FXUS64 KHGX 171845 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 145 PM CDT Sun May 17 2026 ...New DISCUSSION, MARINE... .KEY MESSAGES... - Warm, breezy, and muggy conditions will continue for the next several days. - Isolated light showers possible tonight, scattered activity on Monday, followed by increasing shower and thunderstorm chances for the rest of the week. - Elevated winds, seas, tides, and rip current risk in the marine water and beaches at least into mid week. && .DISCUSSION... Issued at 129 PM CDT Sun May 17 2026 Warm and humid out there, with scattered light showers spreading across the region. Latest observations indicate ample southeast to northeast 925mb moisture transport on top of a broad area of increased theta-e advection. In other words, plenty of moisture is filtering in, enough to support the scattered activity radar is showing this afternoon. This activity should remain low in intensity and is forecast to persist this evening and overnight. Will continue with 15 to 20 percent PoPs during this time frame. Unsettled weather is expected this work week with multiple chances for rain and storms. A deepening and broad longwave trough will be moving over the west CONUS/Rockies tonight into Monday. Ahead of this system, several shortwaves/vort maxes embedded in the southwesterly flow aloft will move over Southeast TX throughout the week. The combination of deep moisture (PWAT values near the daily climatological max) with passing shortwaves (increasing potential vorticity advection) will support scattered showers and isolated storms on Monday, particularly during the peak of daytime heating. The atmosphere becomes more favorable for scattered to widespread activity late Tuesday into the end of the week as multiple mesoscale convective systems (MCS) attempt to move through the region. In addition to the parade of shortwaves aloft, a surface front will attempt to make its way southward across north-central TX sometime in the late Tuesday to Wednesday time-frame. Wherever this boundary sets up will be the main focus for shower and storm activity. Uncertainty remains moderate to high on how far south this boundary will move and where it will likely stall. Latest guidance keeps this front just north of Southeast TX by midweek, stalling somewhere between the Dallas/Fort Worth area and the Brazos Valley through the end of the week. Overall, with plenty of moisture and convergence at the surface, and enough forcing aloft, showers and thunderstorms are expected along of and ahead of this boundary. Localized heavy rain and/or training rain/storms cannot be ruled out, especially along the frontal boundary. At the moment, the highest PoPs are expected on Wednesday with the passage of one of the strongest MCSs. WPC highlights the risk of excessive rainfall with a Slight risk (level 2 of 4) mainly for areas along and north of a line from Brenham to Conroe to Livingston. The mid to upper level pattern continues to look "messy" with several disturbances moving over the region, potentially keeping rain and storm chances in the forecast into next weekend. Forecast rainfall totals from Monday through Friday of 2 to 4+ inches will be possible mainly north of I-10, with isolated higher amounts. Of course, as we have been saying over the past discussions, do not focus on specific rainfall amounts but rather on the potential. It is still early for specific details on the location of the heaviest rain, coverage and total amounts. We will continue to update the forecast as the systems evolve and more Hi-Res guidance comes in. JM && .AVIATION... (12Z TAF Issuance) Issued at 633 AM CDT Sun May 17 2026 MVFR cigs this morning should improve to VFR by afternoon. However, low cigs may linger at the coast all day. MVFR cigs should push inland, impacting most/all terminals by evening and overnight. Winds will be gusty and from the southeast. Gusts are expected to be 20-25 knots. In some areas, gusts could exceed 25 knots. && .MARINE... Issued at 129 PM CDT Sun May 17 2026 Moderate to strong onshore winds and seas from 4 to 7ft (occasionally higher well offhsore) are the main weather story across the Upper TX coast this evening/tonight. A Small Craft Advisory remains in effect through mid Monday morning and could potentially be extended through the evening. Light to moderate onshore winds resume late Monday. Multiple disturbances will be moving across the region through the week; therefore, a daily risk of showers and thunderstorms is expected. The best rain and storm chances will be after mid-week. We will continue to monitor coastal conditions as there remains a high risk of rip currents along all Gulf-facing beaches, as well as a localized risk of minor coastal flooding, particularly during times of high tide. Model guidance now indicates water levels between 3.0 and 3.8 ft MLLW during high tides along the Bolivar Peninsula and Galveston Island through early Monday. A Beach Hazards Statement remains in effect through at least Monday morning. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 89 77 89 76 / 20 20 20 20 Houston (IAH) 89 78 88 77 / 20 20 20 10 Galveston (GLS) 85 79 86 79 / 20 10 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Beach Hazards Statement through Monday morning for TXZ436>439. GM...Small Craft Advisory until 10 AM CDT Monday for GMZ330-335-350- 355-370-375. && $$ DISCUSSION...JM AVIATION...Self MARINE...JM