Alert archive / Iowa / Mesoscale Discussions in 2019
Mesoscale Discussion 1321
The Storm Prediction Center issued this mesoscale discussion at Jun 30, 2019, 5:20 PM CDT for 5 counties in Illinois; 27 counties in Iowa; 4 counties in Wisconsin. It was in force for 115 min.
The area
The outline as issued.
The facts
- Issued
- Jun 30, 2019, 5:20 PM CDT (22:20 UTC)
- Expired
- Jun 30, 2019, 7:15 PM CDT
- In force
- 115 min
- Issued by
- the Storm Prediction Center
All 36 counties
Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cedar County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Iowa County, IA, Jackson County, IA, Johnson County, IA, Jones County, IA, Linn County, IA, Marshall County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Tama County, IA, Carroll County, IL, Jo Daviess County, IL, Rock Island County, IL, Stephenson County, IL, Whiteside County, IL, Grant County, WI, Green County, WI, Iowa County, WI, Lafayette County, WI
The radar
The Quad Cities radar (KDVN), 143 km from the middle of the area, began a volume at 22:22 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
Davenport, (KDVN), launched 12:00Z, 10.3 hours before the alert went out and 147 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
- 1910 J/kg
- Mixed-layer CIN
- -100 J/kg
- Mixed-layer LCL
- 1304 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 46 m²/s²
- 0-3 km storm-relative helicity
- 106 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.5
The text
As transmitted.
452
ACUS11 KWNS 302220
SWOMCD
SPC MCD 302220
ILZ000-WIZ000-IAZ000-010015-
Mesoscale Discussion 1321
NWS Storm Prediction Center Norman OK
0520 PM CDT Sun Jun 30 2019
Areas affected...Northeast Iowa...southwest Wisconsin...northwest
Illinois
Concerning...Severe Thunderstorm Watch 468...
Valid 302220Z - 010015Z
The severe weather threat for Severe Thunderstorm Watch 468
continues.
SUMMARY...The severe threat for WW468 continues with severe
wind/hail as the main threats. Storms may push/develop south and
east of the current watch and a local watch expansion may be
necessary.
DISCUSSION...A MCS continues to move south/southeast along an
instability gradient across northeast Iowa into southwest Wisconsin.
With 3000-4500 J/kg of MLCAPE ahead of the western portions of the
MCS, storms should continue to propagate/develop south/southeastward
into the evening. Given the storm mode and steep low-level lapse
rates ahead of the storms, severe wind is the most likely severe
threat. Large hail is also possible given relatively steep mid-level
lapse rates, the aforementioned large MLCAPE, and being on the
periphery of marginal effective bulk shear (30-35 knots).
Eastern portions of the MCS still has good inflow from the
southwest, but it will encounter a more stable airmass that was
convectively overturned by the previous MCS. However, there should
be corridor just outside of the current watch in northwest Illinois
and possibly southwest Wisconsin where the environment could support
severe storms. Additionally, given the current structure of the MCS
and instability ahead of it, it may move south of the watch in the
coming hours. Due to these likely scenarios, a local watch expansion
or a small new watch may be necessary.
..Nauslar/Thompson.. 06/30/2019
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LOT...MKX...DVN...ARX...DMX...
LAT...LON 43359355 43249265 43129217 43089172 43109138 43229090
43329024 43178964 42718949 42248945 41608971 41469012
41429074 41469197 41679275 41879312 42069336 42279345
42779358 43089356 43359355SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 11:43 AM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Carroll, Champaign, Cook, DeKalb and 29 more | 6 hr |
| Jun 30, 1:38 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, DeKalb, DuPage, Ford and 22 more | 2 hr |
| Jun 30, 2:52 PM CDT | Mesoscale Discussion | SPC | Champaign, Clark, Coles, Douglas, Edgar, Ford and 3 more | 113 min |
| Jun 30, 3:20 PM CDT | Severe Thunderstorm Watch | SPC | Carroll, Jo Daviess, Stephenson | 4 hr |
| Jun 30, 3:35 PM CDT | Severe Thunderstorm Watch | SPC | Clark, Clay, Coles, Crawford, Cumberland, Douglas and 8 more | 4 hr |
| Jun 30, 5:47 PM CDT | Mesoscale Discussion | SPC | Christian, Clark, Clay, Coles, Crawford, Cumberland and 19 more | 118 min |
| Jun 30, 5:54 PM CDT | Severe Thunderstorm Watch | SPC | Bureau, Henderson, Henry, Mercer, Rock Island, Warren and 1 more | 3 hr |
| Jun 30, 6:22 PM CDT | Severe Thunderstorm Watch | SPC | Edwards, Gallatin, Hamilton, Saline, Wabash, Wayne and 1 more | 2 hr |
| Jun 30, 3:06 PM CDT | Mesoscale Discussion | SPC | Allamakee, Bremer, Cerro Gordo, Chickasaw, Clayton, Delaware and 6 more | 84 min |
| Jun 30, 2:12 AM CDT | Mesoscale Discussion | SPC | Burnett, Douglas | 2 hr |
| Jun 30, 4:41 AM CDT | Mesoscale Discussion | SPC | Burnett, Dunn, Pepin, Pierce, Polk, Saint Croix | 2 hr |
| Jun 30, 5:11 AM CDT | Severe Thunderstorm Watch | SPC | Barron, Bayfield, Buffalo, Burnett, Chippewa, Clark and 17 more | 7 hr |
| Jun 30, 7:49 AM CDT | Mesoscale Discussion | SPC | Adams, Buffalo, Chippewa, Clark, Crawford, Dunn and 14 more | 116 min |
| Jun 30, 10:16 AM CDT | Mesoscale Discussion | SPC | Columbia, Dane, Dodge, Fond du Lac, Green Lake, Iowa and 7 more | 119 min |
Nearby
Mesoscale Discussions in Iowa, 2019Mesoscale Discussions in Illinois, 2019Mesoscale Discussions in Wisconsin, 2019Every mesoscale discussion in 2019
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.