Alert archive / Arkansas / Mesoscale Discussions in 2004

Mesoscale Discussion 496

April 29, 2004Ashley County, Chicot County, Drew County, Arkansas; Washington County, Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2004, 2:44 PM CDT for Ashley County, Chicot County, Drew County, Arkansas; Washington County, Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 29, 2004, 2:44 PM CDT (19:44 UTC)
Expired: Apr 29, 2004, 4:45 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

Counties Ashley County, AR, Chicot County, AR, Drew County, AR, Washington County, MS

The radar

The Little Rock radar (KLZK), 166 km from the middle of the area, began a volume at 19:46 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

Jackson, MS (KJAN), launched 12:00Z, 7.7 hours before the alert went out and 188 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1051 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 68 m²/s²
0-3 km storm-relative helicity: 169 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.

Issued	Product	Office	Counties	Lasted
Apr 29, 11:22 AM CDT	Mesoscale Discussion	SPC	Ashley, Bradley, Union	113 min
Apr 29, 1:10 PM CDT	Tornado Watch	SPC	Ashley, Bradley, Calhoun, Chicot, Drew, Union	6 hr
Apr 29, 5:36 PM CDT	Mesoscale Discussion	SPC	Chicot	84 min
Apr 29, 1:56 PM CDT	Mesoscale Discussion	SPC	Adams, Amite, Claiborne, Copiah, Covington, Forrest and 23 more	2 hr
Apr 29, 3:15 PM CDT	Tornado Watch	SPC	George, Hancock, Harrison, Jackson, Stone	6 hr
Apr 29, 6:15 PM CDT	Mesoscale Discussion	SPC	George, Hancock, Harrison, Jackson, Pearl River, Stone	90 min
Apr 29, 6:55 PM CDT	Tornado Watch	SPC	Attala, Carroll, Choctaw, Hinds, Holmes, Leake and 5 more	3 hr

Nearby

Mesoscale Discussions in Arkansas, 2004 Mesoscale Discussions in Mississippi, 2004 Every mesoscale discussion in 2004

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.