Houston, TX 77039 Weather

Key Messages

- Warm and dry conditions expected through early next week.

- Elevated fire weather conditions are possible during the second half of the week.

- Potential change to a wetter pattern by the end of the month.

Discussion

Issued at 1215 PM CDT Wed Oct 21 2026

A coastal trough to our south continues to enhance winds and seas over the Gulf, though not as much as yesterday. LL moisture associated with the system has increased cloud cover in our coastal and southern zones, which may keep temperatures a little cooler this afternoon than we original bargained for in those areas. But generally speaking, we expect most locations to reach the lower to mid 80s. We suspect persistent ridging aloft will keep the weather dry and somewhat warmer than normal through early next week. Highs are expected to average in the low/mid 80s with overnight temperatures dropping into the 50s and 60s. One little wild card will be the strong sfc high that should drift southward from E Canada into E CONUS. We could get a little backdoor front that pushes temperatures downward a few degrees on Sunday and Monday. Also worth mentioning is the low RH values expected Thursday and Friday. Inland values are expected to bottom out in the 25-30% range. These values and light winds should technically keep us out of Red Flag Warning territory. But these very dry conditions warrant a situational awareness of the somewhat elevated fire risk, especially north of I-10.

There continues to be long range ensemble and teleconnection signals of a pattern change around Halloween. These signals are pretty mixed regarding temperature trends. But the signals are moderately strong for a switch to a wetter pattern. One of the signals is the ongoing strong El Nino, which tends to support an active subtropical jet as we head into the colder months. In fact, a quick look at WV imagery shows that we already have a pretty strong subtropical jet that's pushing deep moisture into SW CONUS. Long range guidance (ensembles, deterministic, AI, and non-AI) all suggest a strengthening and potentially amplified subtropical jet pushing in central CONUS by the end of the month or beginning of November. The same data is also suggesting above average rainfall late October - early November. In addition, the MJO is likely to amplify in phases 2 and 3 in 10-20 days, which composites show supporting a wet pattern across SW CONUS and TX (though SE TX is kinda at the eastern edge of the wet anomalies). The MJO signals a potential cool down during this period. But the current long range guidance actually skews a little warmer than normal. ECMWF ensembles (both AI and non- AI) are particularly impressive regarding moisture, with a strong plurality of members showing PWATs over 2 inches around the beginning the November.

So how should we interpret this long range data? First, forecast confidence is always lower in the long range. A lot could change over the next few days, and nothing is set in stone. But second, there is an increasing signal for a stormier pattern starting in about 7-9 days. So I'm comfortable in saying that the odds favor a switch to a wetter pattern. Third, I'm less confident in temperatures. The official Climate Prediction Center forecast during this time frame features a higher chance of above normal rainfall and above normal temperatures.

Self

Aviation

(00Z TAF Issuance) Issued at 545 PM CDT Wed Oct 21 2026

VFR conditions across the area will continue to prevail for another TAF cycle. Winds will relax to LGT and VRB for the overnight hrs. Tomorrow, late-morning winds return to around 5-10kts out of the NE before, the terminals south of 1-10, shift to ESE in the afternoon.

CMW

Marine

Issued at 1215 PM CDT Wed Oct 21 2026

We continue to experience some enhanced E to ENE winds and elevated seas today. However, conditions have significantly improved since yesterday. We expect light to moderate winds averaging from the east through Friday. By the weekend, a stronger easterly fetch is expected to develop across the Gulf. Conditions could reach Small Craft Advisory level by late Saturday or Sunday in the offshore Gulf. The long fetch could make seas the primary hazard. Our forecast is showing offshore seas reaching 6 feet late Sunday into Monday. But considering the potential size of the fetch, the current forecast may be a bit conservative. We cannot rule out offshore seas reaching 8 feet. The fetch is expected to taper by Tuesday, which should bring down seas.