Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/27/22

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
636 PM CDT Fri Aug 26 2022 ...New AVIATION... .SHORT TERM... (This evening through Saturday Night) Issued at 209 PM CDT Fri Aug 26 2022 Due to the combination between the sagging stationary front and the seabreeze, showers and thunderstorms are ongoing across the CWA this afternoon. Biggest impacts are heavy rain, frequent lightning, and gusty winds. Currently, there are no warnings or statements issued. However, since PWATs are forecast to be above our seasonal average, heavy rain will lead to nuisance flooding and even possibly flash flooding west of I-69C where rain occurred this morning especially near the city of Zapata where a flash flood warning was issued. The HRRR has most of the activity dissipating near sunset this evening. Low temperatures tonight will be in the mid 70s with partly cloudy skies. Tomorrow, as the low pressure system over Louisiana begins to push to the east, our rain chances decrease. Have only about 20 percent POPs for tomorrow with most of the rain likely coming from the seabreeze in the afternoon. Temperatures will be in the upper 90s tomorrow with mostly sunny skies. && .LONG TERM... (Sunday night through next Thursday) Issued at 209 PM CDT Fri Aug 26 2022 As we head into our climatological favored time of the year for rainfall, models continue to show our atmospheric conditions favoring isolated to scattered daily convection through the long-term period. Mid-level troughing (GFS strongest) over the western Gulf of Mexico approaches NE Mexico and Deep S TX Sunday moving over and west of the region Monday. This mid-level weakness remains embedded within the mean 500mb ridge hovering over South Texas through at least the middle of next week. Deterministic models and ensemble means from the latest GEFS and 00Z ECENS show pwats surging back over 2 inches near the coast Sunday and further west Monday. The high moisture content retreats back to the coast for Tuesday but overall pwats remain elevated in the 1.8 to 2.1 inch range Tuesday-Thursday. Pops continue to show some day to day and model to model variations but should remain generally in the 20 to 40 percent range. Temperature trends look consistent and will continue to lean with persistence with no extremes with weak ridging and the daily chance for rain. Highs range from the upper 80s at the local beaches to mid to upper 90s inland to around 100 degrees out west. Lows to range near seasonal averages 75 to 80 degrees. As for the tropical outlook, yes the GFS looks ominous but this particular model is the only one indicating any type of tropical development from the Central Caribbean tropical wave. The NHC continues to track this weak system, currently showing limited convection associated with it, which has only a 20 percent chance of tropical development in the next 5 days. WFO BRO and the National Hurricane Center will continue to monitor this system for any future development. && .AVIATION... (00Z TAFS) Issued at 636 PM CDT Fri Aug 26 2022 VFR should continue to prevail through the forecast period with light to moderate southeast winds. Shower activity will decrease through the rest of the evening, with mostly dry weather by sunset. Shower/thunderstorm activity isn`t expected to be as active on Saturday, but cannot completely rule out a stray shower/storm through the afternoon. However, not enough confidence and coverage to include in any of the TAFs for now. && .MARINE... Issued at 209 PM CDT Fri Aug 26 2022 Tonight through Saturday Night: Isolated to scattered showers and thunderstorms are possible through the Short Term period with frequent lightning, heavy downpours, and gusty winds being the main threat. Seas will increase slightly this weekend and will be around 2 to 3 feet. Sunday through Tuesday: Daily (day and nighttime) Showers and thunderstorms are expected to be isolated to scattered through the forecast period. Occasional scattered to numerous activity Sunday night through Monday is possible with a mid-level low pressure trough passing overhead. Any showers and especially thunderstorms will exhibit higher wind and produce rough seas along with lightning and torrential rainfall. Otherwise, Seasonal light to moderate onshore flow and slight seas can be expected. Periods of higher wind and seas are likely during persistent thunderstorm activity. && .PRELIMINARY POINT TEMPS/POPS... BROWNSVILLE 94 79 97 80 / 90 10 20 20 HARLINGEN 94 77 97 77 / 90 10 20 10 MCALLEN 98 77 98 78 / 70 20 20 0 RIO GRANDE CITY 98 78 98 78 / 70 20 10 0 SOUTH PADRE ISLAND 87 80 88 80 / 100 10 10 20 BAYVIEW/PORT ISABEL 90 78 90 78 / 90 10 10 10 && .BRO WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...65-Soria LONG TERM...59-GB AVIATION...67-Mejia
