A sounding rocket is scheduled to liftoff from Wallops Island, VA on May 7th at 7:58 PM. According to a NASA press release, approximately 90 to 100 seconds after liftoff the rocket may be visible from Harris County.
UPDATE: The launch has slipped to Saturday, May 8th at 8:02 PM EDT.
Having never witnessed a Wallops Island launch from Harris County I am a little skeptical of the visibility claim. With the predicted visibility occurring 26.5 minutes before sunset I think the sky will be too bright. And with burnout of the fourth and final stage of the Black Brant XII rocket occurring around 96 seconds I’m not exactly sure what will be visible since there will be no flame or exhaust plume. If something is visible it will appear low on the northeastern horizon.
The press release also mentions an experiment will generate a vapor cloud 9 minutes 30 seconds to 10 minutes after liftoff. Again I think the sky will be too bright to see this, however if it is visible it will appear less than 5° above the eastern horizon.
Referencing my Rocket Launch Viewing Guide, only Dowdell’s Knob will offer a clear view should the launch be visible. However, the posted closing time of the access gate is 8:00 PM so I would not count on this area being available for viewing.