Alert archive / Nebraska / Mesoscale Discussions in 2003

Mesoscale Discussion 959

May 13, 200317 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 13, 2003, 3:27 PM CDT for 17 counties in Nebraska. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
May 13, 2003, 3:27 PM CDT (20:27 UTC)
Expired
May 13, 2003, 5:00 PM CDT
In force
93 min
Issued by
the Storm Prediction Center

Counties Antelope County, NE, Boone County, NE, Colfax County, NE, Garfield County, NE, Greeley County, NE, Holt County, NE, Howard County, NE, Knox County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Sherman County, NE, Valley County, NE, Wheeler County, NE

The radar

The Omaha radar (KOAX), 161 km from the middle of the area, began a volume at 20:28 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, 8.5 hours before the alert went out and 229 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 2003-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 212 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 2003-05-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 93 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
212 J/kg
Mixed-layer CIN
-282 J/kg
Mixed-layer LCL
1567 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
212 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

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

555 
ACUS11 KWNS 132028
SWOMCD
SPC MCD 132027 
NEZ000-SDZ000-132200-

MESOSCALE DISCUSSION 0959
NWS STORM PREDICTION CENTER NORMAN OK
0327 PM CDT TUE MAY 13 2003

AREAS AFFECTED...EASTERN NEBRASKA

CONCERNING...SEVERE THUNDERSTORM WATCH 360...

VALID 132027Z - 132200Z

SEVERE STORMS TO MOVE NEWD AT 45 KT. 


STRONG FORCING ASSOCIATED WITH UPPER TROUGH IN WRN NEB SHOULD MOVE
BAND OF STRONG/SEVERE THUNDERSTORMS FROM 50 W OF YKN TO NEAR GRI
NEWD AT 40-45 KT. STORMS ARE EXPECTED TO GRADUALLY DEVELOP SWD AND A
FEW THUNDERSTORMS DEVELOPING ALONG A COLD FRONT...CURRENTLY LOCATED
FROM NEAR 55 E ANW TO 15 E LBF...MAY ALSO INTENSIFY AS THE STORMS 
MOVE INTO WW AREA.  MODERATE INSTABILITY AND DEEP LAYER SHEAR WOULD
SUPPORT SOME MID LEVEL ROTATION...BUT ENVIRONMENT APPEARS MORE
FAVORABLE FOR LARGE HAIL.

..IMY.. 05/13/2003

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

ATTN...WFO...FSD...OAX...GID...LBF...

41519902 42089905 42709910 42799836 42789791 42789756
42709747 42339726 41999722 41549705 41169737 40919803
40919893

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 13, 1:13 PM CDTMesoscale DiscussionSPCAdams, Antelope, Blaine, Boone, Brown, Buffalo and 45 more92 min
May 13, 1:45 PM CDTSevere Thunderstorm WatchSPCAdams, Antelope, Boone, Buffalo, Butler, Cedar and 38 more5 hr
May 13, 6:20 PM CDTSevere Thunderstorm WatchSPCAdams, Burt, Butler, Cass, Clay, Dodge and 22 more5 hr

Nearby

Mesoscale Discussions in Nebraska, 2003Every mesoscale discussion in 2003

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.