449 FXUS64 KSHV 191617 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 1117 AM CDT Wed Aug 19 2020 .UPDATE... Satellite imagery from 16z shows mostly clear skies across the area with only a few high clouds moving across portions of the area. Temperatures are ranging from the upper 70s to mid 80s across the area which appears to be on track with our forecast. Look for highs to top out around the upper 80s to lower 90s across the area this afternoon. /33/ && .PREV DISCUSSION... /issued 629 AM CDT Wed Aug 19 2020/ AVIATION... For the 19/12z TAFs, VFR conditions will continue to prevail for the next 24 hours along with northerly or northeasterly surface winds at 10 kts or less. Scattered daytime cu is also likely at most terminals. No precipitation is anticipated. CN PREV DISCUSSION... /issued 337 AM CDT Wed Aug 19 2020/ SHORT TERM.../Today through Thursday/ A surface ridge over the midwest will expand southward across the Southern Plains today. Northerly winds will continue to advect cooler and drier air into the region, which should keep temperatures near or slightly below normal today and Thursday. The flow aloft will also be northerly as the region remains between a large ridge over the Western CONUS and a broad trough over the Eastern CONUS. A weak shortwave trough will move south across the area today, with mainly high cloud cover to accompany it. The trough may strengthen enough to provide some weak vertical ascent for isolated diurnal convection Thursday afternoon. Rain chances will be limited to North Central Louisiana where moisture availability should be sufficient to support precipitation. CN LONG TERM.../Thursday night through Wednesday/ Upper level ridging will remain anchored across the Desert SW Region of the CONUS with a deep longwave trough in place across the eastern half of North America, extending from NE Canada down through the Ohio River Valley, and south into Lower Miss Valley and the Central Gulf of Mexico by the start of the long-term period. Models continue to indicate that a cut-off low will develop across the Lower Mississippi Valley on Thursday and will remain in the region through Saturday. Rain chances will be possible across our eastern zones Friday/Saturday due to their proximity to the upper low. However, with the trough over the region, and the upper low on the eastern periphery of our CWA, deep layer moisture will be limited. Rain chances will be slight and limited to the afternoon during peak heating hours, where the atmosphere is the most unstable. Saturday evening into Sunday, the cut-off low will start to shift northeast into the Ohio River Valley and the aforementioned trough will start to weaken. At the same time, the upper ridge across the Southwest CONUS will expand eastward into the Southern/Central Plains. Much of the region will remain dry on Sunday, but can't rule out some isolated to widely scattered diurnally driven thunderstorms across our southern and southeastern zones, where more instability and low level moisture would be in place due to being on the eastern periphery of the ridge. By Monday, the ridge will start retreat westward, and low-level southerly flow will be on the increase across the region. Sea breeze convection will return to the Louisiana/Texas Gulf Coast and could push northward into our southern and southeastern zones by Monday afternoon, with convection diminishing by sunset with the loss of daytime heating. A similar set-up should play out on Tuesday. However, as move into the middle of next week, we will need to pay very close attention to possible tropical development, as models continue to suggest a system moving into the Gulf of Mexico and possibly towards the Louisiana Gulf Coast by the end of the work week. Rain chances could be on the increase and expand northwestward if this system pans out. With the upper trough over the region through the start of the weekend, less humid conditions will remain as dewpoints will hold in the mid to upper 60s, along with high temperatures in the low 90s. A slight warm up and a rise in humidity values is expected by the end of the weekend into the start of next week, as the trough weakens and deep southerly flow returns to the region. However, not expecting Heat Advisories to return at this time as heat indices should remain below 105 degrees. /20/ && .PRELIMINARY POINT TEMPS/POPS... SHV 92 69 89 69 / 0 0 0 0 MLU 91 67 89 68 / 10 0 20 0 DEQ 88 64 88 65 / 0 0 0 0 TXK 88 65 86 65 / 0 0 0 0 ELD 89 65 87 66 / 0 0 0 0 TYR 92 69 91 68 / 0 0 0 0 GGG 92 68 90 67 / 0 0 0 0 LFK 95 70 93 70 / 10 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 09/20