As of 18:44 CDT

Weather in Sinai, SD

65°

Sinai, Wednesday, 21 October, 18:44

Overcast. Feels like 65°. High 70°, low 45°.

Pressure30.15 inHg

Wind6.2 mph NE

Humidity71%

Visibility6.2 mi

Dew point56°

See detailed hourly forecast

Monthly outlook for Sinai, SD: average high 55.5°, average low 42°. That is 2.5° above the climate normal for October. Precipitation is expected on 7 days (about 2.1 inches), against a normal of 3 days and 0.8 inches. The warmest day looks like 22 October (73.9°), the coolest 29 October (28.3°).

55.5°/42°

Average high / low

+2.5°

Above normal

7 / 3

Wet days / normal

2.1 in

Precipitation this month

Ten-day blocks vs climate normal

Period	Forecast high	Normal	Difference
21 October – 30 October	55.6°	52.9°	+1.5°
31 October – 9 November	55.4°	47.1°	+4.6°
10 November – 19 November	at normal	41.1°	—

October records over 66 years

88.5°3 October 2025All-time high

8.2°26 October 2020All-time low

Climate normals and records are computed from the nearest reference point — Nunda (6 mi).

Thu, 2274° / 45°

74 °

Sinai, Thursday, 22 October

Mostly clear. High 74°, low 45°.

Pressure30.15 inHg

Wind8.2 mph SE

Humidity71%

Visibility6.2 mi

Dew point56°

Fri, 2370° / 53°

0.01

70 °

Sinai, Friday, 23 October

Light rain. High 70°, low 53°.

Pressure29.97 inHg

Wind17.7 mph S

Humidity65%

Visibility6.2 mi

Dew point53°

Sat, 2463° / 49°

0.14

63 °

Sinai, Saturday, 24 October

Rain. High 63°, low 49°.

Pressure30.18 inHg

Wind11.9 mph NW

Humidity62%

Visibility6.2 mi

Dew point47°

Sun, 2548° / 44°

0.19

48 °

Sinai, Sunday, 25 October

Light rain. High 48°, low 44°.

Pressure30.39 inHg

Wind9.7 mph NE

Humidity70%

Visibility6.2 mi

Dew point38°

Mon, 2643° / 41°

0.86

43 °

Sinai, Monday, 26 October

Rain. High 43°, low 41°.

Pressure30.30 inHg

Wind14 mph N

Humidity88%

Visibility—

Dew point40°

Tue, 2740° / 36°

0.17

40 °

Sinai, Tuesday, 27 October

Light rain. High 40°, low 36°.

Pressure30.33 inHg

Wind11 mph N

Humidity91%

Visibility—

Dew point35°

Wed, 2846° / 35°

0.08

46 °

Sinai, Wednesday, 28 October

Light snow. High 46°, low 35°.

Pressure30.30 inHg

Wind13.9 mph NW

Humidity54%

Visibility—

Dew point28°

Thu, 2947° / 28°

47 °

Sinai, Thursday, 29 October

Clear. High 47°, low 28°.

Pressure30.39 inHg

Wind8.7 mph SW

Humidity43%

Visibility—

Dew point20°

Fri, 3055° / 38°

55 °

Sinai, Friday, 30 October

Overcast. High 55°, low 38°.

Pressure29.85 inHg

Wind14.7 mph S

Humidity67%

Visibility—

Dew point39°

Sat, 3166° / 44°

66 °

Sinai, Saturday, 31 October

Mostly clear. High 66°, low 44°.

Pressure29.85 inHg

Wind8.6 mph SW

Humidity34%

Visibility—

Dew point32°

Sun, 0154° / 51°

0.29

54 °

Sinai, Sunday, 1 November

Rain. High 54°, low 51°.

Pressure30.09 inHg

Wind8.1 mph SE

Humidity98%

Visibility—

Dew point54°

Mon, 0255° / 52°

0.37

55 °

Sinai, Monday, 2 November

Light rain. High 55°, low 52°.

Pressure30.03 inHg

Wind14.1 mph NE

Humidity98%

Visibility—

Dew point52°

Tue, 0352° / 40°

52 °

Sinai, Tuesday, 3 November

Overcast. High 52°, low 40°.

