Keep your umbrellas close the next few days as we're in for more rain. The first batch arrives after midnight tonight and makes for a sloppy Thursday morning commute. It will also make for slow-going for travelers heading east from Houston and west through the Hill Country. There could even be a few rumbles of thunder and rainfall amounts could approach or exceed an inch in many parts of southeast Texas. Here's an estimate from our Super Microcast computer model.
Thursday's rain will be followed by yet more wet weather set to arrive Christmas Eve day. So all of you procrastinating shoppers - beware, you have been forewarned. The good news is that the rain should exit before Christmas Day, but it will be chilly both days. Highs on Saturday may not get out of the 40s!
It's all being caused by a series of upper-level disturbances moving in from Southern California in the past few weeks. This is a pattern that has developed since Thanksgiving. Here's an image of the satellite picture that enhances the water vapor in the atmosphere; it shows the disturbances indicated by an "L".
Like a conga line, they've been moving along the path of the jet stream, indicated by the arrows. The pattern may break down a bit heading into the last week of 2011.