Average Weather in Stephenville Texas, United States. In Stephenville, the summers are hot and muggy, the winters are cold and windy, and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 35Â°F to 94Â°F and is rarely below 23Â°F or above 100Â°F.
Due to the moderating effect of the ocean, temperatures are cooler than more inland areas of Orange County, where temperatures frequently exceed 90 Â°F (32 Â°C) and occasionally reach 100 Â°F (38 Â°C). The period of November through March is somewhat rainy, as shown in the table to right.
*Temperature Range is for the Santa Ana Civic Center only. Temperatures will vary somewhat throughout the Orange County with slightly cooler temperatures during the day along the coast and warmer temperatures further inland. Source: National Weather Service & U.S. Naval Observatory.