Area Forecast Discussion
Issued by NWS Shreveport, LA
Issued by NWS Shreveport, LA
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104 FXUS64 KSHV 311758 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 1258 PM CDT Fri May 31 2024 ...New AVIATION... .UPDATE... Issued at 955 AM CDT Fri May 31 2024 Tricky update today that will bleed over into the overnight hours as we should continue to lose storm coverage and intensity with the precipitation currently across our southern zones with an uptick in convection expected later today near the I-30 Corridor of NE TX, SE OK and SW AR with the greatest storm coverage expected this afternoon across the eastern half of our region including Northern Louisiana. This seems plausible but is greatly tied to just how much differential heating we see today. The forcing is there as the upper level trough axis is basically directly ovhd at this time and will be moving slowly eastward during peak heating, thus it would make sense for the greatest storm coverage to be across our eastern half late this afternoon into the evening hours before dissipating late tonight. For this reason, have redrawn pops to coincide with the above thinking and continued this trend into the evening and overnight hours as well. For the Flood Watch, will hold onto all of it, even though I am most concerned with the eastern half of our region as outlined above. We will likely be able trim at least the western half of it out with the afternoon package but will keep all options open once we have new model guidance to look for the afternoon package. Update has been sent...13. && .SHORT TERM... (Friday through Saturday) Issued at 236 AM CDT Fri May 31 2024 This pesky NW flow pattern continues to deal blow after blow with the next round of convection already advancing into our western zones early this morning. Fortunately, the incoming convection is lacking in severity so far compared to what we observed yesterday. In fact, the last remnants of the previous round are still exiting our far eastern zones after producing numerous wind damage reports and several inches of rainfall in some cases. With that in mind, have opted to expand the current Flood Watch areawide and extend it through 06Z tonight based on the expectation of at least a few more rounds of convection today through late this evening, with this morning`s round likely remaining sub-severe as much stronger convection associated with an MCS shifts from Central into SE TX. By this afternoon, reinforcing upper-level support in the form of a potent shortwave will pivot east along and south of the Middle Red River Valley and induce more robust convection across much of the region. The threat of severe thunderstorms will become more likely during this afternoon and early evening timeframe, owing to MLCAPE around 2000 J/kg and steadily increasing deep-layer shear. This will promote both the threat of damaging wind gusts and even a few tornadoes with some discrete storms possible across mainly the southeast half of the region, where a Slight Risk is outlined in SPC`s Day 1 outlook. Despite some uncertainty surrounding the evolution and coverage of this late day/evening convection, it seemed prudent to carry the Flood Watch through the first half of tonight with a Slight Risk of excessive rainfall in WPC`s Day 1 ERO and an additional 1-3 inches of rainfall possible over the next 24 hours. It probably goes without saying at this point, but CAMs have been of little help with timing and severity of this NW flow pattern convection so can`t rule out additional extensions of the Flood Watch. With that said, higher end PoPs continue through Saturday although rainfall amounts should begin to drop off compared to the past few days. Likewise, the threat of severe thunderstorms looks to decrease as well with less forcing in play behind the departing shortwave trough. Not surprisingly, mild temperatures will persist given the extent of cloud cover and convection over the next few days with highs generally in the lower to mid 80s and overnight lows in the mid 60s to near 70 degrees. /19/ && .LONG TERM... (Saturday Night through Friday) Issued at 236 AM CDT Fri May 31 2024 We don`t fully escape NW flow quite yet for the latter half of the weekend with additional disturbances traversing the Red River Valley SE into our region. This will maintain at least low chance to likely PoPs for Sunday, lower in NW zones and higher in the SE. Expect one more day of below average temperatures before ridging aloft begins to shift closer to the region to start the new work week. This first full week of June should see a return to more average temperatures in the upper 80s to lower 90s and gradually lowering rain chances as the upper ridge becomes more influential through mid-week. Persistent southerly flow will continue through mid-week before a cold front gradually seeps south into the region by late Wednesday into Thursday, enhancing rain chances a bit more during this timeframe. However, it appears the upper-level ridge will be quick to reassert its influence on the region by the end of next week. /19/ && .AVIATION... (18Z TAFS) Issued at 1248 PM CDT Fri May 31 2024 Mix of low, mid and high clouds across the airspace this afternoon following the passage of an MCS to the SW. That being said, light RA continues to work east across the region, while TSRA is present just to the south of KPOE, working north. CAMs have not handled the evolution of the complex very well to this point, a theme that has been ongoing as we remain in this NW flow pattern. This has generated very little confidence in what will occur this afternoon. For now, elected to take an average of each hi-res solution to get some handle on timing and coverage. TSRA/SHRA probs will exist this afternoon, starting to think more for the eastern terminals, before exiting the airspace after 00z-03z, with CIGs tanking overnight. Not ruling out some BR through 12z before CIGs lift and we transition some OVC to BKN after sunrise. RK && .PRELIMINARY POINT TEMPS/POPS... SHV 70 86 74 88 / 40 70 20 40 MLU 69 85 70 87 / 60 80 30 50 DEQ 64 86 67 85 / 30 30 10 40 TXK 68 86 69 87 / 40 50 20 40 ELD 66 85 67 85 / 60 60 20 40 TYR 70 86 72 88 / 20 50 20 30 GGG 69 86 72 87 / 20 60 20 40 LFK 70 87 72 89 / 20 70 10 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...Flood Watch through late tonight for ARZ050-051-059>061-070>073. LA...Flood Watch through late tonight for LAZ001>006-010>014-017>022. OK...Flood Watch through late tonight for OKZ077. TX...Flood Watch through late tonight for TXZ096-097-108>112-124>126- 136>138-149>153-165>167. && $$ SHORT TERM...19 LONG TERM....19 AVIATION...53