Area Forecast Discussion
Issued by NWS Lake Charles, LA
Issued by NWS Lake Charles, LA
195 FXUS64 KLCH 301839 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 139 PM CDT Wed Sep 30 2026 ...New DISCUSSION, AVIATION, MARINE, FIRE WEATHER... .KEY MESSAGES... -Hot and humid conditions expected through the end of the week with temperatures above seasonal norms. -An upper level ridge will break down by the end of the week allowing for increase in mainly afternoon showers and thunderstorms through Friday. -An increase in the potential for heavy rainfall will come over the weekend as an upper level trough and surface frontal boundary will slowly move into the region and meet up with tropical moisture. && .DISCUSSION... (This evening through next Tuesday) Issued at 134 PM CDT Wed Sep 30 2026 Low level southerly flow will keep a very warm and humid air mass in place for Thursday into Friday. Temperatures on average will be 5 to 10 degrees above seasonal climo norms. A flat upper level ridge will gradually be weakening through the end of the week that will allow for a daily increase in afternoon shower and thunderstorm activity. Over the weekend the strong upper level low over the southwest US will open up into a trough and head east where it will slowly move into the immediate region. A mid and upper level connection to East Pac tropical moisture will move along the trough. Meanwhile, flow around an upper level ridge over Florida will push low level rich tropical moisture from the northwest Caribbean into the region to meet up with the trough. An atmosphere with deep tropical moisture will be found over the forecast area during the weekend. Precipitable Water by Saturday into Sunday will be very anomalously high with values between 2.3 and 2.5 inches, especially southeast of an Alexandria to Lake Charles line. These values are well above the 90th percentile climo value of 1.94 inches and at or above the max moving average. The 100H-50H mean layer relative humidity will be over 80 percent, and with warm cloud layers projected to be around 15k feet depicting good warm rain process, activity that develops will have the potential to be highly efficient precip producers, The question to how widespread any heavy rain will fall will depend on the lift associated with the upper level trough and surface frontal boundary. At this time, guidance is depicting weaker lift that may limit the stronger storm activity and widespread heavy rainfall. However, the copious amounts of tropical moisture has to be respected. There is a 40 to 60 percent chance of greater than 1 inch of rain on both Saturday and Sunday and with 90th percentile rainfall amount totals over the weekend in the 2 to 4 inch range. Therefore, a Slight Risk (level 2 out of 4) Potential or between a 15 and 25 percent chance of seeing excessive rainfall that may lead to flash flooding will be outlined for much of the forecast area for Saturday. At the very least, there is a 60 to 80 percent chance of seeing a wetting rain of over 0.25 inches that will help with fire weather concerns. High temperatures over the weekend will be cooler with highs in the mid 80s due to the cloud cover and rain. A secondary frontal system is expected to move across toward the end of the period on late Monday into Tuesday that is expected to bring drier conditions along with overnight lows in the lower to mid 60s. 07/Rua && .AVIATION... (18Z TAFS) Issued at 134 PM CDT Wed Sep 30 2026 VFR conditions will prevail throughout the period. Winds remain around 10kts with areas along I-10 experiencing gusts up to 15kts through the afternoon and early evening. Winds will weaken to around 6kts after 00z this evening. Showers are possible at all sites after sunrise tomorrow through the end of the period. /86/ && .MARINE... Issued at 134 PM CDT Wed Sep 30 2026 Moderate southeast winds and seas will occur through the end of the week as low pressure will be located over the Plains and high pressure over the southeast US. Over the weekend, widespread rain and storms will impact coastal waters, reducing visibility and causing locally higher winds and waves as a frontal boundary nears the coast. This front may move out into the coastal waters early next week with a period of moderate to strong offshore flow. && .FIRE WEATHER... Issued at 134 PM CDT Wed Sep 30 2026 Hot days with just scattered rain chances will keep vegetation relatively dry through Thursday with increase likely in KBDI numbers and the drought index. However, widespread wetting rain is expected over the weekend that will help reduce fire danger as we move into early October. && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$ PUBLIC/FIRE/MARINE...07 AVIATION...86