FXUS64 KLUB 210534 AFDLUB Area Forecast Discussion National Weather Service Lubbock TX 1234 AM CDT Sun Jun 21 2026 ...New AVIATION... .KEY MESSAGES... Issued at 1233 AM CDT Sun Jun 21 2026 - Very hot Sunday with afternoon highs near or just above 105 degrees. - Low chances for a few storms off the Caprock both Sunday and Monday. - Better chances for evening thunderstorms area-wide continue through most of the upcoming week along with warm temperatures. && .SHORT TERM... (Now through Sunday night) Issued at 1034 PM CDT Sat Jun 20 2026 Ridging over the Desert SW will flatten slightly over the next 24 hours, resulting in a transition to stronger zonal flow aloft over our area to close out the weekend. As this occurs, a surface trough axis stretching from eastern NM into northwest OK will deepen which will in turn allow drier southwesterly surface flow to persist throughout most of Sunday. With flow veering nearly due westerly over much of the Caprock, a dryline will sharpen east of I-27 by afternoon. Weak convergence along the dryline could result in an isolated storm or two over the SE TX Panhandle through mid- evening, but parcels will need to overcome what lingers of a stout subsidence inversion. Approaching weak shortwave energy arriving by sunset may help reduce this inhibition and provide some broader forcing, but storm coverage (if any) will remain isolated with better coverage well to our northeast. The other story for Sunday will be the unseasonably hot temperatures given the relatively strong downslope component to the low level flow and still- elevated layer thicknesses. This will result in highs near 105 degrees over much of the South Plains, with heat indices above 105 off the Caprock in the more humid airmass east of the dryline. A Heat Advisory is therefore in effect for these areas from 1 PM to 9 PM. A very mild and dry overnight period is then expected on Sunday night with the dryline retreating westward ahead of a cold front approaching from the north. && .LONG TERM... (Monday through next Saturday) Issued at 1034 PM CDT Sat Jun 20 2026 By early Monday, the cold front is expected to be positioned over the southern TX Panhandle with a relatively broad surface trough to its south over much of West TX. Model consensus currently favors a relatively slow southward progression of the front on Monday, with southerly flow associated with the above-mentioned surface troughing likely to result in triple digit temperatures once again over our southern zones Monday afternoon. Although surface convergence will intensify near the front and within the surface trough, thunderstorm development Monday afternoon and evening is still uncertain given relatively weak upper level forcing and what will likely be a fairly strong capping inversion. Some models highlight a weak shortwave disturbance approaching from the WNW by Monday afternoon which could support development of some isolated storms Monday evening along the front in the Rolling Plains. Given forecast strong to extreme instability and bulk shear magnitudes over 40 kt, a conditional severe threat will exist with any thunderstorms that are able to develop Monday evening. For the rest of the week, models are in good agreement that the overall synoptic pattern will remain rather consistent with a ~597dam H5 ridge centered somewhere near El Paso for several days. A train of shortwave disturbances within a belt of relatively strong WNW flow aloft will bring at least low chances for thunderstorms moving from the CO/NM high terrain into our area each evening from Tuesday through at least the end of the week, but confidence in this is low with the potential very sensitive to the precise positioning of the ridge. Regardless of precipitation chances, this setup will favor temperatures near or above average for this time of year for the middle and end of the week. && .AVIATION... (06Z TAFS) Issued at 1234 AM CDT Sun Jun 21 2026 VFR with breezy S-SW winds through the day. && .LUB WATCHES/WARNINGS/ADVISORIES... Heat Advisory from 1 PM this afternoon to 9 PM CDT this evening for TXZ023>026-028>044. && $$ SHORT TERM...30 LONG TERM....30 AVIATION...93