Alert archive / Iowa / Mesoscale Discussions in 2009

Mesoscale Discussion 588

April 26, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2009, 6:14 PM CDT for 4 states. It was in force for 61 min.

The area

The outline as issued.

The facts

Issued
Apr 26, 2009, 6:14 PM CDT (23:14 UTC)
Expired
Apr 26, 2009, 7:15 PM CDT
In force
61 min
Issued by
the Storm Prediction Center
All 97 counties

Adams County, IA, Appanoose County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cedar County, IA, Chickasaw County, IA, Clarke County, IA, Clayton County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Grundy County, IA, Hardin County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Van Buren County, IA, Wapello County, IA, Warren County, IA, Washington County, IA, Wayne County, IA, Anderson County, KS, Atchison County, KS, Brown County, KS, Chase County, KS, Coffey County, KS, Doniphan County, KS, Douglas County, KS, Franklin County, KS, Harvey County, KS, Jackson County, KS, Jefferson County, KS, Johnson County, KS, Leavenworth County, KS, Linn County, KS, Lyon County, KS, Marion County, KS, Miami County, KS, Morris County, KS, Osage County, KS, Shawnee County, KS, Wabaunsee County, KS, Wyandotte County, KS, Adair County, MO, Andrew County, MO, Buchanan County, MO, Caldwell County, MO, Carroll County, MO, Cass County, MO, Clay County, MO, Clinton County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Jackson County, MO, Lafayette County, MO, Linn County, MO, Livingston County, MO, Mercer County, MO, Nodaway County, MO, Platte County, MO, Putnam County, MO, Ray County, MO, Schuyler County, MO, Sullivan County, MO, Worth County, MO, Grant County, WI, Iowa County, WI, Lafayette County, WI

The radar

The Pleasant Hill radar (KEAX), 145 km from the middle of the area, began a volume at 23:13 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

Topeka, KS (KTOP), launched 12:00Z, 11.2 hours before the alert went out and 165 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, Topeka, KS at 12:00Z on 2009-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Topeka, KS at 12:00Z on 2009-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 200 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2039 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
200 m²/s²
0-3 km storm-relative helicity
301 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 7:17 PM CDTMesoscale DiscussionSPCAppanoose, Davis, Wapello, Wayne58 min
Apr 25, 9:23 PM CDTMesoscale DiscussionSPCDavis, Des Moines, Henry, Lee, Van Buren67 min
Apr 25, 10:09 PM CDTSevere Thunderstorm WatchSPCFremont, Page6 hr
Apr 26, 9:18 AM CDTMesoscale DiscussionSPCAudubon, Crawford, Harrison, Mills, Monona, Pottawattamie and 2 more27 min
Apr 26, 9:34 AM CDTSevere Thunderstorm WatchSPCAudubon, Buena Vista, Calhoun, Carroll, Cass, Cherokee and 29 more6 hr
Apr 26, 12:30 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Cass, Dallas and 13 more60 min
Apr 26, 12:48 PM CDTTornado WatchSPCAdair, Adams, Audubon, Boone, Butler, Calhoun and 33 more4 hr
Apr 26, 2:41 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 35 more3 hr
Apr 26, 5:02 PM CDTTornado WatchSPCAdair, Adams, Allamakee, Appanoose, Benton, Black Hawk and 41 more6 hr
Apr 26, 5:14 PM CDTMesoscale DiscussionSPCClayton, Delaware, Dubuque, Jackson61 min
Apr 25, 9:58 PM CDTMesoscale DiscussionSPCAllen, Anderson, Butler, Chase, Chautauqua, Clay and 40 more92 min
Apr 25, 10:39 PM CDTTornado WatchSPCAllen, Chautauqua, Cowley, Elk, Harper, Labette and 5 more4 hr
Apr 26, 1:28 AM CDTMesoscale DiscussionSPCAllen, Barber, Chautauqua, Cowley, Elk, Greenwood and 7 more92 min
Apr 26, 2:10 AM CDTMesoscale DiscussionSPCAnderson, Atchison, Brown, Clay, Coffey, Dickinson and 20 more95 min
Apr 26, 2:39 AM CDTTornado WatchSPCAllen, Chautauqua, Cowley, Elk, Harper, Labette and 5 more3 hr
Apr 26, 5:47 AM CDTMesoscale DiscussionSPCBarton, Dickinson, Edwards, Ellsworth, Ford, Lincoln and 8 more58 min
Apr 26, 5:58 AM CDTTornado WatchSPCBarton, Chase, Clark, Clay, Comanche, Dickinson and 24 more7 hr
Apr 26, 10:19 AM CDTMesoscale DiscussionSPCBarber, Butler, Comanche, Cowley, Dickinson, Ellsworth and 14 more56 min
Apr 26, 10:54 AM CDTMesoscale DiscussionSPCAtchison, Barber, Barton, Butler, Chase, Chautauqua and 42 more66 min
Apr 26, 11:07 AM CDTTornado Watch PDSSPCBarber, Barton, Brown, Butler, Chase, Clark and 40 more7 hr
Apr 26, 12:27 PM CDTMesoscale DiscussionSPCBarton, Clark, Clay, Cloud, Edwards, Ellsworth and 12 more2 hr
Apr 26, 5:44 PM CDTMesoscale DiscussionSPCBarber, Butler, Cowley, Harper, Harvey, Kingman and 5 more61 min
Apr 26, 6:16 PM CDTTornado Watch PDSSPCAllen, Barber, Butler, Chase, Chautauqua, Comanche and 16 more8 hr
Apr 26, 2:00 PM CDTMesoscale DiscussionSPCDane, Green, Jefferson, Lafayette, Rock, Walworth and 1 more60 min

Nearby

Mesoscale Discussions in Iowa, 2009Mesoscale Discussions in Missouri, 2009Mesoscale Discussions in Kansas, 2009Every mesoscale discussion in 2009

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.