Climate · Lyndon

Lyndon, IL climate

Lyndon has cold winters and warm summers. A typical July afternoon reaches 84°, a January night drops to 14°, and about 30 inches of snow falls in a normal winter.

NOAA 1991-2020 climate normals Updated once a decade
July high
84°
836th coolest of 2,886 Illinois towns
January low
14°
262nd coldest of 2,886 Illinois towns
Rain + melted snow
39 in
1121st driest of 2,886 Illinois towns
Snow a winter
30 in
600th snowiest of 2,880 Illinois towns
A normal year

What a year in Lyndon feels like

Winter

33° / 17°
Typical high / low · 11 days with an inch or more of snow

Spring

61° / 39°
Typical high / low · Last frost around Apr 26

Summer

83° / 61°
Typical high / low · 17 days reach 90° in a normal year

Fall

63° / 42°
Typical high / low · First frost around Oct 13
Best months to be outsideMayJunAugSepOctHighs of 62–84° and lows of 40° or more
Month by month

Lyndon weather by month

Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.

MonthHighLowRain + meltSnowWet daysSnow on ground30-yr range
January30°14°1.6" 9.5"719 13° – 34°
February35°18°1.7" 6.6"612 13° – 37°
March48°28°2.5" 3.0"84 30° – 53°
April61°38°3.8" 0.7"100 41° – 57°
May72°50°4.6" 0110 55° – 67°
June81°60°5.0" 0100 68° – 74°
July84°63°4.1" 070 68° – 80°
August82°61°4.0" 080 66° – 78°
September76°53°3.9" 060 59° – 70°
October64°41°2.9" 0.1"80 48° – 58°
November48°30°2.4" 1.5"61 31° – 48°
December35°20°2.1" 8.2"710 14° – 38°
Year60°40°38.5"29.6"9546

“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.

Rain & snow

Rain and snow in Lyndon

Lyndon gets 39 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 95 days a year. Snow covers the ground about 46 days of the year.

39 in
Rain + melted snow a year
Less rain than 54% of U.S. towns
30 in
Snow in a normal winter
More snow than 57% of U.S. towns
46 days
With 1"+ of snow on the ground
More than 63% of U.S. towns

Rain + melted snow by month

Inches of water
5.0"

Snowfall by month

Inches of snow
9.5"
Frost & the growing season

About 167 frost-free days a year

In half of years the last 32° night comes by April 26 and the first one by October 13. That leaves about 167 frost-free days for gardens, shorter than 64% of U.S. towns.

145
nights at or below 32° in a normal year
14
nights below 0° in a normal year
17
days that reach 90° in a normal year

Freezing nights by month

Average nights at or below 32°

90° days by month

Average days at 90° or more
Heating & cooling

Heating and cooling a home in Lyndon

Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Lyndon, 91% of that work is heating and 9% is cooling, so the furnace matters far more than the air conditioner.

91%heating
6,747 heating degree daysMore heating than 69% of U.S. towns
705 cooling degree daysLess cooling than 60% of U.S. towns

Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.

Compared with other towns

How Lyndon compares

Summer heat84° July high
Cooler than 53% of U.S. towns836th coolest of 2,886 Illinois towns
Winter cold14° January low
Colder than 74% of U.S. towns262nd coldest of 2,886 Illinois towns
Precipitation39" a year
Drier than 54% of U.S. towns1121st driest of 2,886 Illinois towns
Snow30" a winter
Snowier than 57% of U.S. towns600th snowiest of 2,880 Illinois towns
Growing season167 frost-free days
Shorter than 64% of U.S. towns192nd shortest of 2,886 Illinois towns

Compared with every U.S. town and city on TownTapestry, each counted once.

Then and now

Warmer than it used to be

+1.3°1991–2020 average vs. the 20th century (1901–2000)

The last 30 years in Lyndon averaged 1.3° warmer than the 1900s. The biggest change is in December (+2.7°). The shift is larger than in 60% of U.S. towns.

❄️ Winter+2.1° now 25°, was 23°
🌷 Spring+1.5° now 50°, was 48°
☀️ Summer+0.6° now 72°, was 71°
🍂 Fall+1.1° now 52°, was 51°

Change by month1991–2020 average minus 1901–2000 average, at Lyndon’s spot on NOAA’s grid

Year to year

How much a month can swing

A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 13° to 37°. June is the most reliable, staying within 7°.

Coldest to warmest month in 30 yearsNormal
Questions

Common questions about Lyndon’s climate

What is the coldest month in Lyndon?

January, with a typical high of 30° and a low of 14°.

What is the hottest month in Lyndon?

July, with a typical high of 84° and a low of 63°. About 17 days a year reach 90°.

How much snow does Lyndon get?

About 30 inches in a normal winter, most of it in January.

When is the first frost in Lyndon?

In half of years the first 32° night comes by October 13, and the last spring frost by April 26.

What is the rainiest month in Lyndon?

June, with 5.0 inches of rain and melted snow. The year totals 39 inches.

Temperatures and rainfall come from NOAA’s gridded climate normals for Lyndon itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Prophetstown, IL (3 mi, snow) and Morrison, IL (6 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.

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