Alert archive / Nebraska / Mesoscale Discussions in 2012

Mesoscale Discussion 2053

October 13, 20124 states

The Storm Prediction Center issued this mesoscale discussion at Oct 13, 2012, 7:04 PM CDT for 4 states. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued
Oct 13, 2012, 7:04 PM CDT (00:04 UTC)
Expired
Oct 13, 2012, 8:00 PM CDT
In force
56 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 27 counties

Adams County, IA, Fremont County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Pottawattamie County, IA, Taylor County, IA, Brown County, KS, Andrew County, MO, Atchison County, MO, Holt County, MO, Nodaway County, MO, Worth County, MO, Cass County, NE, Douglas County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE

The radar

The Omaha radar (KOAX), 90 km from the middle of the area, began a volume at 00:04 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, 0.1 hours before the alert went out and 90 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, Omaha, NE at 00:00Z on 2012-10-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1014 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, Omaha, NE at 00:00Z on 2012-10-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.1939587897Sfc1 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
1014 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
795 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
14 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

789 
ACUS11 KWNS 140004
SWOMCD
SPC MCD 140004 
IAZ000-MOZ000-KSZ000-NEZ000-140100-

MESOSCALE DISCUSSION 2053
NWS STORM PREDICTION CENTER NORMAN OK
0704 PM CDT SAT OCT 13 2012

AREAS AFFECTED...SERN NEB...SWRN IA...FAR NWRN MO...FAR NERN KS

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 140004Z - 140100Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...THE POTENTIAL FOR ISOLATED DMGG WIND GUSTS MAY ACCOMPANY
TSTMS APPROACHING FROM N-CNTRL KS...BUT THE ENVIRONMENT APPEARS LESS
FAVORABLE FOR WIDESPREAD STRONG-SVR WINDS. THEREFORE...THE POTENTIAL
FOR A WW IS NOT PARTICULARLY HIGH...BUT CONVECTIVE TRENDS WILL
CONTINUE TO BE MONITORED.

DISCUSSION...CONVECTION ACROSS N-CNTRL KS IS EXPECTED TO CONTINUE
DEVELOPING NEWD INTO PARTS OF SERN NEB AND NERN KS...AND MAY
EVENTUALLY AFFECT PORTIONS OF FAR SWRN IA AND NWRN MO. THIS AREA IS
POSITIONED ALONG THE NRN FRINGE OF THE RICHEST LOW-LEVEL
MOISTURE...ALTHOUGH SFC DEW POINTS IN THE MID-60S ARE YIELDING
ESTIMATED MLCAPE VALUES OF 1000-1500 J/KG. ADDITIONALLY...18Z
NAM/22Z RUC FORECAST MODEL SOUNDINGS SUGGEST LOW-LEVEL WIND FLOW IS
COMPARATIVELY WEAKER THAN AREAS FARTHER S...BUT THE PRESENCE OF
DRIER MIDLEVEL AIR COULD SUPPORT DOWNDRAFTS CAPABLE OF PRODUCING
STRONG-SVR WIND GUSTS. CURRENT THINKING IS THAT THE THREAT FOR DMGG
WIND GUSTS MAY REMAIN TOO MARGINAL/ISOLATED TO WARRANT ISSUANCE OF A
NEW WW...BUT CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED.

..ROGERS/HART.. 10/14/2012

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

ATTN...WFO...DMX...EAX...OAX...TOP...

LAT...LON   41159468 40489437 40069454 39749532 39829602 40009666
            40129712 40479728 40889723 41279673 41419606 41419533
            41159468

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 13, 9:37 PM CDTMesoscale DiscussionSPCBarry, Christian, Dade, Dallas, Douglas, Greene and 11 more113 min
Oct 13, 10:15 PM CDTSevere Thunderstorm WatchSPCHowell, Oregon, Ozark, Shannon, Texas6 hr

Nearby

Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Missouri, 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.