| July 2009
climate report for Tucson |
| |
| July
2009 headlines |
Decade
of 2000s headlines |
| 3rd warmest
July on record |
Warmest
July decade on record |
| Summer
rains fizzle at the end of month |
3rd wettest
July decade on record |
| 4th
warmest January-July period on record |
|
| |
| Very
warm temperatures, fickle monsoonal flow and severe storms highlighted
the weather during July 2009. |
| |
| The
month started off like June ended, with below normal daytime temperatures
(readings in the mid to upper 90s through the 4th) and monsoonal flow
in place. Severe thunderstorms hit the area on the 2nd with flash
flooding occuring on the far southeast side on the 4th. Daytime temperatures
finally stayed above 100° starting on the 5th with scattered thunderstorms
impacting the area through mid-July. Severe thunderstorms once again
hit the area on the 7th and 10th along with locally heavy rain which
produced localized flash flooding. |
| |
| The
summer rains fizzled out during the second half of the month as high
pressure aloft, normally near the four corners area during the latter
part of July, was displaced further south which kept deep moisture
to our south. Daytime high temperatures responded to the stronger
high overhead with daytime readings above 100 degrees. The exception
was on the 23rd through the 25th where a bit more moisture moved in,
which led to scattered showers and thunderstorms and high temperatures
in the upper 90s. The month ended up hot as deep monsoonal moisture
was scoured out of the area. |
| |
| July
2009 goes into the record books as the 3rd warmest July on
record with an average monthly temperature of 90.1 degrees, which
is 3.6 degrees above normal. This also ranks as the 4th
warmest calender month on record. The average monthly low temperatures
of 77.6 degrees goes into the record books as the warmest on
record for July and also the warmest for a calendar month. |
| |
| Warmest
average |
| July
temperatures |
| Rank |
Avg |
Year |
| 1 |
90.6° |
2005 |
| 2 |
90.4° |
1994 |
| 3 |
90.1° |
2009 |
| 4 |
89.9° |
1989 |
| 5 |
89.7° |
1942 |
|
|
| Warmest
calendar |
| months |
| Rank |
Avg |
Year |
| 1 |
90.6° |
Jul
2005 |
| 2 |
90.4° |
Jul
1994 |
| 3 |
90.2° |
Aug
1994 |
| 4 |
90.1° |
Jul
2009 |
| 5 |
89.9° |
Jul
1989 |
|
|
| Warmest
average |
| July
low temperature |
| Rank |
Avg |
Year |
| 1 |
77.6° |
2009 |
| 2T |
76.9° |
2006 |
| 76.9° |
2005 |
| 4 |
76.3° |
1996 |
| 5 |
76.0° |
2007 |
|
|
| Warmest
average |
| low
temperature calendar months |
| Rank |
Avg |
Year |
| 1 |
77.6° |
Jul
2009 |
| 2T |
76.9° |
Jul
2006 |
| 76.9° |
Jul
2005 |
| 4 |
76.5° |
Aug
1994 |
| 5 |
76.3° |
Jul
1996 |
|
|
| |
|
Starting on the 10th and continuing until the end of the month, a
streak of 22 consecutive days, each daily low temperature was 75 degrees
or warmer. This easily eclipsed the old record of 18 consecutive days
set in 2006 and in 2003. The table below lists the top 5 longest streaks. |
| |
| Longest
streaks with low temperature of 75 degrees or warmer |
| Rank |
#
of days |
Year/Dates |
Average
low temperature |
| 1) |
22 |
2009
(7/10-31) |
78.9° |
| 2T) |
18 |
2006
(7/9-26) |
80.6° |
| 18 |
2003
(6/28-7/15) |
77.8° |
| 4T) |
17 |
2007
(7/2-18) |
79.8° |
| 17 |
2005
(7/13-29) |
79.1° |
|
| |
|
Temperature extremes for the month ranged from a high of 109 degrees
on the 19th to a low of 68 degrees on the 4th. Two daily record temperature
were set during July. The high of 109 degrees on the 19th broke the
previous record of 108 degrees which occurred in 1989, 1978 and 1920.
