* Updated Monday, September 18, 2023 3:27:59 pm Martinsville time - Weather by CustomWeather, © 2023. Forecast for the coming week for Martinsville, shown in an hour-by-hour graph. Mostly Clear Low: 61 °F Wednesday Mostly Sunny High: 86 °F Wednesday Night Mostly Cloudy then Chance Showers Low: 64 °F Thursday Showers Likely High: 73 °F Thursday Night Showers.