Alert archive / Texas / Mesoscale Discussions in 2018
Mesoscale Discussion 75
The Storm Prediction Center issued this mesoscale discussion at Feb 20, 2018, 8:52 AM CST for 4 counties in Oklahoma; 26 counties in Texas. It was in force for 113 min.
The area
The outline as issued.
The facts
- Issued
- Feb 20, 2018, 8:52 AM CST (14:52 UTC)
- Expired
- Feb 20, 2018, 10:45 AM CST
- In force
- 113 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 30 counties
Carter County, OK, Johnston County, OK, Love County, OK, Marshall County, OK, Bell County, TX, Bosque County, TX, Burnet County, TX, Collin County, TX, Comanche County, TX, Cooke County, TX, Coryell County, TX, Dallas County, TX, Denton County, TX, Ellis County, TX, Erath County, TX, Grayson County, TX, Hamilton County, TX, Hill County, TX, Hood County, TX, Johnson County, TX, Lampasas County, TX, Llano County, TX, McLennan County, TX, Mills County, TX, Montague County, TX, Parker County, TX, San Saba County, TX, Somervell County, TX, Tarrant County, TX, Wise County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 19 km from the middle of the area, began a volume at 14:54 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
Fort Worth, TX (KFWD), launched 12:00Z, 2.9 hours before the alert went out and 21 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.
- Mixed-layer CAPE
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 850 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- -7 m²/s²
- 0-3 km storm-relative helicity
- 141 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 20, 4:21 AM CST | Mesoscale Discussion | SPC | Alfalfa, Woods, Woodward | 3 hr |
| Feb 20, 9:40 AM CST | Mesoscale Discussion | SPC | Cleveland, Creek, Grady, Lincoln, Logan, McClain and 6 more | 4 hr |
| Feb 20, 11:11 AM CST | Mesoscale Discussion | SPC | Carter, Jefferson, Love | 94 min |
| Feb 19, 10:07 PM CST | Mesoscale Discussion | SPC | Bandera, Brown, Coleman, Comanche, Concho, Edwards and 13 more | 53 min |
Nearby
Mesoscale Discussions in Texas, 2018Mesoscale Discussions in Oklahoma, 2018Every mesoscale discussion in 2018
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.