Strong storms likely to hit the Houston region Thursday morning: Stage 2 flood alert for areas west of I-45

In brief: Our confidence is increasing in the likelihood of heavy rain across the Houston metro area on Thursday morning, perhaps around sunrise or a few hours later. Flash flooding is possible in the strongest storms.

The overall forecast from the post we published this morning remains more or less on track. However, our confidence is now very high in impactful storms pushing into, and through, the entire Houston region on Thursday morning. Although we still have some questions about timing and placement, it is clear that a serious line of storms will go through.

Tomorrow morning, before dawn, there may be some isolated or scattered showers and thunderstorms across the western half of the Houston metro area. However, the main event is likely to be a line of storms that forms northwest of the region and sweeps into the city. In terms of timing, we think this mass of storms will impact areas such as College Station around 5 am to 8 am, before pushing into central parts of the region (including the area inside Beltway-8/Sam Houston Tollway) between 8 am and noon. After this the line will likely continue down to the coast and exit the area to the east.

The models disagree on where the most impactful rains will be: Brazos County, Montgomery County, or Western Harris County are all possibilities, for example. But the bottom line is that we are going to mix a potent disturbance with an atmosphere with a lot of moisture. This is fertile environment for high rainfall rates, which can quickly back up streets and lead to flash flooding.

As a result of this we are elevating our flood alert to Stage 2 for areas along and west of Interstate 45.

Although we cannot entirely rule out other forms of severe weather, flooding is the main threat from these storms. Most of the region will likely pick up 1 to 4 inches of rain in a couple of hours, but there will almost certainly be higher bullseyes where 5 to 8 inches could fall in a very short period of time. In short, be prepared for disruptions to travel plans on Thursday morning, and be weather aware. We will have a full update for you early tomorrow morning.