Area Forecast Discussion
Issued by NWS San Angelo, TX
Issued by NWS San Angelo, TX
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225 FXUS64 KSJT 041134 AFDSJT Area Forecast Discussion National Weather Service San Angelo TX 634 AM CDT Sat May 4 2024 ...New AVIATION... .SHORT TERM... (Today and tonight) Issued at 332 AM CDT Sat May 4 2024 ...Severe weather expected again this afternoon and evening... As of 3 AM, a cold front was located just north of Amarillo in the TX panhandle. This will continue to work its way south through the panhandle and into the Big Country around late morning. Ahead of this, southeasterly winds continue to replenish low level moisture despite repeated convective activity over the West Central Texas area the past few days. Our area remains in southwest flow aloft with guidance indicating a shortwave trough ejecting out of the Baja region and into northern Mexico through the day today. In response, mid level flow will increase across the area providing better upper level support. Showers and storms will be possible along and near the frontal boundary as it sags south through the morning hours. As the atmosphere destabilizes significantly by mid-afternoon, this is likely when we will see some robust convective development along/ahead the front and in the warm sector ahead of a dryline in far west Texas. With convective temperatures being met across much of this area by 19-20Z, it won`t take much to get storms to initiate. Instability should be on par with what we have been seeing the past few days with MLCAPE values in the 2500-3500 J/kg range. The notable difference will be the increase in shear (to between 35-45 kts) and mid/upper level support. This increase in shear has lead to an increased tornado potential in conjunction with the continued threat for large to very large hail. Damaging downburst winds will also be possible but are being considered more of a secondary threat at this point, even with DCAPE values well over 1000 J/kg. Initial storms will be supercellular and this is when the the greatest hail and tornado threat will be. By late evening, this activity is expected to grow upscale and develop into an MCS before it travels east/southeast through the area and into Central Texas. Heavy rainfall leading to flash flooding concerns is also expected today with nearly all of West Central Texas in the Slight Risk (Level 2 of 4) for Excessive Rainfall. Given how saturated much of the area is from repeated convective activity over the last week or so, it won`t take much rainfall to create problems in certain areas, especially across the Big Country, Heartland, and NW Hill Country. Precipitable water values are very high areawide in the 1.2-1.7 inch range meaning that storms will be efficient rainfall producers. To recap: Storms are expected to form this afternoon and should quickly become severe. All hazards, including very large hail, potentially strong tornadoes, damaging winds, and flash flooding will be possible. Initially discrete cells will develop into an MCS that will make its way across West Central Texas late this evening and into the overnight hours. Make sure you have your severe weather plans in place on the off chance you haven`t needed to utilize them over the past few days. && .LONG TERM... (Sunday through Friday) Issued at 303 AM CDT Sat May 4 2024 After another afternoon and night of severe weather, main brunt of the convection may be pushing out of West Central Texas by early Sunday morning. Given this slightly faster movement, have lowered POPs a little across the area for the time period starting at sunrise Sunday morning. Some of the CAMs continue to show more convection redeveloping during the afternoon but with the passage of the upper level shortwave having already occurred, not expecting the same type of coverage as we have seen. After that, a drier pattern will return to West Central Texas and allow everyone to have a break from the severe weather. Upper level low over the central plains will continue, helping produce mainly zonal flow across the area for the upcoming week. Will see if any weak shortwaves end up getting embedded which may lead to a small POP for one day, but overall, looks like most areas will be dry for most of the time. Warmer as well, with afternoon highs eventually climbing back well into the 90s once again. && .AVIATION... (12Z TAFS) Issued at 632 AM CDT Sat May 4 2024 VFR to MVFR conditions currently present across the area. High clouds have impeded the progress of the IFR to LIFR ceilings, keeping them further south than previously expected. This means ceilings will likely stay in the VFR to MVFR range for the rest of the day. A cold front is currently moving south through the panhandle and will likely make it to KABI, causing an easterly wind shift, before stalling out. Showers and thunderstorms are expected to develop this afternoon across the area, initially starting out more scattered in nature before merging into a storm complex later this evening. Have updated rain/storm timing with the latest hi-res guidance though this will potentially need to be tailored further going forward. After the rain and storms move out, widespread IFR ceilings are expected to overspread the terminals. && .PRELIMINARY POINT TEMPS/POPS... Abilene 78 61 78 65 / 70 90 20 10 San Angelo 86 62 79 66 / 60 80 40 10 Junction 88 64 81 67 / 40 80 60 10 Brownwood 79 62 77 65 / 40 90 20 20 Sweetwater 77 60 76 66 / 70 90 20 10 Ozona 85 62 78 66 / 40 80 50 10 Brady 81 63 76 66 / 40 90 40 20 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...50 LONG TERM....07 AVIATION...50