Alert archive / Iowa / Mesoscale Discussions in 2005
Mesoscale Discussion 539
The Storm Prediction Center issued this mesoscale discussion at Apr 10, 2005, 2:57 PM CDT for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 10, 2005, 2:57 PM CDT (19:57 UTC)
- Expired
- Apr 10, 2005, 5:00 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 93 counties
Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Buena Vista County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Cherokee County, IA, Chickasaw County, IA, Clarke County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Decatur County, IA, Dickinson County, IA, Emmet County, IA, Floyd County, IA, Franklin County, IA, Fremont County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Harrison County, IA, Howard County, IA, Humboldt County, IA, Ida County, IA, Jasper County, IA, Kossuth County, IA, Lucas County, IA, Lyon County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mills County, IA, Mitchell County, IA, Monona County, IA, Monroe County, IA, Montgomery County, IA, O'Brien County, IA, Osceola County, IA, Page County, IA, Palo Alto County, IA, Plymouth County, IA, Pocahontas County, IA, Polk County, IA, Pottawattamie County, IA, Poweshiek County, IA, Ringgold County, IA, Sac County, IA, Shelby County, IA, Sioux County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Winnebago County, IA, Woodbury County, IA, Worth County, IA, Wright County, IA, Blue Earth County, MN, Cottonwood County, MN, Faribault County, MN, Freeborn County, MN, Jackson County, MN, Martin County, MN, Mower County, MN, Nobles County, MN, Waseca County, MN, Watonwan County, MN, Burt County, NE, Cass County, NE, Cuming County, NE, Dakota County, NE, Dodge County, NE, Douglas County, NE, Sarpy County, NE, Saunders County, NE, Thurston County, NE, Washington County, NE, Union County, SD
The radar
The Des Moines radar (KDMX), 105 km from the middle of the area, began a volume at 20:01 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
Omaha, NE (KOAX), launched 12:00Z, 8.0 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.
- Mixed-layer CAPE
- 181 J/kg
- Mixed-layer CIN
- -155 J/kg
- Mixed-layer LCL
- 1277 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km storm-relative helicity
- 103 m²/s²
- 0-3 km storm-relative helicity
- 35 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 101958 SWOMCD SPC MCD 101957 IAZ000-MNZ000-NEZ000-SDZ000-102200- MESOSCALE DISCUSSION 0539 NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT SUN APR 10 2005 AREAS AFFECTED...CENTRAL AND WRN IA / FAR ERN NEBRASKA / SERN TIP OF SD / FAR SRN MN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 101957Z - 102200Z THREAT FOR SEVERE THUNDERSTORMS IS INCREASING. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. 19Z SURFACE ANALYSIS SHOWS INVERTED TROUGH EXTENDING FROM WRN IA SWWD ACROSS SERN NEBRASKA AND INTO KS. AIR MASS HAS BECOME MODERATELY UNSTABLE WITH MUCAPE NEAR 1500 J/KG. GREATEST THREAT FOR ORGANIZED SEVERE STORMS MAY COME FROM EVOLVING CONVECTIVE CLUSTERS NOW OVER NRN KS / SRN NEBRASKA...AS THEY ENCOUNTER AN INCREASINGLY UNSTABLE AIR MASS TO THEIR NE. THESE CLUSTERS WERE INITIALLY BEING FED BY SLY LOW LEVEL JET AND ASSOCIATED INSTABILITY AXIS OVER SRN KS / NRN OK...BUT WILL LIKELY TRANSITION TO BEING MORE OF A FORWARD-PROPAGATING SYSTEM AS MAIN SOURCE OF STORM RELATIVE INFLOW AIR STARTS COMING OUT OF THE E AND NE. DAMAGING WINDS WOULD BE LIKELY WITH THIS SCENARIO. LARGE HAIL WOULD LIKELY OCCUR AS WELL DUE TO COLD TEMPERATURE PROFILES ALOFT. IN ADDITION...ALTHOUGH FORCING IS SHALLOW/WEAK...ISOLATED SEVERE STORMS WITH LARGE HAIL MAY FORM AHEAD OF APPROACHING CONVECTIVE CLUSTERS. ..JEWELL.. 04/10/2005 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DVN...ARX...MPX...DMX...FSD...OAX... 40649579 41029712 43299662 44209517 44199366 43159178 40669253
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 9, 9:35 PM CDT | Mesoscale Discussion | SPC | Lyon, Sioux | 115 min |
| Apr 10, 3:55 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Audubon, Boone, Buena Vista, Calhoun and 37 more | 7 hr |
| Apr 9, 7:19 PM CDT | Mesoscale Discussion | SPC | Adams, Antelope, Arthur, Blaine, Boone, Buffalo and 33 more | 2 hr |
| Apr 9, 8:25 PM CDT | Severe Thunderstorm Watch | SPC | Antelope, Blaine, Boone, Brown, Buffalo, Custer and 24 more | 7 hr |
| Apr 9, 11:08 PM CDT | Mesoscale Discussion | SPC | Antelope, Blaine, Boyd, Brown, Buffalo, Custer and 21 more | 2 hr |
| Apr 10, 2:33 AM CDT | Mesoscale Discussion | SPC | Antelope, Blaine, Boone, Boyd, Brown, Buffalo and 26 more | 57 min |
| Apr 10, 1:07 PM CDT | Mesoscale Discussion | SPC | Clay, Fillmore, Gage, Jefferson, Johnson, Nuckolls and 4 more | 113 min |
| Apr 10, 1:40 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Buffalo, Clay, Fillmore, Franklin, Furnas and 19 more | 6 hr |
| Apr 10, 3:31 PM CDT | Mesoscale Discussion | SPC | Adams, Buffalo, Clay, Fillmore, Franklin, Gage and 19 more | 89 min |
Nearby
Mesoscale Discussions in Iowa, 2005Mesoscale Discussions in Minnesota, 2005Mesoscale Discussions in Nebraska, 2005Every mesoscale discussion in 2005
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.