Alert archive / Nebraska / Mesoscale Discussions in 2016
Mesoscale Discussion 1439
The Storm Prediction Center issued this mesoscale discussion at Jul 29, 2016, 3:00 PM MDT for 7 counties in Nebraska; 5 counties in South Dakota; 6 counties in Wyoming. It was in force for 90 min.
The area
The outline as issued.
The facts
- Issued
- Jul 29, 2016, 3:00 PM MDT (21:00 UTC)
- Expired
- Jul 29, 2016, 4:30 PM MDT
- In force
- 90 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
Counties Banner County, NE, Box Butte County, NE, Dawes County, NE, Morrill County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Custer County, SD, Fall River County, SD, Lawrence County, SD, Oglala Lakota County, SD, Pennington County, SD, Campbell County, WY, Converse County, WY, Crook County, WY, Goshen County, WY, Niobrara County, WY, Weston County, WY
The radar
The Rapid City radar (KUDX), 121 km from the middle of the area, began a volume at 21:02 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
Rapid City, SD (KRAP), launched 12:00Z, 9.0 hours before the alert went out and 114 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
- 46 J/kg
- Mixed-layer CIN
- -73 J/kg
- Mixed-layer LCL
- 833 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
817
ACUS11 KWNS 292101
SWOMCD
SPC MCD 292100
NEZ000-SDZ000-WYZ000-292230-
MESOSCALE DISCUSSION 1439
NWS STORM PREDICTION CENTER NORMAN OK
0400 PM CDT FRI JUL 29 2016
AREAS AFFECTED...ERN WY...SW SD...NEB PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 292100Z - 292230Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...LARGE HAIL AND DAMAGING WIND GUSTS ARE POSSIBLE WITH THE
ONGOING TSTMS ACROSS THE REGION. ADDITIONAL DEVELOPMENT IS ALSO
POSSIBLE FARTHER W IN ERN WY. TRENDS WILL BE MONITORED CLOSELY AND A
WW MAY BE NEEDED ACROSS THE REGION.
DISCUSSION...TSTM COVERAGE CONTINUES TO INCREASE WITHIN THE MODEST
INSTABILITY AND THE NWLY FLOW ACROSS THE REGION. PRIMARY IMPETUS FOR
CONVECTIVE DEVELOPMENT APPEARS TO BE SUBTLE LARGE FORCING FOR ASCENT
ASSOCIATED WITH A PERTURBATION MOVING INTO WY WITH SECONDARY SUPPORT
PROVIDED BY THE UPSLOPE FLOW INTO THE REGION. ENVIRONMENT HERE IS
CHARACTERIZED BY MODEST INSTABILITY -- MLCAPE AROUND 1000 J/KG --
AND AMPLE VERTICAL SHEAR -- EFFECTIVE BULK SHEAR NEAR 40 KT. SOME
HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE WITH THE STRONGEST
STORMS. ADDITIONALLY...GIVEN THE LIKELIHOOD OF STRONG COLD
POOLS...SOME UPSCALE GROWTH IS POSSIBLE. A WW MAY BE NEEDED ACROSS
THE REGION TO COVER THE POTENTIAL SVR THREAT.
..MOSIER/KERR.. 07/29/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LBF...UNR...CYS...RIW...
LAT...LON 44570549 44670388 44030259 42360126 41180329 43100643
44570549SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 12:34 PM MDT | Mesoscale Discussion | SPC | Kimball | 116 min |
| Jul 29, 3:27 PM MDT | Severe Thunderstorm Watch | SPC | Banner, Box Butte, Cheyenne, Dawes, Deuel, Garden and 5 more | 5 hr |
| Jul 29, 5:27 PM MDT | Mesoscale Discussion | SPC | Banner, Box Butte, Cheyenne, Dawes, Deuel, Garden and 6 more | 108 min |
| Jul 29, 1:08 PM MDT | Severe Thunderstorm Watch | SPC | Albany, Goshen, Laramie, Platte | 9 hr |
Nearby
Mesoscale Discussions in Nebraska, 2016Mesoscale Discussions in Wyoming, 2016Mesoscale Discussions in South Dakota, 2016Every mesoscale discussion in 2016
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.