On the afternoon of the 28th, scattered thunderstorms developed off of the Sacramento Mountains of New Mexico under moist, upslope flow. By the evening, these storms had developed into a squall line that moved across the central and southwestern South Plains.
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The episode as NWS LUB wrote it up.
On the afternoon of the 28th, scattered thunderstorms developed off of the Sacramento Mountains of New Mexico under moist, upslope flow. By the evening, these storms had developed into a squall line that moved across the central and southwestern South Plains. A couple of severe wind gusts were reported from this squall line as it moved through the southwestern South Plains. Well behind the squall line in the stratiform precipitation region, a wake low produced a high wind gust near Morton (Cochran County) to 60 mph measured by the Texas Tech University West Texas mesonet.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Lubbock, TX wrote its last area forecast discussion before the first event at May 28, 6:10 PM CST, 2 hours 10 minutes earlier.
Area Forecast Discussion National Weather Service Lubbock TX 710 PM CDT Fri May 28 2021 .AVIATION... Watching a cluster of thunderstorms in eastern New Mexico slowly move to the east. Confidence still remains low as to whether or not this activity will reach KLBB or KPVW tonight. If it does hold together than this activity would impact those terminals around 04z. Low ceilings will most likely return once again late tonight into early Saturday morning with indications that these will hover right around the MVFR/IFR height. Ceilings will gradually improve late tomorrow morning with VFR conditions expected thereafter. && .PREV DISCUSSION... /issued 225 PM CDT Fri May 28 2021/ SHORT TERM... The big wrench thrown into the forecast today will be any remnant outflow boundaries and front or fronts. The main quasi-stationary front is well south of the region early this afternoon. This front is expected to be the focus for the most intense convection of the day in the Permian Basin and Big Country. Another weaker boundary/front moved through earlier this morning and even another boundary was currently moving southward through the southern South Plains and southern Rolling Plains. Therefore, most convection has been and will likely continue to be elevated through the evening. A weak short wave seen on water vapor imagery, and to some extent in models, was approaching the area across New Mexico this afternoon. Combined with the upslope low level low, convection has already begun in the Sacramento mountains of New Mexico. Nearly straight line winds at 250mb will bring some broad and weak upper level divergence overhead today. An area of higher theta-e air was concentrated south of the main front in the Permian Basin. However, a ridge of higher theta-e air extended northward into eastern New Mexico. This will result in a very unstable air mass in this region with MU CAPE values on the order of 2500-3000 J/kg near the Texas/New Mexico state line. These instability values will decease the farther east you travel into the South Plains. These instability values along with fairly strong deep layer shear around 40-45kt will support severe storms if updrafts can be sustained this far off of the higher terrain of eastern New Mexico. Timing on these storms is expected to be around mid-evening to reach the western and southwestern South Plains. They will primarily have the potential to produce large hail early on but likely transition to more of a wind threat by late evening. For Saturday, short wave ridging and rising heights will most likely shut down convection for the South Plains. Additional development off the mountains of New Mexico is likely but chances of these storms making the South Plains is low. LONG TERM... Saturday night into Sunday, the shortwave ridge axis which provided a brief reduction in precipitation chances during the day on Saturday will shift east of the area. Mid to upper southwesterly flow will quickly re-establish over West Texas as a digging 500mb trough sweeps over southern Arizona on Sunday afternoon. Guidance continues to indicate that this southern trough will phase with another shortwave over south-central Canada, which should allow the southern trough axis to retain a positive tilt as it slides eastward. Ahead of this trough, low level flow will remain southeasterly as broad surface ridging remains parked over the Ohio Valley. Consequently, moisture will continue to stream into the area on Sunday, with PWATs possibly approaching 1.3" (near the 90th percentile of climatological values) and surface dewpoints reaching the mid 60s across the CWA. As the upper trough axis moves eastward on Sunday, a surface trough will begin to deepen in the lee of the Rockies, and is progged to be centered somewhere in the vicinity of the southern CO/KS border, possibly further south into the OK Panhandle by Sunday evening. As this occurs, a surface boundary will take shape and provide the necessary convergence for convection to initiate. With ample upper level support from 500mb height falls as well as an approaching upper jet streak, a robust area of convection should develop in the TX/OK Panhandles Sunday night and shift southward along the boundary overnight into Monday morning. Given the magnitude of the moisture present along with the amplifying effects of a strengthening low level jet overnight, heavy rain and flooding will certainly be a concern with this activity. Flooding concerns may also be elevated due to slow storm motion and saturated ground from prior convection. WPC has placed much of our area in a Slight Risk for excessive rainfall Sunday into Monday, echoing these concerns. The daytime hours on Monday also have the potential to be quite wet, with additional rounds of heavy rain and convection possible as residual boundaries linger around the CWA and the upper trough remains to our west. Severe weather is also possible, as CAPE looks to exceed 2000 J/kg and bulk shear looks to be around 40 kt. The evolution of convection/heavy rain/severe weather will depend heavily on the placement of boundaries and mesoscale features. While these influences cannot be precisely resolved this far in advance, confidence remains high that Sunday night into Monday will be an extended period with impactful weather. Stay tuned as the forecast is refined during the coming days. Monday night into Tuesday, the axis heaviest rain will likely shift to the southeast, although residual thunderstorms are possible across the entire CWA on Tuesday and Wednesday as the upper trough axis moves overhead. Temperatures will remain seasonally cool through the middle of the week as well. By Thursday, the main trough axis will be east of the area. However, broad cyclonic upper flow will still be present over the southwestern CONUS and northern Mexico. This combined with continued low level southerly to southeasterly flow and subsequent moisture advection will result in thunderstorm chances each afternoon through the end of the long term period. /DWK && .LUB WATCHES/WARNINGS/ADVISORIES... None. && 58/01/30
Hazardous Weather Outlook National Weather Service Lubbock TX 751 PM CDT Fri May 28 2021 TXZ021>044-300100- Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-Floyd- Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-Yoakum- Terry-Lynn-Garza-Kent-Stonewall- 751 PM CDT Fri May 28 2021 This Hazardous Weather Outlook is for the South Plains, Rolling Plains and the far Southern Texas Panhandle. .DAY ONE...Tonight. Scattered thunderstorms, some severe, will be possible this evening across the western and central South Plains. Storms that do form will have the potential to produce large hail up to two inches in diameter and wind gusts to 75 mph. Also, heavy rain may lead to localized flooding. .DAYS TWO THROUGH SEVEN...Saturday through Thursday. Thunderstorm chances Saturday afternoon and evening will be small and confined to areas near the New Mexico state line. There is a marginal risk that these storms could become severe. More widespread showers and thunderstorms are expected Sunday and Monday and will bring the potential for heavy rain and severe weather. Thunderstorm chances will persist Tuesday and Wednesday and may again bring a risk for severe weather. .SPOTTER INFORMATION STATEMENT... Spotter activation will be needed.
The Lubbock radar (KLBB), 106 km away, was scanning. The volume nearest the first event began at 02:17 UTC.
2 thunderstorm wind, 1 high wind. Local standard time, as filed.
A Texas Tech University West Texas mesonet site near Plains measured a wind gust to 58 mph.
Emergency management in Hockley County reported that a power pole was blown over at the intersection of Mexico Road and US Highway 385 just south of Whitharral.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2021Every state in 2021This day in weather historyWarnings in Texas, May 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 953245, 953248, 953246.