Area Forecast Discussion
Issued by NWS Shreveport, LA
Issued by NWS Shreveport, LA
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647 FXUS64 KSHV 091744 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 1244 PM CDT Thu May 9 2024 ...New AVIATION... .UPDATE... Issued at 1056 AM CDT Thu May 9 2024 As of 10:30 AM this morning, temperatures are approaching the lower 80s once again under mostly sunny skies. The atmosphere remains conducive for severe weather later today as indicated in some parameters from the 12Z morning sounding (mid-level lapse rates above 7 C/km, CAPE above 2000 J/kg, DCAPE above 1000 J/kg), therefore a special sounding will be forthcoming in the next few hours to requantify these parameters. Otherwise, temperature maximums will reach or exceed 90 degrees along and south of the I-20 corridor. With weather and observed trends continuing as anticipated, forecast grid adjustments were not necessary at this time. /16/ && .SHORT TERM... (Thursday through Friday) Issued at 314 AM CDT Thu May 9 2024 Vast array of remnant outflows are present on the KSHV radar this morning following the collapse of late Wednesday afternoon and evening convection. These have supported some brief thunderstorms across NW Louisiana that have since collapsed. As of 2 AM CDT, the KSHV ASOS reported a temperature reading of 80 deg F over a 73 deg F dew point. At the same time, sfc obs across the region still advertise persistant southerlies, indicating that much of the Ark-La-Tex remains on the south side of the advancing cold front to the north, and just east of an intersecting dry line across South-Central Texas. How far south this cold front advances, prior to stalling briefly late this morning, will set the stage for where the best instability will be located this afternoon, along with where the dominate convective evolution traverses by the evening. This afternoon through early Friday AM: By this afternoon, general thinking is for the sfc boundary to be located somewhere between the I-20 and I-30 corridor. To the west, closer to the DFW metroplex, the influence of the dryline and cold front intersection, along with additional forcing from a shortwave trough across Texas, will allow for supercell thunderstorms to initiate within another volatile environment ahead of the cold front. As storms grow and multiply in coverage to the west of the local FA, morning CAMs suggest gradual clustering, ultimately supporting the development of a multi-cell complex that will enter another impressive environment across the Ark-La-Tex. Once again, sfc theta-e recovery will compliment SBCAPE profiles exceeding 4000 J/kg along and south of the I-20 corridor, while co-located in an area of 700-500 lapse rates above 8.0 C/km, with moderate bulk shear values present. High temperatures in the upper 80`s and low 90`s this afternoon will only aid to the aforementioned instability. Given the parameters available, general thinking is for an evolving MCS to trek into the local FA, presenting the threat for damaging straight line winds, hail and a few brief embedded tornadoes. Still some uncertainty surrounding the overall evolution and strength of the possible MCS as it works across the CWA, with more questions surrounding the swath of possible wind impacts. As a result, the latest day 1 Storm Prediction Center Outlook has expanded the Enhanced Risk (level 3 of 5) to cover much of the local FA. Friday AM through the end of Short Term Period: As the progged convective complex works east of the local area by early Friday morning, southward advancement of the sfc boundary will follow. The boundary should be located south of Toledo Bend around sunrise, with high pressure quickly advancing into the region. This will support drier conditions to end the week, with an introduction to near-normal temperatures as we head into the weekend. RK && .LONG TERM... (Friday Night through Thursday) Issued at 314 AM CDT Thu May 9 2024 While starting dry, the pattern once again turns towards the return to rain chances to finish the weekend and heading into early next week. Upper ridging overhead will shift eastward by Sunday afternoon as large scale forcing supports the return of moderate precip and embedded thunderstorms by the late afternoon and evening. The pattern will continue into Monday as an upper-low parks across north Texas and southern Oklahoma, prevailing synoptic forcing locally to redevelop additional showers and thunderstorms. Some members of the large scale guidance do suggest that rain chances carry over into parts of Tuesday, so have elected to carry those chances. A second story to the long term package will be the gradual climb of maxT`s locally, starting in the low 80`s and finishing close to 90 deg F by mid week. RK && .AVIATION... (18Z TAFS) Issued at 1231 PM CDT Thu May 9 2024 For the 09/18Z TAFs, IFR to MVFR CIGs prevail across area terminals and will struggle to recover significantly through the remainder of the afternoon. Conditions will deteriorate from west to east by the late afternoon and early evening hours as a complex of strong thunderstorms moves out of east Texas and into Louisiana and Arkansas, parallel to the Interstate 20 corridor. Destructive winds as high as 75 mph will be possible with these storms, as well as damaging large hail and possibly a tornado or two. This will be a fast-moving complex and should depart the area quickly during the overnight and pre-dawn hours, with a return to VFR conditions to follow. Winds will be variable through the afternoon and evening before becoming northeasterly and northerly behind this evening`s storms, continuing through the end of this forecast period at sustained speeds of 5 to 10 kts. /26/ && .PRELIMINARY POINT TEMPS/POPS... SHV 68 84 62 82 / 60 0 0 0 MLU 66 83 59 81 / 50 0 0 0 DEQ 59 80 54 81 / 30 0 0 0 TXK 63 82 58 82 / 40 0 0 0 ELD 61 81 55 81 / 30 0 0 0 TYR 65 82 60 80 / 60 0 0 0 GGG 64 83 60 81 / 60 0 0 0 LFK 67 85 62 81 / 50 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...16 LONG TERM....16 AVIATION...26