Alert archive / Iowa / Mesoscale Discussions in 2014

Mesoscale Discussion 1213

June 30, 201413 counties in Iowa; 4 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Jun 30, 2014, 10:48 AM CDT for 13 counties in Iowa; 4 counties in Nebraska. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued
Jun 30, 2014, 10:48 AM CDT (15:48 UTC)
Expired
Jun 30, 2014, 12:15 PM CDT
In force
87 min
Issued by
the Storm Prediction Center

Counties Audubon County, IA, Calhoun County, IA, Carroll County, IA, Crawford County, IA, Greene County, IA, Guthrie County, IA, Harrison County, IA, Ida County, IA, Monona County, IA, Sac County, IA, Shelby County, IA, Webster County, IA, Woodbury County, IA, Burt County, NE, Cuming County, NE, Dakota County, NE, Thurston County, NE

The radar

The Omaha radar (KOAX), 93 km from the middle of the area, began a volume at 15:50 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 12:00Z, 3.8 hours before the alert went out and 94 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, Omaha, NE at 12:00Z on 2014-06-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4563 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, Omaha, NE at 12:00Z on 2014-06-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 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
4563 J/kg
Mixed-layer CIN
-72 J/kg
Mixed-layer LCL
903 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
162 m²/s²
Significant tornado parameter
2.8
Supercell composite
12.1

Open this sounding in Storm Lab

The text

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

212 
ACUS11 KWNS 301548
SWOMCD
SPC MCD 301548 
IAZ000-NEZ000-SDZ000-301715-

MESOSCALE DISCUSSION 1213
NWS STORM PREDICTION CENTER NORMAN OK
1048 AM CDT MON JUN 30 2014

AREAS AFFECTED...NERN NEB INTO WEST CENTRAL AND CENTRAL IA

CONCERNING...TORNADO WATCH 373...

VALID 301548Z - 301715Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 373 CONTINUES.

SUMMARY...THROUGH AT LEAST 16-17Z...AN INCREASING THREAT FOR
DAMAGING WINDS EXISTS FROM FAR NERN NEBRASKA INTO WEST CENTRAL AND
CENTRAL IOWA ATTENDANT TO A FAST-MOVING BOWING LINE OF STORMS.

DISCUSSION...TRENDS IN MORNING RADAR IMAGERY SHOWED CLUSTERS OF
STORMS HAD GROWN UPSCALE INTO A FAST-MOVING BOWING LINE OF
STORMS...NOW LOCATED IN FAR NERN NEB.  THIS BOW...MOVING EAST AT 50
KT...PRODUCED AN OBSERVED WIND GUST TO 51 KT AT 1450Z AT NORFOLK,
NEBRASKA AND WILL BEGIN TO AFFECT ADJACENT WEST CENTRAL IA /SRN
PLYMOUTH COUNTY TO HARRISON COUNTY/ BY 16Z.  AT THAT FAST FORWARD
SPEED...SIGNIFICANT WIND DAMAGE IS POSSIBLE.  THE EWD TRACK IS
EXPECTED TO BE MAINTAINED...AT LEAST IN THE SHORT TERM /THROUGH
17-18Z/...WITH THIS BOW MOVING ALONG A STRONG INSTABILITY GRADIENT.

..PETERS.. 06/30/2014

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

ATTN...WFO...DMX...FSD...OAX...

LAT...LON   41769722 42029689 42389678 42559676 42519554 42489406
            42219394 41619426 41549471 41619627 41769722

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 29, 7:50 PM CDTMesoscale DiscussionSPCBuchanan, Clayton, Delaware, Dubuque, Fayette, Jackson and 2 more85 min
Jun 29, 8:15 PM CDTSevere Thunderstorm WatchSPCAllamakee, Benton, Buchanan, Cedar, Chickasaw, Clayton and 14 more7 hr
Jun 29, 9:43 PM CDTMesoscale DiscussionSPCAllamakee, Buchanan, Cedar, Clayton, Clinton, Delaware and 6 more92 min
Jun 29, 10:10 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Clarke, Dallas, Decatur and 16 more65 min
Jun 29, 10:54 PM CDTTornado WatchSPCClinton, Jackson5 hr
Jun 30, 3:32 AM CDTMesoscale DiscussionSPCAudubon, Boone, Calhoun, Carroll, Cherokee, Crawford and 15 more58 min
Jun 30, 4:06 AM CDTSevere Thunderstorm WatchSPCAdair, Adams, Appanoose, Audubon, Boone, Calhoun and 42 more10 hr
Jun 30, 7:16 AM CDTMesoscale DiscussionSPCAudubon, Benton, Black Hawk, Boone, Bremer, Buchanan and 36 more89 min
Jun 30, 9:08 AM CDTMesoscale DiscussionSPCAdair, Adams, Cass, Harrison, Mills, Montgomery and 2 more67 min
Jun 30, 9:38 AM CDTTornado WatchSPCAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 46 more10 hr
Jun 30, 1:27 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Benton, Black Hawk and 60 more93 min
Jun 30, 2:03 PM CDTTornado WatchSPCBenton, Buchanan, Cedar, Clayton, Clinton, Delaware and 17 more5 hr
Jun 30, 3:17 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Boone, Carroll and 28 more58 min
Jun 30, 3:25 PM CDTMesoscale DiscussionSPCAllamakee, Benton, Buchanan, Cedar, Clayton, Clinton and 18 more35 min
Jun 30, 6:28 PM CDTMesoscale DiscussionSPCBenton, Cedar, Clinton, Dubuque, Iowa, Jackson and 10 more92 min
Jun 29, 11:53 PM CDTMesoscale DiscussionSPCAdams, Buffalo, Clay, Custer, Dawson, Franklin and 13 more97 min
Jun 30, 1:02 AM CDTSevere Thunderstorm WatchSPCAdams, Antelope, Blaine, Boone, Brown, Buffalo and 31 more10 hr
Jun 30, 12:06 PM CDTMesoscale DiscussionSPCPawnee, Richardson54 min
Jun 30, 3:52 PM CDTMesoscale DiscussionSPCGage, Johnson, Nemaha, Pawnee, Richardson113 min

Nearby

Mesoscale Discussions in Iowa, 2014Mesoscale Discussions in Nebraska, 2014Every mesoscale discussion in 2014

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.