321 FXUS64 KLUB 121104 AFDLUBArea Forecast Discussion National Weather Service Lubbock TX 604 AM CDT Fri Sep 12 2025
...New AVIATION...
.KEY MESSAGES... Updated at 603 AM CDT Fri Sep 12 2025
- Thunderstorms will return this weekend, with heavy rain and flash flooding possible Saturday night to the west of I-27.
- A few storms may be severe Saturday night, with damaging wind gusts possible.
- Storm chances will linger into Sunday, with benign weather heading into next week.
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.SHORT TERM... (Today and tonight) Issued at 1236 AM CDT Fri Sep 12 2025
03Z upper analysis reveals a well-defined cyclone embedded within an amplifying, positively-tilted trough over the Great Basin. This cyclone extends through 200 mb, with the high-level vortex rotating over the Owyhee Mountains. An intense pair of jetlets were rounding its base, with nearly 100 kt at 250 mb translating northeastward across the Great Basin atop a belt of 40 kt flow at 500 mb. Farther east, the mid-level center of the subtropical ridge was rotating over central N TX. This ridge will continue progress eastward into the Mississippi Alluvial Plain throughout the next 24 hours, as the concavity of the incoming trough increases as it begins to emerge over the Intermountain West.
The surface pattern remains relatively similar to Thursday, with a diffuse trough bisecting through the CWA based on WTM data. However, winds will become breezier Friday afternoon due to the strengthening isallobaric response associated with cyclogenesis in eastern CO, as the leading edge of the jetlets will begin to nose into the High Plains region and induce greater pressure falls. Vertical mixing heights will ascend to near 700 mb by peak heating, although high temperatures will be a couple of degrees cooler than the past few days. Highs will range from the upper 80s near the NM state line and into the middle 90s in the Rolling Plains. Breezy conditions are expected to last into the overnight hours, resulting in slightly warmer low temperatures beneath increasing cirrostratus.
Sincavage
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.LONG TERM... (Saturday through Thursday) Issued at 1236 AM CDT Fri Sep 12 2025
The shortwave trough to the west will be neutrally-tilted Saturday, with the closed low also eroding and eventually opening as it rotates east of the Great Basin. At the surface, the large-scale, isallobaric response will intensify; and a stiff, southerly breeze expected by Saturday afternoon, with winds between 15-20 mph across the entire CWA. Winds will gradually back to the southeast towards the evening hours from ongoing cyclogenesis to the northwest of the CWA and as the leading shortwave perturbation ejects into the Great Plains. Moist, isentropic ascent will be vigorous as the monsoonal plume gradually shifts eastward towards the CWA, and it appears that the bulk of the moist ascent will arrive during the late-afternoon and evening hours as the trough becomes negatively-tilted. NBM PoPs were removed for the morning hours Saturday through 18Z/1 PM CDT, and trimmed to the west of the I-27 corridor for the afternoon.
Storm chances are set to increase quickly Saturday evening as the monsoonal plume shifts eastward and as the Pacific cold front nears the Mescalero Escarpment. Steering flow will be oriented towards the southwest at around 30 kt, with a corridor of impressive IVT values nearing 400 kg/m/s advecting near the NM state line Saturday night into Sunday morning, along with PWATs exceeding the 99th percentile late Saturday night within the monsoonal plume. Frontal-parallel Corfidi vectors will favor the potential for training storms, especially to the west of the I-27 corridor, which is where the greatest concentration of storms will be before the low-level jet veers. Storm chances will lessen with eastward extent into the Rolling Plains during the nighttime hours Saturday into Sunday morning, as NWP guidance is in considerable agreement on a narrow channel of monsoonal moisture evolving with this system given its quick progression and modulation into a negatively-tilted trough as it pivots into the central Great Plains by Sunday morning. However, a couple of swaths of locally heavy rainfall will be possible into the Rolling Plains through the predawn hours Sunday. To the west of the I-27 corridor, it appears that several swaths of heavy rainfall will be possible through Sunday morning, especially for locales near the NM state line in closer proximity to the Pacific cold front.
Negatively-tilted troughs typically have a fast progression when ejecting into the Great Plains, and the base of the trough is forecast to pivot from the Mogollon Rim to the NE Sandhills within 24 hours (Saturday night to Sunday night). Isentropic descent will be advecting over the region Sunday, but with the Pacific front gradually weakening, a few lingering storms will be possible across portions of the CWA Sunday. NBM PoPs were lowered to 20-percent (or a slight chance) for Sunday afternoon, as increasingly confluent flow aloft on the backside of the attenuating trough atop the convectively-overturned airmass will keep coverage widely-scattered at best. Thereafter, restoration of a low-amplitude, subtropical ridge will govern benign weather through the early and middle part of next week. Global NWP guidance continues to converge on the placement of the development of a weakly cyclonic gyre over the northern Rocky Mountains, which will keep the CWA bereft of any shortwave troughing until at least the end of next week.
Sincavage
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.AVIATION... (12Z TAFS) Issued at 603 AM CDT Fri Sep 12 2025
VFR is expected through the TAF period with a very small chance of low CIGS early Saturday morning.
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.LUB WATCHES/WARNINGS/ADVISORIES... None. &&
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SHORT TERM...09 LONG TERM....09 AVIATION...01
NWS LUB Office Area Forecast Discussion