Alert archive / Nebraska / Mesoscale Discussions in 2016
Mesoscale Discussion 1549
The Storm Prediction Center issued this mesoscale discussion at Aug 16, 2016, 7:32 PM CDT for 5 counties in Iowa; 34 counties in Nebraska; 8 counties in South Dakota. It was in force for 58 min.
The area
The outline as issued.
The facts
- Issued
- Aug 16, 2016, 7:32 PM CDT (00:32 UTC)
- Expired
- Aug 16, 2016, 8:30 PM CDT
- In force
- 58 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 5%
All 47 counties
Harrison County, IA, Monona County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Antelope County, NE, Boone County, NE, Burt County, NE, Butler County, NE, Cass County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Douglas County, NE, Greeley County, NE, Hamilton County, NE, Johnson County, NE, Knox County, NE, Lancaster County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Otoe County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE, Wheeler County, NE, York County, NE, Bon Homme County, SD, Clay County, SD, Hutchinson County, SD, Lincoln County, SD, Minnehaha County, SD, Turner County, SD, Union County, SD, Yankton County, SD
The radar
The Omaha radar (KOAX), 76 km from the middle of the area, began a volume at 00:35 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
Omaha, NE (KOAX), launched 00:00Z, 0.5 hours before the alert went out and 76 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
- 2247 J/kg
- Mixed-layer CIN
- -17 J/kg
- Mixed-layer LCL
- 1291 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 218 m²/s²
- Significant tornado parameter
- 1.1
- Supercell composite
- 10.5
The text
As transmitted.
449
ACUS11 KWNS 170032
SWOMCD
SPC MCD 170032
IAZ000-NEZ000-SDZ000-170130-
MESOSCALE DISCUSSION 1549
NWS STORM PREDICTION CENTER NORMAN OK
0732 PM CDT TUE AUG 16 2016
AREAS AFFECTED...EASTERN NEBRASKA...FAR SOUTHEASTERN SOUTH
DAKOTA...FAR WESTERN IOWA
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 170032Z - 170130Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...ISOLATED SEVERE STORMS SHOULD CONTINUE ACROSS THE
DISCUSSION AREA THROUGH SUNSET....WITH A WEAKENING TREND EXPECTED
SHORTLY THEREAFTER. WW NOT ANTICIPATED.
DISCUSSION...ISOLATED LEFT-MOVING AND RIGHT-MOVING STORMS HAVE
DEVELOPED IN FAR NORTHEASTERN NEBRASKA AND FAR SOUTHEASTERN SOUTH
DAKOTA OVER THE LAST COUPLE OF HOURS...WITH ADDITIONAL ISOLATED
ACTIVITY SOUTH OF OAX. THESE STORMS ARE IN A RELATIVELY WEAKLY
SHEARED...YET MODERATELY TO STRONGLY UNSTABLE ENVIRONMENT...WITH
PRIMARILY OUTFLOW-DOMINANT STORMS.
A LACK OF LOW-LEVEL JET INTENSIFICATION...ALONG WITH RELATIVELY WEAK
FORCING ALOFT FOR ASCENT SUGGESTS THAT STORMS SHOULD WEAKEN
SUBSTANTIALLY AFTER DARK WITH THE ONSET OF NOCTURNAL BOUNDARY LAYER
COOLING. THIS...ALONG WITH THE ISOLATED NATURE OF THE STORMS AS
CURRENTLY OBSERVED...SHOULD PRECLUDE THE NEED FOR A WW ISSUANCE.
..COOK/GRAMS.. 08/17/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...DMX...FSD...OAX...GID...LBF...
LAT...LON 41659550 42109553 42809583 43439645 43699674 43569756
42999829 42489874 41919884 41389856 40909807 40529746
40349681 40369620 40719588 41259567 41659550Nearby
Mesoscale Discussions in Nebraska, 2016Mesoscale Discussions in South Dakota, 2016Mesoscale Discussions in Iowa, 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.