Alert archive / Iowa / Mesoscale Discussions in 2009

Mesoscale Discussion 913

June 1, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Jun 1, 2009, 6:52 PM CDT for 4 states. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: Jun 1, 2009, 6:52 PM CDT (23:52 UTC)
Expired: Jun 1, 2009, 8:15 PM CDT
In force: 83 min
Issued by: the Storm Prediction Center

All 47 counties

Adams County, IA, Appanoose County, IA, Clarke County, IA, Davis County, IA, Decatur County, IA, Fremont County, IA, Keokuk County, IA, Lucas County, IA, Mahaska County, IA, Marion County, IA, Mills County, IA, Monroe County, IA, Montgomery County, IA, Page County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Jewell County, KS, Republic County, KS, Washington County, KS, Atchison County, MO, Gentry County, MO, Harrison County, MO, Holt County, MO, Mercer County, MO, Nodaway County, MO, Putnam County, MO, Schuyler County, MO, Worth County, MO, Cass County, NE, Fillmore County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Nuckolls County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Thayer County, NE, Webster County, NE

The radar

The Omaha radar (KOAX), 101 km from the middle of the area, began a volume at 23:52 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, 11.9 hours before the alert went out and 102 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 349 J/kg
Mixed-layer CIN: -150 J/kg
Mixed-layer LCL: 1784 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 39 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 012353
SWOMCD
SPC MCD 012352 
IAZ000-MOZ000-NEZ000-KSZ000-020115-

MESOSCALE DISCUSSION 0913
NWS STORM PREDICTION CENTER NORMAN OK
0652 PM CDT MON JUN 01 2009

AREAS AFFECTED...NRN KS...SERN NEB...SRN IA...EXTREME NRN MO

CONCERNING...SEVERE THUNDERSTORM WATCH 319...

VALID 012352Z - 020115Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 319
CONTINUES.

HIGH CAPE AND RELATIVELY WEAK SHEAR EVENT IS UNDERWAY ACROSS THE
REGION THIS EVENING.  AREA PROFILERS SUGGEST WEAK TROPOSPHERIC FLOW
AMIDST MLCAPES 2000-2500 J/KG AND MID-LVL LAPSE RATES IN EXCESS OF
7-7.5 DEG C PER KM.  MODEST LLVL CONVERGENCE ALONG AN E-W ORIENTED
FRONT ALONG NRN EDGE OF STRONGER INSTABILITY WAS SUFFICIENT FOR
RAPID DEVELOPMENT OF VIGOROUS TSTMS.  ANY PARTICULAR STORM UPDRAFT
HAS TENDED TO BE SHORT-LIVED WITH OUTFLOW GENERATING RATHER RANDOM
DEVELOPMENT ALONG N AND S FLANKS OF THE FRONT.  SHORT TERM MODELS
INDICATE THAT A SWLY LLJ OF 25-30 KTS WILL IMPINGE ON THE ACTIVITY
OVER NERN KS/SERN NEB THROUGH THE EVENING.  THIS WILL FAVOR THE
REGION FROM THE QUAD-STATE REGION OF NE/KS/IA/MO EWD ALONG THE IA/MO
BORDER FOR SVRL HOURS OF TRAINING HVY RNFL.  OTHERWISE...LARGE HAIL
AND DMGG WIND RISKS WILL CONTINUE INTO MID-EVENING... ESPECIALLY
OVER SRN/WRN PORTIONS OF THE WW.

..RACY.. 06/01/2009

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

ATTN...WFO...DVN...DMX...EAX...OAX...TOP...GID...

LAT...LON   39959920 41139620 41489177 40529220 39639762 39959920

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 1, 1:31 PM CDT	Mesoscale Discussion	SPC	Clinton, Scott	59 min
Jun 1, 2:37 PM CDT	Severe Thunderstorm Watch	SPC	Scott	7 hr
Jun 1, 2:55 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Cass, Clarke, Decatur and 13 more	2 hr
Jun 1, 3:29 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Appanoose, Cass, Cedar, Clarke and 31 more	8 hr
Jun 1, 5:25 PM CDT	Mesoscale Discussion	SPC	Adams, Appanoose, Clarke, Davis, Decatur, Fremont and 12 more	2 hr

Nearby

Mesoscale Discussions in Iowa, 2009 Mesoscale Discussions in Nebraska, 2009 Mesoscale Discussions in Missouri, 2009 Every mesoscale discussion in 2009

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.