Alert archive / Nebraska / Mesoscale Discussions in 2012
Mesoscale Discussion 1504
The Storm Prediction Center issued this mesoscale discussion at Jul 19, 2012, 4:42 PM MDT for 14 counties in Nebraska; 7 counties in South Dakota. It was in force for 63 min.
The area
The outline as issued.
The facts
- Issued
- Jul 19, 2012, 4:42 PM MDT (22:42 UTC)
- Expired
- Jul 19, 2012, 5:45 PM MDT
- In force
- 63 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 21 counties
Arthur County, NE, Blaine County, NE, Boyd County, NE, Brown County, NE, Cherry County, NE, Grant County, NE, Hooker County, NE, Keith County, NE, Keya Paha County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Rock County, NE, Thomas County, NE, Brule County, SD, Charles Mix County, SD, Gregory County, SD, Lyman County, SD, Mellette County, SD, Todd County, SD, Tripp County, SD
The radar
The North Platte radar (KLNX), 81 km from the middle of the area, began a volume at 22:45 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
N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 10.7 hours before the alert went out and 168 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
- 331 J/kg
- Mixed-layer CIN
- -426 J/kg
- Mixed-layer LCL
- 2075 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- -32 m²/s²
- 0-3 km storm-relative helicity
- 39 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
The text
As transmitted, in the capitals the NWS used until 2016.
252
ACUS11 KWNS 192242
SWOMCD
SPC MCD 192242
SDZ000-NEZ000-192345-
MESOSCALE DISCUSSION 1504
NWS STORM PREDICTION CENTER NORMAN OK
0542 PM CDT THU JUL 19 2012
AREAS AFFECTED...SRN NEB...NRN KS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 192242Z - 192345Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...AN ISOLATED SEVERE THREAT MAY BE DEVELOPING ACROSS SCNTRL
SD AND WRN NEB EARLY THIS EVENING. SEVERE WIND GUSTS AND HAIL WILL
BE POSSIBLE WITH THE STRONGER CORES. WW ISSUANCE REMAINS POSSIBLE
ESPECIALLY IF THE CELLS CAN CONTINUE TO INCREASE IN INTENSITY OVER
THE NEXT 1 TO 2 HOURS.
DISCUSSION...A CLUSTER OF STRONG THUNDERSTORMS HAS DEVELOPED
SOUTHWEST OF PIERRE SD ALONG THE NRN EDGE OF MODERATE INSTABILITY
WHERE MLCAPE VALUES ARE ESTIMATED IN THE 1000 TO 1500 J/KG RANGE. IN
ADDITION...THE WSR-88D VWP AT VALENTINE NEB SHOWS 40 KT OF 0-6 KM
SHEAR SUGGESTING THE STORMS COULD DEVELOP A SEVERE THREAT THAT COULD
PERSIST IF THE LINE CAN ORGANIZE FURTHER. DUE TO THE VERY HOT SFC
TEMPS ABOVE 100 F ALONG WITH DEWPOINTS IN THE MID 50S
F...TEMPS/DEWPOINT SPREADS ARE VERY LARGE SUGGESTING OUTFLOW GUSTS
COULD BECOME SEVERE. HAIL MAY ALSO OCCUR BUT MAY BE THE LESSER OF
THE TWO THREATS DUE TO THE WARM TEMPS ALOFT AND HOT BOUNDARY LAYER
CONDITIONS.
..BROYLES/CARBIN.. 07/19/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FSD...ABR...LBF...UNR...
LAT...LON 40950082 41889954 42429910 42979865 43409845 43909890
44129971 44020051 42520196 41280221 40950082SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 12:56 PM MDT | Mesoscale Discussion | SPC | Grant, Marshall, Roberts | 64 min |
Nearby
Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in South Dakota, 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.