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
621 PM CDT Fri Aug 26 2022 ...New AVIATION... .SHORT TERM... (Tonight through Saturday night) Issued at 153 PM CDT Fri Aug 26 2022 Mesoanalysis: 18Z observational data shows the continued persistence of a weak stationary boundary across portions of the area. Best defined across the east, the front roughly parallels Interstate 10 from Houston to Gonzales to San Antonio. Scattered convection has been observed in spots along this corridor over the last 60 minutes, particularly in the Coastal Plains where the highest precipitable water values continue to reside. The front rapidly begins to lose definition to the west of the San Antonio metro, where winds have gone largely calm. An additional zone of weak surface convergence was analyzed between Fredericksburg and Kerrville, extending north into San Saba County. Transient showers have developed along this boundary at times late this morning/early afternoon, but have been quick to dissipate in a comparatively drier air mass. The surface boundaries, particularly the stationary front, will wash out as forecast moving through tonight and tomorrow morning. This Afternoon: Showers and thunderstorms will continue to increase in coverage along the remnants of the stationary boundary. While scattered in nature, cells will be capable of producing locally heavy rainfall, especially along/south of Interstate 10 to the east of San Antonio where radar has estimated rainfall rates of 1-2 inches per hour with the early afternoon activity. Thus wouldn`t be surprised if a few locations pick up a quick 1-2 inches of new rainfall between now and sunset, though said totals won`t be widespread. Expect rainfall amounts in the 0.1-0.5 inch range to be much more common in spots experiencing storms. Activity will decay rapidly following sunset and the loss of surface heating. Temperatures should top out in the upper 80s to low 90s areawide, with the coolest spots being found in Hill Country. Tonight: Temps in the low to mid 70s are forecast areawide. Weather will be quiet, however, recent HRRR runs have hinted at some low cloud cover and/or ground fog across portions of Hill Country and the Southern Edwards Plateau near daybreak. With forecast soundings sampled across the region depicting saturation and nearly calm winds in the near-surface layer, this scenario doesn`t seem implausible. Tend to think any coverage will be confined to isolated low spots, and thus haven`t carried any mention of this in the forecast grids. Any low cloud cover/ground fog that develops will quickly burn off following sunrise. Tomorrow-Tomorrow Night: Model guidance continues to hint at the potential for isolated thundershowers during the afternoon hours across portions of the CWA. With today`s front being washed out, forcing will be limited to the sea breeze and realization of convective temperatures, thus leading to overall lower PoPs in tomorrow afternoon`s forecast. Greatest potential for a passing storm will be to the east of I-35 and south of I-10, where deeper moisture and the sea breeze will be collocated with one another. Like today, activity will rapidly diminish as the surface begins to cool following sunset. Low-mid 70s are forecasted once again tomorrow night. && .LONG TERM... (Sunday through Friday) Issued at 153 PM CDT Fri Aug 26 2022 On Sunday, only expect some isolated to scattered showers and storms mainly east of the I35 corridor where the best moisture is expected to be located. Moisture levels will increase on Monday as a trough axis moves northeast into the area off the Gulf of Mexico. There will likely not be any surface feature for storms to remain rooted to, but with expected increase and moisture and upper low, expect PoPs to increase on Monday and peak out in the 50-60 percent range on Tuesday. This feature will likely be slow to move so expect those elevated PoPs to hang around into the Wednesday before slightly decreasing on Thursday. While it is too early to get into specifics on rain amounts and locations, am not expecting that widespread heavy rainfall event without the surface focus, but other mesoscale features could develop next week and with elevated moisture will have to keep a close eye on things. The moisture and rain chances will keep high temperatures in the lower to middle 90s for the most part, but some 80s can be expected once again where rain becomes more prolonged. August looks to continue its trend of doing its best to look completely different than July and September may start that way as well. && .AVIATION... (00Z TAFS) Issued at 621 PM CDT Fri Aug 26 2022 VFR conditions are expected through the period with primarily light and southerly to southeasterly winds. A FEW to SCT cloud deck around FL015-020 may develop late tonight into early tomorrow morning at the I-35 terminals, but confidence in MVFR cigs developing is not high at this time. A few isolated showers and thunderstorms may also be present near the I-35 terminals tomorrow afternoon, but to due the forecasted limited coverage we will hold off on VCSH/VCTS mention for now. