Alert archive / Iowa / Mesoscale Discussions in 2012
Mesoscale Discussion 536
The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2012, 7:50 PM CDT for 19 counties in Iowa. It was in force for 55 min.
The area
The outline as issued.
The facts
- Issued
- Apr 14, 2012, 7:50 PM CDT (00:50 UTC)
- Expired
- Apr 14, 2012, 8:45 PM CDT
- In force
- 55 min
- Issued by
- the Storm Prediction Center
Counties Benton County, IA, Buchanan County, IA, Cedar County, IA, Delaware County, IA, Henry County, IA, Iowa County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Louisa County, IA, Mahaska County, IA, Muscatine County, IA, Poweshiek County, IA, Tama County, IA, Van Buren County, IA, Wapello County, IA, Washington County, IA
The radar
The Quad Cities radar (KDVN), 106 km from the middle of the area, began a volume at 00:51 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 00:00Z, 0.8 hours before the alert went out and 113 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
- 300 J/kg
- Mixed-layer CIN
- -50 J/kg
- Mixed-layer LCL
- 726 m above ground
- 0-6 km bulk shear
- 69 kt
- 0-1 km storm-relative helicity
- 124 m²/s²
- 0-3 km storm-relative helicity
- 126 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.0
The text
As transmitted, in the capitals the NWS used until 2016.
975
ACUS11 KWNS 150051
SWOMCD
SPC MCD 150050
IAZ000-ILZ000-MOZ000-150145-
MESOSCALE DISCUSSION 0536
NWS STORM PREDICTION CENTER NORMAN OK
0750 PM CDT SAT APR 14 2012
AREAS AFFECTED...ERN IA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 150050Z - 150145Z
AN ORGANIZED BOWING SEGMENT CONTINUES TO TRACK EWD...AND IS EXPECTED
TO PROGRESS TO THE ERN PORTION OF WW 169 BY 02Z. THE SYSTEM MAY
WEAKEN WITH TIME...BUT ITS ORGANIZATION WILL CONTINUE TO BE
MONITORED...WITH THE POSSIBILITY OF A DOWNSTREAM SEVERE WW.
AN MCV LOCATED JUST EAST OF ATLANTIC IA CONTINUES TO TRACK
EWD...WITH AN ORGANIZED COLD POOL NOW EVIDENT. ALTHOUGH CONDITIONS
REMAIN FAVORABLE FOR DMGG WINDS AND POSSIBLE EMBEDDED MESOVORTICES
ATTM...DOWNSTREAM 00Z SOUNDINGS SHOW LIMITED
INSTABILITY/MOISTURE...WHICH MAY WEAKEN THE SYSTEM AS IT APPROACHES
THE ERN EXTENT OF WW 169. HOWEVER...A STRENGTHENING LOW LEVEL JET
COULD LEAD TO AT LEAST WEAK MOISTURE RETURN...WITH A SUPPORTING
UPPER WAVE NOTED ON WV IMAGERY ACROSS ERN NEB POSSIBLY SUSTAINING
THE BOWING SEGMENT. AS SUCH...ISOLATED OCCURRENCES OF DMGG WINDS
AND/OR HAIL WILL BE POSSIBLE.
..HURLBUT.. 04/15/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...DVN...DMX...
LAT...LON 41859289 42619203 42419093 41869064 41279087 40789136
40519174 40609233 41519282 41859289SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 14, 7:51 PM CDT | Mesoscale Discussion | SPC | Cherokee, Ida, Lyon, Monona, O'Brien, Osceola and 3 more | 84 min |
| Apr 14, 8:41 PM CDT | Severe Thunderstorm Watch | SPC | Cedar, Clinton, Des Moines, Henry, Iowa, Jackson and 9 more | 4 hr |
| Apr 14, 9:54 PM CDT | Mesoscale Discussion | SPC | Cedar, Clinton, Jackson, Jones, Louisa, Muscatine and 1 more | 96 min |
| Apr 14, 10:09 PM CDT | Severe Thunderstorm Watch | SPC | Fremont, Harrison, Mills, Monona, Montgomery, Page and 3 more | 6 hr |
| Apr 14, 11:28 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Boone, Carroll and 28 more | 92 min |
| Apr 15, 3:25 AM CDT | Mesoscale Discussion | SPC | Adams, Audubon, Cass, Fremont, Harrison, Mills and 5 more | 95 min |
| Apr 15, 1:56 PM CDT | Mesoscale Discussion | SPC | Audubon, Boone, Buena Vista, Butler, Calhoun, Carroll and 28 more | 94 min |
| Apr 15, 3:37 PM CDT | Tornado Watch | SPC | Cerro Gordo, Chickasaw, Clay, Dickinson, Emmet, Floyd and 8 more | 7 hr |
Nearby
Mesoscale Discussions in Iowa, 2012Every mesoscale discussion in 2012
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.