Monthly outlook for Castalia, IA: average high 58.6°, average low 45.6°. That is 3.9° above the climate normal for October. Precipitation is expected on 1 day (about 0.9 inches), against a normal of 4 days and 1.3 inches. The warmest day looks like 23 October (72°), the coolest 7 November (33.8°).
58.6°/45.6°
Average high / low
+3.9°
Above normal
1 / 4
Wet days / normal
0.9 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
23 October – 1 November
62.7°
53.1°
+5.3°
2 November – 11 November
51.8°
47.6°
+2.3°
12 November – 21 November
at normal
42.9°
—
October records over 66 years
86.4°1 October 1976All-time high
19.9°30 October 1988All-time low
Climate normals and records are computed from the nearest reference point — West Union (13 mi).
Sat, 2471° / 52°0.01
71 °
Castalia, Saturday, 24 October
Light rain. High 71°, low 52°.
Pressure30.24 inHg
Wind12.7 mph S
Humidity62%
Visibility6.2 mi
Dew point52°
Sun, 2565° / 55°0
65 °
Castalia, Sunday, 25 October
Overcast. High 65°, low 55°.
Pressure30.36 inHg
Wind4.4 mph NE
Humidity75%
Visibility6.2 mi
Dew point55°
Mon, 2659° / 51°0
59 °
Castalia, Monday, 26 October
Overcast. High 59°, low 51°.
Pressure30.42 inHg
Wind9.5 mph E
Humidity59%
Visibility6.2 mi
Dew point42°
Tue, 2764° / 47°0
64 °
Castalia, Tuesday, 27 October
Overcast. High 64°, low 47°.
Pressure30.24 inHg
Wind12.2 mph SE
Humidity70%
Visibility—
Dew point48°
Wed, 2865° / 52°0.01
65 °
Castalia, Wednesday, 28 October
Light rain. High 65°, low 52°.
Pressure29.97 inHg
Wind17.5 mph S
Humidity60%
Visibility—
Dew point49°
Thu, 2960° / 48°0.02
60 °
Castalia, Thursday, 29 October
Light rain. High 60°, low 48°.
Pressure30.15 inHg
Wind14.6 mph SW
Humidity60%
Visibility—
Dew point42°
Fri, 3058° / 41°0
58 °
Castalia, Friday, 30 October
Partly cloudy. High 58°, low 41°.
Pressure30.15 inHg
Wind10.2 mph E
Humidity61%
Visibility—
Dew point41°
Sat, 3156° / 51°0.78
56 °
Castalia, Saturday, 31 October
Rain. High 56°, low 51°.
Pressure29.80 inHg
Wind18.3 mph S
Humidity95%
Visibility—
Dew point53°
Sun, 0157° / 46°0.02
57 °
Castalia, Sunday, 1 November
Light rain. High 57°, low 46°.
Pressure30.03 inHg
Wind11.7 mph NW
Humidity52%
Visibility—
Dew point37°
Mon, 0256° / 44°0
56 °
Castalia, Monday, 2 November
Overcast. High 56°, low 44°.
Pressure30.15 inHg
Wind8.3 mph SE
Humidity51%
Visibility—
Dew point36°
Tue, 0351° / 41°0
51 °
Castalia, Tuesday, 3 November
Overcast. High 51°, low 41°.
Pressure30.30 inHg
Wind11.3 mph N
Humidity69%
Visibility—
Dew point39°
Wed, 0449° / 39°0.03
49 °
Castalia, Wednesday, 4 November
Light rain. High 49°, low 39°.
Pressure30.09 inHg
Wind12.6 mph NW
Humidity58%
Visibility—
Dew point34°
Thu, 0554° / 35°0
54 °
Castalia, Thursday, 5 November
Overcast. High 54°, low 35°.
Pressure30.00 inHg
Wind14.8 mph W
Humidity47%
Visibility—
Dew point29°
Fri, 0658° / 43°0
58 °
Castalia, Friday, 6 November
Clear. High 58°, low 43°.
