textproduct: Lubbock

KEY MESSAGES

Updated at 1217 PM CDT Sun Sep 20 2026

- Isolated to scattered storms are expected this afternoon and evening, primarily off the Caprock. Storms will be capable of producing strong to severe wind gusts.

- Much cooler this week, with daily chances for showers and storms. The precipitation chances are generally higher on the Caprock than off the Caprock.

SHORT TERM

(This evening through Monday) Issued at 1217 PM CDT Sun Sep 20 2026

At the start of the period, an upper low was positioned over Wyoming. A weak front was evident across the far southern TX Panhandle as of 17z/Noon. This front is expected to slowly sag south today, perhaps aiding storm development in an otherwise weak forcing regime. Forecast soundings exhibit the typical deep PBL/high DCAPE signature that we have become accustomed to in recent weeks, supporting potential for strong to severe gusts with any storms that do form. Deep layer shear is rather meager across our area (around 20 kts), so storm organization will be limited, and outflows will be a primary driver of the convective evolution once again. Given the weak forcing, there remains some uncertainty on the placement/coverage of storms, but most CAMs tend to favor the Rolling Plains and far eastern South Plains (10-30% coverage). Today should offer one more hot day before a noticeable cool down during the coming week. Temps were in the 80s as of this writing (17z/Noon), but should rise into the 90s across most of the FA this afternoon.

Moist, easterly upslope flow on Monday is expected to aid additional storm development near the TX/NM border Mon PM. With sfc dewpoints in the low to mid 60s, forecast soundings show moderate instability with mixed-layer CAPE (MLCAPE) approaching or exceeding 1500 J/kg. Lower cloud bases limit the DCAPE, with values closer to 900 J/kg compared to the 1500+ J/kg that has been commonplace lately, which should limit the damaging wind threat. Forecast hodographs are straight and relatively long, which suggests potential for isolated large hail, however, meager mid-level lapse rates may be a limiting factor. The storm chances on Monday are initially highest across the Caprock (20-30%) before spreading east during the late evening. The cooling trend begins Monday, with highs generally forecast to be in the 80s on the Caprock, with upper 80s and low 90s off the Caprock. Since July 18th, the Lubbock Airport has had just one day with a high temp below 90 degrees (which occurred last Wednesday, Sept 16).

LONG TERM

(Monday night through next Saturday) Issued at 1217 PM CDT Sun Sep 20 2026

The key takeaway of the long term forecast is an unsettled week, with frequent precip chances, increased cloud cover, and cooler temps. For Tues/Wed, the upper pattern will be characterized by a weaker upper ridge axis located to our east, extending from E TX northward onto the east-central Great Plains, and an upper low lifting from NV to the northern Plains. Additional lift will be provided by a disturbance embedded within the SSW flow regime across NM.

Locally, this translates to several days of continued moist, easterly upslope flow. Forecast soundings again show lower cloud bases compared to recent weeks, with uninspiring lapse rates aloft keeping instability values in check, thus the severe potential with any storms on Tues-Wed appears quite limited. While there remains some uncertainty on the exact placement of storms Tues- Wed, the general theme is that precip chances and forecast rainfall amounts increase with westward extent (and are highest across eastern New Mexico). For example, the NBM probability of exceeding 2" of rain between Tues AM and Thurs AM is greater than 50% along the TX/NM border, but decreases sharply to just 15-20% along the I-27 corridor, and less than 10% off the Caprock. This expectation is captured in the Excessive Rainfall Outlooks, which keep the Slight Risk (level 2 out of 4) of flash flooding confined to our western FA on Tues-Wed.

The nocturnal onset of the low-level inversion should trap moisture and keep cloud cover prevalent Tues/Wed night, and I do wonder if this will lead to low temps staying a bit warmer than the NBM suggests. At any rate, lows in the 60s and perhaps upper 50s will be much closer to seasonable values than the conditions that have been in place over the last several weeks. On the flip side, all the clouds cover and potential precip should keep highs much cooler, with much of the Caprock forecast to see highs in the upper 70s, roughly 15 degrees cooler than what is forecast for today. The mid- week disturbance starts to lift north late in the week, but guidance suggests there will be enough forcing to keep precip chances in place locally for Thurs-Fri. As we head into next weekend, the precip chances do trend lower (and temperatures trend warmer) as a subdued ridge axis shifts back west over the FA.

AVIATION

(18Z TAFS) Issued at 1217 PM CDT Sun Sep 20 2026

Isolated to widely scattered storms are possible late this afternoon in the vicinity of the KCDS terminal but confidence is low in the occurrence of these storms. A cold front will slowly push into the region during the evening and overnight hours shifting winds to the east to northeast. Low CIGS may follow after sunrise on Monday morning with highest chances at KCDS.

LUB WATCHES/WARNINGS/ADVISORIES

None.