####018008911#### FXUS64 KFWD 260037 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 737 PM CDT Thu Apr 25 2024 ...New Short Term, Aviation... .SHORT TERM... /NEW/ /Through Friday Evening/ Relatively cloudy and seasonable warm conditions prevail across North and Central Texas this evening with current temperatures in the 70s and southerly winds still gusting to 15 to 25 mph. Aloft, synoptic-scale ascent is beginning to increase as a shortwave trough ejects into the Central Plains. At the surface, the associated low near the Colorado and Kansas border is deepening, while the dryline extending southward through the Texas Panhandle sharpens. Given the limitations to solar insolation today, a stout capping inversion remains at around 700-800mb on the evening sounding from Ft Worth, which should continue to inhibit convection until stronger forcing for ascent arrives. Later tonight, thunderstorm initiation is expected near the Caprock Escarpment as the dryline begins to move eastward. Any initially discrete activity that develops along the surface boundary should quickly organize into eastward/northeastward moving clusters or linear segments due to the largely unidirectional wind profile. East of the dryline, a 30-40 kt LLJ will continue to transport Gulf moisture towards the Red River this evening. With surface dewpoints climbing into the lower 70s beneath mid level lapse rates of 8-9 C/km, the air mass will remain moderately to strongly buoyant (MUCAPE > 2000 J/kg) through the overnight hours. Large hail and damaging winds are the main threats as this activity moves into our western zones. However, there is also the potential for an isolated tornado or two given the quasi-linear convective mode. A weakening trend is expected as convection pushes east of the I-35 corridor and encounters increasing convective inhibition. According to the latest ensemble and deterministic guidance, the timeline for the line of storms is as follows: - Reaching the Big Country/Western North Texas - by 3-5 AM - Reaching the I-35 Corridor - by 6-9 AM - Exiting The Region - by 11 AM-1 PM By the afternoon, the dryline is progged to stall west of the I-35 corridor as the parent upper trough lifts into the Northern Plains and Upper Midwest. Despite the stalled surface boundary and diminishing large-scale ascent, we cannot rule out additional development of scattered showers and storms as the environment remains unstable. Any thunderstorms that develop will have the potential to become severe with a threat for large hail and damaging wind gusts. By Friday evening, ongoing activity should begin to taper off as North and Central Texas will be under the influence of weak shortwave ridging. Highs on Friday will range from the mid 70s in East Texas to the mid 80s in western North Texas. 12 && .LONG TERM... /Issued 313 PM CDT Thu Apr 25 2024/ /Saturday Through Early Next Week/ There will be two potential rounds of severe weather over the weekend. The first of which will be more isolated through Saturday afternoon, with a second and more widespread round late Saturday night into early Sunday morning. The atmosphere will be primed for all modes of severe weather through both rounds, with large hail and damaging winds being the main concerns. There is a low chance for a few tornadoes, mainly for the second round of thunderstorms through Sunday morning. On top of that, there is a low chance for isolated instances of flash flooding, mainly along the Red River. Increasing surface moisture ahead of a dry line and an approaching Pacific cold front will interact with what could be a largely untapped warm sector draped across North and Central Texas. The overall extent and coverage of convective activity through Saturday afternoon and evening will depend on the initial placement of the dry line that will be positioned off to our west. This convection will likely remain quite isolated, only impacting our westernmost counties before weakening as they encounter a less favorable storm environment thanks to a capping inversion. Of course, the strength of the cap will be the big question when it comes to the extent and coverage of this first round of thunderstorms. Large hail and damaging winds will be the primary threats with these storms, with a low chance for an isolated tornado or two through late Saturday afternoon and evening. The second round of thunderstorms will start as the Pacific cold front finally catches up to the dry line and begins its journey east through our region. Convection will fire off along this boundary as it moves through North and Central Texas, bringing along with it the potential for severe weather. It's likely that convection will start off more discrete before quickly up-scaling into a linear system of storms. All modes of severe weather will be possible as this moves through late Saturday night into early Sunday morning. Storm mode will partially dictate the probability of each hazard as the storms evolve over time, and will certainly be worth monitoring as higher resolution guidance continues to come in. The overall timing for this will depend on how quickly these storms push through. Given the overall setup, it's possible this line of storms will take all of Sunday to push through our entire forecast area. This will increase our flash flooding potential across portions of East Texas and will be worth watching. On top of these storm chances, the weekend will be quite breezy as ambient winds approach 20 to 30 mph. Gusts upwards of 40 to 45 mph will also be possible on Saturday, which will potentially exacerbate our severe weather potential. A Wind Advisory will likely be necessary for our entire forecast area on Saturday. An unsettled weather pattern will likely continue through the start of next week, with a temporary break from storm chances before our next system begins working it's way into our region toward the end of next week. Continue to check back for updates to the forecast regarding our severe weather potential over the weekend and regarding our next storm chances later next week. Reeves && .AVIATION... /NEW/ /00Z TAFs/ Ceilings continue to fluctuate between MVFR and VFR, however, MVFR conditions will become widespread by 04z with no improvements anticipated until tomorrow afternoon. Gusty south winds will prevail through the overnight hours with sustained speeds of 15-20KTs and gusts to 25-35KTs expected. These wind speeds are not associated with any convective activity. Thunderstorms will develop northwest of the D10 airspace around 04-06Z growing steadily into clusters or line segments as they approach the TAF sites. Have maintained VCTS at all Metroplex terminals at 11Z with a TEMPO group for TSRA from 12-14Z. These storms may be severe with mainly a large hail and damaging wind gust threat. A weakening trend is expected as this activity approaches the TAF sites, though these storms could still be strong to marginally severe and capable of producing hail and strong winds as they reach the Metroplex. Have introduced more pessimistic visibility restrictions along with the potential for higher gusts in the vicinity of any convective clusters/lines. Storms should exit the region by mid- day but there is the potential for additional thunderstorm development during the afternoon, especially near and east of the I-35 corridor including the DFW area. Confidence in this development is low however, so we will refrain from introducing any mention of TS with this issuance. There should be enough instability available to support large hail and damaging wind gusts with any storms that do develop. There are additional storms chances just beyond the end of the extended TAF period. 