Alert archive / Nebraska / Mesoscale Discussions in 2008

Mesoscale Discussion 710

April 23, 20089 counties in Colorado; 11 counties in Kansas; 32 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2008, 6:06 PM MDT for 9 counties in Colorado; 11 counties in Kansas; 32 counties in Nebraska. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued: Apr 23, 2008, 6:06 PM MDT (00:06 UTC)
Expired: Apr 23, 2008, 8:00 PM MDT
In force: 114 min
Issued by: the Storm Prediction Center

All 52 counties

Baca County, CO, Cheyenne County, CO, Kiowa County, CO, Kit Carson County, CO, Logan County, CO, Phillips County, CO, Prowers County, CO, Sedgwick County, CO, Yuma County, CO, Cheyenne County, KS, Decatur County, KS, Gove County, KS, Greeley County, KS, Logan County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Wichita County, KS, Arthur County, NE, Blaine County, NE, Box Butte County, NE, Boyd County, NE, Brown County, NE, Chase County, NE, Cherry County, NE, Cheyenne County, NE, Custer County, NE, Dawes County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Garfield County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Holt County, NE, Hooker County, NE, Keith County, NE, Keya Paha County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE, Rock County, NE, Sheridan County, NE, Thomas County, NE

The radar

The North Platte radar (KLNX), 152 km from the middle of the area, began a volume at 00:08 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 00:00Z, 0.1 hours before the alert went out and 63 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 539 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 724 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 236 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 5.7

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 240006
SWOMCD
SPC MCD 240006 
NEZ000-SDZ000-KSZ000-COZ000-240200-

MESOSCALE DISCUSSION 0710
NWS STORM PREDICTION CENTER NORMAN OK
0706 PM CDT WED APR 23 2008

AREAS AFFECTED...WRN/CENTRAL NEB...ERN CO...NWRN KS

CONCERNING...TORNADO WATCH 220...223...

VALID 240006Z - 240200Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 220...223...CONTINUES.

SEVERAL SUPERCELLS ACROSS BOTH WW/S 220 AND 223 WILL CONTINUE TO
POSE A THREAT FOR LARGE HAIL/DMGG WINDS AND ISOLATED TORNADOES.
ATTM...THE GREATEST PROBABILITY OF TORNADOES APPEARS TO BE OVER THE
NRN 1/3 OF WW 220 AND OVER WW 223.

SFC ANALYSIS SHOWS STRONGLY BACKED LOW LEVEL FLOW OVER ALL OF WW/S
220 AND 223. OVER MUCH OF NWRN KS...ECENTRAL/SERN CO AND SWRN NEB
THIS BACKED LOW LEVEL FLOW WAS BEING ENHANCED BY STRONG OUTFLOW
GENERATED BY EARLIER CONVECTION OVER KS AND OK /RECENT WIND GUSTS
OVER 50 MPH AT GLD AND ITR/. MUCH COOLER TEMPERATURES WERE
ASSOCIATED WITH THIS OUTFLOW OVER KS AND FAR SWRN NEB. MODIFYING RUC
PFC SOUNDINGS INDICATES MUCH HIGHER MUCINH /OVER 100 J/KG/. THUS
CONVECTION OVER WRN KS/ERN CO IS EXPECTED TO STRUGGLE OVER THE NEXT
FEW HOURS...ALTHOUGH SHOULD CONTINUE TO SUPPORT AT LEAST A MARGINAL
SVR HAIL THREAT GIVEN STRONG LOW LEVEL MOIST INFLOW. GIVEN THE
ELEVATED NATURE OF THIS CONVECTION...THE TORNADO THREAT APPEARS TO
BE VERY LOW OVER WRN KS/ERN CO.

FURTHER NORTH...WHERE LOW LEVEL OUTFLOW HAS YET TO REACH...MODERATE
SELY LOW LEVEL INFLOW BENEATH STRENGTHENING MID LEVEL WINDS WILL
CONTINUE TO SUPPORT SUPERCELLS OVER THE NEB PANHANDLE AND ACROSS
NCENTRAL NEB /WW 223/. 0-1 KM SRH AROUND 250 J/KG WILL COMBINED WITH
MODERATE INSTABILITY TO CONTINUE TO SUPPORT A THREAT FOR ISOLATED
TORNADOES...ESPECIALLY WHERE SLOW/NEARLY STATIONARY STORM MOTIONS
LOCALLY ENHANCED SRH.

..CROSBIE.. 04/24/2008

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

ATTN...WFO...FSD...GID...LBF...DDC...UNR...GLD...PUB...BOU...CYS...

42910348 39770307 37100271 37040198 38280204 38340111
38690108 38710011 40990012 41129919 41759922 41809880
42199846 42889845 43109963 43040325

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 24, 6:52 AM MDT	Mesoscale Discussion	SPC	Chautauqua, Cherokee, Cowley, Crawford, Elk, Labette and 3 more	53 min
Apr 24, 4:33 PM MDT	Mesoscale Discussion	SPC	Cheyenne, Decatur, Graham, Norton, Phillips, Rawlins and 3 more	87 min
Apr 24, 5:02 PM MDT	Severe Thunderstorm Watch	SPC	Cheyenne, Decatur, Gove, Graham, Logan, Norton and 6 more	7 hr

Nearby

Mesoscale Discussions in Nebraska, 2008 Mesoscale Discussions in Kansas, 2008 Mesoscale Discussions in Colorado, 2008 Every mesoscale discussion in 2008

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.