Weather in Plano

In Plano, 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 37°F to 96°F and is rarely below 24°F or above 101°F. Based on past studies, the best time of year to visit Plano for hot-weather activities is from late May to mid-September.


The hot season lasts for 3.5 months, from June 2 to September 16, with an average daily high temperature above 87°F. The hottest day of the year is July 26, with an average high of 96°F and low of 76°F. The cool season lasts for 3.0 months, from November 24 to February 24, with an average daily high temperature below 63°F. The coldest day of the year is January 4, with an average low of 37°F and a high of 55°F.


To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered on each day of the year. Plano experiences significant seasonal variation in monthly rainfall. Rain falls throughout the year in Plano. The most rain falls during the 31 days centered on May 16, with an average total accumulation of 4.3 inches. The least rain falls around August 2, with an average total accumulation of 1.6 inches.


A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Plano varies throughout the year. The wetter season lasts 6.2 months, from April 14 to October 20, with a greater than 27% chance of a given day being a wet day. The chance of a wet day peaks at 38% on May 26. The drier season lasts 5.8 months, from October 20 to April 14. The smallest chance of a wet day is 16% on December 31. Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 38% on May 26.


In Plano, the average percentage of the sky covered by clouds experiences mild seasonal variation over the course of the year. The clearer part of the year in Plano begins around May 28 and lasts for 5.5 months, ending around November 13. On October 4, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 73% of the time, and overcast or mostly cloudy 27% of the time. The cloudier part of the year begins around November 13 and lasts for 6.5 months, ending around May 28. On February 24, the cloudiest day of the year, the sky is overcast or mostly cloudy 46% of the time, and clear, mostly clear, or partly cloudy 54% of the time.