Climatology 101: The Autumn with no chill

It was almost as if Autumn never arrived in the Sonoran Desert.

jeff-2015-monthly-climate-icons

Tucson’s average temperature last month checked in at a balmy 64°, good for the 6th warmest November on record. Add September and October to the equation and Tucson finished with its warmest Autumn on record. The average temp of 74.1° barely eclipsed the old record of 74° set in Fall of 1999.

Not helping matters was the abnormally long warm streak in October. Tucson reached 90°+ 18 straight days (5th longest) and registered the latest 97° day on record. October 2016 also became the 5th on record to not have a daytime high cooler than 80°.

The National Weather Service reports this Fall was the first in four years to record below average rainfall in Tucson. 2.20″ rain fell between September 1st and November 30th, which is over a half inch below normal for the season. The once lofty yearly rainfall surplus we entered September with has shriveled up. As of December 1st, TIA was running a mere 0.07″ above normal for rainfall in 2016.

Here is the complete climate report for November & Autumn 2016 from the fine folks at NWS Tucson:

Coming off the warmest October on record, Tucsonans were hoping that the last month of the Fall season would usher in cooler temperatures. Unfortunately most of November recorded well above normal temperatures and if it wasn’t for the rather cool end of the month, November 2016 would’ve been ranked in the top 5 for warmest November.
The month started off with high temperatures in the lower to mid 80s before a Pacific weather system brought scattered showers, isolated thunderstorms and pea size hail to the area on the 3rd. High temperatures ranging from the mid 70s to mid 80s continued across the area through mid-month. Then stronger high pressure aloft brought warmer temperatures with the airport threatening the 2nd latest calendar 90° high occurrence on record on the 15th. The high temperature end up being 89° on the 15th which tied that dates record high previously set in 1906 & 1999. Dating back to 1894, the average last 90° high in the calendar year occurs around October 20th.
A Pacific weather system on the 17th brought much cooler temperatures with highs being 18-20 degrees cooler than what occurred on the 15th. The low temperature on the 18th of 42° was the first below normal low temperature that the airport recorded since October 12th.
High temperatures quickly rebounded back into the lower to mid 80s on the 19th and 20th with the airport recording the nations high temperature of 84° on the 20th. This is the fourth time in 2016 that the Tucson airport has recorded the nations high temperature. The previous three occurred in January.
A Pacific weather system then brought scattered showers and isolated thunderstorms to the area late on the 20th into the 21st followed by cooler daytime temperatures in the upper 60s on the 22nd. High temperatures warmed back into the upper 70s for most of the Thanksgiving holiday four day period.
With four days left in the month, the average temperature at the airport stood at 66.3° and was threatening the warmest November on record. However a complex Pacific weather system brought much cooler temperatures to end of the month. Valley rain and mountain snow also accompanied this system with the first measurable snowfall of the season occurring on the surrounding mountains. Cameras showed that between two and four inches of snow fell in Summerhaven. High temperatures during the last four days of the month were in the upper 50s to lower 60s, while the first freeze of the 2016-17 season occurred on the 30th when the airport bottomed out at a chilly 29°.
Thanks to the chilly end of the month the average temperature for November ended up at 64.0° which ranks as the 6th warmest November on record, tied with 1894. Temperature extremes for the month ranged from a high of 89° on the 15th to a low of 29° on the 30th.
November 2016 daily high temperature departure from normal November 2016 daily low temperature departure from normal
The images above (click on them for larger view) show daily departure from (1981-2010) normals. Below normal is blueand above normal is red.
Rainfall amounts across the metro area, using several sources like rainlog.org, the Pima County Regional Flood Control District gages and CoCoRaHS, mostly ranging from 0.10″ to 0.60″ with localized spots near 1.00″. At the International airport, which is the official recording location in Tucson, 0.50″ was recorded which ranks as the 58th wettest November on record.
November 2016 stats
Month
Normal
Departure
Average high temperature
77.3°
73.5°
+ 3.8°
Average low temperature
50.7°
46.1°
+ 4.6°
Average temperature
64.0°
59.8°
+ 4.2°
Rainfall
0.50″
0.57″
– 0.07″

Fall 2016 climate report for Tucson
Headlines
WARMEST on record
55th driest on record
12th straight Fall with above normal temperatures
..
Tucson experienced the WARMEST Fall on record with an average temperature of 74.1°. The previous warmest Fall was in 1999 with an average temperature of 74.0°. This is also the 12th straight Fall that the average temperature has been above normal. Temperature extremes ranged from a high of 104° on September 5th to a low of 29° on November 30th.
Fall 2016 daily high temperature departure from normal Fall 2016 daily low temperature departure from normal
The images above (click on them for larger view) show daily departure from (1981-2010) normals. Below normal is blue and above normal is red.
After three consecutive Fall seasons that were wetter than normal, Fall 2016 was drier than normal with 2.20″ being recorded at the International airport, which is the official recording location in Tucson. This ranks as the 55th driest Fall on record. Rainfall amounts across the metro area, using several sources like rainlog.org, the Pima County Regional Flood Control District gages and CoCoRaHS, mostly ranged from 1.50″ to 3″ with localized spots near 4″.
Fall 2016 stats
Season
Normal
Departure
Average high temperature
87.6°
84.2°
+ 3.4°
Average low temperature
60.6°
57.3°
+ 3.3°
Average temperature
74.1°
70.8°
+ 3.3°
Rainfall
2.20″
2.75″
– 0.55″

2016
The average yearly temperature of 73.6° ranks as the 2nd warmest on record to date, three-tenths of a degree behind behind 2014 (73.9°). The 2016 rainfall total of 10.73″ at the International airport, which is the official recording location in Tucson, ranks as the 47th wettest January through November period on record.
2016 stats thru November
Year
Normal
Departure
Average high temperature
87.4°
84.9°
+ 2.5°
Average low temperature
59.7
57.2°
+ 2.5°
Average temperature
73.6°
71.1°
+ 2.5°
Number of 100°+ highs
61
62
+ 1
Rainfall
10.73″
10.66″
+ 0.07″
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s