In brief: After a mostly quiet Tuesday, the potential for widespread showers and thunderstorms will increase tonight and into Wednesday morning. Here’s our latest thinking.
This post will only cover the forecast for Tuesday evening through Wednesday morning. However, in the big picture, not much has changed with our forecast through Memorial Day weekend. We still expect periods of widespread and, at-times heavy rainfall. Our Stage 2 flood scale alert remains in effect through that time.
As for tonight, we still do not have great confidence in the finer details of the forecast. But there are a lot of red flags out there, including an atmosphere that is extremely rich with moisture, an approaching (but dying) front, and a fair amount of instability. This, typically, leads to moderate to heavy rainfall. There’s still a chance this could bust, but I do feel as though the region will see some activity tonight.
As a best guess, I think we’ll see a line of storms, possibly broken, form north of Houston roughly along Highway 105 tonight around midnight, or maybe a bit before. This line of storms should then move southward shortly after midnight. Possibly we could see some damaging winds within the stronger storms, but the bigger threat is heavy rainfall. Whether those storms hold together all the way through the Houston metro area and down to the coast is not entirely clear, but that mess should be moving offshore before sunrise.
Even as it does so, another mass of showers and thunderstorms may advance into Houston from the west. Most of our guidance indicates that the threat of rainfall from these storms will be highest along and south of Interstate 10, so basically areas closer to the coast. These storms could reach Houston around sunrise on Wednesday, give or take a couple of hours, before weakening. Or maybe the atmosphere will already be too worked over for them to have too much impact.
Again, there’s a fair amount of guesswork here, but we wanted you to be aware of the potential for heavy rainfall overnight—amounts will vary broadly, from 0.5 inch to 4 inches (maybe) in isolated areas—and into Wednesday morning.
We’ll be back by 7 am with a full forecast for you.
