As of 14:25 CDT

Weather in Jefferson, SD

79°Current weather

Jefferson, Saturday, 8 August, 14:25

Overcast. Feels like 79°. High 84°, low 59°.

Pressure30.00 inHg
Wind12.1 mph S
Humidity51%
Visibility6.2 mi
Dew point58°

Monthly outlook for Jefferson, SD: average high 94.3°, average low 65.3°. That is 6.7° above the climate normal for August. Precipitation is expected on 4 days (about 0.6 inches), against a normal of 5 days and 1.9 inches. The warmest day looks like 10 August (106.9°), the coolest 23 August (51.1°).

94.3°/65.3°
Average high / low
+6.7°
Above normal
4 / 5
Wet days / normal
0.6 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
8 August – 17 August95.3°82.2°+7.3°
18 August – 27 August92.6°82.2°+5.8°
28 August – 6 Septemberat normal81°

August records over 66 years

102.6°2 August 2022All-time high
44.8°28 August 1986All-time low

Climate normals and records are computed from the nearest reference point — Sioux City (12 mi).

Sun, 0990° / 72°0Partly cloudy
90 °Partly cloudy

Jefferson, Sunday, 9 August

Partly cloudy. High 90°, low 72°.

Pressure29.71 inHg
Wind8.2 mph N
Humidity28%
Visibility6.2 mi
Dew point60°
Mon, 10107° / 68°0Overcast
107 °Overcast

Jefferson, Monday, 10 August

Overcast. High 107°, low 68°.

Pressure29.77 inHg
Wind9 mph SE
Humidity28%
Visibility6.2 mi
Dew point60°
Tue, 11103° / 68°0.01Light rain
103 °Light rain

Jefferson, Tuesday, 11 August

Light rain. High 103°, low 68°.

Pressure29.74 inHg
Wind12.9 mph N
Humidity31%
Visibility6.2 mi
Dew point60°
Wed, 12103° / 72°0.01Light rain
103 °Light rain

Jefferson, Wednesday, 12 August

Light rain. High 103°, low 72°.

Pressure29.80 inHg
Wind10.4 mph SE
Humidity30%
Visibility6.2 mi
Dew point59°
Thu, 1390° / 64°0.16Light rain
90 °Light rain

Jefferson, Thursday, 13 August

Light rain. High 90°, low 64°.

Pressure29.94 inHg
Wind13.6 mph E
Humidity30%
Visibility
Dew point48°
Fri, 1490° / 59°0Overcast
90 °Overcast

Jefferson, Friday, 14 August

Overcast. High 90°, low 59°.

Pressure30.15 inHg
Wind11.5 mph S
Humidity25%
Visibility
Dew point42°
Sat, 1590° / 60°0Overcast
90 °Overcast

Jefferson, Saturday, 15 August

Overcast. High 90°, low 60°.

Pressure30.09 inHg
Wind14.5 mph SE
Humidity37%
Visibility
Dew point54°
Sun, 1699° / 69°0.13Light rain
99 °Light rain

Jefferson, Sunday, 16 August

Light rain. High 99°, low 69°.

Pressure29.94 inHg
Wind11.7 mph S
Humidity46%
Visibility
Dew point65°
Mon, 1798° / 70°0.08Light rain
98 °Light rain

Jefferson, Monday, 17 August

Light rain. High 98°, low 70°.

Pressure29.97 inHg
Wind9.9 mph N
Humidity43%
Visibility
Dew point65°
Tue, 18102° / 69°0Overcast
102 °Overcast

Jefferson, Tuesday, 18 August

Overcast. High 102°, low 69°.

Pressure29.91 inHg
Wind9.8 mph SW
Humidity33%
Visibility
Dew point59°
Wed, 19102° / 70°0.11Light rain
102 °Light rain

Jefferson, Wednesday, 19 August

Light rain. High 102°, low 70°.

Pressure29.83 inHg
Wind15.7 mph E
Humidity28%
Visibility
Dew point55°
Thu, 2091° / 65°0.03Light rain
91 °Light rain

Jefferson, Thursday, 20 August

Light rain. High 91°, low 65°.

Pressure29.94 inHg
Wind9.4 mph NE
Humidity30%
Visibility
Dew point50°
Fri, 2196° / 65°0Clear
96 °Clear

Jefferson, Friday, 21 August

Clear. High 96°, low 65°.

Pressure29.91 inHg
Wind11.3 mph W
Humidity28%
Visibility
Dew point51°
Sat, 2282° / 66°0.02Light rain
82 °Light rain

Jefferson, Saturday, 22 August

Light rain. High 82°, low 66°.

