FXUS64 KHGX 211136 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 636 AM CDT Sat Mar 21 2026 ...New AVIATION... .KEY MESSAGES... - A strong heat dome over the Southwest will keep temperatures well above average through the weekend and persist next week. - Persistent southerly flow will bring areas of fog late at night and into the early mornings. Some of this fog could be locally dense, especially for areas along and south of I-10. && .DISCUSSION... Issued at 1147 PM CDT Fri Mar 20 2026 Fair weather conditions will prevail tonight along with southerly winds at 5-10 mph. Low temperatures will be in the upper 50s to lower 60s inland and the mid 60s along the coasts. Tranquil but warm conditions will prevail throughout the next several days. A persistent mid-level high remains anchored from the southern portions of the Southern Plains to northern Mexico. Our temperatures this weekend and next week will unfortunately remain well-above average, roughly about 10-15 degrees above on a daily basis for this time of the year. The highs will fluctuate between the upper 80s to lower 90s inland and the mid to upper 70s along the coasts. Day to day variations of whether most areas will be under the upper 80s range or the upper 80s to lower 90s range will depend on how strong the mid-level high is along with how much moisture moves across Southeast Texas. For example, the high will be stronger and moving closer to western Texas Friday and Saturday. Combined with sunny skies and slight surges in moisture we will likely see highs in the upper 80s to lower 90s range. By early next week, a weak mid-upper level shortwave will move across Texas while a mid level low meanders near the western Gulf waters. The high will then weaken and shift closer into the Baja California and western Mexico region and a weak cold front moves into central TX and stalls. This will lead to slightly cooler temperatures for us, with the highs mainly in the mid to upper 80s Monday and Tuesday. By mid week, the low over the Gulf weakens as it moves into the central Gulf waters and the high will once again build and move into its previous position (over northern Mexico). In addition, a surge of low level moisture is expected, rising PWs to 1.0-1.2 inches. Our highs will increase back into the upper 80s to lower 90s on Wednesday and Thursday. Apart from the above average temperatures, we will have the potential for the development of fog during the overnight to early morning hours during the next few days. Fog is expected to burn off shortly after sunrise. Cotto && .AVIATION... (12Z TAF Issuance) Issued at 631 AM CDT Sat Mar 21 2026 MVFR ceilings and vis at a couple terminals this morning, but thanks to the slightly elevated winds there has not been much in the way of fog. Conditions will improve even further after sunrise with any light fog around burning off. The winds will stick around today, with a few gusts around 20kts possible at most terminals around mid day into early afternoon. Very similar conditions can be expected tonight into early Sunday with winds remaining slightly elevated once again. && .MARINE... Issued at 1147 PM CDT Fri Mar 20 2026 Light to moderate southerly to southwesterly winds and seas of 2-4 feet are expected through the weekend. Light southeasterly winds are then expected Monday into Thursday along with seas of 1-3 feet. Conditions will remain dry, but areas of sea fog is possible over the bays and nearshore Gulf waters generally from evening to late morning hours. Cotto && .FIRE WEATHER... Issued at 1147 PM CDT Fri Mar 20 2026 We will need to keep an eye on the fire weather conditions this weekend, in particular during the afternoon hours as afternoon RH values drop in the 30-40 percent range and southerly winds range around 10-15 mph. Cotto && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 90 61 90 60 / 0 0 0 0 Houston (IAH) 88 63 89 63 / 0 0 0 0 Galveston (GLS) 77 66 77 66 / 0 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Cotto AVIATION...Self MARINE...Cotto