Monthly outlook for Ortonville, IA: average high 90.4°, average low 68.6°. That is 4.9° above the climate normal for August. Precipitation is expected on 5 days (about 1.4 inches), against a normal of 5 days and 2.0 inches. The warmest day looks like 22 August (113.1°), the coolest 15 August (59.7°).
90.4°/68.6°
Average high / low
+4.9°
Above normal
5 / 5
Wet days / normal
1.4 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
84.9°
81.7°
+1.8°
19 August – 28 August
99.8°
81.8°
+10°
29 August – 7 September
at normal
80°
—
August records over 66 years
101.1°16 August 1983All-time high
43.9°28 August 1986All-time low
Climate normals and records are computed from the nearest reference point — Urbandale (9 mi).
Mon, 1087° / 71°0.04
87 °
Ortonville, Monday, 10 August
Light rain. High 87°, low 71°.
Pressure29.85 inHg
Wind15.4 mph SE
Humidity57%
Visibility6.2 mi
Dew point71°
Tue, 1198° / 70°0.01
98 °
Ortonville, Tuesday, 11 August
Light rain. High 98°, low 70°.
Pressure29.74 inHg
Wind10.4 mph SW
Humidity37%
Visibility6.2 mi
Dew point63°
Wed, 1291° / 72°0.03
91 °
Ortonville, Wednesday, 12 August
Light rain. High 91°, low 72°.
Pressure29.85 inHg
Wind4.7 mph NE
Humidity60%
Visibility6.2 mi
Dew point67°
Thu, 1381° / 62°0.39
81 °
Ortonville, Thursday, 13 August
Rain. High 81°, low 62°.
Pressure29.94 inHg
Wind16.2 mph NE
Humidity41%
Visibility—
Dew point53°
Fri, 1466° / 62°0.71
66 °
Ortonville, Friday, 14 August
Heavy rain. High 66°, low 62°.
Pressure30.12 inHg
Wind13.1 mph E
Humidity94%
Visibility—
Dew point62°
Sat, 1571° / 60°0.04
71 °
Ortonville, Saturday, 15 August
Light rain. High 71°, low 60°.
Pressure30.15 inHg
Wind10.4 mph SE
Humidity85%
Visibility—
Dew point63°
Sun, 1683° / 67°0
83 °
Ortonville, Sunday, 16 August
Overcast. High 83°, low 67°.
Pressure30.12 inHg
Wind9.2 mph N
Humidity59%
Visibility—
Dew point63°
Mon, 1787° / 66°0
87 °
Ortonville, Monday, 17 August
Overcast. High 87°, low 66°.
Pressure30.06 inHg
Wind8.9 mph S
Humidity53%
Visibility—
Dew point63°
Tue, 1891° / 66°0
91 °
Ortonville, Tuesday, 18 August
Overcast. High 91°, low 66°.
Pressure29.88 inHg
Wind15.1 mph S
Humidity55%
Visibility—
Dew point67°
Wed, 19100° / 70°0
100 °
Ortonville, Wednesday, 19 August
Overcast. High 100°, low 70°.
Pressure29.77 inHg
Wind8.3 mph E
Humidity29%
Visibility—
Dew point58°
Thu, 20100° / 73°0
100 °
Ortonville, Thursday, 20 August
Overcast. High 100°, low 73°.
Pressure29.77 inHg
Wind14.3 mph NE
Humidity39%
Visibility—
Dew point65°
Fri, 2192° / 70°0.04
92 °
Ortonville, Friday, 21 August
Light rain. High 92°, low 70°.
Pressure29.94 inHg
Wind14.6 mph E
Humidity39%
Visibility—
Dew point57°
Sat, 22113° / 72°0
113 °
Ortonville, Saturday, 22 August
Partly cloudy. High 113°, low 72°.
Pressure29.74 inHg
Wind17.6 mph SW
Humidity25%
Visibility—
Dew point55°
Sun, 2398° / 74°0.1
98 °
Ortonville, Sunday, 23 August
Light rain. High 98°, low 74°.
Pressure29.83 inHg
Wind17.7 mph NE
Humidity42%
Visibility—
Dew point64°
Mon, 2496° / 69°0.03
96 °
Ortonville, Monday, 24 August
Light rain. High 96°, low 69°.
Pressure29.91 inHg
Wind8.8 mph S
Humidity44%
Visibility—
Dew point64°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2582° / 65°0.14
82 °
Ortonville, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0.14 in
Chance of precipitation35%
Record high97° (2003)
Record low52° (2015)
Wed, 2682° / 66°0.19
82 °
Ortonville, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high82°
Average low66°
Average precipitation0.19 in
Chance of precipitation37%
Record high95° (2013)
Record low50° (2015)
Thu, 2782° / 66°0.16
82 °
Ortonville, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high82°
Average low66°
Average precipitation0.16 in
Chance of precipitation35%
Record high96° (2013)
Record low52° (1971)
Fri, 2882° / 64°0.18
82 °
Ortonville, Friday, 28 August
Climate normal for this date — 60-year average.
Average high82°
Average low64°
Average precipitation0.18 in
Chance of precipitation32%
Record high96° (1984)
Record low44° (1986)
Sat, 2982° / 64°0.11
82 °
Ortonville, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high82°
Average low64°
Average precipitation0.11 in
Chance of precipitation23%
Record high94° (1984)
Record low49° (1988)
Sun, 3081° / 64°0.1
81 °
Ortonville, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high81°
Average low64°
Average precipitation0.1 in
Chance of precipitation27%
Record high98° (2013)
Record low49° (2009)
Mon, 3180° / 63°0.09
80 °
Ortonville, Monday, 31 August
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.09 in
Chance of precipitation25%
Record high93° (2000)
Record low48° (2009)
Tue, 0180° / 63°0.09
80 °
Ortonville, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.09 in
Chance of precipitation23%
Record high94° (1984)
Record low46° (1967)
Wed, 0280° / 64°0.11
80 °
Ortonville, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high80°
Average low64°
Average precipitation0.11 in
Chance of precipitation33%
Record high94° (2000)
Record low52° (1974)
Thu, 0380° / 63°0.09
80 °
Ortonville, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.09 in
Chance of precipitation23%
Record high96° (2023)
Record low42° (1974)
Fri, 0479° / 62°0.09
79 °
Ortonville, Friday, 4 September
Climate normal for this date — 60-year average.
Average high79°
Average low62°
Average precipitation0.09 in
Chance of precipitation28%
Record high96° (2023)
Record low44° (1974)
Sat, 0580° / 62°0.09
80 °
Ortonville, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high80°
Average low62°
Average precipitation0.09 in
Chance of precipitation20%
Record high94° (2023)
Record low44° (1962)
Sun, 0679° / 62°0.09
79 °
Ortonville, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high79°
Average low62°
Average precipitation0.09 in
Chance of precipitation23%
Record high93° (2020)
Record low45° (1988)
Mon, 0779° / 62°0.13
79 °
Ortonville, Monday, 7 September
Climate normal for this date — 60-year average.
Average high79°
Average low62°
Average precipitation0.13 in
Chance of precipitation28%
Record high93° (1971)
Record low43° (2025)
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 Ortonville, IA 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 Ortonville, IA 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.