Pressure30.27 inHg

Wind15 mph NE

Humidity49%

Visibility—

Dew point32°

Wed, 0449° / 33°

49 °

Sinai, Wednesday, 4 November

Clear. High 49°, low 33°.

Pressure30.30 inHg

Wind10 mph S

Humidity44%

Visibility—

Dew point24°

Thu, 0556° / 37°

56 °

Sinai, Thursday, 5 November

Clear. High 56°, low 37°.

Pressure30.03 inHg

Wind9.9 mph S

Humidity62%

Visibility—

Dew point38°

From day 17 onward the outlook is built from 60-year climate statistics

Fri, 0647° / 32°

0.04

47 °

Sinai, Friday, 6 November

Climate normal for this date — 60-year average.

Average high47°

Average low32°

Average precipitation0.04 in

Chance of precipitation20%

Record high74° (2020)

Record low-2° (1991)

Sat, 0747° / 31°

0.02

47 °

Sinai, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high47°

Average low31°

Average precipitation0.02 in

Chance of precipitation12%

Record high71° (2020)

Record low-8° (1991)

Sun, 0846° / 31°

0.06

46 °

Sinai, Sunday, 8 November

Climate normal for this date — 60-year average.

Average high46°

Average low31°

Average precipitation0.06 in

Chance of precipitation15%

Record high72° (1999)

Record low4° (1991)

Mon, 0944° / 30°

0.13

44 °

Sinai, Monday, 9 November

Climate normal for this date — 60-year average.

Average high44°

Average low30°

Average precipitation0.13 in

Chance of precipitation20%

Record high67° (1999)

Record low13° (2018)

Tue, 1041° / 27°

0.06

41 °

Sinai, Tuesday, 10 November

Climate normal for this date — 60-year average.

Average high41°

Average low27°

Average precipitation0.06 in

Chance of precipitation20%

Record high63° (2016)

Record low5° (1986)

Wed, 1140° / 26°

0.03

40 °

Sinai, Wednesday, 11 November

Climate normal for this date — 60-year average.

Average high40°

Average low26°

Average precipitation0.03 in

Chance of precipitation20%

Record high62° (2005)

Record low0° (1986)

Thu, 1240° / 26°

0.06

40 °

Sinai, Thursday, 12 November

Climate normal for this date — 60-year average.

Average high40°

Average low26°

Average precipitation0.06 in

Chance of precipitation23%

Record high64° (2005)

Record low-2° (1966)

Fri, 1342° / 28°

0.03

42 °

Sinai, Friday, 13 November

Climate normal for this date — 60-year average.

Average high42°

Average low28°

Average precipitation0.03 in

Chance of precipitation20%

Record high67° (1999)

Record low-5° (1986)

Sat, 1442° / 29°

0.03

42 °

Sinai, Saturday, 14 November

Climate normal for this date — 60-year average.

Average high42°

Average low29°

Average precipitation0.03 in

Chance of precipitation17%

Record high68° (2025)

Record low5° (2014)

Sun, 1542° / 28°

0.04

42 °

Sinai, Sunday, 15 November

Climate normal for this date — 60-year average.

Average high42°

Average low28°

Average precipitation0.04 in

Chance of precipitation17%

Record high63° (2001)

Record low11° (2000)

Mon, 1642° / 28°

0.06

42 °

Sinai, Monday, 16 November

Climate normal for this date — 60-year average.

Average high42°

Average low28°

Average precipitation0.06 in

Chance of precipitation18%

Record high67° (2001)

Record low0° (2014)

Tue, 1741° / 27°

0.05

41 °

Sinai, Tuesday, 17 November

Climate normal for this date — 60-year average.

Average high41°

Average low27°

Average precipitation0.05 in

Chance of precipitation18%

Record high64° (2001)

Record low4° (2014)

Wed, 1840° / 27°

0.07

40 °

Sinai, Wednesday, 18 November

Climate normal for this date — 60-year average.

Average high40°

Average low27°

Average precipitation0.07 in

Chance of precipitation25%

Record high65° (1999)

Record low3° (1996)

Thu, 1940° / 26°

0.09

40 °

Sinai, Thursday, 19 November

Climate normal for this date — 60-year average.

Average high40°

Average low26°

Average precipitation0.09 in

Chance of precipitation25%

Record high58° (2003)

Record low7° (1996)

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 Sinai, SD 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 Sinai, SD 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.