Alert archive / Nebraska / Mesoscale Discussions in 2012

Mesoscale Discussion 526

April 14, 2012Decatur County, Rawlins County, Kansas; 15 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2012, 1:41 PM CDT for Decatur County, Rawlins County, Kansas; 15 counties in Nebraska. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 14, 2012, 1:41 PM CDT (18:41 UTC)
Expired
Apr 14, 2012, 3:45 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center

Counties Decatur County, KS, Rawlins County, KS, Arthur County, NE, Custer County, NE, Dawson County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Perkins County, NE, Red Willow County, NE

The radar

The North Platte radar (KLNX), 150 km from the middle of the area, began a volume at 18:42 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 6.7 hours before the alert went out and 63 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-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2012-04-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 2012-04-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 192 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
1610 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
192 m²/s²
0-3 km storm-relative helicity
202 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.

143 
ACUS11 KWNS 141841
SWOMCD
SPC MCD 141841 
NEZ000-KSZ000-COZ000-142045-

MESOSCALE DISCUSSION 0526
NWS STORM PREDICTION CENTER NORMAN OK
0141 PM CDT SAT APR 14 2012

AREAS AFFECTED...SWRN NEB THROUGH NWRN KS

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 141841Z - 142045Z

STORMS ARE EXPECTED TO DEVELOP FROM SWRN NEB THROUGH NWRN KS BY MID
TO LATE THIS AFTERNOON. SUPERCELLS WITH TORNADOES AND VERY LARGE
HAIL ARE EXPECTED TO BE THE MAIN THREATS. TORNADO WATCH WILL BE
NEEDED BEFORE 20Z.

THIS AFTERNOON A WARM FRONT EXTENDS THROUGH SRN NEB INTO SWRN NEB
WHERE IT INTERSECTS A DRYLINE THAT ARCS SEWD THROUGH THE NERN TIP OF
CO THEN SWD THROUGH WRN KS. LOW CLOUDS ARE DECREASING FROM THE SOUTH
AS BOUNDARY LAYER MIXING DEVELOPS NWD. THIS IS CONTRIBUTING TO
DESTABILIZATION IN WARM SECTOR. LATEST OBJECTIVE ANALYSIS SHOWS AN
AXIS OF 500-1000 J/KG MLCAPE FROM SWRN NEB INTO NWRN KS...AND
INSTABILITY WILL INCREASE FURTHER AS DIABATIC WARMING CONTINUES.
BANDS OF HIGH LEVEL CIRRUS HAVE BEEN INCREASING ACROSS NERN CO INTO
WRN NEB...AND THIS MAY BE INDICATIVE OF AGEOSTROPHIC FORCING WITHIN
UPPER JET EXIT REGION THAT WILL BEGIN TO OVERTAKE THE DRYLINE THIS
AFTERNOON. LATEST VISIBLE IMAGERY SHOWS AN AREA OF CUMULUS
INCREASING IN VICINITY OF THE DRYLINE OVER WCNTRL KS. AS THE CAP
WEAKENS AND THE BOUNDARY LAYER CONTINUES TO DESTABILIZE...STORMS ARE
EXPECTED TO INITIATE FROM NWRN KS THROUGH SWRN NEB. EFFECTIVE DEEP
SHEAR OF 50+ KT WILL SUPPORT SUPERCELLS WITH VERY LARGE HAIL AND
TORNADOES LIKELY.

..DIAL.. 04/14/2012

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

ATTN...WFO...GID...LBF...GLD...BOU...CYS...

LAT...LON   39180089 39500107 40510161 41230227 41570271 41900236
            41950096 41539947 41169938 40669997 39400035 39180089

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 13, 9:14 PM CDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Butler, Chase, Chautauqua and 17 more61 min
Apr 14, 3:42 AM CDTTornado WatchSPCChautauqua, Labette, Montgomery5 hr
Apr 14, 7:11 AM CDTMesoscale DiscussionSPCCherokee, Labette64 min
Apr 14, 9:42 AM CDTMesoscale DiscussionSPCClark, Finney, Ford, Gove, Grant, Gray and 10 more93 min
Apr 14, 10:43 AM CDTTornado Watch PDSSPCBarber, Barton, Clark, Clay, Cloud, Comanche and 42 more7 hr
Apr 14, 11:44 AM CDTMesoscale DiscussionSPCBarber, Barton, Clark, Clay, Cloud, Comanche and 40 more61 min
Apr 14, 12:11 PM CDTMesoscale DiscussionSPCButler, Chase, Chautauqua, Coffey, Cowley, Dickinson and 19 more64 min
Apr 14, 1:44 PM CDTMesoscale DiscussionSPCBarton, Clark, Cloud, Edwards, Ellis, Ellsworth and 20 more61 min
Apr 14, 2:28 PM CDTMesoscale DiscussionSPCClay, Cloud, Jewell, Lincoln, Mitchell, Ottawa and 2 more32 min
Apr 14, 3:01 PM CDTMesoscale DiscussionSPCBarber, Barton, Clark, Comanche, Edwards, Ellsworth and 10 more29 min
Apr 14, 3:48 PM CDTMesoscale DiscussionSPCBarber, Barton, Clark, Clay, Cloud, Comanche and 33 more57 min
Apr 14, 4:47 PM CDTMesoscale DiscussionSPCAtchison, Brown, Doniphan, Nemaha58 min
Apr 14, 4:54 PM CDTMesoscale DiscussionSPCBarber, Barton, Clay, Cloud, Comanche, Dickinson and 32 more66 min
Apr 14, 5:00 PM CDTTornado WatchSPCDoniphan7 hr
Apr 14, 5:24 PM CDTTornado Watch PDSSPCBarber, Barton, Brown, Butler, Chase, Chautauqua and 57 more9 hr
Apr 14, 11:27 AM CDTMesoscale DiscussionSPCAdams, Buffalo, Clay, Fillmore, Franklin, Furnas and 19 more2 hr
Apr 14, 12:00 PM CDTTornado Watch PDSSPCAdams, Antelope, Boone, Buffalo, Burt, Butler and 46 more7 hr
Apr 14, 2:15 PM CDTMesoscale DiscussionSPCAdams, Burt, Butler, Cass, Clay, Colfax and 22 more90 min
Apr 14, 2:33 PM CDTTornado WatchSPCBlaine, Custer, Frontier, Garfield, Hayes, Holt and 7 more8 hr
Apr 14, 6:27 PM CDTTornado Watch PDSSPCAdams, Buffalo, Cass, Clay, Dawson, Fillmore and 30 more9 hr
Apr 14, 6:57 PM CDTMesoscale DiscussionSPCAdams, Buffalo, Butler, Cass, Clay, Douglas and 26 more63 min

Nearby

Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Kansas, 2012Every mesoscale discussion in 2012

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.