Climatology 101: 37th warmest, 52nd wettest July on record


A late thunderstorm saved Tucson from one of the drier months of July in recent memory.

Thanks to 1.49″ rain at Tucson International Airport on the 28th, July 2015 goes down as the 52nd wettest on record. Casa de Beamish in Oro Valley picked up 0.91″ rain in July. Odd to see the airport get more than yours truly.

Tucson’s average temperature sat a shade above 87°, good for the 37th warmest July since 1895. Interesting to note the lack of true Summer heat last month. For the first time in 40 years, Tucson did not record a daytime highs at/above 104°.

Below is the full July 2015 climate recap, compiled by the great meteorologists at NWS Tucson.

The beginning and end of July saw your typical monsoon weather pattern with scattered afternoon and evening thunderstorms, some producing strong gusty winds, blowing dust and heavy rain. The remainder of the month saw the upper level winds, normally out of the east and southeast, being from the west and southwest. Due to this upper wind pattern, most of the month saw hit and miss storms. The airport was running well below normal on rainfall until the 28th when 1.49″ of rain was recorded. This ranks as the 14th wettest July day at the official recording spot for Tucson.
A third tropical storm to impact the area in the past two months as moisture from Hurricane Dolores moved into the area on the 17th & 18th. There were hopes that periods of moderate to heavy rain would move across the metro area. In fact a flash flood watch was issued for those two days. However due to thick cloud cover and storms being on the periphery of the metro area, the now infamous rainfall “donut hole” occurred over Tucson. The image on the right, which was posted on our Facebook page, shows the “donut hole” very clearly. (Click on image for larger view) July 2015 "rainfall donut hole"
Temperature extremes for the month ranged from a high of 103° on the 12th & 28th to a low of 71° on the 1st. This is the first July since 1975 and the 7th July overall (1897, 1914, 1919, 1962, 1974 & 1975) that the hottest monthly temperature wasn’t 104° or hotter. The monthly average temperature of 87.3° was slightly above normal and ranks as the 37th warmest on record, tied with 1901, 1915 & 1928. Once again the average monthly temperature was driven by the daily lows. The average low temperature of 76.3° ranks as the7th warmest on record, tied with 1996. On the high temperature side, the average high temperature of 98.3° was cooler than normal, by almost 1.5°, and ranks as the 40th coldest on record. No daily records were set during July for the first time since 1999.
July 2015 daily high temperature departure from normal July 2015 daily low temperature departure from normal
Click on image above for larger view
Rainfall across the metro area, using several sources like and the Pima County Regional Flood Control District gauges, varied widely from 0.25″ to 3.50″. The International airport, which is the official recording location for Tucson, recorded 2.08″ which ranks as the 52nd wettest July on record.
July 2015 stats
Average high temperature
– 1.4°
Average low temperature
+ 1.9°
Average temperature
+ 0.3°
Days with highs 100° or greater
– 3
Days with highs 105° or greater
– 8
– 0.17″

When did daily high/lows occur?
Average high temperature time
3:21 pm
3:47 pm
26 min. early
Average low temperature time
5:49 am
5:46 am
3 min. late
Average times based on data collected from 2001-2014

One thought on “Climatology 101: 37th warmest, 52nd wettest July on record

  1. love these graphics. escaped SE Ariz to come to the wet state of Ark. only to find them in their worst draught in years. no rain, just 100 degrees and high humidity. im heading back to AZ where at least its “a DRY heat’. lol

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