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 75 96 76 97 / 10 20 10 20 Austin Bergstrom Intl Airport 74 94 76 96 / 10 20 10 20 New Braunfels Muni Airport 75 94 76 97 / 20 20 10 20 Burnet Muni Airport 73 94 74 95 / 10 20 10 10 Del Rio Intl Airport 77 97 77 97 / 10 10 10 10 Georgetown Muni Airport 75 94 76 96 / 10 20 10 20 Hondo Muni Airport 75 94 76 95 / 20 20 10 10 San Marcos Muni Airport 74 95 74 97 / 20 20 10 20 La Grange - Fayette Regional 75 94 74 95 / 20 20 0 30 San Antonio Intl Airport 75 94 76 94 / 20 20 10 10 Stinson Muni Airport 75 95 77 96 / 20 20 10 20 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...Quigley Long-Term...29 Aviation...Gale
Area Forecast Discussion
National Weather Service Lake Charles LA
1018 PM CDT Fri Aug 26 2022 ...New UPDATE... .UPDATE... Issued at 1011 PM CDT Fri Aug 26 2022 Quiet evening/night ongoing across SE TX/SW LA. Radar is quiet expect for a few hours south of Cameron Parish, skies are partly cloudy, and temperatures are in the upper 70s to near 80. Only update this evening was to adjust POP grids over the next few hours to account for current trends. The latest HRRR runs show the convection south of Cameron increasing in coverage through the next few hours as it spreads inland, while elsewhere quiet conditions should prevail until sunrise. Thereafter, coverage should increase a bit further through the morning and more substantially through the afternoon hours, similarly to the last several days. 17 && .SHORT TERM... (This evening through Saturday) Issued at 320 PM CDT Fri Aug 26 2022 Mid-afternoon sfc analysis shows an area of low pressure centered over cntl LA with a trailing frontal boundary swwd to the nwrn Gulf and a stationary boundary along the cntl Gulf Coast. Meanwhile high pressure continues to ridge over the nrn Gulf, maintaining a light srly flow ahead of the frontal boundary. Water vapor imagery shows the region remaining under a weakness aloft. Local 88Ds show convection has continued to develop primarily along the boundary, but also along the afternoon sea breeze. Recent CAM again shows today`s diurnal convection dying off around sunset, although with the lingering boundary hanging around and acting as a bit of a focus, along with forecast soundings indicating copious moisture persisting (PWAT values for the foreseeable future generally aoa 2.0 inches), convection could linger a little longer before fully dissipating. Thereafter another round of nocturnal activity is progged to develop over the Gulf and approach the coast prior to sunrise. Given the very wet soils in place across the forecast area, we remain under a marginal risk for excessive rainfall...with the Atchafalaya Basin holding in a slight risk through tonight. The wet weather is progged to continue into Sunday as the boundary meanders around while gradually washing out. A broken record forecast, convection continues to be centered near the coast during the late night hours before spreading inland during the day within a very moist/unstable air mass. For now, the entire forecast area remains in a marginal risk for excessive rain for days 2 and 3. With the elevated rain chances/cloud cover, daytime temperatures are progged to remain below late August norms for the time being. 25 && .LONG TERM... (Saturday night through next Thursday) Issued at 320 PM CDT Fri Aug 26 2022 The upper air pattern will be dominated by a weakening mid to upper level trough over the Central U.S. with high pressure ridging aloft off the SE U.S. and Western U.S. This pattern will slowly transition to a mid to upper ridge building over the Central U.S. and upper level trough deepening over the Eastern U.S. by Friday. This may bring a weak backdoor cool front Thursday afternoon and Friday. Unfortunately, this will not diminish our precipitation chances much during the extended period. With ample Gulf moisture, daytime heating and the seabreeze will be enough to provide scattered to numerous showers and thunderstorms each day, with the best chances during the late morning to early evening hours. With the NBM going way too high on PoPs lately, continued this morning`s trend and went with the 50/50 blend of NBM/BCCONSMOS, which yielded more believable