Monthly outlook for Rainbow Valley, AZ: average high 103.5°, average low 84.8°. That is 0.1° above the climate normal for August. Precipitation is expected on 6 days (about 1.8 inches), against a normal of 2 days and 0.8 inches. The warmest day looks like 9 August (113.4°), the coolest 20 August (74°).
103.5°/84.8°
Average high / low
+0.1°
Above normal
6 / 2
Wet days / normal
1.8 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
104.5°
103.5°
+0.5°
19 August – 28 August
102°
103.1°
-0.6°
29 August – 7 September
at normal
102.5°
—
August records over 66 years
117.5°7 August 2025All-time high
64.4°23 August 1968All-time low
Climate normals and records are computed from the nearest reference point — Avondale (11 mi).
Mon, 10110° / 83°0.08
110 °
Rainbow Valley, Monday, 10 August
Light rain. High 110°, low 83°.
Pressure29.85 inHg
Wind9.8 mph W
Humidity26%
Visibility6.2 mi
Dew point59°
Tue, 11104° / 83°0
104 °
Rainbow Valley, Tuesday, 11 August
Clear. High 104°, low 83°.
Pressure29.88 inHg
Wind8.3 mph W
Humidity30%
Visibility6.2 mi
Dew point62°
Wed, 12100° / 84°0.17
100 °
Rainbow Valley, Wednesday, 12 August
Light rain. High 100°, low 84°.
Pressure29.83 inHg
Wind1.1 mph SW
Humidity31%
Visibility6.2 mi
Dew point60°
Thu, 13100° / 82°0.16
100 °
Rainbow Valley, Thursday, 13 August
Rain. High 100°, low 82°.
Pressure29.83 inHg
Wind13.7 mph SW
Humidity32%
Visibility—
Dew point57°
Fri, 14100° / 85°0
100 °
Rainbow Valley, Friday, 14 August
Overcast. High 100°, low 85°.
Pressure29.88 inHg
Wind7.7 mph SW
Humidity26%
Visibility—
Dew point53°
Sat, 15103° / 87°0
103 °
Rainbow Valley, Saturday, 15 August
Overcast. High 103°, low 87°.
Pressure29.91 inHg
Wind11.1 mph W
Humidity20%
Visibility—
Dew point49°
Sun, 16102° / 85°0
102 °
Rainbow Valley, Sunday, 16 August
Clear. High 102°, low 85°.
Pressure30.00 inHg
Wind8.2 mph W
Humidity23%
Visibility—
Dew point51°
Mon, 17105° / 88°0
105 °
Rainbow Valley, Monday, 17 August
Overcast. High 105°, low 88°.
Pressure29.91 inHg
Wind8.4 mph W
Humidity24%
Visibility—
Dew point54°
Tue, 18105° / 88°0.04
105 °
Rainbow Valley, Tuesday, 18 August
Light rain. High 105°, low 88°.
Pressure29.83 inHg
Wind11.7 mph SE
Humidity25%
Visibility—
Dew point56°
Wed, 19103° / 80°0.73
103 °
Rainbow Valley, Wednesday, 19 August
Rain. High 103°, low 80°.
Pressure29.85 inHg
Wind23.2 mph E
Humidity31%
Visibility—
Dew point61°
Thu, 20101° / 74°0.59
101 °
Rainbow Valley, Thursday, 20 August
Rain. High 101°, low 74°.
Pressure29.91 inHg
Wind27.4 mph SE
Humidity41%
Visibility—
Dew point65°
Fri, 2199° / 79°0
99 °
Rainbow Valley, Friday, 21 August
Partly cloudy. High 99°, low 79°.
Pressure29.88 inHg
Wind6.9 mph W
Humidity38%
Visibility—
Dew point61°
Sat, 22104° / 88°0
104 °
Rainbow Valley, Saturday, 22 August
Clear. High 104°, low 88°.
Pressure29.85 inHg
Wind7.4 mph SW
Humidity25%
Visibility—
Dew point55°
Sun, 23105° / 88°0
105 °
Rainbow Valley, Sunday, 23 August
Mostly clear. High 105°, low 88°.
Pressure29.83 inHg
Wind9.6 mph W
Humidity18%
Visibility—
Dew point48°
Mon, 24100° / 89°0
100 °
Rainbow Valley, Monday, 24 August
Partly cloudy. High 100°, low 89°.
Pressure29.83 inHg
Wind5.6 mph SW
Humidity24%
Visibility—
Dew point54°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 25103° / 80°0.04
103 °
Rainbow Valley, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high103°
Average low80°
Average precipitation0.04 in
Chance of precipitation15%
Record high113° (2011)
Record low67° (1990)
Wed, 26103° / 81°0.03
103 °
Rainbow Valley, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high103°
Average low81°
Average precipitation0.03 in
Chance of precipitation13%
Record high113° (2001)
Record low70° (1960)
Thu, 27103° / 80°0.04
103 °
Rainbow Valley, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high103°
Average low80°
Average precipitation0.04 in
Chance of precipitation15%
Record high112° (1981)
Record low70° (1992)
Fri, 28104° / 81°0.02
104 °
Rainbow Valley, Friday, 28 August
Climate normal for this date — 60-year average.
Average high104°
Average low81°
Average precipitation0.02 in
Chance of precipitation7%
Record high114° (1998)
Record low69° (1992)
Sat, 29104° / 81°0.03
104 °
Rainbow Valley, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high104°
Average low81°
Average precipitation0.03 in
Chance of precipitation12%
Record high114° (2023)
Record low71° (1964)
Sun, 30103° / 80°0.03
103 °
Rainbow Valley, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high103°
Average low80°
Average precipitation0.03 in
Chance of precipitation15%
Record high112° (2011)
Record low69° (1992)
Mon, 31103° / 81°0.02
103 °
Rainbow Valley, Monday, 31 August
Climate normal for this date — 60-year average.
Average high103°
Average low81°
Average precipitation0.02 in
Chance of precipitation12%
Record high112° (2011)
Record low70° (1962)
Tue, 01102° / 80°0.03
102 °
Rainbow Valley, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high102°
Average low80°
Average precipitation0.03 in
Chance of precipitation13%
Record high112° (2011)
Record low64° (1992)
Wed, 02102° / 80°0.06
102 °
Rainbow Valley, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high102°
Average low80°
Average precipitation0.06 in
Chance of precipitation13%
Record high111° (1982)
Record low65° (1992)
Thu, 03103° / 80°0.01
103 °
Rainbow Valley, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high103°
Average low80°
Average precipitation0.01 in
Chance of precipitation5%
Record high110° (2010)
Record low66° (1999)
Fri, 04102° / 79°0.06
102 °
Rainbow Valley, Friday, 4 September
Climate normal for this date — 60-year average.
Average high102°
Average low79°
Average precipitation0.06 in
Chance of precipitation10%
Record high112° (2020)
Record low67° (1961)
Sat, 05102° / 79°0.07
102 °
Rainbow Valley, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high102°
Average low79°
Average precipitation0.07 in
Chance of precipitation20%
Record high114° (2020)
Record low64° (1992)
Sun, 06102° / 79°0.03
102 °
Rainbow Valley, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high102°
Average low79°
Average precipitation0.03 in
Chance of precipitation15%
Record high112° (2020)
Record low62° (1970)
Mon, 07101° / 79°0.02
101 °
Rainbow Valley, Monday, 7 September
Climate normal for this date — 60-year average.
Average high101°
Average low79°
Average precipitation0.02 in
Chance of precipitation13%
Record high111° (1979)
Record low65° (1965)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Rainbow Valley, AZ are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Rainbow Valley, AZ since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.