sedgwick County, CO, Arthur County, NE, Blaine County, NE, Brown County, NE, Cherry County, NE, Deuel County, NE, Garden County, NE, Grant County, NE, Hooker County, NE, Keith County, NE, Keya Paha County, NE, Logan County, NE, McPherson County, NE, Sheridan County, NE, Thomas County, NE, Tripp County, SD

The radar

The North Platte radar (KLNX), 76 km from the middle of the area, began a volume at 00:06 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 0.1 hours before the alert went out and 128 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: 1605 J/kg
Mixed-layer CIN: -19 J/kg
Mixed-layer LCL: 2294 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

279 
ACUS11 KWNS 100005
SWOMCD
SPC MCD 100004 
SDZ000-NEZ000-COZ000-100200-

MESOSCALE DISCUSSION 2137
NWS STORM PREDICTION CENTER NORMAN OK
0704 PM CDT SAT AUG 09 2003

AREAS AFFECTED...WRN/CNTRL NEB...EXTREME NERN CO

CONCERNING...SEVERE THUNDERSTORM WATCH 854...

VALID 100004Z - 100200Z

THE THREAT OF SEVERE THUNDERSTORMS CONTINUES FOR ALL WW 854.

RADAR REFLECTIVITY INDICATES CLUSTER OF STRONG/SEVERE MULTICELLULAR
CONVECTION IS MOVING SEWD THROUGH CENTRAL NEBRASKA AT 15 MPH. MLCAPE
VALUES OVER THE CNTRL PART OF THE STATE HAVE REACHED ABOUT 2500 J/KG
WITH DEEP LAYER SHEAR AROUND 25 TO 30 KTS.  THESE ENVIRONMENTAL
PARAMETERS SUGGEST THE CLUSTER OF STORMS WILL CONTINUE TO MOVE
SEWD...WITH THE POTENTIAL FOR LARGE HAIL AND SEVERE WIND.

FARTHER TO THE NORTH/WEST...TEMPERATURES HAVE CLIMBED INTO THE LOWER
 90S WITH SURFACE DEW POINTS HOLDING AROUND 55 TO 60.  MESOANALYSIS
SHOWS SFC LOW CENTER IS LOCATED OVER BOX BUTTE COUNTY...WITH AN AREA
OF STRONG SURFACE CONVERGENCE EXTENDING EASTWARD TOWARD NCNTRL
NEBRASKA.  GIVEN THE STRONG SURFACE CONVERGENCE AND ENVIRONMENTAL
PARAMETERS /MLCAPE 2000 J/KG...0-6 KM SHEAR 30 KTS/...SEVERE
THUNDERSTORM DEVELOPMENT REMAINS POSSIBLE OVER WRN NEBRASKA AND
EXTREME NERN COLORADO.

..BRIGHT.. 08/10/2003

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

ATTN...WFO...FSD...LBF...UNR...BOU...CYS...

42400278 43509953 41589951 40500279

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 9, 6:56 PM MDT	Mesoscale Discussion	SPC	Antelope, Boone, Boyd, Cedar, Garfield, Greeley and 9 more	2 hr

Nearby

Mesoscale Discussions in Nebraska, 2003 Mesoscale Discussions in Colorado, 2003 Mesoscale Discussions in South Dakota, 2003 Every mesoscale discussion in 2003

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.