The pattern across the country toward the later half of this week will be a large high pressure ridge over the eastern states, and a low pressure trough over the western states. With Texas located between these two features, there will be a deep southerly flow of moisture into the area. There is a good potential for a lot of rainfall on Thursday, Friday, and Saturday across Texas. Here's the total rainfall forecast from the National Weather Service through next Monday:
The timing of the end of the rain is a little less certain at this point, with some models being a little faster than others to end the rain. It could linger into Sunday morning, so I have a 40% chance of rain at that time. If this timing holds, it is likely that the race will be dry on Sunday afternoon. I'd put the chances of a dry race at about 75% right now.
If there are significant changes in this forecast through the week, I'll make a new post with an updated forecast. Be sure to follow our Twitter and Facebook feeds for the latest information, or subscribe to our RSS feed.