Alert archive / Texas / Severe Thunderstorm Watches in 2009
Severe Thunderstorm Watch 77
The Storm Prediction Center issued this severe thunderstorm watch at Mar 27, 2009, 11:48 AM CDT for 22 counties in Texas. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 27, 2009, 11:48 AM CDT (16:48 UTC)
- Expired
- Mar 27, 2009, 5:00 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 22 counties
Austin County, TX, Brazos County, TX, Burleson County, TX, Chambers County, TX, Grimes County, TX, Hardin County, TX, Harris County, TX, Houston County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Madison County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Polk County, TX, San Jacinto County, TX, Trinity County, TX, Tyler County, TX, Walker County, TX, Waller County, TX, Washington County, TX
The radar
The Houston radar (KHGX), 120 km from the middle of the area, began a volume at 16:50 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 27, 12:03 PM CDT | Tornado Warning | HGX | Burleson | 27 min |
| Mar 27, 1:32 PM CDT | Severe Thunderstorm Warning | LCH | Hardin, Jasper, Tyler | 58 min |
| Mar 27, 1:41 PM CDT | Tornado Warning | HGX | Houston, Madison | 34 min |
| Mar 27, 2:20 PM CDT | Severe Thunderstorm Warning | LCH | Hardin, Jasper, Newton, Tyler | 55 min |
| Mar 27, 2:28 PM CDT | Severe Thunderstorm Warning | HGX | Grimes | 32 min |
| Mar 27, 2:31 PM CDT | Severe Thunderstorm Warning | LCH | Jasper, Newton | 44 min |
| Mar 27, 2:35 PM CDT | Tornado Warning | LCH | Jasper, Newton | 40 min |
| Mar 27, 2:58 PM CDT | Severe Thunderstorm Warning | HGX | Grimes, Montgomery, Waller | 32 min |
| Mar 27, 3:15 PM CDT | Severe Thunderstorm Warning | HGX | Grimes, Montgomery, Waller | 45 min |
| Mar 27, 3:56 PM CDT | Severe Thunderstorm Warning | HGX | Liberty, Montgomery, Polk, San Jacinto | 34 min |
| Mar 27, 4:19 PM CDT | Tornado Warning | HGX | Liberty, Montgomery, San Jacinto | 26 min |
| Mar 27, 4:30 PM CDT | Severe Thunderstorm Warning | HGX | Liberty, Polk, San Jacinto | 30 min |
| Mar 27, 4:37 PM CDT | Severe Thunderstorm Warning | HGX | Harris, Montgomery | 38 min |
| Mar 27, 4:42 PM CDT | Tornado Warning | HGX | Liberty, San Jacinto | 33 min |
| Mar 27, 4:59 PM CDT | Severe Thunderstorm Warning | LCH | Hardin, Tyler | 61 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Lake Charles Mun, LA (KLCH), launched 12:00Z, 4.8 hours before the alert went out and 218 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
- 1993 J/kg
- Mixed-layer CIN
- -20 J/kg
- Mixed-layer LCL
- 509 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- -15 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.2
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 26, 7:32 PM CDT | Severe Thunderstorm Watch | SPC | Cooke, Denton, Fannin, Grayson, Jack, Montague and 1 more | 4 hr |
| Mar 26, 9:13 PM CDT | Mesoscale Discussion | SPC | Angelina, Cherokee, Hardin, Jasper, Jefferson, Nacogdoches and 6 more | 92 min |
| Mar 26, 11:34 PM CDT | Mesoscale Discussion | SPC | Dallam, Hartley, Moore, Oldham, Sherman | 4 hr |
| Mar 27, 2:55 AM CDT | Mesoscale Discussion | SPC | Armstrong, Carson, Dallam, Deaf Smith, Hansford, Hartley and 9 more | 4 hr |
| Mar 27, 8:04 AM CDT | Mesoscale Discussion | SPC | Collingsworth, Donley, Gray, Hemphill, Lipscomb, Ochiltree and 2 more | 4 hr |
| Mar 27, 10:24 AM CDT | Mesoscale Discussion | SPC | Anderson, Angelina, Austin, Bastrop, Bell, Brazoria and 43 more | 96 min |
| Mar 27, 12:30 PM CDT | Mesoscale Discussion | SPC | Carson, Childress, Collingsworth, Donley, Gray, Hansford and 8 more | 6 hr |
| Mar 27, 12:33 PM CDT | Mesoscale Discussion | SPC | Anderson, Bowie, Camp, Cass, Cherokee, Collin and 26 more | 57 min |
| Mar 27, 12:58 PM CDT | Tornado Watch | SPC | Anderson, Angelina, Bowie, Camp, Cass, Cherokee and 28 more | 7 hr |
| Mar 27, 3:34 PM CDT | Mesoscale Discussion | SPC | Anderson, Angelina, Bowie, Camp, Cass, Cherokee and 28 more | 56 min |
| Mar 27, 3:43 PM CDT | Mesoscale Discussion | SPC | Chambers, Hardin, Harris, Jasper, Jefferson, Liberty and 6 more | 62 min |
| Mar 27, 4:49 PM CDT | Tornado Watch | SPC | Brazoria, Chambers, Galveston, Hardin, Harris, Jasper and 6 more | 3 hr |
| Mar 27, 5:53 PM CDT | Mesoscale Discussion | SPC | Bowie, Cass | 97 min |
| Mar 27, 6:35 PM CDT | Tornado Watch | SPC | Angelina, Bowie, Camp, Cass, Cherokee, Gregg and 10 more | 7 hr |
Nearby
Severe Thunderstorm Watches in Texas, 2009Every severe thunderstorm watch 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.