12 && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 69 80 70 83 68 / 50 90 10 50 70 Waco 70 79 70 83 68 / 30 70 10 30 50 Paris 68 76 67 82 68 / 40 90 30 50 60 Denton 67 81 68 81 65 / 60 70 10 60 80 McKinney 68 79 68 82 68 / 40 90 20 50 70 Dallas 69 80 70 83 68 / 40 90 20 50 70 Terrell 69 77 69 83 68 / 30 80 20 40 60 Corsicana 71 80 70 85 70 / 20 70 20 20 40 Temple 70 79 70 83 68 / 20 60 10 20 50 Mineral Wells 67 86 67 81 63 / 80 40 5 60 80 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ ####018005948#### FXAK68 PAFC 260039 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 439 PM AKDT Thu Apr 25 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: This afternoon through Sunday afternoon)... Few changes to the forecast in the near-term. An upper low in the Bering Sea is poised to pivot towards British Columbia through the weekend, weakening the fair weather ridge that had been in place over Mainland Alaska. For today, a shortwave trough moves across the Mat-Su and Copper River Basin as it transits the western flank of the ridge. Lift from this shortwave, in combination with instability due to daytime heating, could lead to scattered showers in Susitna Valley this evening. Precipitation chances further increase from tonight through Friday afternoon as the front currently over Kodiak Island moves north towards Kenai Peninsula. Overall, not much precipitation is expected for the Mainland as the front will be weakening as it approaches. The bulk of this light precipitation will occur along Eastern Kenai Peninsula, with a small chance for stray showers to move inland. More active weather arrives by late Friday morning/early Friday afternoon as a North Pacific low moves towards Kodiak Island and is enhanced by a shortwave trough rotating around the upper low. Its associated front will be wetter than what Kodiak Island has experienced yesterday and today, with forecast rain amounts of around 1-1.5 inches for Eastern Kodiak Island and less than 1 inch for Western Kodiak Island. This front should remain far enough south that the Southcentral Mainland will be mostly dry. Through Saturday, the low near Kodiak Island will descend southwards, bringing a return to drier and warmer conditions across Southcentral Alaska as weak high pressure builds in. Instability due to daytime heating, in addition to shortwave troughs moving across the Mainland, could lead to convective showers in the Copper River Basin for Saturday afternoon/evening and Sunday afternoon/evening. For now, it's been difficult to hone in on the showers because the upper level pattern becomes a bit more disorganized by the weekend, leading to uncertainty regarding where the upper level shortwaves will go. We'll be keeping an eye on these showers and their convective potential as we continue to update the forecast. -KC && .SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)... The weather pattern has been somewhat repetitious the past couple of days with a nearly stationary cutoff low situated west of the Pribilof Islands. Broad cyclonic flow around the low has promoted gusty conditions across the western Bering and through the Alaska Peninsula. A small swath of northwesterly small craft winds remain immediately north and east of the Central Aleutians this evening. These winds will push through the Islands of the Four Mountains and into the Pacific side of Nikolski tonight. Otherwise, a few areas of light showers are persisting over Southwest Alaska. Evening radar shows rain over Tuntutuliak and Bethel as shower activity lifts northward toward the YK Delta. Additional rain is noted from Koliganek and Lake Iliamna up to Sleetmute. The western Bering low is forecast to begin a weakening trend through Friday morning as it shifts southeastward as an open wave, to be eventually absorbed by a developing trough over the western Gulf of Alaska tomorrow afternoon. A gradual decrease in shower activity is forecast across Southwest Alaska through Saturday morning as a result. Temperatures over the Bering and Aleutians will remain at or below normal into the weekend while temperatures over Southwest Alaska will remain at or above normal. && .LONG TERM FORECAST (Days 4 through 7: Mon through Thu)... By Monday morning, a familiar ridge over Southcentral will still be lingering in the area, continuing the clear pattern. An upper level trough will be situated over the southern Alaska Peninsula, crossing into the southwestern Gulf of Alaska, and a new upper level trough entering the western Bering Sea behind it. Through Tuesday, the ridge will likely extend from Southcentral into Southwest Alaska following the departure of the AKPen trough, while the western Bering system pushes a front across the Aleutians, likely reaching Unalaska by late Tuesday. The front is expected to generally weaken as it approaches Southwest and the resident ridge, but the parental low pressure system behind the front will likely move over the Western and Central Aleutians through Wednesday. By Wednesday afternoon, the ridge over southern Alaska may begin to weaken as the upper-level support shows signs of shifting out of the area. This may allow for influence from the Bering low to move into Southwest Alaska and even Southcentral Alaska as the system approaches by late Thursday. Gauging impacts from this low in Southwest and Southcentral is still precarious given the uncertainty regarding the ridge movement, as well as the location/progression of the low itself. However, given the prolonged shift towards warmer weather over the next week expected, impacts from this system will likely not be winter weather. Although the overall synoptic setup is in fair agreement for the extended period, the details could mean bigger differences in the QPF and wind fields across the Bering and Southwest Alaska. -CL $$ .AVIATION... PANC...VFR conditions will persist. Southeast winds 10 to 15 kts are expected to develop over the airport late this afternoon into the evening. Winds are then expected to become light and variable again overnight. -CC && $$