textproduct: Houston/Galveston

KEY MESSAGES

- Negative tide levels are are expected to persist on Matagorda and Galveston bays, making navigation - especially in the upper portions of the bays - more difficult through the early part of this week.

- Confidence is now quite high in the potential for rainfall across Southeast Texas, but particularly at the coast, mid-week, with a focus on Wednesday. Average rainfall ranges from an inch or more at the coast, to 0.25-0.5 inches well inland.

- Expectations around a more significant cold front next weekend are beginning to take shape. Confidence is growing sharply in the potential for a strong push of cold air into the area. There is less confidence in specific details beyond that, and it will be wise to monitor the forecast through the week as we analyze potential impacts to Southeast Texas.

DISCUSSION

Issued at 1242 AM CST Mon Jan 19 2026

For now, we continue our see-saw around seasonal averages across Southeast Texas. Today had fair weather, while temperatures were a little on the cool side of average. Light onshore flow has returned, and with a mostly sunny sky continuing, tomorrow looks to make its way a little on the warm side of average (with the exception of perhaps Crockett and other areas north of Lake Livingston, more on that in just a tick).

While most of our area will be enjoying a seasonably mild day Monday, our next cold front will be making its way towards the area. For most of us, it will come too late to chop down temperatures in the afternoon...and if anything may boost them slightly through southwest flow ahead of the front. But the far, northernmost portions of our area may only get to around average for late January before the front moves through. And when it comes to direct impacts from this weak front, that's really about all there is to say about it.

No, the real impact from this front comes after it's made its way through the area, stalled out, and its remnants become a coastal trough that makes its way back northward into mid-week. This will keep winds easterly to southeasterly, pumping in a modestly warmer, and decidedly more humid airmass into Southeast Texas. Eventually, a shortwave trough aloft will make its way across the region, creating a focus for rainfall development on the coastal trough. Rain chances should begin to emerge as early as Tuesday evening, with potential for lingering showers as late as Thursday. However, Wednesday looks to be the prime time for rainfall development at this time.

Of course, with an event built by a shortwave trough and a fairly subtle shortwave trough, there are going to be a lot of fine details driven by timing and placement that we just can't skillfully forecast this far out...and sometimes not until we're heading into the event. But from this vantage, rain chances look high on Wednesday across Southeast Texas, but especially so towards the coast, closer to the better moisture pool and the surface focus for convection. Similarly, rainfall totals in general should be higher over the coast and nearshore Gulf waters.

That we're managing much rain at all is a little bit impressive given that precipitable water values across the area are below the 10th percentile. Yet, both the NAEFS and Euro ensembles bring PWATs to the 90th percentile near the coast by Wednesday afternoon. Though, in fairness, this time of year that's roughly exceeding 1.25 inches. Not an extreme amount on our absolute scale, but quite high for late January. As such, I'd expect some good rain, especially near the coast, but nothing overly concerning at the moment. Most flooding concerns should be limited to localized spots should we manage to get a good convective hotspot. The Euro ensemble's Extreme Forecast Index does rise above 0.5 along the surface trough Wednesday right along our coast, so there's at least some suggestive waggling of eyebrows towards locally heavy rain, even if not terribly compelling. The current forecast paints an average around or above an inch along the coast, then gradually decreasing inland until you get to the 0.25-0.5 inch rage as an average at such locations as Caldwell, College Station, Madisonville, and Crockett. This rough pattern should hold, the main question would be how much it slides farther inland or towards the Gulf, changing where locations land on the gradient.

After that coastal trough makes its way off, things chill out for a little bit, as we head back to a warming trend and decidedly above average temperatures for most of the area Thursday and Friday. And then...then we get to the weekend.

Hoo boy, I could write more than the rest of this AFD combined on the weekend if I really wanted to. But...for a Day 5+ forecast, it is likely not wise to get too deep into it. But let's wade in the shallow end for a bit, get used to the water temperature before we really dive deep in the days to come. The thing that stands out at me the most is how quickly the whole suite of model guidance has come into agreement on a very strong arctic cold front pushing into the US, and through our area this weekend. At this range, usually there is some amount of fuzziness even in broad details, but these broad details are practically unanimous. Pick pretty much any deterministic model, ensemble set, whatever - this gon' be a strong front! In addition, you can look at the progs for just about any of the more transient teleconnections you want (MJO, NAO, Arctic Oscillation, pick your favorite!) and all seem to support a surge of cold air deep into North America. One other nice thing that models seem extremely in sync on - that the coldest surge of arctic air will be hemmed farther north and more to the east, focused more on my homeland, the Great Lakes. But...even a glancing blow from a big arctic surge can be powerful.

Even as we start to get beyond the broad strokes, model consensus is holding up better than I might expect for this time frame. I can say with about as high of confidence as I can that this will be a strong front. And as the shift partner and I have been chewing things over (and he is a teleconnection/beyond-our- forecast-period guru), we're reasonably confident this will make a push for being one of, if not the, coldest airmass of this winter. I've found this collection of evidence to be strong enough that I'm willing to include mentions of a slight chance of freezing rain north of the Houston metro on Saturday and Sunday nights. Just the concept of me being so comfortable putting even something as little as "slight chance" for wintry precip in the forecast at Days 6-7 surprises me a little.

And here is where we really start to get into more speculation than strong evidence, and where I would prefer to stop, because speculation is not what we do here. So, for right now, I really like this three-point framework my shift partner summed our conversation up with: - We are *highly confident* that a strong cold front moves through the area this weekend. - It is *plausible* that this will be one of the coldest airmasses of the winter. - It is *possible* that we see frozen precipitation somewhere in our portion of Southeast Texas. But there is too little confidence to say anything more detailed at this time.

AVIATION

(12Z TAF Issuance) Issued at 543 AM CST Mon Jan 19 2026

VFR conditions prevail through the period. Winds will be light and variable this morning, becoming SE around 5-10 kts this afternoon Gusts to above 15 kts will be possible after 20Z due to enhanced sea/bay breeze.

MARINE

Issued at 1242 AM CST Mon Jan 19 2026

The Low Water Advisory now continues through Monday's low tide cycle on both bays, and has already been extended through Tuesday's low tide cycle for Galveston Bay. On both bays, the most severe conditions are expected to be on the upper portion of the bay. Despite the return of onshore winds, water levels continue to lag below astronomical tides, which are already very near the low water advisory threshold. Eventually, more persistent onshore mid-week should bring enough improvement that advisories may no longer be necessary. However, less severe negative tides can be expected to linger deep into the week.

Along with the onshore flow becoming more established in the middle of the week, expect rougher marine conditions as well as widespread rainfall as a coastal trough moves through. Small craft will likely need to exercise caution during this period. Finally, a much more significant cold front is anticipated next weekend. It will be necessary to monitor the forecast through the week as we build more confidence in the specifics of timing and impacts to area waters.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 65 39 61 51 / 0 0 0 30 Houston (IAH) 66 43 63 54 / 0 0 0 30 Galveston (GLS) 62 53 62 57 / 0 0 0 30

HGX WATCHES/WARNINGS/ADVISORIES

TX...None. GM...Low Water Advisory until 6 PM CST this evening for GMZ330.

Low Water Advisory until 10 PM CST Tuesday for GMZ335.