Area Forecast Discussion
Issued by NWS
Issued by NWS
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205 FXUS64 KLUB 301127 AFDLUB Area Forecast Discussion National Weather Service Lubbock TX 627 AM CDT Tue Apr 30 2024 ...New AVIATION... .SHORT TERM... (Today and tonight) Issued at 329 AM CDT Tue Apr 30 2024 Weak zonal flow will persist aloft today and tonight. Southerly surface flow will help to bring low level moisture into the far southeast Texas Panhandle, southeast South Plains and Rolling Plains this morning with dewpoints in the upper 50s to lower 60s. Lee cyclogenesis will develop this afternoon across northeast New Mexico with a sharpening of the dryline. Warm downsloping winds will give way to above normal temperatures in the upper 80s to lower 90s. Lubbock will approach, but may fall a few degrees short, of a record breaking high today of 94 degrees (set back in 2013). Model inconsistencies remain on where the dryline will officially be by the time convective temperatures are breached this afternoon. Isolated thunderstorm development is possible along and east of the dryline. Best chances for a storm or two to initiate will be across the far southeastern South Plains and southern Rolling Plains with weak convergence along the dryline. Modest instability with MLCAPE values around 1500-2500 J/kg and shear around 20 to 30 knots will support a strong to marginally severe thunderstorm. Primary threat will be large hail with steep midlevel lapse rates. However, a strong to damaging wind gust cannot be ruled out. With weak steering flow aloft, storms that develop will be slower moving with a potential for localized heavy rainfall and flooding. Temperatures tonight will remain above normal and mild in the upper 50s to mid 60s with another surge of low level moisture and dewpoints in the lower 60s across much of the area. There is a potential for a record breaking warmest minimum temperature early tomorrow morning at Lubbock with the previous record being 66 degrees (set back in 2020). && .LONG TERM... (Wednesday through Monday) Issued at 329 AM CDT Tue Apr 30 2024 Flow aloft will gradually back towards a more southwesterly direction through the day on Wednesday as broad upper troughing overspreads the western CONUS. Impressive low level moisture will already be present across the region with dewpoints progged to reach well into the 60s along and east of I-27 during the morning hours. Weak surface troughing over northeast NM will sharpen a dryline roughly in line with I-27/US-87 by early afternoon with impressive MUCAPE values in excess of 3000 J/kg east of the dryline. Upper level forcing for ascent will still be fairly weak with little in the way of midlevel PVA or jet level flow. However, convective temperatures should be reached by mid-late afternoon, and this combined with modest low level convergence along the dryline should still support scattered thunderstorm development near or just east of the I-27 corridor during the late afternoon hours. Despite the robust instability present, given the weak flow aloft, deep layer shear is expected to remain modest with effective magnitudes only peaking near or just above 30 kt. Given the very unstable moist sector, this should still be enough to support a few supercells capable of all hazards through the evening hours, but at this time large hail appears to be the primary hazard. Storms may evolve into a loosely organized cluster over the Rolling Plains before exiting to the east early Thursday morning, with locally heavy rainfall possible given PWATs well above one inch. A weak cold front will pass southward through the region Thursday morning, with most guidance placing the front south of our area and best moisture to our east by Thursday afternoon. This scenario would result in a mainly dry day across the forecast area on Thursday, but additional storms would be possible if the front positions further north over the Rolling Plains. This still looks unlikely though, so will keep PoPs sub-mentionable across most of the region on Thursday with the exception of the eastern Rolling Plains. Friday is currently also expected to remain mainly dry, although some solutions do develop a few showers and storms within weak upslope surface flow. Current thinking is that precipitation will be generally sparse on Friday given a lack of any focusing mechanism at the surface and continuing weak flow aloft, but given the rich low level moisture in place a few isolated storms will be possible over the Rolling Plains Friday afternoon. More widespread showers and storms still look possible on Saturday and Sunday as a more well-defined disturbance within the southwest flow aloft transits overhead at the same time a secondary cold front passes through the region. Will keep PoPs fairly broad- brushed through the weekend given timing differences between models, but ensemble consensus does point to a respectable potential for measurable precipitation across most of the forecast area this weekend with drier conditions returning early next week. && .AVIATION... (12Z TAFS) Issued at 624 AM CDT Tue Apr 30 2024 VFR conditions are expected to prevail through the period at all three TAF sites. Low level wind shear around 800 feet out of the southwest at 40 knots this morning with the increased low level jet. Southwest surface winds will pick up this afternoon at all three sites around 15 to 20 knots with higher gusts up to 30 knots possible. Isolated thunderstorms this afternoon and evening are expected to remain east of all the sites. The low level jet will once again ramp up tonight with the potential return of low level wind shear at all three sites. && .LUB WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...11 LONG TERM....30 AVIATION...11