Climate averages 1991–2020
McKinney weather
in December.
A cool, wet month: the 11th warmest and the joint 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cool month in McKinney: daytime highs average 13.1°C and nights cool to about 4.3°C. By daytime temperature it is the 11th warmest of the 12 months.
Expect about 94 mm of rain on roughly 7 days, which makes December a wet month (the joint 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 10 h 00 min on an average December day.
The nearest other city in this atlas is Allen (12 km away). In December its highs average 13.3°C, about as warm as McKinney, with 91 mm of rain.
Among the 498 cities listed in the United States, McKinney ranks joint 210th of 498 for the warmest December highs and joint 345th of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; McKinney is 2.6°C warmer than that mean.
From December to January, average highs fall by 0.9°C to 12.2°C, and monthly rainfall falls from 94 mm to 70 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
McKinney climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 12.2°C3.0°C | 3.0°C | 70 | 6.8 | 10.210 h |
| February | 14.7°C5.0°C | 5.0°C | 74 | 7.6 | 11.011 h |
| March | 18.8°C8.9°C | 8.9°C | 105 | 9.4 | 12.012 h |
| April | 23.1°C13.1°C | 13.1°C | 118 | 9.1 | 13.013 h |
| May | 27.1°C18.1°C | 18.1°C | 144 | 11.5 | 13.914 h |
| June | 31.2°C22.4°C | 22.4°C | 91 | 9.1 | 14.314 h |
| July | 33.8°C24.8°C | 24.8°C | 50 | 6.2 | 14.114 h |
| August | 33.9°C24.8°C | 24.8°C | 50 | 5.8 | 13.413 h |
| September | 30.0°C20.9°C | 20.9°C | 78 | 6.8 | 12.412 h |
| October | 24.4°C14.9°C | 14.9°C | 104 | 7.9 | 11.411 h |
| November | 17.9°C8.9°C | 8.9°C | 94 | 7.2 | 10.510 h |
| December, selected | 13.1°C4.3°C | 4.3°C | 94 | 7.2 | 10.010 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- Allen in DecemberUnited States · 12 kmHigh 13.3°C · Low 4.5°C · 91 mm rain
- Frisco in DecemberUnited States · 20 kmHigh 13.1°C · Low 4.2°C · 87 mm rain
- Plano in DecemberUnited States · 21 kmHigh 13.4°C · Low 4.6°C · 91 mm rain
- Richardson in DecemberUnited States · 30 kmHigh 13.6°C · Low 4.6°C · 91 mm rain
- Garland in DecemberUnited States · 32 kmHigh 13.6°C · Low 4.6°C · 91 mm rain
- Carrollton in DecemberUnited States · 37 kmHigh 13.7°C · Low 4.8°C · 85 mm rain
- Lewisville in DecemberUnited States · 39 kmHigh 13.7°C · Low 4.8°C · 85 mm rain
- Mesquite in DecemberUnited States · 48 kmHigh 13.9°C · Low 4.8°C · 94 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for McKinney) is explained once on the McKinney year overview and on the Sources, method and limits page.