Area Forecast Discussion
Issued by NWS Dallas/Fort Worth, TX
Issued by NWS Dallas/Fort Worth, TX
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754 FXUS64 KFWD 281005 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 505 AM CDT Tue May 28 2024 ...New Short Term, Aviation... .SHORT TERM... /NEW/ Update: MCS in full surge mode now along and north of the Hwy 380 corridor and should continue surging into the DFW Metro and I-20 corridor through daybreak. Two severe tstorm watches are in effect, 339 for areas along/N of Hwy 380, then further S/SE through the rest of the DFW Metroplex into Central Texas through 11 am. WIth little confidence of temperatures after this first round of morning convection moves through, have left every other forecast parameters the same...including temperatures and winds. Forecast updates will continue throughout the day, as a very challenging forecast lies ahead the next 48-72 hours, as several rounds of showers/storms, some severe and some with heavy rainfall that may result in isolated instances of flash flooding Wed through Fri. 05/Marty Previous Discussion: /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. 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 rounds 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 hours 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 than 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 311 AM CDT Tue May 28 2024/ /Wednesday Night Onward/ North and Central Texas will remain beneath the northeast flank of a mid level ridge through this weekend, keeping an active northwest flow pattern in place through the foreseeable future. Wednesday`s convection will wind down in the late evening, but additional storms may develop in the overnight hours into Thursday morning as a ripple in the upstream flow aloft approaches. These storms would likely be elevated above a capping inversion, and would likely dissipate mid to late morning as boundary layer mixing disrupts the low level jet. Some storms may be capable of producing marginally severe hail before falling apart. The ever-present stationary front and any lingering mesoscale boundaries from morning convection will serve focus for additional development Thursday late afternoon and evening as a stronger shortwave approaches. Flow aloft will not be particularly strong compared to recent days, but strong enough to produce around 40 kt of effective shear. This will sufficiently support severe thunderstorms when coupled with the 4000+ j/kg of ML CAPE, with large hail the primary threat through the evening. Potential upscale growth would shift the main threat to damaging wind gusts during the overnight period before activity exits to the southeast Friday morning. The tornado threat appears low at this time due to unimpressive low level helicity values, but low LCLs and the presence of surface boundaries may allow for a tornado or two. Heavy rain and flooding from training thunderstorms will also be a possibility. A lull in thunderstorm activity looks possible on Friday in the wake of the Thursday night system, though isolated redevelopment cannot be ruled out if the atmosphere recovers Friday afternoon. The dryline will become active again on Saturday as the next shortwave trough approaches from the west. Convection will likely initialize across the Big Country in the late afternoon, then spread east across the western half of the forecast area Saturday evening. It is a tad early to speculate on severe potential, but time of year and the upper level pattern appear conducive for at least a low-end severe weather concern. Another lull on Sunday will be followed by additional storm chances late Monday as the ridge retrogrades slightly and a northwest flow MCS appears possible. Multiple rounds of rain and storm chances should keep temperatures mostly in check for the Thursday through Monday period. The ridge will expand northeast around the midweek period of next week, increasing heights across the region. Strengthening subsidence may shut off precipitation chances and return the summer heat to the region towards the end of the forecast period. 30 && .AVIATION... /NEW/ Update: /12z TAFs/ Outside of speeding up TSRA, some with GR/GS and very gusty outflow winds by 1-2 hrs, will leave the rest of the TAF forecast static with too many uncertainties for any kind of confidence or wholesale changes. 05/ Previous Discussion: /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 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 86 69 83 71 85 / 70 60 50 30 30 Waco 90 70 82 71 85 / 40 80 60 20 30 Paris 81 67 81 67 80 / 70 80 70 30 40 Denton 84 67 82 69 83 / 70 60 50 30 30 McKinney 83 68 82 69 82 / 80 70 60 30 30 Dallas 87 69 83 72 85 / 70 60 50 30 30 Terrell 85 68 82 69 84 / 70 60 60 30 30 Corsicana 87 69 84 71 86 / 50 60 60 20 30 Temple 90 70 83 71 86 / 30 70 50 20 20 Mineral Wells 86 68 81 69 84 / 50 70 50 20 30 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$