As of 03:39 EDT

Weather in Siam, TN

61°Current weather

Siam, Monday, 12 October, 03:39

Overcast. Feels like 61°. High 80°, low 61°.

Pressure30.00 inHg
Wind6.9 mph SW
Humidity97%
Visibility4.7 mi
Dew point60°

Monthly outlook for Siam, TN: average high 68.3°, average low 48.4°. That is 1.7° above the climate normal for October. Precipitation is expected on 4 days (about 1.5 inches), against a normal of 5 days and 1.7 inches. The warmest day looks like 13 October (82.8°), the coolest 18 October (34.8°).

68.3°/48.4°
Average high / low
+1.7°
Above normal
4 / 5
Wet days / normal
1.5 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
12 October – 21 October74.4°66.1°+4.6°
22 October – 31 October58.2°63.2°-2.8°
1 November – 10 Novemberat normal59.7°—

October records over 66 years

91.4°3 October 2019All-time high
22.5°27 October 1982All-time low

Climate normals and records are computed from the nearest reference point — Johnson City (13 mi).

Tue, 1383° / 60°0Clear
83 °Clear

Siam, Tuesday, 13 October

Clear. High 83°, low 60°.

Pressure30.09 inHg
Wind5.8 mph SW
Humidity65%
Visibility6.2 mi
Dew point62°
Wed, 1479° / 59°0Clear
79 °Clear

Siam, Wednesday, 14 October

Clear. High 79°, low 59°.

Pressure30.12 inHg
Wind3.9 mph W
Humidity66%
Visibility4.3 mi
Dew point64°
Thu, 1581° / 62°0Overcast
81 °Overcast

Siam, Thursday, 15 October

Overcast. High 81°, low 62°.

Pressure30.15 inHg
Wind0.9 mph SW
Humidity69%
Visibility6.2 mi
Dew point68°
Fri, 1677° / 51°0.08Light rain
77 °Light rain

Siam, Friday, 16 October

Light rain. High 77°, low 51°.

Pressure29.97 inHg
Wind16.4 mph W
Humidity61%
Visibility—
Dew point61°
Sat, 1758° / 38°0Mostly clear
58 °Mostly clear

Siam, Saturday, 17 October

Mostly clear. High 58°, low 38°.

Pressure30.39 inHg
Wind7.3 mph N
Humidity44%
Visibility—
Dew point34°
Sun, 1865° / 35°0Clear
65 °Clear

Siam, Sunday, 18 October

Clear. High 65°, low 35°.

Pressure30.53 inHg
Wind6.7 mph SE
Humidity22%
Visibility—
Dew point22°
Mon, 1971° / 39°0Clear
71 °Clear

Siam, Monday, 19 October

Clear. High 71°, low 39°.

Pressure30.45 inHg
Wind6 mph SE
Humidity18%
Visibility—
Dew point22°
Tue, 2073° / 48°0Clear
73 °Clear

Siam, Tuesday, 20 October

Clear. High 73°, low 48°.

Pressure30.30 inHg
Wind5.3 mph SE
Humidity34%
Visibility—
Dew point40°
Wed, 2177° / 53°0Clear
77 °Clear

Siam, Wednesday, 21 October

Clear. High 77°, low 53°.

Pressure30.21 inHg
Wind5.5 mph SE
Humidity41%
Visibility—
Dew point48°
Thu, 2267° / 55°0.28Rain
67 °Rain

Siam, Thursday, 22 October

Rain. High 67°, low 55°.

Pressure30.06 inHg
Wind6.8 mph SE
Humidity89%
Visibility—
Dew point57°
Fri, 2358° / 47°1.04Heavy rain
58 °Heavy rain

Siam, Friday, 23 October

Heavy rain. High 58°, low 47°.

Pressure29.88 inHg
Wind13.6 mph W
Humidity41%
Visibility—
Dew point33°
Sat, 2453° / 39°0.01Light rain
53 °Light rain

Siam, Saturday, 24 October

Light rain. High 53°, low 39°.

Pressure29.97 inHg
Wind10.7 mph NW
Humidity44%
Visibility—
Dew point30°
Sun, 2559° / 36°0Overcast
59 °Overcast

Siam, Sunday, 25 October

Overcast. High 59°, low 36°.

