Alert archive / Arkansas / Mesoscale Discussions in 2009

Mesoscale Discussion 418

April 9, 20095 states

The Storm Prediction Center issued this mesoscale discussion at Apr 9, 2009, 6:59 PM CDT for 5 states. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Apr 9, 2009, 6:59 PM CDT (23:59 UTC)
Expired
Apr 9, 2009, 8:30 PM CDT
In force
91 min
Issued by
the Storm Prediction Center
All 73 counties

Baxter County, AR, Benton County, AR, Boone County, AR, Carroll County, AR, Conway County, AR, Crawford County, AR, Faulkner County, AR, Franklin County, AR, Garland County, AR, Howard County, AR, Johnson County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Montgomery County, AR, Newton County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Pope County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Sevier County, AR, Stone County, AR, Van Buren County, AR, Washington County, AR, Yell County, AR, Allen County, KS, Bourbon County, KS, Cherokee County, KS, Crawford County, KS, Labette County, KS, Linn County, KS, Neosho County, KS, Barry County, MO, Barton County, MO, Bates County, MO, Benton County, MO, Camden County, MO, Cedar County, MO, Christian County, MO, Dade County, MO, Dallas County, MO, Douglas County, MO, Greene County, MO, Hickory County, MO, Howell County, MO, Jasper County, MO, Laclede County, MO, Lawrence County, MO, McDonald County, MO, Newton County, MO, Ozark County, MO, Polk County, MO, St. Clair County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Vernon County, MO, Webster County, MO, Wright County, MO, Adair County, OK, Cherokee County, OK, Craig County, OK, Delaware County, OK, Haskell County, OK, Latimer County, OK, LeFlore County, OK, McCurtain County, OK, Ottawa County, OK, Sequoyah County, OK, Red River County, TX

The radar

The Western Arkansas radar (KSRX), 111 km from the middle of the area, began a volume at 00:00 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

Springfield, MO (KSGF), launched 12:00Z, 12.0 hours before the alert went out and 82 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, Springfield, MO at 12:00Z on 2009-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Springfield, MO at 12:00Z on 2009-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 371 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2492 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
371 m²/s²
0-3 km storm-relative helicity
549 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 9, 1:44 PM CDTTornado WatchSPCBenton, Carroll, Crawford, Franklin, Howard, Little River and 7 more7 hr
Apr 9, 5:39 PM CDTMesoscale DiscussionSPCBenton, Crawford, Franklin, Polk, Scott, Sebastian and 2 more2 hr
Apr 9, 12:57 PM CDTMesoscale DiscussionSPCAllen, Butler, Chautauqua, Cherokee, Cowley, Crawford and 13 more63 min
Apr 9, 4:30 PM CDTMesoscale DiscussionSPCEdwards, Kingman, Pawnee, Pratt, Reno, Sedgwick and 2 more60 min
Apr 9, 4:53 PM CDTTornado WatchSPCEdwards, Harvey, Kingman, Kiowa, Pratt, Reno and 3 more100 min
Apr 9, 6:14 PM CDTMesoscale DiscussionSPCHarvey, Pratt, Reno, Sedgwick, Stafford61 min
Apr 9, 12:47 PM CDTMesoscale DiscussionSPCAtoka, Cherokee, Coal, Creek, Haskell, Hughes and 18 more2 hr
Apr 9, 2:39 PM CDTMesoscale DiscussionSPCAnderson, Dallas, Delta, Ellis, Freestone, Henderson and 9 more111 min
Apr 9, 6:21 PM CDTMesoscale DiscussionSPCAustin, Brazos, Burleson, Fayette, Grimes, Lavaca and 5 more54 min

Nearby

Mesoscale Discussions in Arkansas, 2009Mesoscale Discussions in Missouri, 2009Mesoscale Discussions in Oklahoma, 2009Every 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.