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Lancaster weather by month: averages, rainfall & climate trends

Lancaster has well-marked seasons, with 33.3°F between its warmest and coolest monthly means. Precipitation is scarce in every season. Lancaster weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+1.3°Fhigh near average

76° / 45°Today
75° / 52°Average
see today in detail →

How it's changed

+5.1°Faverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–492frost days a year now (2016–2025) · 23 in the 1940sfrost days a year · 23 in the 1940s122days above 86°F a year now (2016–2025) · 100 in the 1940sdays above 86°F · 100 in the 1940s+5.1°F vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 1.5 incheshigh 57°low 39°February, rain 1.7 incheshigh 61°low 41°March, rain 1.4 incheshigh 65°low 44°April, rain 0.6 incheshigh 72°low 48°May, rain 0.2 incheshigh 80°low 54°June, rain 0.05 incheshigh 88°low 61°July, rain 0.1 incheshigh 94°low 67°August, rain 0.1 incheshigh 93°low 66°September, rain 0.2 incheshigh 88°low 62°October, rain 0.3 incheshigh 78°low 54°November, rain 0.7 incheshigh 66°low 45°December, rain 1.2 incheshigh 58°low 40°wettest month February, 1.7 inches · 8.0 inches a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Clear

Right now

75.0°

69°feels like
22%humidity
34°dew point
5 mphfrom W
UV index1.2
sunrise07:07sunset18:05day length10h 59m
TodayClear76°45°
MonClear76°48°
TueClear73°46°
WedOvercast69°53°
ThuOvercast69°57°
FriMostly clear68°54°
SatOvercast65°53°

On this date: October 25

Today (forecast)
76° / 45°
Average for October 25
75° / 52°

High near average · +1.3°F

  • Highest since 1940: 87.1° · 1959
  • Lowest since 1940: 39.1° · 1971
  • One year ago: 81° / 54°

Every October 25 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 25 on record (n = 87). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Lancaster is sampled from the ECMWF ERA5 reanalysis at 34.70°N, 118.14°W, with daily records since 1940.

Coordinates
34.70°N, 118.14°W
Time zone
America/Los Angeles
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

22 of the last 31 days were warmer than the historical average for that date. Average difference: +3.1°F.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

The year peaks in July, at around 94.1°F by mid-afternoon, with nights around 66.9°F. Roughly 120 days a year now top 86°F. The coolest month is January, when afternoons reach about 57.5°F and overnight lows sit around 39.1°F.

Lancaster averages only about 8.0 inches a year, and what little falls comes mostly around February.

Over the full record (since 1940), the annual mean temperature in Lancaster has risen by 5.1°F between its first decade and its last. Where the first decade averaged 25 frost days a year, the recent one saw about 2.

Climate graph (climograph)

July is the warmest month, January the coolest: a yearly swing of 33°F. Wettest month: February (~1.7 in). Whole year averages ~8.0 inches of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 20 rainy days a year: most in March (~4), fewest in June (almost none).

Bars = average number of days with ≥ 0.08 in per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Lancaster month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January57.5°39.1°1.5 in49.9 h75.2° (2003)13.6° (1949)
February60.7°41.2°1.7 in410.7 h81.3° (2014)17.8° (1979)
March65.4°43.9°1.4 in411.7 h86.2° (1990)20.2° (1951)
April72.3°48.3°0.6 in212.9 h94.0° (1989)31.5° (1945)
May79.9°54.5°0.2 in013.8 h101.6° (1984)37.9° (1964)
June88.1°61.1°0.05 in014.3 h107.8° (2021)43.3° (1967)
July94.1°66.9°0.1 in014.1 h109.9° (2024)51.8° (1948)
August93.1°66.5°0.1 in013.3 h107.5° (2020)51.3° (1947)
September87.9°62.3°0.2 in012.2 h108.4° (2020)44.0° (1948)
October77.7°54.0°0.3 in111.1 h100.4° (2024)32.3° (1971)
November65.7°45.0°0.7 in210.1 h84.4° (1955)17.3° (1964)
December57.8°39.5°1.2 in39.7 h78.3° (1958)15.9° (1990)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +5.1°F.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.54°F per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Dec–Feb is warming fastest: +0.68°F per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 86°F per year: 99.6 early in the record → 121.8 recently. Frost days: 23 → 2.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2024, coldest in 1949: 109.9°F / 13.6°F.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~8.0 in/year on average. Last decade: +11% vs that average. Long-term trend: +0.05 in per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Lancaster

Which is the warmest month in Lancaster?
On long-term average, the warmest month in Lancaster is July (mean daily temperature of about 79.9°F) and the coolest is January (about 46.6°F).
How does today's temperature in Lancaster compare to the historical average?
On October 25, 2026, Lancaster is forecast to reach a high of 76.1°F and a low of 44.6°F. The long-term average for this date (the full record since 1940) is a high of 74.8°F and a low of 52.3°F, so today's high is 1.3°F warmer than that average.
How much has Lancaster warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Lancaster is about 5.1°F warmer.
How much does it rain in Lancaster?
Lancaster receives about 8.0 inches of precipitation per year on long-term average, with February typically the wettest month.
What is the average temperature in Lancaster?
Over the full record (since 1940), the annual mean temperature in Lancaster is about 62.2°F. The warmest month is July and the coolest is January.
What are the average temperatures in Lancaster by month?
Average daily highs and lows for each month in Lancaster (°F, full record since 1940): January 57°/39°, February 61°/41°, March 65°/44°, April 72°/48°, May 80°/54°, June 88°/61°, July 94°/67°, August 93°/66°, September 88°/62°, October 78°/54°, November 66°/45°, December 58°/40°.
What is the weather like in Lancaster in summer?
Summer in Lancaster (June to August) is dry and hot. Daytime highs sit at 88–94°F and nights at 61–67°F; July is the warmest month. Almost no rain.
What is the weather like in Lancaster in winter?
In winter, December through February, Lancaster is cool. Afternoons run 57–61°F and nights 39–41°F; January is the coldest month. Rain falls on about 3 days a month, adding up to around 1.5 inches. No season is wetter.
What is the weather like in Lancaster in spring?
March to May is spring in Lancaster, and it is dry and pleasantly warm. It warms from 65°F by day and 44°F at night in March to 80°F and 54°F in May. Rain falls off from 1.4 inches in March to 0.2 inches in May.
What is the weather like in Lancaster in autumn?
In autumn, September through November, Lancaster is dry and pleasantly warm. September is still 88°F by day and 62°F at night; by November it is down to 66°F and 45°F. Rain picks up through the season, 0.2 inches in September to 0.7 inches in November.
How many days a year does it rain in Lancaster?
On long-term average, Lancaster has about 20 days a year with at least 0.08 inches of rain or snow. The annual total is roughly 8.0 inches.

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