FXUS64 KHGX 202342 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 642 PM CDT Fri Mar 20 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 127 PM CDT Fri Mar 20 2026 Dry and unseasonably warm conditions will persist across the region through the weekend as a robust mid to upper level ridge remains anchored over the Southwestern CONUS. This feature continues to provide strong subsidence, effectively suppressing precipitation and boosting afternoon temperatures well above late March climatological norms. At the surface, high pressure to our east will maintain a steady southerly flow, ushering in a warm and moist airmass. Guidance remains consistent with 850 mb temperatures into the 18-21 degC range. This thermal profile translates to surface highs into the upper 80s to low 90s, particularly across the Brazos Valley. While the probability of exceeding 90F diminishes slightly as you move eastward (east of I-45), much of the area will still see temperatures in the mid 80s over the next several days. With persistent onshore flow and decent low-level moisture, radiation fog is expected to develop during the late night and early morning hours through at least Sunday. Some areas may see locally dense fog, with the highest probabilities focused along and south of the I-10 corridor. The upper-level ridging will flatten slightly early next week in response to a weak and dry cool front. Models suggest this boundary will approach the region on Monday before it begins to retrograde and stall just north of the area. No significant impacts or airmass changes are expected...the forecast remains dry and warm. The ridge aloft is forecast to strengthen and shift/expand further east into our area, reinforcing the dry pattern and increasing temperatures to well-above normal. && .AVIATION... (00Z TAF Issuance) Issued at 642 PM CDT Fri Mar 20 2026 VFR with gradually decreasing southerly winds this evening. After about 5z, look for some patchy fog development along/south of the I-10 corridor. Outside of the usual trouble spots (LBX, SGR, CXO) the overall coverage and lowest cigs/vsby should peak in the 9-13z timeframe. SREF guidance, which handled things pretty well last night, is depicting a swath of potential IFR/LIFR conditions from roughly Edna-Sugarland, then another from about Lake Houston ENE across Liberty Co and into La. The I-45 corridor in between those two encompass the metro terminals, so there is a bit more uncertainty there. Plan for now is to advertise lower end MVFR conditions there, but with some placeholders (SCT005-SCT009) should things take a more pessimistic turn. Otherwise, fog should burn off fairly quickly after sunrise and things should trend back up to VFR areawide in the mid morning hours Sat. SSW winds will gradually increase to 10-20kt in the late morning & afternoon hours. Appears to be a rinse/repeat scenario Sat night. 47 && .MARINE... Issued at 127 PM CDT Fri Mar 20 2026 High pressure centered over north-central Gulf will continue to bring light to occasionally moderate onshore winds S to SSE) and low seas over the next several days. Seas will generally remain into the 1 to 3 ft range, occasionally up to 4 ft during the weekend. Rain is not anticipated, but areas of fog will be possible in areas adjacent to the bays and the islands early in the mornings. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 59 91 61 91 / 0 0 0 0 Houston (IAH) 62 89 64 89 / 0 0 0 0 Galveston (GLS) 66 77 67 78 / 0 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...JM AVIATION...47 MARINE...JM