Area Forecast Discussion
Issued by NWS Dallas/Fort Worth, TX
Issued by NWS Dallas/Fort Worth, TX
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190 FXUS64 KFWD 241814 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 114 PM CDT Fri May 24 2024 ...New Short Term, Aviation... .SHORT TERM... /NEW/ /Today and Tomorrow/ Scattered thunderstorms are expected to develop this afternoon and evening. Some storms will be severe. Large hail greater than 2 inches, damaging wind gusts of 60-70 mph, and a low tornado threat will exist. Mesoscale Setup... We`re watching several boundaries as we move into the early afternoon. The first, and most notable, is a cold front moving south through Oklahoma. It is currently moving through OKC/Lawton and will continue moving south through the day. Ahead of this, a weak pre-frontal trough (likely originating from overnight convection well to our north) extends from Wichita Falls to Abilene. A dryline is observed over the Big Country near Abilene and San Angelo that will advance east through the afternoon. Additionally, a remnant outflow boundary is currently moving across the Red River in Montague County and extends northeast toward Arkansas. Overtop of all of this (pun intended), a shortwave trough is evident on water vapor satellite imagery that will provide broad mid-level ascent over our area through the afternoon and evening. Timing and general convective trends... As of this writing, the atmosphere over the Metroplex is still heavily capped. A combination of forced ascent from the boundaries and surface heating should gradually erode the cap over the next few hours. The first storms of the day should develop between ~3-4 PM where the cold front intersects the pre-frontal trough. This is expected to take place northwest of the Metroplex somewhere between Bowie and Sherman. A few isolated, and elevated, storms are possible over western Central Texas between 1-4 PM where the mid-level shortwave trough interacts with the dryline. We`ve noted a couple convective attempts in this area already today, but the lack of strong low-level ascent and plentiful dry air aloft is precluding thunderstorm development for now. Today`s initial storms should be isolated, but expect the coverage to gradually increase as we approach sunset, with the most widespread convective activity taking place between ~7-9 PM. The storms should also move east/southeast, slowly moving into Central Texas overnight. Most of the storms will end in the early morning hours, between about 1-2 AM. Severe threat and convective mode... The initial storms that develop will likely become supercells in rather short order. The modified morning sounding indicates MLCAPE values near 3500 J/kg, with some model soundings indicating CAPE values exceeding 4-5000 for some areas later this afternoon. The large CAPE values are aided by a very warm and moist surface, with 70-75 degree dewpoints extending all the way across the Red River. Additionally, observed mid-level lapse rates approaching 9 degC/km are resulting in very "fat" CAPE profiles, particularly within the hail growth zone. While deep-layer shear isn`t off the charts, there should be sufficient shear to support both left and right splitting storms throughout the afternoon and evening. The very high buoyancy supports the potential for large, some very large (2-3 inches), hail. While the damaging wind threat isn`t the highest threat today...dry air in the mid-levels and precip-loaded storms will allow for damaging wind gusts from any of today`s storms, particularly this evening and overnight when cold pools merge and the convective mode becomes more messy. The low level winds do not indicate a widespread threat or high risk of tornadoes, however, low LCLs and mesoscale interactions will locally enhance low-level shear and the tornado potential with the most intense supercells. Opposite of the wind threat, the threat of tornadoes will be highest in the late afternoon and early evening. We have advertised the potential of severe weather again tomorrow, however we are less confident of storms in our area tomorrow. It now appears that they dryline will be well to our west, with most of the convective activity remaining in western/central Oklahoma. We won`t go into much detail regarding tomorrow, and will provide more details in future forecast updates. Heat and Humidity... It will be very hot and humid today and tomorrow, regardless of thunderstorm development. We are forecasting high temperatures in the low to mid 90s with heat index values in the low 100s both days. Parts of Central Texas will likely meet our Heat Advisory criteria (heat index > 105 for 2 days), but we are not confident enough of