Alert archive / Iowa / Mesoscale Discussions in 2011
Mesoscale Discussion 772
The Storm Prediction Center issued this mesoscale discussion at May 12, 2011, 10:27 PM CDT for 37 counties in Iowa. It was in force for 63 min.
The area
The outline as issued.
The facts
- Issued
- May 12, 2011, 10:27 PM CDT (03:27 UTC)
- Expired
- May 12, 2011, 11:30 PM CDT
- In force
- 63 min
- Issued by
- the Storm Prediction Center
All 37 counties
Adair County, IA, Adams County, IA, Audubon County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Clarke County, IA, Dallas County, IA, Franklin County, IA, Fremont County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hardin County, IA, Jasper County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Polk County, IA, Pottawattamie County, IA, Poweshiek County, IA, Shelby County, IA, Story County, IA, Tama County, IA, Union County, IA, Warren County, IA, Webster County, IA, Wright County, IA
The radar
The Des Moines radar (KDMX), 63 km from the middle of the area, began a volume at 03:27 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 nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 3.5 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
- 1648 J/kg
- Mixed-layer CIN
- -45 J/kg
- Mixed-layer LCL
- 900 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 19 m²/s²
- 0-3 km storm-relative helicity
- 50 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.6
The text
As transmitted, in the capitals the NWS used until 2016.
994
ACUS11 KWNS 130328
SWOMCD
SPC MCD 130327
IAZ000-NEZ000-130430-
MESOSCALE DISCUSSION 0772
NWS STORM PREDICTION CENTER NORMAN OK
1027 PM CDT THU MAY 12 2011
AREAS AFFECTED...WESTERN/CENTRAL IA
CONCERNING...SEVERE THUNDERSTORM WATCH 295...
VALID 130327Z - 130430Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 295
CONTINUES.
SEVERE TSTM WATCH 295 CONTINUES UNTIL 06Z ACROSS PORTIONS OF
WESTERN/CENTRAL IA...WITH CONTINUED POTENTIAL FOR SEVERE HAIL.
STRONG/SEVERE TSTM DEVELOPMENT WILL CONTINUE TO FAVOR THE COOL
/NORTH/ SIDE A SOUTHEASTWARD SAGGING SURFACE FRONT THAT EXTENDS
NORTHEASTWARD FROM THE OMAHA AREA TO NORTHEAST IA...WITH ADDITIONAL
TSTM DEVELOPMENT ANTICIPATED TO OCCUR INTO SOUTHWEST/SOUTH-CENTRAL
IA OVERNIGHT. PER THE 00Z OMAHA OBSERVED RAOB AND MORE CONTEMPORARY
RUC SOUNDINGS...STEEP LAPSE RATES ALOFT AND AMPLE ELEVATED
INSTABILITY/EFFECTIVE SHEAR EXISTS ESPECIALLY IN VICINITY OF THE
AFOREMENTIONED BOUNDARY TO MAINTAIN A SEVERE HAIL THREAT LATE THIS
EVENING AND POTENTIALLY INTO THE OVERNIGHT.
..GUYER.. 05/13/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...DVN...ARX...DMX...OAX...
LAT...LON 41069610 41339614 42049518 42869391 43059261 42539203
41219263 40599567 41069610SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 12, 9:16 PM CDT | Mesoscale Discussion | SPC | Fremont, Harrison, Mills, Page, Pottawattamie | 59 min |
Nearby
Mesoscale Discussions in Iowa, 2011Every mesoscale discussion in 2011
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.