Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/13/23


Area Forecast Discussion
National Weather Service Fort Worth TX
659 PM CDT Mon Jun 12 2023 ...New Aviation, Short Term... .SHORT TERM... /NEW/ Update: The outflow boundary associated with this morning`s convection along the Red River has pushed well south into Central Texas and has limited any convective attempts this afternoon across the Big Country. A few cells have developed and quickly become severe with a threat for large hail west of Mills County and should continue to track east this evening. Elevated showers and thunderstorms are expected to develop along and north of the Red River after midnight. Although widespread severe weather is not expected, steep lapse rates may result in marginally severe hail. Otherwise, a threat for locally heavy rain and strong winds will exist as this activity moves southeast into tomorrow morning. While additional thunderstorms are expected east of I-35 tomorrow afternoon, this will be dependent on the early morning activity. Garcia Previous Discussion: /Today and Tomorrow/ A cold front moved into North Texas last night and stalled just south of the I-20 corridor. Elevated storms developed near the Red River in the early morning hours that has sent a strong outflow and reinforcing shot of mesoscale-driven cold air south. This has resulted in falling temperatures and much more stable air moving into locations north of I-20 over the past couple hours. This will have an impact on the convective forecast later this afternoon. First, depending on how far south the cold air is able to get will push the thunderstorm initiation location south. Second, it will reduce the storm potential for those north of the boundary. A weak shortwave trough is currently moving across West Texas and promoting modest height falls overtop of the forecast area. A surface low is deepening over the Big Country/Concho Valley with a triple point evident on GOES-E Mesosector satellite imagery near Eastland County. This feature may drift a little south due to the strength of the cold pool...as far south as about Comanche. As far as how stable the cold pool will remain will be dependent on how much heating occurs. Stratus behind the cold pool is clearing quickly over North Texas which will help rebound the instability over the next several hours. The airmass over D/FW according to recent ACARS soundings shows a stable airmass from the surface up to about 3 km, or 700 mb. Our tentative plan is to send up a RAOB sounding around 330PM to assess the amount of low- level destabilization. With that being said...the air above 3 km is still unstable with mid-level lapse rates of 8.6 deg C/km. If storms are able to develop and reach this level (either from the surface or elevated), there is potential for rotating updrafts and large hail this afternoon, even behind the cold pool. There have been a few convective attempts in the cool airmass, but they have had little success maintaining much longer than a few minutes. Surface-based convective initiation should occur near the triple point later this afternoon, around 5-7 PM. The initial storms that develop will likely become supercells in short order and move E & SE through the evening. Relatively straight hodographs will support another day of splitting storms, which will send some storms NE overtop of the more stable low-level air. It`s a question of how far north into the cooler air the storms will be able to continue, so the stronger cool air that moved through this morning has improved the outlook for those north of I-20. While the Metroplex and other areas north of I-20 are still at risk of receiving severe weather this evening, the threat is lower and storm coverage should be more isolated than we thought. As far as south of the boundary over Central Texas...the severe threat continues. Large hail, possibly up to baseball size and damaging wind gusts will be the primary threats. There is a low threat of tornadoes, higher than the past couple days, but still low since any tornado would be dependent on meso and stormscale boundary interaction. Storms should start to weaken over Central Texas late tonight, but another night of elevated showers and storms is expected north of the stalled front. The front is expected to linger over North Texas overnight, so we have increased PoPs north of I-20 for the overnight hours. While an isolated severe storm is possible with the late night/early morning activity, most of the storms should remain sub-severe. There will be an increasing threat of flooding overnight, particularly along the Red River. Training storms will be possible with some locations receiving upwards of 2-4" of rain. Tuesday morning convection will move east and decrease in coverage late in the morning before another round of isolated to scattered thunderstorms develop in the afternoon near the stalled front. The best storm and severe chances will be generally along and east of I-35, but a lot will depend on the early morning convection. If the cold pool races south it could dampen storm chances for the rest of the day...giving the all clear for most of the region in regard to severe weather. Bonnette && .LONG TERM... /Issued 243 PM CDT Mon Jun 12 2023/ /Tuesday Night Onward/ A mid level ridge centered over Mexico will flatten Tuesday night as a shortwave traverses the Plains, producing a brief period of zonal flow over North and Central Texas. The shortwave will give our meandering front a subtle push southward Tuesday night, but the front should become stationary again somewhere near or south of the I-20 corridor again on Wednesday. Scattered showers and occasional storms may be ongoing across East Texas Tuesday evening associated with lift ahead of the shortwave. Additional storms may develop in the vicinity of the surface front overnight into Wednesday morning as a modest low level jet develops, but activity should remain fairly isolated. Convection will exit to the east during the day Wednesday as the shortwave heads for the Mississippi Valley. Zonal flow aloft will transition back to anticyclonic Wednesday night into Thursday as the ridge over Mexico extends north into the Southern Plains. Subsidence associated with the ridge will keep a lid on convection for the most part, but the presence of the weak surface front may still lead to isolated thunderstorms Thursday afternoon and evening. Low POPs will hence be needed across Central and East Texas for Thursday. The main message will otherwise shift to intense heat as the ridge overhead continues to strengthen. The 590 decameter height at 500mb should reach the Red River by Friday evening and remain there through the weekend. Triple digit high temperatures will become pretty common over the weekend as a result, with 105+ degree heat indices also a good possibility. Heat related headlines may become needed, and folks with outdoor weekend plans are urged to keep hydrated and take frequent breaks in the shade or an air conditioned building. Also, keep your pets protected and avoid walking them on hot pavement. A brief break from the heat may occur Sunday evening along the Red River, where a disturbance rounding the ridge may generate a brief round of thunderstorms. Otherwise, hot and rain-free weather will remain the norm, at least into the first half of next week. 30 && .AVIATION... /NEW/ /00Z TAFs/ Convection this afternoon and evening remains well away from the terminals, mainly impacting the northern and western cornerposts. While additional thunderstorms may develop this evening near the terminals, the higher potential will exist at ACT. Another round of elevated convection is expected after 07-08Z across the Metroplex terminals, moving southeast through early Tuesday morning. The overnight activity will impact where thunderstorms develop tomorrow afternoon, and subsequent TAFs will address this potential. Garcia && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 72 87 71 92 73 / 60 40 20 5 10 Waco 72 95 73 97 74 / 40 20 20 5 5 Paris 67 79 68 87 68 / 70 60 50 20 20 Denton 68 86 67 91 68 / 60 40 20 5 5 McKinney 69 84 68 89 70 / 70 60 30 10 10 Dallas 72 88 71 93 72 / 60 40 30 10 10 Terrell 71 87 70 90 71 / 60 40 40 10 10 Corsicana 74 91 74 93 75 / 30 20 30 5 10 Temple 72 96 73 99 74 / 40 20 10 5 5 Mineral Wells 69 89 68 92 70 / 40 20 10 5 5 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$