Alert archive / Texas / Mesoscale Discussions in 2016

Mesoscale Discussion 411

April 18, 2016Fort Bend County, Harris County, Liberty County, Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 18, 2016, 5:10 AM CDT for Fort Bend County, Harris County, Liberty County, Texas. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued
Apr 18, 2016, 5:10 AM CDT (10:10 UTC)
Expired
Apr 18, 2016, 6:45 AM CDT
In force
95 min
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Fort Bend County, TX, Harris County, TX, Liberty County, TX

The radar

The Houston radar (KHGX), 48 km from the middle of the area, began a volume at 10:10 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

Lake Charles Mun, LA (KLCH), launched 00:00Z, 10.2 hours before the alert went out and 205 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, Lake Charles Mun, LA at 00:00Z on 2016-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 466 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, Lake Charles Mun, LA at 00:00Z on 2016-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 88 square meters per square second.193958Sfc1 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
466 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
736 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
88 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.8

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 17, 8:21 PM CDTMesoscale DiscussionSPCStarr, Zapata84 min
Apr 18, 12:02 AM CDTMesoscale DiscussionSPCHarris, Liberty, Montgomery, San Jacinto118 min
Apr 18, 4:29 AM CDTMesoscale DiscussionSPCKinney, Medina, Uvalde61 min
Apr 18, 12:57 PM CDTMesoscale DiscussionSPCBrooks, Cameron, Dimmit, Duval, Hidalgo, Jim Hogg and 10 more2 hr
Apr 18, 3:21 PM CDTSevere Thunderstorm WatchSPCBrooks, Cameron, Duval, Hidalgo, Jim Hogg, Jim Wells and 7 more8 hr
Apr 18, 5:54 PM CDTMesoscale DiscussionSPCBrooks, Cameron, Dimmit, Duval, Hidalgo, Jim Hogg and 10 more2 hr

Nearby

Mesoscale Discussions in Texas, 2016Every mesoscale discussion in 2016

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.