National Weather Service Forecast for: McKinney TX
Issued by: National Weather Service Dallas/Fort Worth, TX
Updated: 1:26 am CDT Jun 22, 2026
 
Overnight

Overnight: Showers and thunderstorms. Low around 79. South wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
T-storms

 Monday

Monday: Showers and thunderstorms, mainly before 1pm. High near 90. Heat index values as high as 102. Southeast wind around 10 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
T-storms then
Chance
T-storms
 Monday
Night
Monday Night: A 30 percent chance of showers and thunderstorms, mainly between 10pm and 1am. Mostly cloudy, with a low around 77. South southeast wind around 10 mph.
Chance
T-storms
 Tuesday

Tuesday: A 20 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 94. Heat index values as high as 105. South wind around 10 mph.
Slight Chance
T-storms
 Tuesday
Night
Tuesday Night: Mostly clear, with a low around 78. South wind around 10 mph.
Mostly Clear

 Wednesday

Wednesday: Mostly sunny, with a high near 96. South wind 10 to 15 mph, with gusts as high as 20 mph.
Mostly Sunny

 Wednesday
Night
Wednesday Night: Mostly clear, with a low around 77. South wind 10 to 15 mph, with gusts as high as 20 mph.
Mostly Clear

 Thursday

Thursday: Mostly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 20 mph.
Mostly Sunny

 Thursday
Night
Thursday Night: Partly cloudy, with a low around 78. South wind 10 to 15 mph, with gusts as high as 20 mph.
Partly Cloudy
Lo 79 °F Hi 90 °F Lo 77 °F Hi 94 °F Lo 78 °F Hi 96 °F Lo 77 °F Hi 97 °F Lo 78 °F

Severe Thunderstorm Watch
 

Overnight
 
 Showers and thunderstorms. Low around 79. South wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Monday
 
 Showers and thunderstorms, mainly before 1pm. High near 90. Heat index values as high as 102. Southeast wind around 10 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Monday Night
 
 A 30 percent chance of showers and thunderstorms, mainly between 10pm and 1am. Mostly cloudy, with a low around 77. South southeast wind around 10 mph.
Tuesday
 
 A 20 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 94. Heat index values as high as 105. South wind around 10 mph.
Tuesday Night
 
 Mostly clear, with a low around 78. South wind around 10 mph.
Wednesday
 
 Mostly sunny, with a high near 96. South wind 10 to 15 mph, with gusts as high as 20 mph.
Wednesday Night
 
 Mostly clear, with a low around 77. South wind 10 to 15 mph, with gusts as high as 20 mph.
Thursday
 
 Mostly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 20 mph.
Thursday Night
 
 Partly cloudy, with a low around 78. South wind 10 to 15 mph, with gusts as high as 20 mph.
Friday
 
 Mostly sunny, with a high near 98.
Friday Night
 
 Partly cloudy, with a low around 78.
Saturday
 
 Mostly sunny and hot, with a high near 99.
Saturday Night
 
 Mostly clear, with a low around 79.
Sunday
 
 Mostly sunny and hot, with a high near 101. Breezy.

 

Forecast from NOAA-NWS for McKinney TX.