Pressure30.00 inHg
Wind16.5 mph NE
Humidity54%
Visibility
Dew point57°
Sun, 2383° / 51°0Clear
83 °Clear

Jefferson, Sunday, 23 August

Clear. High 83°, low 51°.

Pressure30.15 inHg
Wind11.3 mph SE
Humidity24%
Visibility
Dew point35°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2482° / 66°0.05Climate normal
82 °Climate normal

Jefferson, Monday, 24 August

Climate normal for this date — 60-year average.

Average high82°
Average low66°
Average precipitation0.05 in
Chance of precipitation18%
Record high99° (2023)
Record low52° (2015)
Tue, 2582° / 65°0.09Climate normal
82 °Climate normal

Jefferson, Tuesday, 25 August

Climate normal for this date — 60-year average.

Average high82°
Average low65°
Average precipitation0.09 in
Chance of precipitation20%
Record high97° (1991)
Record low50° (2015)
Wed, 2682° / 65°0.11Climate normal
82 °Climate normal

Jefferson, Wednesday, 26 August

Climate normal for this date — 60-year average.

Average high82°
Average low65°
Average precipitation0.11 in
Chance of precipitation37%
Record high95° (1976)
Record low53° (1988)
Thu, 2782° / 65°0.09Climate normal
82 °Climate normal

Jefferson, Thursday, 27 August

Climate normal for this date — 60-year average.

Average high82°
Average low65°
Average precipitation0.09 in
Chance of precipitation28%
Record high96° (1984)
Record low51° (1986)
Fri, 2882° / 64°0.14Climate normal
82 °Climate normal

Jefferson, Friday, 28 August

Climate normal for this date — 60-year average.

Average high82°
Average low64°
Average precipitation0.14 in
Chance of precipitation25%
Record high99° (1984)
Record low45° (1986)
Sat, 2982° / 64°0.07Climate normal
82 °Climate normal

Jefferson, Saturday, 29 August

Climate normal for this date — 60-year average.

Average high82°
Average low64°
Average precipitation0.07 in
Chance of precipitation18%
Record high98° (2012)
Record low51° (2018)
Sun, 3082° / 64°0.09Climate normal
82 °Climate normal

Jefferson, Sunday, 30 August

Climate normal for this date — 60-year average.

Average high82°
Average low64°
Average precipitation0.09 in
Chance of precipitation30%
Record high101° (2012)
Record low50° (2009)
Mon, 3181° / 64°0.09Climate normal
81 °Climate normal

Jefferson, Monday, 31 August

Climate normal for this date — 60-year average.

Average high81°
Average low64°
Average precipitation0.09 in
Chance of precipitation32%
Record high92° (1990)
Record low49° (1967)
Tue, 0181° / 63°0.08Climate normal
81 °Climate normal

Jefferson, Tuesday, 1 September

Climate normal for this date — 60-year average.

Average high81°
Average low63°
Average precipitation0.08 in
Chance of precipitation28%
Record high92° (1970)
Record low48° (1974)
Wed, 0281° / 63°0.08Climate normal
81 °Climate normal

Jefferson, Wednesday, 2 September

Climate normal for this date — 60-year average.

Average high81°
Average low63°
Average precipitation0.08 in
Chance of precipitation28%
Record high96° (2023)
Record low50° (1974)
Thu, 0380° / 63°0.13Climate normal
80 °Climate normal

Jefferson, Thursday, 3 September

Climate normal for this date — 60-year average.

Average high80°
Average low63°
Average precipitation0.13 in
Chance of precipitation27%
Record high95° (2023)
Record low42° (1974)
Fri, 0480° / 62°0.11Climate normal
80 °Climate normal

Jefferson, Friday, 4 September

Climate normal for this date — 60-year average.

Average high80°
Average low62°
Average precipitation0.11 in
Chance of precipitation22%
Record high96° (2012)
Record low46° (1974)
Sat, 0580° / 62°0.08Climate normal
80 °Climate normal

Jefferson, Saturday, 5 September

Climate normal for this date — 60-year average.

Average high80°
Average low62°
Average precipitation0.08 in
Chance of precipitation32%
Record high94° (1990)
Record low42° (1962)
Sun, 0681° / 62°0.05Climate normal
81 °Climate normal

Jefferson, Sunday, 6 September

Climate normal for this date — 60-year average.

Average high81°
Average low62°
Average precipitation0.05 in
Chance of precipitation17%
Record high99° (1976)
Record low44° (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 Jefferson, 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 Jefferson, 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.