PHOENIX — You hear a lot about temperatures being above average or below normal during a weathercast, but what does that really mean?
12News Meteorologist Ginger Jeffries breaks down the terms so they are easy to understand.
Average daily temperature
The average daily temperature is determined by taking the highest and lowest recorded temperature on any given day and then dividing it by two.
Average high and low
This is different than the average high temperature or average low temperature.
For the average daily high, we take all the high temps recorded on that day and divide by the number of years recorded.
The same process is used for factoring the average daily low.
Normal temp
The normal temperature is a little more general. If the average high for a day is 80 degrees, anything within 5 degrees warmer or cooler is considered normal.
In colder climates, during the winter, that span is increased to 10 degrees warmer or cooler due to the extremes of winter.
Collecting data
Official weather data for these records began in 1872.
By 1904, principal records of marine observations were started by the National Climatic Data Center, which was formerly called the National Weather Records Center.
Notable records
Some notable records for Arizona include the hottest temperature recorded in Phoenix, 122 degrees on June 26, 1990.
The hottest temperature recorded for the state was at Lake Havasu, 128 degrees on June 29, 1994.
Last summer, in 2023, from June 30 through July 30 we had the longest stretch of 110 degrees or greater. The Valley saw a total of 54 days that were higher 110 degrees.
We have also had accumulated snowfall in Phoenix, on the dates of Jan. 20, 1933 and Jan. 21, 1937. Small dustings of snow happen more often.
The coldest recorded day was 16 degrees on Jan. 7, 1913.
The largest amount of rain in a single day was Sept. 8, 2014, with 3.29 inches.
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12News+ showcases live video throughout the day for breaking news, local news, weather and even an occasional moment of Zen showcasing breathtaking sights from across Arizona.