Pressure29.88 inHg
Wind12.3 mph NW
Humidity59%
Visibility—
Dew point42°
Sat, 0743° / 34°0
43 °
Castalia, Saturday, 7 November
Overcast. High 43°, low 34°.
Pressure30.09 inHg
Wind14.3 mph SE
Humidity52%
Visibility—
Dew point25°
From day 17 onward the outlook is built from 60-year climate statistics
Sun, 0847° / 33°0.03
47 °
Castalia, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high47°
Average low33°
Average precipitation0.03 in
Chance of precipitation15%
Record high73° (1999)
Record low-2° (1991)
Mon, 0947° / 33°0.11
47 °
Castalia, Monday, 9 November
Climate normal for this date — 60-year average.
Average high47°
Average low33°
Average precipitation0.11 in
Chance of precipitation37%
Record high70° (1999)
Record low15° (1991)
Tue, 1045° / 32°0.1
45 °
Castalia, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high45°
Average low32°
Average precipitation0.1 in
Chance of precipitation32%
Record high70° (2012)
Record low10° (2018)
Wed, 1144° / 30°0.09
44 °
Castalia, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high44°
Average low30°
Average precipitation0.09 in
Chance of precipitation23%
Record high68° (1964)
Record low10° (1986)
Thu, 1242° / 29°0.06
42 °
Castalia, Thursday, 12 November
Climate normal for this date — 60-year average.
Average high42°
Average low29°
Average precipitation0.06 in
Chance of precipitation30%
Record high63° (1964)
Record low5° (2019)
Fri, 1343° / 29°0.06
43 °
Castalia, Friday, 13 November
Climate normal for this date — 60-year average.
Average high43°
Average low29°
Average precipitation0.06 in
Chance of precipitation22%
Record high70° (1999)
Record low3° (1986)
Sat, 1444° / 30°0.02
44 °
Castalia, Saturday, 14 November
Climate normal for this date — 60-year average.
Average high44°
Average low30°
Average precipitation0.02 in
Chance of precipitation20%
Record high66° (2025)
Record low13° (1986)
Sun, 1544° / 31°0.06
44 °
Castalia, Sunday, 15 November
Climate normal for this date — 60-year average.
Average high44°
Average low31°
Average precipitation0.06 in
Chance of precipitation27%
Record high65° (2001)
Record low15° (2014)
Mon, 1644° / 30°0.06
44 °
Castalia, Monday, 16 November
Climate normal for this date — 60-year average.
Average high44°
Average low30°
Average precipitation0.06 in
Chance of precipitation30%
Record high62° (2023)
Record low13° (1997)
Tue, 1744° / 31°0.09
44 °
Castalia, Tuesday, 17 November
Climate normal for this date — 60-year average.
Average high44°
Average low31°
Average precipitation0.09 in
Chance of precipitation22%
Record high68° (2016)
Record low9° (2014)
Wed, 1844° / 30°0.08
44 °
Castalia, Wednesday, 18 November
Climate normal for this date — 60-year average.
Average high44°
Average low30°
Average precipitation0.08 in
Chance of precipitation28%
Record high67° (1999)
Record low6° (2014)
Thu, 1943° / 29°0.07
43 °
Castalia, Thursday, 19 November
Climate normal for this date — 60-year average.
Average high43°
Average low29°
Average precipitation0.07 in
Chance of precipitation28%
Record high62° (1999)
Record low7° (1986)
Fri, 2041° / 29°0.09
41 °
Castalia, Friday, 20 November
Climate normal for this date — 60-year average.
Average high41°
Average low29°
Average precipitation0.09 in
Chance of precipitation30%
Record high62° (2003)
Record low10° (1964)
Sat, 2140° / 26°0.06
40 °
Castalia, Saturday, 21 November
Climate normal for this date — 60-year average.
Average high40°
Average low26°
Average precipitation0.06 in
Chance of precipitation22%
Record high67° (1990)
Record low3° (1964)
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 Castalia, 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 Castalia, 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.