636 FXUS64 KLCH 121750 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 1250 PM CDT Mon Jul 12 2021 .DISCUSSION... 18Z TAFS && .AVIATION... The MCS that pushed through the area this morning has shifted off to the east leaving VFR conditions across the region. A second, weaker energy wave is pushing into southeast TX at this hour and will likely impact BPT between 18 and 19Z. Should it hold together, convection would move into LCH between 19Z and 20Z. High res guidance shows another disturbance pushing from west to east across the region late this evening. TEMPO groups were added to account for the estimated timing of this disturbance. With the ground once again saturated from the day's rain and light winds expected overnight, patchy light fog will be possible at all terminals during the predawn hours Tuesday. Any fog that develops will dissipate quickly after sunrise. Jones && .PREV DISCUSSION... /issued 935 AM CDT Mon Jul 12 2021/ UPDATE... The MCS that has been pushing through the area this morning will be moving through acadiana over the next couple of hours. Convection within the line has remained sub severe although some gusts to near 40 knots have been noted along the leading edge. A second swath of precipitation approaching the region from the west will need to be monitored for the possibility of training storms especially across areas that already saw heavy rainfall early this morning. The update this morning is just a reflection of the latest obs. No significant changes were made. Jones PREV DISCUSSION... /issued 702 AM CDT Mon Jul 12 2021/ DISCUSSION... For 12z TAF issuance. AVIATION... A line of thunderstorms associated with an outflow boundary from earlier convection is roughly bisecting the forecast area at this time and will continue to dive swd toward the srn terminals over the next few hours. Otherwise, VFR conditions should prevail outside of some temporary MVFR ceilings next hour or so for the Acadiana terminals. Additional diurnal convection will be possible this afternoon with max heating. Some low clouds look possible again prior to sunrise Tuesday, mainly for the srn sites, per forecast soundings. 25 PREV DISCUSSION... /issued 406 AM CDT Mon Jul 12 2021/ SHORT TERM (Today through Wednesday night)... Late night sfc analysis shows the forecast area on the periphery of the Bermuda high while a stationary front was noted to our nw from the Ohio Valley swwd through the Mississippi Delta and ArkLaTex to the TX Hill Country. Water vapor imagery continues to show blocked troffing and a cutoff low over the cntl part of the country, extending swwd to the wrn Gulf Region. Weak vorts rounding the trof have helped fire a series of MCS's, the first one weakening as it approaches the Atchafalaya, and a second also weakening system approaching the nwrn zones. Elsewhere, sfc obs indicate a partly cloudy/warm/muggy night ongoing across the forecast area. In the short-term, all eyes continue on the approaching MCS... radar trends have been showing this feature weakening as it moves into a slightly more stable airmass over the nwrn zones. However recent RAP data shows instability increasing as the system moves farther swd toward the I-10 corridor. Regardless, convection will continue as this feature treks toward the coast through the remainder of the overnight and into the morning hours. WPC is carrying portions of w-cntl LA/interior sern TX in a slight risk for excessive rain through today...luckily so far, no signs of training have been noted with the ongoing convection. As of now, forecast soundings indicate reasonable stabilizing behind this feature which should preclude additional convective development during the early part of the afternoon...however as the low-levels destabilize again with max heating later in the afternoon, some diurnal convection is likely to pop up at that time. Whatever showers/storms that redevelop should dissipate by sunset or shortly after with loss of heating. In addition, latest runs of the HRRR show potentially another convection system moving in from the nw by late afternoon. As we move into Tuesday, the frontal boundary to our nw is progged to drift sewd in response to the mid-level low opening up and pulling the trof axis newd...the front itself likely not getting much closer than ern TX/nwrn LA. Ahead of the front, copious Gulf moisture lingers with forecast soundings indicate MRH values exceeding 70 percent and PWATs aoa 1.8 inches...despite the lack of good forcing mechanisms, daytime heating and any resultant boundaries will be sufficient for setting off more diurnal convection, which should linger again through sunset. By Wednesday, forecast soundings indicate some drier air possibly nudging into the nrn portions of the forecast area which should limit convective development up there. Farther south, our ongoing elevated rain chances linger with POPs bordering on likely being carried across the lower Atchafalaya Basin. 25 LONG TERM (Thursday through Monday)... Extended period starts off with an upper level ridge over the southwest and another off the southeast atlantic coast with an upper level low due north of the Great Lakes. A mid level weakness will extend south down into parts of the MS River Valley. PWs remain elevated in the 1.6 to 2.2 range with daily PoPs around 40 to 60 percent. Most of this will be diurnally driven activity expected in the afternoon. A slight bump in daytime temperatures is expected going through the long term period, however temps will still run below seasonal norms due to cloud cover and rain. Afternoon max temperatures will range from the lower to mid 90s. Overnight will be warm and muggy with temps in the mid to upper 70s and dewpoints matching or falling below by only a few degrees. 87 MARINE... With the area lingering on the wrn periphery of the Bermuda high, mainly light srly winds are expected to persist and no headlines are anticipated on the coastal waters through the period at this time. 25 && .PRELIMINARY POINT TEMPS/POPS... AEX 71 92 74 93 / 50 50 10 20 LCH 76 91 76 91 / 10 40 10 40 LFT 75 91 75 91 / 10 60 10 50 BPT 76 90 76 90 / 10 40 10 40 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$