Area Forecast Discussion
Issued by NWS Shreveport, LA
Issued by NWS Shreveport, LA
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094 FXUS64 KSHV 051529 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 1029 AM CDT Fri Jul 5 2024 ...New UPDATE... .UPDATE... Issued at 1021 AM CDT Fri Jul 5 2024 Today`s high temperatures are going to be contingent on a number of competing factors, specifically developing cloud cover, potential showers and storms, and compressional heating ahead of a surface boundary, coupled with stubbornly high dew points. Based on the heating and moisture observed already this morning, have elected to issue a new Heat Advisory for the southern and eastern portions of the ArkLaTex, including Shreveport, Texarkana, Lufkin and Monroe, in effect until 00Z Saturday, with the possibility of expiring some counties and parishes early as convection develops and heat indices drop off. Otherwise, adjusted PoP grids to reflect the lack of development seen thusfar this morning, allowing for more coverage of convection after 18Z and especially after 21Z as storms manage to fire off. Still only outlooked in General Thunder at this time, but will be monitoring closely, should the isolated storm or two become stronger, potentially producing damaging wind gusts. /26/ && .SHORT TERM... (Friday through Saturday) Issued at 344 AM CDT Fri Jul 5 2024 The short-term forecast period is quite complex, especially over the first 24 hours. Convection is ongoing across Southern Oklahoma just north of the Red River ahead of a cold front. Latest radar loops indicate this convection is weakening, but it is possible that it could survive long enough to move into McCurtain County in Southeast Oklahoma and portions of extreme Northeast Texas around sunrise this morning. Satellite images and surface observations also show an outflow boundary moving southeast away from the convection, and was located very close to the Interstate 30 corridor as of 08z this morning (3 AM CDT). The outflow boundary and cold front should serve as foci for renewed development of showers and thunderstorms today, especially during the afternoon. Convective coverage should be rather widespread, although the stronger storms are still expected to be somewhat spotty. One or two isolated severe storms posing a threat for damaging winds cannot be completely ruled out, but the overall risk is low. The greatest coverage of thunderstorms should be across Louisiana and South Central Arkansas where deep layer moisture will be the greatest. Rain chances should slowly diminish from north to south this evening as the front eventually becomes quasi-stationary south of Interstate 20 in Louisiana and Deep East Texas. Isolated to widely scattered showers and thunderstorms will remain possible along the frontal boundary through the overnight hours. Coverage should once again increase south of I-20 Saturday afternoon during peak daytime heating and as a weak upper disturbance passes over the region. Rain chances on Saturday should be slightly lower compared to today. The rain chances and associated cloud cover makes today`s temperature forecast and potential for high levels of heat very uncertain. I trended several degrees below model guidance as many of the models were still suggesting high temps will be in the mid to upper 90s today. Given the high amount of cloud cover and the high rain chances today, that seemed too aggressive. Dewpoints in the mid 70s to near 80 degrees combined with temps in the lower to mid 90s still yield max heat indices near or above 105 degrees across much of Louisiana. However, based on the arrival time of the highest PoPs this afternoon, heat index values are only expected to be above advisory criteria for only an hour or two. Given this brief time window, we chose not to issue heat headlines today. Daytime high temperatures may be near today`s values again on Saturday, or possibly a degree or two cooler. However, dewpoints should be significantly lower behind the front, which should keep us well below Heat Advisory criteria on Saturday. CN && .LONG TERM... (Saturday Night through Friday) Issued at 344 AM CDT Fri Jul 5 2024 The long-term period is expected to remain rather unsettled with broad upper trough firmly entrenched across the Central CONUS, which will finally slowly move east of the Mississippi River during the latter half of the week. On the plus side, this should keep temperatures significantly cooler than the last week and well below triple digits along with bringing increased chances for much-needed rainfall to most of the area. As the upper trough digs southward into the Central Plains Sunday and Monday, this should push another cold front southwards towards the forecast area. Today`s remnant frontal boundary should move back northwards as a warm front and Sunday but will server as a focus for showers and thunderstorms as a vort max moves across Oklahoma and into the Ozarks. Rain chances are expected to increase for much of next week as the remnants of Hurricane Beryl move north and northeast through Texas and will interact with next week`s cold front. There is still considerable uncertainty regarding the track of Beryl after moving inland in either Northern Mexico or South Texas. This also results in uncertainty regarding the timing for more widespread rain chances. The GFS, which is the faster of the model guidance, suggests this could occur as early as Monday. The ECMWF is a bit later and more into Tuesday. In either case, widespread convection appears likely areawide Tuesday and Wednesday, possibly into portions of Thursday, as what`s left of Beryl weakens and merges with the broad upper trough over the Central CONUS. The moisture-rich tropical system should bring the best chances for widespread wetting rains that we`ve seen in several weeks. It will still be quite humid, but the widespread precip and cloud cover will keep the oppressive heat from returning until well after next Friday. In fact, daytime high temperatures may remain below 90 degrees in most locations for much of the upcoming work week. CN && .AVIATION... (12Z TAFS) Issued at 618 AM CDT Fri Jul 5 2024 A frontal boundary will shift south across the region today bringing VCSH/VCTS conditions to area terminals after 05/21Z. Conditions to improve from north to south with LFK possibly experiencing VCTS conditions as late as 06/06Z. Otherwise, VFR conditions to prevail areawide with possible MVFR conditions near daybreak across LFK. Southwest winds around 5 knots this morning to become northwest today behind the front, then light and variable overnight. /05/ && .PRELIMINARY POINT TEMPS/POPS... SHV 97 77 94 76 / 60 50 40 10 MLU 96 74 92 72 / 60 50 30 10 DEQ 94 69 92 67 / 40 10 10 0 TXK 97 72 94 71 / 40 20 20 0 ELD 93 70 92 69 / 50 20 20 0 TYR 95 75 93 74 / 50 40 40 10 GGG 95 73 93 73 / 50 30 40 10 LFK 96 75 92 74 / 40 40 70 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...Heat Advisory until 7 PM CDT this evening for ARZ070>073. LA...Heat Advisory until 7 PM CDT this evening for LAZ001>006-010>014- 017>022. OK...None. TX...Heat Advisory until 7 PM CDT this evening for TXZ097-112-126-137- 138-150>153-165>167. && $$ SHORT TERM...26 LONG TERM....09 AVIATION...05