Area Forecast Discussion
Issued by NWS Shreveport, LA
Issued by NWS Shreveport, LA
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491 FXUS64 KSHV 081726 AAA AFDSHV Area Forecast Discussion...UPDATED National Weather Service Shreveport LA 1226 PM CDT Sat Jun 8 2024 ...New AVIATION... .UPDATE... Issued at 1035 AM CDT Sat Jun 8 2024 No update is needed to the overnight forecast package at this time. /44/ && .SHORT TERM... (Saturday through Sunday) Issued at 257 AM CDT Sat Jun 8 2024 The upper level ridging responsible for the string of days with above average heat across the ArkLaTex will be spending at least one more full day with us before the pattern begins to change. The closed high at the apex of the ridge looks to be passing overhead as we wake up this morning, drifting south and east through the course of the daylight hours today, setting up shop along the Gulf Coast of Louisiana by nightfall, and inducing another afternoon of well above average highs. Based on the performance of today`s temperatures wrt the forecast package, once again trended 1-2 degrees warmer than NBM, placing area sites confidently in the mid to upper 90s by early evening. Meanwhile, as winds become southerly for a more prolonged period, Gulf moisture will filter back into the region, driving up dewpoints and heat indices. "Feels like" temperatures will approach and briefly exceed 100 degrees. While conditions will not meet heat advisory criteria, strictly speaking, conditions are likely to become very uncomfortable, and sensitive and vulnerable groups would do well to use caution in regards to outdoor exposure. Sunday will see the expected regime change begin to take shape in the upper level synoptic pattern. The high will begin to lose its organization as it drifts offshore and the associated upper level ridging flattens out. Meanwhile, ridging over the northern Plains and troughing around a closed low pushing east into the Maritimes will collaborate to return the ArkLaTex to northwest flow. As those who are attentive to our late spring / early summer wx patterns will no doubt know (with no small degree of exhaustion), this regime will favor the return of showers and thunderstorms. However, before the precipitation begins to fall, mostly sunny conditions for most of the day Sunday will allow temperatures to quickly rise from low to mid 70s at daybreak into the low to middle 90s once again my midafternoon. Whether or not any upper 90s reenter the picture will depend both on the speed of intruding cloud cover as well as the effects of the flattening ridge. Based on the margin of time between these contributing factors, elected to split the difference and only trend 1-2 degrees above guidance. /26/ && .LONG TERM... (Sunday Night through Saturday) Issued at 257 AM CDT Sat Jun 8 2024 As promised by the return to northwest flow aloft, a developing low over the southern Plains will have a clear shot to swing a weak surface boundary into the ArkLaTex early next week. The time of arrival for showers and storms has remained rather variable from one forecast cycle to the next, owing to the difficulties models seem to be facing in resolving small scale disturbances in the ambient flow. As of this writing, the consensus of model guidance paints showers and embedded storms as beginning late overnight Sunday into Monday at the earliest for our northernmost zones north of the I-30 corridor. Convection looks to spread south and east through the morning, overspreading in coverage into Monday afternoon and diminishing towards evening. A secondary round as the closed low over the southern Plains begins to work its way east overnight looks to begin for our east Texas zones Tuesday morning, increasing in coverage into the afternoon once again, continuing to exhibit some ebb and flow, but not entirely departing the Four State Region through Wednesday. It is worth pointing out that confidence represented in the PoPs for this activity is not especially high, and the latest runs of long range models waver considerably on the extent and intensity of convective coverage. The upper level low responsible for this unsettled pattern looks to struggle to quickly depart east, broadening out as it drifts towards the Gulf Coast. Guidance attempts to resolve slight chances of precip continuing for our southeastern zones towards the end of the week, though the impacts to the ArkLaTex may be changed significantly by a disturbance attempting to organize itself in the eastern Gulf. Rainfall early in the week will finally break the 90 degree tend, with highs in the 80s expected, gradually warming back towards the 90s by the end of this extended forecast period, with lows dropping into the 60s before climbing back into the 70s throughout. /26/ && .AVIATION... (18Z TAFS) Issued at 1218 PM CDT Sat Jun 8 2024 There are some isolated pockets of patchy MVFR cu ceilings south of SHV at midday as low level moisture tries to work back in from the Gulf. However, most areas (including all TAF sites) are currently VFR with only a few cu with bases of 2.5 to 4.0 kft. Expect a bit more cu as the afternoon progresses, although bases will likely be lifting by ~1 kft during this time period. Surface winds are from the south through southwest at 8 to 15 mph with occasional gusts to or just over 20 mph. Winds will be very light from the south tonight with a better late night moisture surge trying to bring back in some lower stratus into at least southern and southwestern zones around or shortly after daybreak. This low stuff (likely MVFR at at least TYR and LFK) will likely mix out to a greater and more widespread cu field by midday tomorrow in central and western zones. Some minor and temporary MVFR vis reductions around or shortly after daybreak tomorrow are also possible at TYR and LFK. Otherwise, expect mainly VFR conditions to continue in the Four State region through the next 24 hours with winds tomorrow again from the south to southwest with speeds by midday tomorrow ranging from 6 to 12 mph. /50/ && .PRELIMINARY POINT TEMPS/POPS... SHV 98 76 95 74 / 0 0 0 10 MLU 96 73 95 72 / 0 0 0 10 DEQ 93 71 92 67 / 0 0 10 20 TXK 96 74 94 70 / 0 0 0 10 ELD 95 73 95 68 / 0 0 0 10 TYR 96 71 92 72 / 0 0 0 10 GGG 96 71 92 72 / 0 0 0 10 LFK 97 71 94 72 / 0 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...44 LONG TERM....44 AVIATION...50