The low temperature of 80 degrees on the 30th tied that dates record
previously set in 1993, 1907 and 1906. |
| |
|
As is normally
the case during July, rainfall totals were highly variable across
the area as they ranged from around one inch to four and a half
inches, with the highest amounts occurring near the Tucson mountains
and up in Oro Valley. Officially, the International airport recorded
1.78" of rain, which is about three-tenths of an inch below
normal. This is the first July since 2005 that the airport recorded
below normal rainfall.
|
| |
| July
2009 stats |
Month
|
Normal
|
Departure
|
| Average
high temperature |
102.5°
|
99.6°
|
+
2.9°
|
| Average
low temperature |
77.6°
|
73.4°
|
+
4.2°
|
| Average
temperature |
90.1°
|
86.5°
|
+
3.6°
|
| Number
of 100+ degree highs |
24
|
17
|
+
7
|
| Rainfall |
1.78"
|
2.07"
|
-
0.29"
|
|
| |
| 2009
stats thru July |
Year
|
Normal
|
Departure
|
| Average
high temperature |
85.3°
|
82.6°
|
+
2.7°
|
| Average
low temperature |
56.8°
|
53.8°
|
+
3.0°
|
| Average
temperature |
71.0°
|
68.2°
|
+
2.8°
|
| Number
of 100+ degree highs |
42
|
36
|
+
6
|
| Rainfall |
4.12"
|
5.51"
|
-
1.39"
|
| 2008-09
Water Year rainfall (Oct-July) |
5.44"
|
8.42"
|
-
2.98"
|
| |
|
|
|
|
| The
first half of 2009 goes into the records books as the 4th warmest
on record with an average temperature of 71.0 degrees. The warmest
January to July period occurred in 1989 when the average temperature
was 71.5 degrees. The 2008-2009 water year rainfall total at the airport
is nearly three inches below normal. This ranks as the 24st driest
water year to date. |
| |
July decade in review: the 2000s
|
|
The month of
July during the decade of the 2000s will go into the record books
as the warmest and 3rd wettest decade on record (dating
back to the mid-1890s). The decadal average temperature of 88.0
degrees is seven-tenths of degree warmer than the 1990s. Thanks
to the 5.40" in 2006 and 5.22" in 2007, the 5th and 6th
wettest July's on record respectively at the airport,
the average decadal precipitation of 2.51" was the wettest
July decade since the 1950s.
|
| Decadal
average temperatures |
| 2000s |
1990s |
1980s |
1970s |
1960s |
1950s |
1940s |
1930s |
1920s |
1910s |
1900s |
| 88.0° |
87.3° |
86.8° |
86.0° |
85.7° |
86.2° |
87.1° |
86.6° |
86.2° |
84.4° |
85.6° |
| Decadal
average precipitation |
| 2000s |
1990s |
1980s |
1970s |
1960s |
1950s |
1940s |
1930s |
1920s |
1910s |
1900s |
| 2.51" |
1.81" |
2.34" |
2.15" |
2.13" |
3.16" |
1.69" |
1.46" |
1.93" |
2.84" |
2.29" |
|
| |
|
2005 (90.6°),
2009 (90.1°) and 2003 (89.2°) are ranked as the 1st,
3rd and 6th warmest July's on record respectively. As mentioned
above, 2006 (5.40") and 2007 (5.22") ranks as the 5th
and 6th wettest July's on record respectively.
|
| Year-by-year
statistical recap for Tucson International airport |
| Year |
Avg.
high |
Avg.
Low |
Avg.
Temp |
Precip. |
| 2000 |
101.0° |
75.3° |
88.2° |
1.59" |
| 2001 |
97.4° |
74.9° |
86.2° |
1.09" |
| 2002 |
99.1° |
74.5° |
86.8° |
2.47" |
| 2003 |
102.5° |
75.9° |
89.2° |
2.50" |
| 2004 |
99.9° |
73.7° |
86.8° |
0.86" |
| 2005 |
104.2° |
76.9° |
90.6° |
0.72" |
| 2006 |
99.7° |
76.9° |
88.3° |
5.40" |
| 2007 |
99.8° |
76.0° |
87.9° |
5.22" |
| 2008 |
96.9° |
74.3° |
85.6° |
3.42" |
| 2009 |
102.5° |
77.6° |
90.1° |
1.78" |
| 2000s
avg. |
100.3° |
75.6° |
88.0° |
2.51" |
| 1971-2000
normal |
99.6° |
73.4° |
86.5° |
2.07" |
| Click
on a year for full climate report previously posted. |
|
| |
|
The first two
graphs below shows the daily departure from normal, or periods of
warm/cold, for each July day from 2000 through 2009. The third graph
is the departure from normal for the monthly average temperatures.