Pressure29.91 inHg
Wind5.8 mph W
Humidity38%
Visibility—
Dew point29°
Mon, 2662° / 46°0.01Light rain
62 °Light rain

Siam, Monday, 26 October

Light rain. High 62°, low 46°.

Pressure29.80 inHg
Wind10.3 mph W
Humidity61%
Visibility—
Dew point47°
Tue, 2750° / 47°0Overcast
50 °Overcast

Siam, Tuesday, 27 October

Overcast. High 50°, low 47°.

Pressure30.00 inHg
Wind6.8 mph W
Humidity72%
Visibility—
Dew point41°
From day 17 onward the outlook is built from 60-year climate statistics
Wed, 2862° / 46°0.13Climate normal
62 °Climate normal

Siam, Wednesday, 28 October

Climate normal for this date — 60-year average.

Average high62°
Average low46°
Average precipitation0.13 in
Chance of precipitation40%
Record high78° (1991)
Record low26° (1976)
Thu, 2962° / 44°0.12Climate normal
62 °Climate normal

Siam, Thursday, 29 October

Climate normal for this date — 60-year average.

Average high62°
Average low44°
Average precipitation0.12 in
Chance of precipitation30%
Record high78° (2023)
Record low29° (1976)
Fri, 3063° / 43°0.13Climate normal
63 °Climate normal

Siam, Friday, 30 October

Climate normal for this date — 60-year average.

Average high63°
Average low43°
Average precipitation0.13 in
Chance of precipitation28%
Record high77° (2024)
Record low28° (2017)
Sat, 3164° / 45°0.08Climate normal
64 °Climate normal

Siam, Saturday, 31 October

Climate normal for this date — 60-year average.

Average high64°
Average low45°
Average precipitation0.08 in
Chance of precipitation30%
Record high78° (2024)
Record low32° (1993)
Sun, 0163° / 45°0.09Climate normal
63 °Climate normal

Siam, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high63°
Average low45°
Average precipitation0.09 in
Chance of precipitation35%
Record high78° (2016)
Record low28° (2023)
Mon, 0262° / 44°0.15Climate normal
62 °Climate normal

Siam, Monday, 2 November

Climate normal for this date — 60-year average.

Average high62°
Average low44°
Average precipitation0.15 in
Chance of precipitation35%
Record high78° (2004)
Record low24° (2023)
Tue, 0361° / 43°0.08Climate normal
61 °Climate normal

Siam, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high61°
Average low43°
Average precipitation0.08 in
Chance of precipitation27%
Record high77° (2003)
Record low24° (2014)
Wed, 0459° / 42°0.14Climate normal
59 °Climate normal

Siam, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high59°
Average low42°
Average precipitation0.14 in
Chance of precipitation37%
Record high77° (2003)
Record low25° (1966)
Thu, 0559° / 41°0.13Climate normal
59 °Climate normal

Siam, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high59°
Average low41°
Average precipitation0.13 in
Chance of precipitation32%
Record high75° (2022)
Record low25° (1991)
Fri, 0659° / 41°0.06Climate normal
59 °Climate normal

Siam, Friday, 6 November

Climate normal for this date — 60-year average.

Average high59°
Average low41°
Average precipitation0.06 in
Chance of precipitation33%
Record high79° (2024)
Record low25° (1967)
Sat, 0759° / 41°0.14Climate normal
59 °Climate normal

Siam, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high59°
Average low41°
Average precipitation0.14 in
Chance of precipitation32%
Record high77° (2024)
Record low26° (1967)
Sun, 0858° / 40°0.1Climate normal
58 °Climate normal

Siam, Sunday, 8 November

Climate normal for this date — 60-year average.

Average high58°
Average low40°
Average precipitation0.1 in
Chance of precipitation28%
Record high78° (2023)
Record low25° (1971)
Mon, 0959° / 40°0.09Climate normal
59 °Climate normal

Siam, Monday, 9 November

Climate normal for this date — 60-year average.

Average high59°
Average low40°
Average precipitation0.09 in
Chance of precipitation25%
Record high76° (2023)
Record low25° (1995)
Tue, 1058° / 40°0.13Climate normal
58 °Climate normal

Siam, Tuesday, 10 November

Climate normal for this date — 60-year average.

Average high58°
Average low40°
Average precipitation0.13 in
Chance of precipitation38%
Record high74° (2006)
Record low25° (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 Siam, TN 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 Siam, TN 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.