Climate averages 1991–2020

Surprise weather
in December.

A mild, fairly dry month: the coolest and the 10th driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 17.5°C Daytime mean, December
Average low 4.9°C Night-time mean, December
Rainfall 31 mm 3 days with ≥1 mm
Daylight 10 h Sunrise to sunset, per day
Every month in Surprise · average highYear overview

December is a mild month in Surprise: daytime highs average 17.5°C and nights cool to about 4.9°C. By daytime temperature it is the coolest month of the year.

Expect about 31 mm of rain on roughly 3 days, which makes December a fairly dry month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 9 h 58 min on an average December day.

The nearest other city in this atlas is Peoria (Arizona), United States (10 km away). In December its highs average 17.7°C, about as warm as Surprise, with 25 mm of rain.

Among the 498 cities listed in the United States, Surprise ranks joint 88th of 498 for the warmest December highs and joint 53rd of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Surprise is 7.0°C warmer than that mean.

From December to January, average highs rise by 0.8°C to 18.3°C, and monthly rainfall rises from 31 mm to 35 mm.

The annual picture

December in context

30-year average
Average highAverage low°C
Average daily high and low temperatures by month The same values are available in the monthly table below. Lines show mean daily maxima and minima, not a forecast interval. 051015202530354045 JanFebMarAprMayJunJulAugSepOctNovDec

Monthly rainfall

Average total · mm
Average monthly rainfall totalsEach bar is a mean monthly total over 1991–2020. Full numbers are in the table. JanFebMarAprMayJunJulAugSepOctNovDec 500

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Surprise climate table

1991–2020
Monthly climate averages for Surprise, 1991–2020
MonthAverage highHigh / lowAverage lowRainfall mm/monthRain days ≥1 mm/dayDaylight hours/dayDay­light h/day
January 18.3°C5.0°C5.0°C353.610.210 h
February 20.1°C6.5°C6.5°C414.311.011 h
March 24.3°C9.6°C9.6°C273.112.012 h
April 28.8°C13.6°C13.6°C8.61.313.013 h
May 33.7°C19.1°C19.1°C3.30.713.914 h
June 39.2°C24.4°C24.4°C1.70.314.314 h
July 40.4°C28.1°C28.1°C173.014.214 h
August 39.4°C27.6°C27.6°C233.813.413 h
September 36.6°C23.4°C23.4°C203.112.412 h
October 30.4°C16.3°C16.3°C182.111.411 h
November 23.4°C9.6°C9.6°C212.210.510 h
December, selected 17.5°C4.9°C4.9°C313.410.010 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

Distance from Surprise

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 limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Surprise) is explained once on the Surprise year overview and on the Sources, method and limits page.