dangerous and advised that proper tornado safety measures be taken. A call was made to the Reeves County Sheriff's Department in Pecos at 7:55 p.m. advising the department of the tornado warning.

The county's Emergency Operating Center (EOC) at Pecos was activated by the emergency management coordinator around 8:00 p.m. after receipt of the tornado warning. The EOC is activated for tornado warnings but not normally for severe thunderstorm or flash flood warnings.

The two tornado reports logged in the NWS Midland's severe weather logs came from storm spotters and from the Pecos DPS. The logs show some confusion in the communication of reports since one report was for the area 4 miles west of Balmorhea and the other was for the area 4 miles east of Balmorhea. The DPS report came from a public safety officer who was filling up his vehicle 's gas tank at a bulk gas plant at the 210-mile marker on Interstate 10.

Following the initial warnings and reports of the tornado, the NWS issued a severe weather statement at 8:20 p.m. headlining the tornado warning for south-central Reeves County. The statement described the tornado report and noted movement to the east at 30 mph. Another severe weather statement issued at 8:30 p.m. again highlighted the tornado warning. It stated that a tornado was reported at a local school. A third severe weather statement at 8:40 p.m. continued to headline the tornado warning and again reported substantial damage in Saragosa.

A new report of a funnel cloud 28 miles west of Fort Stockton from the Reeves County Sheriff's Department prompted an NWS tornado warning at 9:04 p.m. valid until 10:00 p.m., for southern Reeves and western Pecos counties. The warning noted that this was the same storm that had produced fatalities in Saragosa. The NWS Midland office issued several more warnings and statements throughout Friday night. (See Appendix E for a chronology of severe storm warning releases.)

NOTES

1. The LI refers to a relative measure of instability in the atmosphere expressed as a numerical value. It is arrived at by lifting a parcel of air dry adiabatically to its point of saturation and then along the moist adiabat to some reference pressure level such as 500 or 300 millibars. At that reference level, the temperature of the lifted parcel is compared to the ambient air temperature to arrive at an index value.

The adiabatic process refers to the thermodynamic change of state of a system in which there is no transfer of heat or mass across the boundaries of the system. A specific lapse rate (i.e., the rate of decrease of temperature with height for a specific air parcel) is associated with the assumption of a dry or saturated condition of the air parcel.

2. “Prog” refers to a 24-hour forecast chart of projected lifted indexes.

3. The West Texas Forecast Discussion is a message prepared four times daily



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