Area Forecast Discussion
Issued by NWS Lake Charles, LA
Issued by NWS Lake Charles, LA
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680 FXUS64 KLCH 161738 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 1238 PM CDT Thu May 16 2024 ...New AVIATION... .SHORT TERM... (Today through Saturday night) Issued at 342 AM CDT Thu May 16 2024 Ongoing, poorly forecast, scattered showers this morning has kept any appreciable fog from developing across the region. This development, despite a fairly dry surface to 500 mb layer, will likely persist through the morning as additional moisture advects into the area along an advancing warm front and upper level trof. Precipitation continues to show development in two, somewhat discreet, waves over the next 36 hours. The first will occur as the aforementioned trof traverses the area. PoPs will increase through the day reaching an apex late this afternoon through late tonight as the trof crosses the area. Forecast soundings continue to show PWAT values over two inches supporting the potential for very heavy rainfall. The inherited Flash Flood Watch appears representative and no changes were made to it this morning. WPC has introduced a relatively rare high risk area across Tyler, northern Jasper, and northern Newton counties in Southeast Texas as well as Vernon and northern Beauregard parishes in Western Louisiana. Statistically, 1/3 of all flood related fatalities and 80% of flood related damage occur in areas outlined in high risk areas by WPC. These areas have already seen significant rainfall totals this spring and soils and area waterways remain full so it won`t take but a short duration of heavy rainfall for flash flooding to begin. Expect Flash Flood Warnings to be issued liberally. In addition to the high risk of flash flooding, forecast shear and instability continue to support the development of a few supercells and MCS clusters capable of damaging straight line winds. As with the flash flood threat, this looks most likely across Southeast Texas with the severe risk lessening somewhat across South Central Louisiana primarily because the majority of the convection will be moving across south central LA late tonight into early Friday morning. Damaging winds and large hail appear to be the highest overall threat, but a few tornadoes will also be possible. There`s been a signal within guidance on a lull between the first wave of activity and a second wave associated with a weak frontal boundary that will push through the area Friday afternoon through early Saturday morning. Best estimate right now is that lull will occur sometime from a little after midnight Friday morning through mid to late Friday morning. Keep in mind that while the lull may be noticeable, scattered convection will likely continue across the region even between the two more widespread waves of precip. The second wave poses a slightly lower overall flash flood risk as it will be moving through the region faster, but it does have the potential to exacerbate what will likely be ongoing Flash Flooding from Thursday evening. Storms Friday and Friday night will also have the potential to become severe with damaging winds being the primary threat along an eastward advancing MCS. Guidance has been fairly consistent in maintaining some wrap around moisture across the region through Saturday afternoon so not ruling out the possibility of a few, lighter showers continuing into Saturday morning, but the vast majority of activity should be clear by sunrise Saturday with skies clearing by Saturday afternoon. Jones && .LONG TERM... (Sunday through Thursday) Issued at 342 AM CDT Thu May 16 2024 The main story of the long term continues to be the expected dry weather with warm temperatures as mid/upper-level ridging develops. High temps are expected to mostly run in the lower 90s throughout the long term, while overnight lows are expected to gradually rise to the 70s on account of the increasing dewpoints on a developing srly low-level flow as sfc high pressure moves east of the area. The longer range models are advertising a pair of disturbances crossing to our north towards the end of the forecast period which will attempt to break down the ridging...however as of now, blended guidance continues to keep all rain chances north of the forecast area. 25 && .AVIATION... (18Z TAFS) Issued at 1229 PM CDT Thu May 16 2024 Long duration heavy rainfall will lead to poor conditions across all terminals, this afternoon. VFR conditions will persist through 20Z but will quickly deteriorate down to MVFR/IFR ceilings and visibility. LIFR conditions will also be possible during heavy downpours. In addition to the heavy rainfall severe storms will also be possible starting around 20Z and lasting through sunrise on Friday. Winds in the vicinity of storms will be strong and variable. Background winds will be around 10 knots from the south. && .MARINE... Issued at 342 AM CDT Thu May 16 2024 Widespread showers and thunderstorms will develop across the coastal waters beginning this morning and continuing through Friday evening as a low pressure system moves across the area. Onshore flow will increase to between 15 and 20 knots today as the low approaches increasing seas to 4-5 feet. Winds and seas could be significantly stronger in the vicinity of storms. Winds will weaken by Friday afternoon with seas gradually falling through the weekend. No precip is expected this weekend through next week as light onshore flow prevails. && .PRELIMINARY POINT TEMPS/POPS... AEX 65 83 67 88 / 90 40 40 20 LCH 70 85 72 89 / 70 50 40 20 LFT 72 88 74 90 / 70 50 50 30 BPT 72 86 72 91 / 60 40 30 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...Flood Watch through Friday afternoon for LAZ027>033-044-045- 141>143-152-241>243. TX...Flood Watch through Friday afternoon for TXZ180-201-259>262-515- 516-615-616. GM...None. && $$ SHORT TERM...66 LONG TERM....25 AVIATION...14