Alert archive / Iowa / Mesoscale Discussions in 2012

Mesoscale Discussion 292

March 19, 201219 counties in Iowa; 18 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Mar 19, 2012, 3:40 PM CDT for 19 counties in Iowa; 18 counties in Missouri. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued
Mar 19, 2012, 3:40 PM CDT (20:40 UTC)
Expired
Mar 19, 2012, 5:15 PM CDT
In force
95 min
Issued by
the Storm Prediction Center
All 37 counties

Appanoose County, IA, Boone County, IA, Clarke County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Polk County, IA, Story County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Adair County, MO, Caldwell County, MO, Carroll County, MO, Chariton County, MO, Daviess County, MO, Grundy County, MO, Harrison County, MO, Howard County, MO, Lafayette County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Mercer County, MO, Putnam County, MO, Randolph County, MO, Saline County, MO, Schuyler County, MO, Sullivan County, MO

The radar

The Des Moines radar (KDMX), 149 km from the middle of the area, began a volume at 20:40 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

Topeka, KS (KTOP), launched 12:00Z, 8.7 hours before the alert went out and 238 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 2012-03-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 920 joules per kilogram.LCLLFCEL10008507005003002001001 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 2012-03-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 212 square meters per square second.19395878Sfc1 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
920 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
712 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
212 m²/s²
0-3 km storm-relative helicity
179 m²/s²
Significant tornado parameter
0.4
Supercell composite
1.3

Open this sounding in Storm Lab

The text

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

128 
ACUS11 KWNS 192041
SWOMCD
SPC MCD 192040
IAZ000-MOZ000-192215-

MESOSCALE DISCUSSION 0292
NWS STORM PREDICTION CENTER NORMAN OK
0340 PM CDT MON MAR 19 2012

AREAS AFFECTED...NORTHERN MO/CENTRAL IA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 192040Z - 192215Z

AT LEAST A FEW SEVERE TSTMS CAPABLE OF HAIL/GUSTY WINDS AND PERHAPS
EVEN A BRIEF TORNADO WILL BE POSSIBLE INTO EARLY EVENING ACROSS
PORTIONS OF NORTHERN MO/CENTRAL IA. A WATCH DOES NOT APPEAR LIKELY
OR IMMINENT AT THIS TIME...BUT CONVECTIVE TRENDS WILL CONTINUE TO BE
MONITORED.

SCATTERED TSTMS ARE GENERALLY FOCUSED AT MID AFTERNOON ALONG
CONVECTIVE OUTFLOW/ZONE OF CONFLUENCE WITHIN A GENERAL NORTH-SOUTH
CORRIDOR ACROSS NORTHERN MO/CENTRAL IA...WITH SOME ADDITIONAL STORMS
IN THE EASTWARD ADJACENT WARM SECTOR ACROSS NORTH-CENTRAL/NORTHEAST
MO AND FAR SOUTH-CENTRAL IA. DESTABILIZATION HAS BEEN TEMPERED IN
THE IMMEDIATE VICINITY OF THE OUTFLOW OWING TO PERSIST CLOUD
COVER...BUT LITTLE INHIBITION EXISTS IN THE ADJACENT WARM SECTOR
WHERE TEMPERATURES HAVE REACHED THE UPPER 70S/LOWER 80S F. IN THE
PRESENCE OF STRONG DEEP SOUTHERLY FLOW...SUFFICIENT
INSTABILITY/LAPSE RATES EXIST FOR SOME THREAT FOR SEVERE HAIL/WINDS.
FURTHERMORE...IT MAY NOT BE OUT OF THE QUESTION FOR STORMS IN THE
NEARBY WARM SECTOR TO ACQUIRE SOME ROTATION GIVEN THE
STRENGTH/BACKING OF LOW LEVEL FLOW PER REGIONAL WSR-88D VWPS/SURFACE
DATA...SUCH THAT A BRIEF TORNADO CANNOT BE RULED OUT.

..GUYER.. 03/19/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LSX...DVN...DMX...EAX...

LAT...LON   40269420 42659436 41209212 38979237 39059394 40269420

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 19, 1:34 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 30 more116 min
Mar 19, 6:43 PM CDTMesoscale DiscussionSPCBenton, Black Hawk, Bremer, Buchanan, Butler, Cerro Gordo and 11 more62 min
Mar 19, 3:55 PM CDTMesoscale DiscussionSPCMcDonald95 min

Nearby

Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Missouri, 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.