Monthly outlook for Waiau, HI: average high 82.8°, average low 77°. That is 0.5° below the climate normal for August. Precipitation is expected on 6 days (about 1.9 inches), against a normal of 4 days and 0.5 inches. The warmest day looks like 17 August (84.7°), the coolest 12 August (75.7°).
82.8°/77°
Average high / low
−0.5°
Below normal
6 / 4
Wet days / normal
1.9 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 August – 17 August
83°
83.6°
-0.4°
18 August – 27 August
82.5°
83.7°
-0.7°
28 August – 6 September
at normal
83.9°
—
August records over 66 years
91.8°8 August 2019All-time high
67.8°31 August 2021All-time low
Climate normals and records are computed from the nearest reference point — Waikele (3 mi).
Sun, 0983° / 77°0
83 °
Waiau, Sunday, 9 August
Partly cloudy. High 83°, low 77°.
Pressure30.00 inHg
Wind14.7 mph E
Humidity68%
Visibility6.2 mi
Dew point70°
Mon, 1084° / 78°0
84 °
Waiau, Monday, 10 August
Mostly clear. High 84°, low 78°.
Pressure29.97 inHg
Wind13.5 mph NE
Humidity64%
Visibility6.2 mi
Dew point69°
Tue, 1183° / 76°0
83 °
Waiau, Tuesday, 11 August
Overcast. High 83°, low 76°.
Pressure29.94 inHg
Wind13.7 mph E
Humidity58%
Visibility6.2 mi
Dew point66°
Wed, 1283° / 76°0
83 °
Waiau, Wednesday, 12 August
Partly cloudy. High 83°, low 76°.
Pressure29.94 inHg
Wind14.8 mph E
Humidity59%
Visibility6.2 mi
Dew point66°
Thu, 1383° / 77°0
83 °
Waiau, Thursday, 13 August
Overcast. High 83°, low 77°.
Pressure29.94 inHg
Wind19.1 mph NE
Humidity63%
Visibility—
Dew point68°
Fri, 1483° / 77°0
83 °
Waiau, Friday, 14 August
Mostly clear. High 83°, low 77°.
Pressure29.94 inHg
Wind20.9 mph NE
Humidity65%
Visibility—
Dew point68°
Sat, 1582° / 77°0.08
82 °
Waiau, Saturday, 15 August
Light rain. High 82°, low 77°.
Pressure29.94 inHg
Wind21.5 mph NE
Humidity73%
Visibility—
Dew point72°
Sun, 1678° / 77°1.48
78 °
Waiau, Sunday, 16 August
Heavy rain. High 78°, low 77°.
Pressure29.41 inHg
Wind33.7 mph N
Humidity91%
Visibility—
Dew point75°
Mon, 1785° / 77°0.08
85 °
Waiau, Monday, 17 August
Light rain. High 85°, low 77°.
Pressure30.03 inHg
Wind13.7 mph S
Humidity74%
Visibility—
Dew point73°
Tue, 1882° / 77°0.03
82 °
Waiau, Tuesday, 18 August
Light rain. High 82°, low 77°.
Pressure30.06 inHg
Wind16.8 mph NE
Humidity68%
Visibility—
Dew point68°
Wed, 1980° / 76°0.05
80 °
Waiau, Wednesday, 19 August
Light rain. High 80°, low 76°.
Pressure30.03 inHg
Wind19.9 mph NE
Humidity76%
Visibility—
Dew point71°
Thu, 2082° / 76°0
82 °
Waiau, Thursday, 20 August
Light rain. High 82°, low 76°.
Pressure30.00 inHg
Wind12.2 mph E
Humidity61%
Visibility—
Dew point66°
Fri, 2183° / 77°0.07
83 °
Waiau, Friday, 21 August
Light rain. High 83°, low 77°.
Pressure30.00 inHg
Wind11.3 mph E
Humidity74%
Visibility—
Dew point73°
Sat, 2284° / 78°0.04
84 °
Waiau, Saturday, 22 August
Light rain. High 84°, low 78°.
Pressure30.03 inHg
Wind12.3 mph NE
Humidity73%
Visibility—
Dew point73°
Sun, 2384° / 78°0
84 °
Waiau, Sunday, 23 August
Light rain. High 84°, low 78°.
Pressure30.00 inHg
Wind17.5 mph E
Humidity65%
Visibility—
Dew point69°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2484° / 75°0.07
84 °
Waiau, Monday, 24 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.07 in
Chance of precipitation30%
Record high90° (2019)
Record low72° (2022)
Tue, 2584° / 75°0.03
84 °
Waiau, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation17%
Record high90° (2025)
Record low71° (2025)
Wed, 2684° / 75°0.03
84 °
Waiau, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation27%
Record high90° (2019)
Record low72° (2025)
Thu, 2784° / 75°0.03
84 °
Waiau, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation22%
Record high90° (2019)
Record low71° (2024)
Fri, 2884° / 75°0.03
84 °
Waiau, Friday, 28 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation28%
Record high91° (2019)
Record low71° (2024)
Sat, 2984° / 75°0.02
84 °
Waiau, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.02 in
Chance of precipitation20%
Record high91° (2019)
Record low71° (2025)
Sun, 3084° / 75°0.03
84 °
Waiau, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation28%
Record high90° (2023)
Record low70° (2025)
Mon, 3184° / 75°0.04
84 °
Waiau, Monday, 31 August
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.04 in
Chance of precipitation33%
Record high90° (2019)
Record low68° (2021)
Tue, 0184° / 75°0.04
84 °
Waiau, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.04 in
Chance of precipitation38%
Record high90° (2019)
Record low69° (2021)
Wed, 0284° / 75°0.03
84 °
Waiau, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation32%
Record high90° (2020)
Record low69° (2025)
Thu, 0384° / 75°0.04
84 °
Waiau, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.04 in
Chance of precipitation38%
Record high90° (2019)
Record low70° (2023)
Fri, 0484° / 75°0.04
84 °
Waiau, Friday, 4 September
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.04 in
Chance of precipitation33%
Record high91° (2025)
Record low68° (2023)
Sat, 0584° / 75°0.03
84 °
Waiau, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.03 in
Chance of precipitation35%
Record high91° (2023)
Record low69° (2023)
Sun, 0684° / 75°0.02
84 °
Waiau, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high84°
Average low75°
Average precipitation0.02 in
Chance of precipitation13%
Record high89° (2024)
Record low68° (2023)
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 Waiau, HI 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 Waiau, HI 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.