Leatherman Survival Kit. Free Long Range Weather Forecast for 77493 (Katy), Texas. Katy: 1 active weather warning. For more than 20 years Earth Networks has operated the world’s largest and most comprehensive weather observation, lightning detection, and climate networks. Multiple locations were found. Southeast winds 5 to 10 mph. Calm wind becoming southeast around 5 mph. Partly sunny, with a high near 72. South wind 5 to 10 mph. See weather overview. Hourly Weather Forecast. Increasing clouds, with a low around 40. Today’s and tonight’s Katy, TX weather forecast, weather conditions and Doppler radar from The Weather Channel and Weather.com Katy, TX - Weather forecast from Theweather.com. 5 Day Forecast. Find the most current and reliable 14 day weather forecasts, storm alerts, reports and information for Katy, TX, US with The Weather Network. All NOAA, A powerful storm system will affect the eastern third of the nation into Christmas Day. Toggle navigation. Forecast Discussion . 5pm CST Dec 24, 2020-6pm CST Dec 31, 2020, Excessive Rainfall and Winter Weather Forecasts, Federal Emergency Management Agency (FEMA), National Oceanic and Atmospheric Administration.