Alert archive / Nebraska / Mesoscale Discussions in 2004

Mesoscale Discussion 628

May 9, 200427 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 9, 2004, 9:43 PM CDT for 27 counties in Nebraska. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 9, 2004, 9:43 PM CDT (02:43 UTC)
Expired: May 9, 2004, 11:45 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 27 counties

Adams County, NE, Buffalo County, NE, Butler County, NE, Clay County, NE, Colfax County, NE, Cuming County, NE, Dawson County, NE, Fillmore County, NE, Franklin County, NE, Gosper County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Howard County, NE, Kearney County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Phelps County, NE, Platte County, NE, Polk County, NE, Seward County, NE, Sherman County, NE, Stanton County, NE, Wayne County, NE, Webster County, NE, York County, NE

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 2.7 hours before the alert went out and 164 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: 1885 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 1674 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 121 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 4.1

Open this sounding in Storm Lab

The text

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

488 
ACUS11 KWNS 100243
SWOMCD
SPC MCD 100243 
NEZ000-100445-

MESOSCALE DISCUSSION 0628
NWS STORM PREDICTION CENTER NORMAN OK
0943 PM CDT SUN MAY 09 2004

AREAS AFFECTED...CNTRL...SRN...ERN NEB

CONCERNING...SEVERE THUNDERSTORM WATCH 177...

VALID 100243Z - 100445Z

CONTINUE REMAINING VALID PORTION OF WW.

LARGE-SCALE FORCING ASSOCIATED WITH SHORT WAVE TROUGH MIGRATING OUT
OF THE NORTH CENTRAL ROCKIES INTO SOUTH DAKOTA/NEBRASKA CONTINUES TO
SUPPORT VIGOROUS CONVECTIVE DEVELOPMENT ACROSS A LARGE PART OF
CENTRAL INTO NORTHEASTERN NEBRASKA.  ACTIVITY HAS GENERALLY BEEN
FOCUSED ALONG LOW-LEVEL THERMAL RIDGE AND ASSOCIATED INSTABILITY
AXIS...WHICH IS BEGINNING TO BECOME OVERTURNED.  EXCEPTION TO THIS
APPEARS TO BE ACROSS THE IMPERIAL/MCCOOK AREAS...WHERE CAPPING
ELEVATED MIXED LAYER WILL PERSIST.  ON EDGE OF CAP ACROSS SOUTH
CENTRAL NEBRASKA...WHERE STEEP MID-LEVEL LAPSE RATES WILL CONTINUE
TO SUPPORT CAPE OF 1000 TO 2000 J/KG...FORCING ON NOSE OF 40 TO 50
KT SOUTHERLY LOW-LEVEL JET WILL MAINTAIN MOST INTENSE CONVECTION
INTO THE OVERNIGHT HOURS.  STRONG GUSTY WINDS MAY ACCOMPANY LEADING
EDGE OF OUTFLOW SURGING THROUGH THE GRAND ISLAND/KEARNEY AREAS
DURING THE NEXT HOUR OR TWO...WITH ADDITIONAL COLD POOL DEVELOPMENT
POSSIBLE THROUGH 06Z.

..KERR.. 05/10/2004

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

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

41189943 41409835 41869787 42339732 42399685 41869660
41089683 40489742 40149858 40129928 40369984 40840040

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 9, 7:55 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Antelope, Boone, Boyd, Buffalo, Cedar and 38 more	4 hr
May 9, 11:28 PM CDT	Mesoscale Discussion	SPC	Adams, Buffalo, Clay, Fillmore, Franklin, Hall and 6 more	62 min
May 10, 2:04 PM CDT	Mesoscale Discussion	SPC	Banner, Kimball, Scotts Bluff, Sioux	2 hr
May 10, 3:35 PM CDT	Severe Thunderstorm Watch	SPC	Scotts Bluff	5 hr

Nearby

Mesoscale Discussions in Nebraska, 2004 Every mesoscale discussion in 2004

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.