782 FXUS64 KSHV 210600 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 1200 AM CST Thu Feb 21 2019 AVIATION... For the ArkLaTex, VFR with a light NW bump at times, but most sites are flat calm already with frost N of I-20 toward dawn until the clouds roll in. Climb winds are NE up to 2kft then back to W/SW increasing speeds from 20-100KT by FL320. VFR lowers to MVFR/IFR into the aftn hrs as rounds of shwrs/isold TS affect all terminals up to and along I-20. SFC winds bcmg ENE5-15KT with an arc of activity rotating NW off the Gulf. VFR not again until midday saturday with another heavy round fri late into Sat. /24/ && .PREV DISCUSSION... /issued 1017 PM CST Wed Feb 20 2019/ UPDATE...To lower a few lows and add some patchy fog. SHORT TERM... Mid to upper 30s N and low to mid 40s South. We did need a little breathing room on lows at a few sites, but limited changes will be noted on text zone products other than the addition of the patchy fog from S AR into N LA through about daybreak. Cirrus will increase and lift fog early with slightly warmer temps perhaps. /24/ PREV DISCUSSION... /issued 405 PM CST Wed Feb 20 2019/ SHORT TERM.../Tonight through Thursday Night/ Morning clouds have given way to a pleasant afternoon as drier air has filtered in behind our recently departed cold front, allowing for mostly clear skies and ample sunshine with high temperatures warming into the 50s. However, this brief reprieve from the rain is not expected to last much longer as clouds will eventually creep back northward overnight through early Thursday as SW flow aloft prevails. Overnight temperatures will fall quickly after sunset with lows in the 30s to lower 40s by daybreak on Thursday. As clouds begin to return across our southern zones, isolated to scattered convection will encroach on our far southern sections after midnight through daybreak. Convection will continue to expand northward through Thursday as moisture advection increases with the recent cold front stalling to our south, gradually lifting back northward Thursday afternoon through Thursday night with showers and thunderstorms becoming more widespread across much of the region. With increasing cloud cover and rain expanding north, temperatures will only manage to climb into the lower to mid 50s for highs on Thursday afternoon and then only fall back into the mid to upper 40s Thursday night. /19/ LONG TERM.../Friday through Wednesday/ As the next upper trough begins to reload Friday morning across the Desert SW and Nrn MX, an gradually increasing Srly low level flow will allow in a warm front to begin lifting NNW into Deep E TX/Ncntrl LA throughout the day, with areas of SHRA and possibly a few embedded TSRA continuing to expand N across NE TX/SW AR/SE OK. General agreement amongst the short term progs suggest a cluster of convection along/just N of the warm front over portions of E TX/N LA/Scntrl AR, such that pops have been raised to categorical Friday for these areas, with a gradual increase to likely pops by afternoon for areas N of the I-30 corridor of NE TX/SW AR. QPF amounts of 1-2 inches will be possible Friday morning through early Saturday over SW AR/extreme Nrn LA, but rain rates should be low enough within the stratiform rains to negate a flash flood threat through this time. Shortwave energy embedded in the deep SWrly flow aloft ahead of the reloading trough should keep the convection going Friday night over the Nrn half of the region near and N of the warm front, but appears to diminish in intensity after 06Z Saturday as we await for large scale forcing to increase ahead of the ejecting upper trough that will take on a negative tilt once it crosses the TX Panhandle into NW OK. The warm sector S of the warm front should continue to expand N into SE OK/Wrn and Srn AR by Saturday morning, with H700-500 lapse rates increasing to 8-8.5C/km beneath and just ahead of the ejecting trough axis near and ahead of the attendant dry line. Ample bulk shear and SBCapes of 800-1200 J/Kg near and just ahead of the dry line within the warm sector should yield an increasing line of strong to severe convection E of the I-35 corridor by/shortly after 12Z which will rapidly translate E into the region by mid to late morning. The GFS even suggests the H850 jet increasing to 60-65kts by 15Z Saturday over extreme Ern TX/Wrn LA/SW AR which would help to maintain or even strengthen this convection despite the elevated lapse rates and SB instability diminishing slightly through mid to late morning across the area. Damaging winds and isolated tornadoes appear to be the primary threats, although small hail and brief heavy rainfall would be possible in the stronger storms as well. Any flash flooding threat appears to be brief and localized with the progressive squall line, primarily over SW AR/portions of N LA. Much drier air will advect E with the dry line passage from late morning through the afternoon, but gusty winds to 35-40 mph will be possible over at least the Wrn half of the region before the pressure gradient weakens during the evening as the trough's attendant cold front rapidly progresses SE through the area. Should see a return to seasonal temps Saturday night with the cold fropa, with dry conditions expected to round out the latter half of the weekend into much of Monday. The 12Z ECMWF/GFS have really backed off on the potential for overrunning early next week, with the ECMWF actually dry over all a of our region through at least mid-week. Have trimmed back pops Monday to slight chance just over Deep E TX/Wcntrl LA as a consensus with the Canadian, but did keep chance pops going Monday night and Tuesday mainly along/S of the I-20 corridor per the GFS/Canadian solutions. Did drop pops for the end of the extended as a cold fropa is progged to advect drier air back S into the region. /15/ PREV DISCUSSION... /issued 1233 PM CST Wed Feb 20 2019/ .PRELIMINARY POINT TEMPS/POPS... SHV 38 52 46 64 / 10 80 80 80 MLU 40 52 48 69 / 10 90 80 80 DEQ 31 56 44 55 / 0 20 40 70 TXK 35 53 44 57 / 0 50 60 70 ELD 34 52 45 61 / 0 80 80 80 TYR 39 54 46 63 / 0 50 50 80 GGG 37 53 46 63 / 0 60 60 80 LFK 41 53 50 72 / 20 80 70 70 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && 24/19/15