Alert archive / Arkansas / Mesoscale Discussions in 2003

Mesoscale Discussion 509

April 19, 20039 counties in Arkansas

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2003, 9:40 PM CDT for 9 counties in Arkansas. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Apr 19, 2003, 9:40 PM CDT (02:40 UTC)
Expired
Apr 19, 2003, 10:45 PM CDT
In force
65 min
Issued by
the Storm Prediction Center

Counties Baxter County, AR, Boone County, AR, Carroll County, AR, Franklin County, AR, Johnson County, AR, Madison County, AR, Marion County, AR, Newton County, AR, Searcy County, AR

The radar

The Springfield radar (KSGF), 128 km from the middle of the area, began a volume at 02:42 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 00:00Z, 2.7 hours before the alert went out and 103 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 00:00Z on 2003-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 11 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, Springfield, MO at 00:00Z on 2003-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 286 square meters per square second.1939587897Sfc1 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
11 J/kg
Mixed-layer CIN
-140 J/kg
Mixed-layer LCL
902 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
286 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

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 19, 7:54 PM CDTMesoscale DiscussionSPCPolk, Sebastian96 min
Apr 19, 8:55 PM CDTSevere Thunderstorm WatchSPCBenton, Crawford, Sebastian, Washington5 hr
Apr 19, 10:35 PM CDTSevere Thunderstorm WatchSPCBaxter, Boone, Carroll, Franklin, Johnson, Madison and 5 more5 hr
Apr 19, 10:42 PM CDTMesoscale DiscussionSPCBenton, Crawford, Sebastian, Washington93 min
Apr 20, 1:25 AM CDTMesoscale DiscussionSPCBaxter, Boone, Clay, Cleburne, Craighead, Fulton and 13 more2 hr
Apr 20, 4:00 AM CDTMesoscale DiscussionSPCClay2 hr
Apr 20, 11:52 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Cleveland, Craighead, Crittenden, Cross and 8 more2 hr
Apr 20, 1:00 PM CDTMesoscale DiscussionSPCCrittenden, Lee, Mississippi3 hr
Apr 20, 3:02 PM CDTMesoscale DiscussionSPCAshley, Chicot, Desha, Drew3 hr

Nearby

Mesoscale Discussions in Arkansas, 2003Every mesoscale discussion in 2003

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.