which counties will eclipse that mark today. Due to this, we are not planning on issuing a Heat Advisory at this time. Bonnette && .LONG TERM... /Issued 417 AM CDT Fri May 24 2024/ Update: /Rest Of The Holiday Weekend Through Next Week/ Overall weather trends and timing with synoptic features, lift, and storm potential below still look on track. Saturday is the one day of uncertainty as the strength of the cap will play a big role if any storms develop at all thanks to a brief shortwave ridge developing overhead. For now, have maintained low strong to severe storm chances across the West and toward the immediate Red River Valley, where very warm temperatures and lifting mechanisms will be juxtaposed with the weakest cap strength. We`ll continue to fine tune this part of the forecast through tonight, as above normal temperatures occur across most of the area. 05/Marty Previous Discussion: /Friday through Thursday/ The weather pattern will remain active as we head into the weekend with low level moisture staying in place and multiple shortwaves moving though southwest flow aloft. Scattered thunderstorms will be possible on Friday along and ahead of a cold front and dryline. The best storm chances will be during the late afternoon and early evening, mainly east of the I-35 corridor. A cap of warm air will limit/prevent storms from developing, but if the cap breaks, storm could become strong to severe quickly, capable of producing large hail and damaging winds. The loss of surface heating and the passage of the shortwave will end storm chances Friday evening. Saturday morning should start out rain-free but another shortwave will emerge out of West Texas in the afternoon while a dryline approaches from the west. The best storm chances will be from the Red River northward where the cap is most likely to break, but there is at least a low potential for storms across most of North Texas. Any storm that manages to develop will have potential to become severe. Storms will shift eastward with the passing shortwave Saturday night. Sunday should be rain-free with no discernible source of lift on either the synoptic or mesoscale. The passage of a shortwave across the Northern and Central Plains Sunday night will send a cold front southward through the region on Memorial Day. We don`t anticipate any storms with the front since moisture will be very limited above 850 mb. However, there may be just enough moisture across Central Texas for a few thunderstorms Monday evening. The front will bring a temporary end to the oppressive humidity, with dew points falling into the upper 50s to lower 60s by Tuesday morning. The front will lift slowly back to the north Tuesday night through Wednesday, resulting in low level moisture return and a return of thunderstorm chances. Storm chances will increase Wednesday night through Thursday with the passage of a shortwave. High temperatures Friday through Sunday will be generally in the 90s and low temperatures will be in the upper 60s and 70s. High temperatures Memorial Day through Thursday will be slightly cooler with mainly 80s and lower 90s. Lows will finally fall below the 70s for most locations the first half of next week. 79 && .AVIATION... /NEW/ /18Z TAFs/ MVFR ceilings have stuck around longer than expected, but still expect the stratus to lift/scatter over the next 1-2 hours. The main impact to aviation today will be thunderstorms that develop over the next several hours. A few isolated storms will be possible SW of D10 that may create deviation in the Glen Rose cornerpost through about 20Z. More storms are expected to develop after 20-21Z, northwest of D10 that become more widespread as we continue into the evening. It is now more likely than not that direct D10 impacts take place, mainly between 22-02Z this evening. There is potential for large hail and erratic wind gusts of 50 kts with this activity. Storms should then move south and east after 02-03Z, with all storms ending around 06Z tonight. In general...the northern cornerposts will likely be impacted first, then D10 itself, then the southern cornerposts overnight. Another round of MVFR stratus is expected tonight while gusty south flow prevails for much of the TAF period. Bonnette && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 94 72 93 76 97 / 40 40 0 5 0 Waco 91 72 93 75 95 / 20 40 0 5 0 Paris 89 69 89 73 91 / 50 40 5 10 0 Denton 93 70 93 75 96 / 40 20 5 10 0 McKinney 91 70 91 75 94 / 40 30 0 10 0 Dallas 94 73 93 76 96 / 40 40 0 5 0 Terrell 90 71 92 75 93 / 30 40 0 5 0 Corsicana 91 71 93 77 94 / 10 40 0 0 0 Temple 91 72 93 75 95 / 20 40 0 5 0 Mineral Wells 94 69 95 75 97 / 20 20 10 10 0 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$