numbers. With the mostly cloudy skies, afternoon highs will continue below normal, averaging in upper 80s to lower 90s. Lows will be in the lower to mid 70s, with near 80 along the coast. By Friday, if the weak front moves through, might be able to knock down the lows in the upper 60s to lower 70s. 08 && .AVIATION... (00Z TAFS) Issued at 706 PM CDT Fri Aug 26 2022 Showers and thunderstorms on a waning trend per radar imagery, will all sites reporting VFR under mostly mid and high level clouds. Expect another round of MVFR and possibly IFR CIGS overnight into SAT morning, with the temporal window based on a blend of latest guidance and persistence. Scattered to possibly numerous showers and thunderstorms are expected again by afternoon, with a PROB30 inserted each terminal for this potential. Winds will remain generally light through the period away from convection/outflows. && .MARINE... Issued at 320 PM CDT Fri Aug 26 2022 Scattered to numerous nocturnal and early morning storms will occur each day. A light onshore flow is anticipated, however winds and seas will be elevated in storms. 25 && .PRELIMINARY POINT TEMPS/POPS... AEX 75 91 75 91 / 30 70 30 60 LCH 74 87 75 87 / 30 70 30 70 LFT 76 88 76 88 / 40 70 20 70 BPT 75 89 76 88 / 30 70 30 70 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$ SHORT TERM...17 LONG TERM....08 AVIATION...13
Area Forecast Discussion
National Weather Service Shreveport LA
955 PM CDT Fri Aug 26 2022 ...New SHORT TERM... .SHORT TERM... (Tonight through Saturday Night) Issued at 934 PM CDT Fri Aug 26 2022 Fair skies with the last of the evening`s anvils fading away. Pops drop off at 10pm so we will update with no changes needed to a fresh evening zones shortly. HRRR has been running dry for the remaining overnight hours during the last few hourly updates. Air temperatures are around 80 degrees this evening with a light easterly wind if any and dew points in the low to mid 70s. The light winds will at times be calm with a good deal of low level moisture (pwat of 1.86 on the evening sounding) that will give rise to more morning low clouds and some patchy fog in much of the four state area, especially those locales with a late day shower like Ruston and Monroe. Overnight lows are on track to the lower and a few mid 70s. Pops return after 7am along I-49 to start the weekend. /24/ && .LONG TERM... (Sunday through next Thursday) Issued at 249 PM CDT Fri Aug 26 2022 Largely unsettled weather continues to be the theme through the long term period as an upper trough drops southward from the Plains while a secondary disturbance drifts northward over the NW Gulf of Mexico. This will allow for at least scattered convection on Sunday with the aid of daytime heating and coverage decreasing overnight. Near to slightly below normal temperatures are expected with highs in the upper 80s to lower 90s. These trends will continue into Monday with slightly milder temperatures due to increased convective coverage as Gulf moisture continues to deeper across the region. By Tuesday into Wednesday, a cold front will drop southward from the Plains into our region. This will maintain good rain chances through mid week as temperatures continue to run below normal with increased cloud cover and convection in the wake of fropa. By late week, upper ridge out west will attempt to build back eastward and become more influential with the frontal boundary pushing farther south toward the coast. In the meantime, medium-range progs also continue to suggest some potential tropical activity potentially affecting the Gulf region heading into the Labor Day weekend so this will bear watching over the next several days given the average peak time of tropical activity in late August and early September. /19/ && .AVIATION... (00Z TAFS) Issued at 703 PM CDT Fri Aug 26 2022 For the ArkLaTex terminals VFR for the night with pm convection dying off in E TX, but still holding on to more than just diurnal along I-20 in LA. KMLU took a pop-up on the chin with brief IFR and a more substantial sea breeze influence. These will linger for an hr or two more with KSHV still in range. Otherwise daybreak will vary from site to site with some MVFR/IFR briefly. Likewise, again the afternoon convection may affect I-20 sites from KGGG to KMLU. SE 5KT will prevail, but variable and gusty near downpours. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 74 90 74 91 / 20 50 10 40 MLU 73 88 73 89 / 20 50 10 50 DEQ 71 91 72 91 / 0 20 10 40 TXK 73 89 74 90 / 10 30 10 40 ELD 70 88 72 88 / 10 30 10 40 TYR 75 90 75 93 / 10 30 10 20 GGG 73 89 74 91 / 10 40 10 30 LFK 74 92 73 92 / 20 50 10 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...24 LONG TERM....19 AVIATION...24