Alert archive / Nebraska / Mesoscale Discussions in 2014

Mesoscale Discussion 792

June 3, 201421 counties in Nebraska; 8 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jun 3, 2014, 12:07 PM CDT for 21 counties in Nebraska; 8 counties in South Dakota. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued
Jun 3, 2014, 12:07 PM CDT (17:07 UTC)
Expired
Jun 3, 2014, 1:30 PM CDT
In force
83 min
Issued by
the Storm Prediction Center
All 29 counties

Antelope County, NE, Blaine County, NE, Boone County, NE, Boyd County, NE, Brown County, NE, Cedar County, NE, Dixon County, NE, Garfield County, NE, Greeley County, NE, Holt County, NE, Keya Paha County, NE, Knox County, NE, Loup County, NE, Madison County, NE, Pierce County, NE, Platte County, NE, Rock County, NE, Stanton County, NE, Valley County, NE, Wayne County, NE, Wheeler County, NE, Bon Homme County, SD, Charles Mix County, SD, Clay County, SD, Douglas County, SD, Gregory County, SD, Hutchinson County, SD, Tripp County, SD, Yankton County, SD

The radar

The North Platte radar (KLNX), 163 km from the middle of the area, began a volume at 17:08 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, 5.1 hours before the alert went out and 222 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 2014-06-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1655 joules per kilogram.LCLLFCEL10008507005003002001001 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 2014-06-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 square meters per square second.19395878Sfc1 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
1655 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
898 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
280 m²/s²
Significant tornado parameter
1.2
Supercell composite
5.6

Open this sounding in Storm Lab

The text

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

188 
ACUS11 KWNS 031707
SWOMCD
SPC MCD 031707 
NEZ000-SDZ000-031830-

MESOSCALE DISCUSSION 0792
NWS STORM PREDICTION CENTER NORMAN OK
1207 PM CDT TUE JUN 03 2014

AREAS AFFECTED...PARTS OF SRN SOUTH DAKOTA INTO N CNTRL/NERN NEB

CONCERNING...SEVERE THUNDERSTORM WATCH 206...

VALID 031707Z - 031830Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 206
CONTINUES.

SUMMARY...SEVERE THREAT CONTINUES WITH ONE OR MORE GROWING AND
CONSOLIDATING CONVECTIVE CLUSTERS EXPECTED BY LATE AFTERNOON. 
SUPERCELLS ARE POSSIBLE AS THIS OCCURS...WITH THE RISK FOR SEVERE
HAIL/STRONG WIND GUSTS AND TORNADOES INCREASING THROUGH 20-22Z.  AT
LEAST PORTIONS OF THE WATCH AND AREAS TO THE SOUTH/EAST ARE BEING
MONITORED FOR A TORNADO WATCH.

DISCUSSION...INTENSE CONVECTION NOW EAST OF VALENTINE HAS TAKEN A
SOUTHEASTWARD TURN DURING THE PAST HOUR OR SO.  THIS LIKELY IS
FOCUSED WITHIN A ZONE OF ENHANCED WARM ADVECTION /ROUGHLY DELINEATED
BY THE 700 MB THERMAL GRADIENT/ WHICH MAY SUPPORT SOUTHEASTWARD
DEVELOPMENT INTO AREA NORTH THROUGH WEST OF NORFOLK THROUGH 19-21Z. 
AT THE SAME TIME...WITH CONTINUED BOUNDARY LAYER HEATING AND MIXING
ACROSS WEST CENTRAL NEBRASKA...STRENGTHENING LOWER LEVEL WARM
ADVECTION AND CONVERGENCE ON THE NOSE OF A 30 KT SOUTHERLY 850 MB
JET SEEMS LIKELY TO SUPPORT ADDITIONAL INTENSE STORM DEVELOPMENT
ACROSS NORTH CENTRAL NEBRASKA...NEAR/SOUTH THROUGH SOUTHEAST OF
VALENTINE.

IN THE PRESENCE OF STEEP MID-LEVEL LAPSE RATES...AND MODERATELY
LARGE BOUNDARY-LAYER BASED CAPE...SUPERCELLS ARE LIKELY WITH
ACTIVITY GRADUALLY CONGEALING/CONSOLIDATING WITH DOWNSTREAM ACTIVITY
INTO A GROWING CONVECTIVE CLUSTER.  THE RISK FOR TORNADOES IS
EXPECTED TO INCREASE TOWARD 20-22Z...IN ADDITION TO A CONTINUING
RISK FOR SEVERE HAIL...AND POTENTIALLY DAMAGING WIND GUSTS.

..KERR.. 06/03/2014

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

ATTN...WFO...FSD...OAX...ABR...GID...LBF...UNR...

LAT...LON   43699945 43389772 43059687 42159680 41599708 41399831
            41569909 42190064 42750113 43450046 43699945

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 3, 3:02 AM CDTMesoscale DiscussionSPCBlaine, Brown, Cherry, Grant, Hooker, Keya Paha and 6 more118 min
Jun 3, 7:00 AM CDTMesoscale DiscussionSPCBlaine, Brown, Garfield, Greeley, Holt, Howard and 6 more2 hr
Jun 3, 9:36 AM CDTSevere Thunderstorm WatchSPCBoyd, Brown, Cherry, Holt, Keya Paha, Rock and 2 more7 hr
Jun 3, 1:12 PM CDTTornado WatchSPCAdams, Antelope, Blaine, Boone, Brown, Buffalo and 55 more10 hr
Jun 3, 1:20 PM CDTMesoscale DiscussionSPCArthur, Banner, Box Butte, Cheyenne, Dawes, Deuel and 7 more85 min
Jun 3, 2:37 PM CDTSevere Thunderstorm WatchSPCDawes, Sioux6 hr
Jun 3, 3:11 PM CDTTornado WatchSPCArthur, Box Butte, Cherry, Deuel, Garden, Grant and 10 more7 hr
Jun 3, 3:48 PM CDTMesoscale DiscussionSPCAntelope, Boone, Burt, Butler, Colfax, Cuming and 18 more87 min
Jun 3, 4:37 PM CDTMesoscale DiscussionSPCCass, Douglas, Nemaha, Sarpy, Washington83 min
Jun 3, 4:54 PM CDTMesoscale DiscussionSPCAdams, Blaine, Boone, Buffalo, Butler, Clay and 36 more96 min
Jun 3, 5:59 PM CDTTornado WatchSPCAdams, Blaine, Boone, Buffalo, Butler, Cass and 43 more7 hr
Jun 3, 6:40 PM CDTMesoscale DiscussionSPCDawes, Sioux65 min
Jun 3, 1:51 PM CDTMesoscale DiscussionSPCButte, Harding114 min

Nearby

Mesoscale Discussions in Nebraska, 2014Mesoscale Discussions in South Dakota, 2014Every mesoscale discussion in 2014

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.