FXUS64 KHGX 181108 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 608 AM CDT Thu Jun 18 2026 ...New AVIATION... .KEY MESSAGES... - The threat for tropical storm conditions has ended as Arthur dissipated. Any lingering coastal flooding will end early this morning. - Dangerous heat will impact southeast Texas through early next week, especially today and Friday. Those planning outdoor activities should prepare for increased heat stress from dangerous heat indices. && .DISCUSSION... Issued at 1204 AM CDT Thu Jun 18 2026 Tropical Storm Arthur is no more as of early this morning, the weakened and elongated surface low now far separated from any organized convection and now shifting away from the area. All Tropical Storm Watches and Warnings have been canceled. Lingering minor coastal flooding is also subsiding as we move past the high tide cycle, and the remaining Coastal Flood Advisory will be allowed to expire early this morning. The next major focus will be increasing heat stress in the wake of Arthur. A lingering soupy airmass, with CAM ensembles supporting dewpoints as high as 80-81F (around 27C) at times and increasing high temps, will support heat index readings in the 108-112F (42-44C) range today and again on Friday. During the overnight, temperatures will only fall to the upper 70s and lower 80s (26-28C) providing limited recovery from the daytime extremes. A Heat Advisory remains in effect through Friday. At least scattered convection will be possible mainly from late Friday through the weekend, though there is at least a chance for a period of greater rain coverage within this time frame. A stalling surface front over the Red River Valley will serve as a focus for convective development Thursday into Friday. While the front will not make it close to our area, some of the resulting storms and outflow from prior storms may move into our area Friday afternoon into Friday night. A few strong storms cannot be ruled out, and there are some guidance solutions showing greater rain coverage persisting Friday night through the day Saturday as well. Scattered convection will remain possible into Sunday, before strengthening mid level ridging increasingly limits rain chances early next week. Outside of interference from clouds/rain, heat stress will continue to be elevated through early next week, with potential for triple digit (38C+) heat indices each day. Additional heat advisories may eventually be needed. && .AVIATION... (12Z TAF Issuance) Issued at 600 AM CDT Thu Jun 18 2026 Mix of CIGS ranging from MVFR to LIFR span across the region this morning. IFR/LIFR most common north/northwest of the Houston area, with MVFR/isolated IFR to the south. Patchy fog/mist has also developed, largely around 2-6 SM for most areas. CIG/VIS should scatter/lift with daytime heating. VFR conditions should return by the late morning/early afternoon with light to moderate southerly winds. Some light showers linger but otherwise conditions should remain dry. Winds ease down slightly in the evening as MVFR CIGs start to fill in from the coast, slightly soon that yesterday/today. Could see another brief window of IFR/lower FLs early Friday morning. 03 && .MARINE... Issued at 124 PM CDT Wed Jun 17 2026 Tropical Storm Arthur will move through the marine zones over the next several hours, bringing winds between 35 and 40kts, with gusts as high as 50 kts. Seas 6 to 9 feet will persist until this evening, with winds and waves subsiding as TS Arther moves inland into SW LA this evening. Onshore flow will become light to moderate by Thursday and persist into the weekend. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 94 80 93 78 / 0 10 30 50 Houston (IAH) 94 81 93 79 / 0 0 10 30 Galveston (GLS) 90 84 90 84 / 0 0 0 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Heat Advisory from 11 AM this morning to 10 PM CDT Friday for TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313- 335>338-436>439. GM...Small Craft Advisory until 9 AM CDT this morning for GMZ330-335- 350-355-370-375. && $$ DISCUSSION...DL AVIATION...03 MARINE...JTC