Alert archive / Nebraska / Mesoscale Discussions in 2011
Mesoscale Discussion 1925
The Storm Prediction Center issued this mesoscale discussion at Aug 9, 2011, 8:26 PM MDT for 4 states. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- Aug 9, 2011, 8:26 PM MDT (02:26 UTC)
- Expired
- Aug 9, 2011, 9:30 PM MDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
All 33 counties
Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Cheyenne County, KS, Decatur County, KS, Graham County, KS, Norton County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Arthur County, NE, Banner County, NE, Chase County, NE, Cheyenne County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Hayes County, NE, Hitchcock County, NE, Keith County, NE, Kimball County, NE, Lincoln County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE, Scotts Bluff County, NE, Laramie County, WY
The radar
The Cheyenne radar (KCYS), 178 km from the middle of the area, began a volume at 02:29 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
Denver, CO (KDNR), launched 00:00Z, 2.4 hours before the alert went out and 108 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 5160 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- -2 m²/s²
- 0-3 km storm-relative helicity
- 24 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
949
ACUS11 KWNS 100226
SWOMCD
SPC MCD 100226
KSZ000-NEZ000-COZ000-WYZ000-100330-
MESOSCALE DISCUSSION 1925
NWS STORM PREDICTION CENTER NORMAN OK
0926 PM CDT TUE AUG 09 2011
AREAS AFFECTED...PORTIONS SERN WY...SRN PANHANDLE OF NEB...SWRN
NEB...NWRN KS...NERN CO.
CONCERNING...TORNADO WATCH 754...
VALID 100226Z - 100330Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 754 CONTINUES.
SVR CONVECTION OVER SERN PORTIONS WW...BETWEEN HLC-MCK...WILL MOVE
SEWD INTO WW 759...BUT NOT ENTIRELY BEFORE EXPIRATION OF WW 759.
ISOLATED SVR TSTM ALSO IS MOVING SEWD OVER BANNER COUNTY NEB WITH
ADDITIONAL DEVELOPMENT OCCURRING FARTHER W IN SERN WY. ANOTHER WW
MAY BE REQUIRED OVER PORTIONS OF THIS AREA BEFORE SCHEDULED 03Z
EXPIRATION OF WW 754.
SFC MESOANALYSIS SHOWS STG OUTFLOW BOUNDARY EXTENDING WWD FROM
GROWING MCS NEAR RSL...ACROSS LANE COUNTY KS...THEN WNWWD NEAR ITR
AND NRN PORTIONS LINCOLN/DOUGLAS COUNTIES CO...MOVING SWD 10-15 KT
ACROSS ERN CO. SUBSTANTIAL ELY/UPSLOPE COMPONENT OF LOW-LEVEL WINDS
WILL PERSIST BEHIND THIS BOUNDARY OVER NERN CO. NRN PORTION OF
RELATED OUTFLOW POOL IS MORE ILL-DEFINED...BUT APPEARS TO BLEND WITH
AIR MASS ADVECTING SWWD TOWARD REGION BEHIND SYNOPTIC COLD FRONT
THAT IS ANALYZED OVER ERN KS. SVR TSTM MOVING SEWD FROM WY INTO WRN
NEB PANHANDLE MAY PRODUCE DAMAGING HAIL/GUSTS...BUT WILL MOVE INTO
AIR MASS CHARACTERIZED BY PROGRESSIVELY LOWER THETAE AND GREATER
MLCINH WITH TIME...RELATED BOTH TO CAA AND TO DIABATIC SFC COOLING.
THIS TREND INDICATES CONVECTION MAY WEAKEN...THOUGH TIMING IS
UNCERTAIN GIVEN EXISTENCE OF WELL-DEVELOPED/MATURE MESOCYCLONE AND
PROBABLY ROBUST STORM-SCALE COLD POOL TO FORCE ASCENT THROUGH
STABLE/NEAR-SFC LAYER FOR AT LEAST ANOTHER HOUR OR TWO. ADDITIONAL
DEVELOPMENT ALSO MAY OCCUR ATOP OUTFLOW POOL IN ZONE OF ELEVATED WAA
ACROSS NERN CO AND SWRN NEB.
..EDWARDS.. 08/10/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GID...LBF...GLD...BOU...CYS...
LAT...LON 41540507 41880443 41990330 41840160 41140063 40109988
39309980 39260182 39760380 40100477 41540507SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 8:51 PM MDT | Severe Thunderstorm Watch | SPC | Cheyenne, Kit Carson, Logan, Phillips, Sedgwick, Washington and 1 more | 7 hr |
| Aug 10, 3:42 PM MDT | Mesoscale Discussion | SPC | Logan, Phillips, Sedgwick | 63 min |
| Aug 10, 4:03 PM MDT | Severe Thunderstorm Watch | SPC | Logan, Phillips, Sedgwick, Washington | 6 hr |
| Aug 10, 5:54 PM MDT | Mesoscale Discussion | SPC | Cheyenne, Kit Carson, Logan, Phillips, Sedgwick, Washington and 1 more | 66 min |
| Aug 9, 7:27 PM MDT | Mesoscale Discussion | SPC | Clark, Comanche, Kiowa, Meade, Seward | 2 hr |
| Aug 9, 10:11 PM MDT | Mesoscale Discussion | SPC | Barber, Barton, Butler, Chautauqua, Cowley, Edwards and 28 more | 94 min |
| Aug 10, 2:25 AM MDT | Mesoscale Discussion | SPC | Barton, Butler, Cowley, Ellis, Ellsworth, Greenwood and 12 more | 65 min |
| Aug 10, 2:42 AM MDT | Severe Thunderstorm Watch | SPC | Barton, Butler, Chase, Chautauqua, Cowley, Elk and 17 more | 3 hr |
| Aug 10, 2:53 AM MDT | Mesoscale Discussion | SPC | Cheyenne, Decatur, Gove, Rawlins, Sheridan, Sherman and 1 more | 67 min |
Nearby
Mesoscale Discussions in Nebraska, 2011Mesoscale Discussions in Kansas, 2011Mesoscale Discussions in Colorado, 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.