HOUSTON — A vigorous Pacific storm system will push torrential rains into Houston Friday night. We will see a widespread 3"-6" rainfall total with some spots seeing greater than 10."
It won't be close to a Harvey so don't worry, but some roads could become impassable.
If this band of heaviest rain falls over the urban center of Houston metro, with all of its concrete and impervious surfaces like parking lots and development, runoff will cause significant street flooding.
The worst weather looks to happen late Friday night into the pre-dawn hours of Saturday. At that point, we may see numerous high water spots resulting in stalled cars. Creeks and bayous will likely rise as well.
In the warmer months, the ground absorbs storm water much faster than in these colder months. This is due primarily to vegetation: in summer it's awake and growing, drinking water hardily. In the cooler months when it all goes dormant, the water simply runs off. For this reason, 10" of rain is much more impactful than it is in the summer months.
This very well could be comparable to the Jan. 18, 2017 flooding across Houston, leaving many roads swamped and many cars stalled.
While it's possible to an forecast the weather, it's impossible to forecast exact impacts. This will be determined by the exact position of the heaviest rain. Based on the history of systems like this, one can make the educated speculation that we are in for at the very least, a high likelihood of nuisance street flooding. At worst, many roads will be impassible late Friday night. Remember: turn around, don't drown. -Brooks Garner, Meteorologist