Area Forecast Discussion
Issued by NWS Dallas/Fort Worth, TX
Issued by NWS Dallas/Fort Worth, TX
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137 FXUS64 KFWD 281018 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 518 AM CDT Tue May 28 2024 ...New Short Term, Aviation... .SHORT TERM... /NEW/ /Moving Into Mid Week/ The unsettled weather with periodic showers and storms, some strong to severe and flooding coming back into the picture late tonight and Wednesday. A weak surface boundary continues to be draped along or just north of the I-20 corridor as earlier storms and associated outflows have only solidified this boundary evening. However, this lull in weather will be short-lived, as a 25-35 kt southeasterly LLJ feeds into an elevated boundary up through 850mb up across Northwest Texas and Southern OK through the overnight hours. As the next shortwave round the dampened mid level ridge to our west, another potential complex of storms will develop to our north and west during the predawn hours. Models, though at different magnitudes will bring this into North Texas around sunrise and eventually Central Texas later in the morning or afternoon. More severe weather will be possible as this storm cluster ridges southeast along the instability gradient. Initially, large hail will be the primary hazard with storms potentially being semi-elevated, then as a cold pool evolves we could see damaging winds as well. Just a few hour of removing one severe storm watch, another severe tstorm watch will be forthcoming and will go to around dawn/7 am, as elevated storms are already going up over Southwest OK/Northwest TX. Easterly winds will continue with a slightly cooler morning that previously over the holiday weekend, with some upper 60s to lower 70s being the rule. As the storm complex weakens some this afternoon across Central Texas, numerous surface boundaries and temperature/instability gradients from cloudy to partly cloudy skies will only play new roles to act as focal points for another round of storms, potentially an MCS this coming evening and overnight into Wednesday morning. Models, especially CAMs are struggling as to be expected in these active northwest flow environments and no knowledge said mesoscale surface boundaries. Though surface instability won`t be as extreme as recent days, plenty of shear and lift, along with very steep lapse rates. Severe weather hazards of large hail and damaging winds will once again be impacts again, though we can start adding localized flooding at this point. Despite the increasing flood threat, the uncertainties noted above gives me low confidence on where/when for any Flood Watch issuance. Later today, that should be more clear from this early morning`s storms to hopefully the CAMs getting a better handle with the MCS track tonight. The MCS should be ongoing Wednesday morning as well, just the "where" of the main track and worse weather conditions is uncertain once again. This system should become more of a damaging wind threat around this time, though isolated large hail will remain possible on Wednesday. This system will weaken before midday laying more surface boundaries from outflow with more scattered development late in the day. The only saving grace from the very active severe weather and locally heavy rainfall will be much cooler high temperatures mostly in the 80s with lows Wednesday morning mainly in the 60s. 05/Marty && .LONG TERM... /Issued 312 PM CDT Mon May 27 2024/ Update: The forecast trends discussed below generally remain on track, therefore no significant changes were made to the previous forecast. The first in a series of weak shortwaves/perturbations embedded in the W/NW flow aloft will shift over a High Plains dryline on Tuesday. The resulting thunderstorm complex will carry primarily a damaging wind threat as these storms progress east/southeast into our area during the late afternoon and evening hours on Tuesday. There will also be a threat for isolated instances of large hail, particularly south I-20 and west of I-35. This repetitive pattern of passing disturbances and daily storm chances will continue through the end of the week. Multiple rounds of heavy rainfall will likely lead to an increasing flood threat, especially given vulnerable soils due to recent rainfall. This unsettled pattern is likely to continue through the upcoming weekend as the weakening upper ridge shifts to the east late week. In its wake, a series of shortwave troughs riding around the upper low over the Gulf of Alaska will eject across the northern Rockies keeping our pattern somewhat amplified. 12 Previous Discussion: /Tuesday Evening and Beyond/ An active northwest flow pattern will set up over North and Central Texas by midweek as the region becomes sandwiched between a developing ridge over portions of the Desert Southwest/northern Mexico and troughing over the Great Lakes region. An initial shortwave perturbation looks to shift over a sharpening dryline late Tuesday afternoon/evening, initiating isolated to scattered convection over portions of West Texas and the Big Country. This activity will likely develop initially as supercells before growing upscale into a cluster of cells or possibly an MCS. With a northwesterly mean cloud-layer wind and a 25-35 southeasterly LLJ, this complex of thunderstorms will rapidly shift southeast toward our forecast area late Tuesday evening into the overnight. Where the initial convection occurs will play a large part in determining where this complex tracks Tuesday evening/night. However, there are several signals that our western Central Texas counties could witness the brunt of this complex`s impact. These convective systems tend to track along instability gradients, and most guidance right now places that SBCAPE gradient/weak, stalled frontal boundary generally along/south of the I-20 corridor Tuesday night. This track over western Central Texas and the Hill Country may also be reinforced by outflow from thunderstorms near the Red River Valley earlier in the day. Damaging wind gusts along the leading edge of this complex and isolated hail will be the primary hazards. Latest high-resolution guidance currently places an area along/southwest of a Breckenridge- Hillsboro line in the track of this potentially severe line of storms. The portion of this complex north of the instability gradient will likely be sub-severe with a lack of surface-based instability present. PWATs approaching 1.9-2.1" and warm cloud depths greater than 15,000ft will make these thunderstorms very efficient rainfall producers and several locations beneath these storms could pick up a quick 2-3" of rain. Continue to monitor the forecast over the next couple of days as we further refine location and timing details. This active pattern will continue through the rest of the work week with daily chances for thunderstorms over portions of North and Central Texas through at least Saturday. Coverage Wednesday may be more isolated, but the next chance for more widespread rainfall looks to arrive late Thursday into Friday as another compact shortwave progresses overhead through the northwesterly flow aloft and the aforementioned stalled frontal boundary lifts north toward the Red River enveloping most of the region in moderate surface-based instability. Severe weather will be possible at times. Additionally, multiple rounds of heavy rainfall will increase the flooding threat, especially over already saturated areas. Otherwise, temperatures will be slightly tempered by clouds and precipitation with widespread afternoon highs in the 80s and low 90s and overnight lows in the mid-60s to low 70s. Langfeld && .AVIATION... /NEW/ /06z TAFs/ Earlier storms have cooled the BL enough for some high MVFR for a few hours before environment S flow at 925mb breaks out to VFR before the next round of storms arrives from the north from OK around 10z-12z. I`ll will carry MVFR cigs with VCTS from 12z-15z with a TEMPO group for MVFR cigs with IFR vsbys in TSRA. Otherwise, kept similar trends beyond this time with prevailing ESE winds around 10 kts and VFR returning by 18z, as we experience a brief reprieve before tonight`s MCS. Speaking of, I removed the TEMPO group beyond 00z Wed due to very low confidence on timing and track of a nocturnal MCS expected Tues night on latest CAMs and will just hold a VCTS/CB group from 02z onward. 05/Marty && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 74 86 69 83 70 / 40 70 60 50 30 Waco 75 90 70 82 69 / 20 30 70 60 30 Paris 67 81 67 81 64 / 30 60 50 60 30 Denton 69 84 67 82 67 / 40 70 60 50 30 McKinney 71 83 68 82 67 / 40 70 60 50 30 Dallas 74 87 69 83 69 / 40 70 60 50 30 Terrell 71 85 68 82 67 / 30 70 50 50 30 Corsicana 74 87 69 84 69 / 20 40 50 60 30 Temple 75 90 70 83 69 / 20 30 70 50 30 Mineral Wells 73 86 68 81 69 / 40 50 70 50 30 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$