Area Forecast Discussion
Issued by NWS
Issued by NWS
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363 FXUS64 KLUB 302318 AFDLUB Area Forecast Discussion National Weather Service Lubbock TX 618 PM CDT Tue Apr 30 2024 ...New AVIATION... .SHORT TERM... (This evening through Wednesday) Issued at 150 PM CDT Tue Apr 30 2024 The dryline is nearing the I27/US87 corridor as of 130 PM and should continue pushing eastward through the afternoon. A CU field is beginning to develop across the Rolling Plains ahead of the dryline where dewpoints are still in the mid to upper 60s. Models continue to show isolated to widely scattered thunderstorms along the dryline by 00Z, but confidence in storms developing within the boundaries of the FA is dropping. Despite CAPE over 1200 J/kg and fairly steep mid- level lapse rates, there is little in the way of upper lift especially while the dryline is over the FA. Timing may line up for a storm or two to develop over our far southeastern counties, but the window of opportunity will be limited with storms more likely to develop once the dryline is east of the FA. If a storm does develop across our southeast, the main severe hazards will be golfball size hail and wind gusts up to 70 mph. Upper flow will become more southwesterly during the overnight hours as the upper trough over the western CONUS amplifies. Surface flow will become more southerly as weak surface low pushes from northeastern New Mexico into the northern Texas Panhandle/Oklahoma Panhandle and the dryline retreats westward. This will allow for excellent surface dewpoint recovery with dewpoints rising back into the upper 40s across our northwest and the upper 60s across our southeast. This will help setup the potential for convection tomorrow afternoon/evening. Models continue to develop convection slightly westward with each run with initiation now being progged along the dryline when it reaches the I27/US87 corridor to slightly just west of there by 00Z. This happens as an upper level shortwave trough moves over the region from northern Mexico. && .LONG TERM... (Wednesday night through next Monday) Issued at 150 PM CDT Tue Apr 30 2024 Convective activity is expected to become more widespread closer to 00Z or just after 00Z tomorrow afternoon. The severe threat will peak around the same time. The same issues that will plague the severe potential today will be similar into tomorrow evening. Continued weak atmospheric flow will keep forcing weak or non- existent. The atmosphere will have to rely on dryline convergence and surface heating for convective initiation. Dry line convergence does not look too impressive with more of a gradual dew point gradient rather than a sharper gradient. Therefore low level winds will depict weak veering along the dryline. Convection is expected to be occurring at 00Z tomorrow afternoon. Surface dew point are expected to remain in the upper 60s across the Rolling Plains by late tomorrow afternoon with strong low level advection of moisture. Strong heating will occur in the Rolling Plains into the upper 80s. Very steep mid-level lapse rates between 8-9 C/km will promote mixed layer instability values in excess of 4000 J/kg. Strong elevated instability will continue to exist after sunset keeping the severe threat going through much of the evening. Weak shear will likely promote multicellular structure to convection with low chances of supercells. Not much training of storms is expected but precipitable water values around 150-175 percent of normal may promote isolated heavy rain/flooding chances. The dryline will race back to New Mexico overnight into early Thursday morning with a drastic change expected from Thursday through the weekend. A cold front will move southward through West Texas during the day on Thursday. This front will bring cloudy and cool conditions on Thursday. Strong low level moisture advection and surface heating ahead of the front will lead to convection along the leading edge of the front and dryline. However, the front may clear the area by late in the afternoon shoving storm chances out of the FA. Cooler than seasonal average conditions will persist through the weekend under easterly low level flow. Although surface conditions will be relatively cool and stable, warm air advection aloft will generate instability aloft and continued chances of thunderstorms, especially on Saturday. A short wave will approach the area on Saturday bringing more widespread rain chances from Saturday evening through Sunday morning. && .AVIATION... (00Z TAFS) Issued at 608 PM CDT Tue Apr 30 2024 Isolated storms this evening will remain south and east of the TAF sites. Winds about 800 ft AGL will increase late tonight leading to LLWS at all sites through around sunrise tomorrow morning. Also around sunrise tomorrow morning a slug of low-level moisture will be working northward towards KLBB and KPVW which may have MFVR to IFR ceilings associated with it. There is currently a 20%-30% chance of low ceilings impacting these sites for a few hours tomorrow morning. Surface winds will increase by late morning with sustained southerly winds around 15kts and gusts to 25 kts. The other concern for tomorrow will be the chance for thunderstorms at the TAF sites towards the end of this TAF period although confidence in timing and location of the storms remains too low at this time to include a prevailing mention. && .LUB WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...51 LONG TERM....01 AVIATION...58