Area Forecast Discussion
Issued by NWS
Issued by NWS
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052 FXUS64 KLUB 021910 AFDLUB Area Forecast Discussion National Weather Service Lubbock TX Issued by National Weather Service Amarillo TX 210 PM CDT Thu May 2 2024 ...New SHORT TERM, LONG TERM... .SHORT TERM... (This evening through Friday) Issued at 205 PM CDT Thu May 2 2024 A cold front, oriented in an arcing fashion from southwest to northeast, has moved through the western portion of the area and is moving through the northeastern counties as of 2 PM. Meanwhile, clouds have mostly cleared out ahead of the cold front where there is relatively rich low-level moisture. Anticipating that a very gradual low-level moisture gradient in the southern CWA will begin to tighten through the afternoon into a dryline, and thunderstorms are favored to develop in the mid to late afternoon. The primary uncertainty is regarding where the dryline will be when thunderstorms begin to develop, and where exactly they will develop. The chance for thunderstorms today is focused on the southeast, but it is possible that thunderstorms develop just south or east of the CWA. Regardless, with sufficient low-level moisture in place and steep lapse rates, MLCAPE will climb to around 1500-2500 J/kg, possibly slightly higher, in the southeast along with effective shear values around 40-50 kts. This suggests thunderstorms would become supercellular, and due to a relatively straight hodograph, a splitting supercell may occur initially. Very large hail and damaging winds would be the primary threats. A tornado can`t be ruled out, but would be more favored south or east of Stonewall county. Again, this is conditional upon thunderstorms being able to develop in the CWA and being able to mature enough prior to moving out of the area. Low-level moisture moves in with upsloping easterly winds which favors the development of fog in the east and north, possibly with some drizzle. Can`t entirely rule out some elevated convection, but there is low confidence in that at this time. Tomorrow, winds turn southeasterly ahead of another weak shortwave trough and moisture is brought back in. Mid to upper-level support for ascent looks rather modest at best, but a dryline is favored to push east in the mid to late afternoon which may help focus ascent and develop convection along the boundary. That said, if morning clouds linger and/or the cap is slightly too strong, then thunderstorms may struggle to develop. If thunderstorms can develop, forecast thermodynamic profiles look somewhat similar to today, but shear looks slightly weaker. Regardless, all hazards would be possible with hail possibly exceeding 2 inches in diameter. This may linger into a portion of the evening before weakening due to a loss of daytime heating. Vanden Bosch && .LONG TERM... (Friday night through next Wednesday) Issued at 205 PM CDT Thu May 2 2024 SUMMARY...A wet and stormy start to the weekend is in store for much of the area. On top of a low-end threat for severe storms on Saturday, eastern portions of the area appear favored to receive localized areas of substantial rainfall through Sunday morning. After a cooler weekend, warm temperatures look to quickly rebound next week as moisture exits the region. DISCUSSION...Model indications continue to suggest strong to severe storms may develop Saturday along and ahead of an approaching shortwave disturbance within southwest flow aloft. Placement of a cold front slated to advance southward through the morning hours, before eventually stalling out, may ultimately dictate where this threat will occur. Increasing east-southeasterly sfc flow ahead of the front should aid in strong moisture return Saturday, allowing for moderate destabilization by the afternoon hours with modest daytime heating. Model forecast soundings depict steep mid-level lapse rates in the presence of aforementioned instability and adequate deep-layer shear, suggesting large hail and strong winds would be the primary hazards in strongest storms. It appears however, that extended periods of heavy rainfall may be the more prominent element this weekend. Rich theta-e advection to the area combined with persistent enhanced lift along the remnant boundary should help to generate widespread showers and storms through Sunday morning. With anomalously high PWATs over 1.00-1.50" and favorable large scale ascent expected to be in place, higher rain amounts are certainly on the table, especially for areas off the Caprock towards the Big Country. Here, deterministic and ensemble guidance signal medium to high probabilities (50-80%) for rainfall totals to exceed 1 inch before convection pushes eastward through the day Sunday. Model guidance agrees a far more pronounced upper low lifts into the Great Plains on Monday, but will track too far north, generally leaving moist of the CWA high and dry. Can`t entirely rule out some stray convection across the far eastern counties Monday afternoon, but chances are <20% at this time. In this system`s wake, zonal flow aloft and rising 850mb temps are progged to initiate a warming trend, with highs in the 80s to low 90s along with breezy winds through midweek. Harrel && .AVIATION... (18Z TAFS) Issued at 1245 PM CDT Thu May 2 2024 MVFR ceilings are present at Childress and should clear out further to VFR this afternoon. MVFR ceilings return tonight for all sites along with some visibility restrictions. IFR ceilings are possible tonight, but confidence at this range is too low to include in the TAFs at this time. && .LUB WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...99 LONG TERM....99 AVIATION...99