The fourth graph is the departure from normal for the monthly rainfall.
(all years compared against 1971-2000 normals except 2000/2001 which
were compared to 1961-1990 normals).
|
|
[Daily
highs] [Daily
lows] [July
average temperatures] [July
precipitation] |
| Move
your mouse over the locations to change graphics. Click link for larger
view. |
 |
| |
|
Temperature
extremes for the decade ranged from 111 degrees on July 17,
2005 and July 2, 2001 to 62 degrees on July 2, 2004. Twenty-five
record temperatures were set/tied this past decade (listing below
is in chronological order).
|
|
|
|
|
|
| Record
type |
Date |
Record |
Previous |
Year(s) |
| High
Minimum |
July
28, 2000 |
83° |
82° |
1979 |
| High |
July
2, 2001 |
111°
(tied) |
111° |
1994/1907 |
| Low |
July
14, 2002 |
65°
(tied) |
65° |
1962 |
| Low
Maximum |
July
27, 2002 |
82° |
85° |
1975 |
| High |
July
16, 2003 |
110° |
108° |
1998/1997/1925 |
| High
Minimum |
July
21, 2004 |
82°
(tied) |
82° |
1932 |
| High
Minimum |
July
22, 2004 |
84° |
81° |
1996 |
| High |
July
6, 2005 |
109°
(tied) |
109° |
1989 |
| High |
July
12, 2005 |
110° |
109° |
1994/1985/1925 |
| High
Minimum |
July
13, 2005 |
86° |
85° |
1940 |
| High
Minimum |
July
17, 2005 |
85° |
82° |
1997 |
| High |
July
17, 2005 |
111° |
109° |
1992 |
| High
Minimum |
July
21, 2005 |
82°
(tied) |
82° |
2004/1932 |
| High |
July
21, 2005 |
108° |
107° |
1931 |
| High |
July
21, 2006 |
110° |
108° |
2005 |
| High
Minimum |
July
22, 2006 |
89° |
84° |
2004 |
| High |
July
22, 2006 |
108° |
107° |
1994/1987 |
| High
Minimum |
July
23, 2006 |
85° |
82° |
1943/1932 |
| Low |
July
31, 2006 |
66°
(tied) |
66° |
1955/1921/1905 |
| High
Minimum |
July
5, 2007 |
87° |
83° |
1953 |
| High
Minimum |
July
6, 2007 |
87°
(tied) |
87° |
1925 |
| Low
Maximum |
July
10, 2008 |
86°
(tied) |
86° |
1930 |
| Low
Maximum |
July
11, 2008 |
89°
(tied) |
89° |
1992/1949/1919 |
| High |
July
19, 2009 |
109° |
108° |
1989/1978/1920 |
| High
Minimum |
July
30, 2009 |
80°
(tied) |
80° |
1993/1907/1906 |
|
| |
| Two
rainfall record were set during the 2000s |
| Date |
Record |
Previous
/ Year (s) |
| July 11,
2008 |
1.73" |
0.90"
/ 1919 |
| July 31,
2006 |
1.90" |
1.43"
/ 1955 & 1921 |
|
| |
| Looking
ahead into August |
| The
Climate Prediction Center
forecasts, due to strengthening of El
Niño, enhanced probabilities of above
normal temperatures and enhanced probabilities for below normal
precipitation. |
| |
|
| Normal
high temperature |
97.4° |
| Normal
low temperature |
72.4° |
| Normal
monthly temperature |
84.9° |
| Record
high temperature |
112°
on August 1, 1993 |
| Record
low temperature |
55°
on August 20, 1917 |
| Warmest
August (avg) |
90.3°
in 1994 |
| Coldest
August (avg) |
80.8°
in 1923 |
| Normal
rainfall |
2.30" |
| Wettest
August day |
2.88"
on August 1, 1935 |
| Wettest
August |
7.93"
in 1955 |
| Driest
August |
0.08"
in 1924 |
| |
|
|
The number
of daylight hours will increase from 13 hours 42 minutes on
the 1st to 12 hours 51 minutes on the 31st, a loss of 51 minutes.
|
|
| |
Glueck
|
www.weather.gov 
