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Plano weather by month: averages, rainfall & climate trends

Seasons run to extremes in Plano: monthly means span 40.0°F between the coldest month and the warmest. The heavier rain months run from March to May. Plano weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+1.5°Fhigh near average

79° / 53°Today
77° / 56°Average
see today in detail →

How it's changed

+3.2°Faverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4920frost days a year now (2016–2025) · 25 in the 1940sfrost days a year · 25 in the 1940s129days above 86°F a year now (2016–2025) · 90 in the 1940sdays above 86°F · 90 in the 1940s+3.2°F vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 2.4 incheshigh 55°low 36°February, rain 2.9 incheshigh 59°low 40°March, rain 3.8 incheshigh 67°low 47°April, rain 4.8 incheshigh 75°low 56°May, rain 5.7 incheshigh 82°low 64°June, rain 3.2 incheshigh 89°low 72°July, rain 1.8 incheshigh 93°low 75°August, rain 1.9 incheshigh 94°low 75°September, rain 2.8 incheshigh 87°low 68°October, rain 3.5 incheshigh 78°low 58°November, rain 3.5 incheshigh 66°low 47°December, rain 2.9 incheshigh 58°low 40°wettest month May, 5.7 inches · 39.2 inches a yearsee month by month →

Right now

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

Right now

78.4°

74°feels like
23%humidity
38°dew point
6 mphfrom E
UV index5.8
sunrise07:35sunset18:47day length11h 13m
TodayOvercast79°53°
WedClear80°50°
ThuClear83°58°
FriOvercast82°65°
SatOvercast81°66°
SunOvercast78°64°
MonOvercast78°62°

On this date: October 20

Today (forecast)
79° / 53°
Average for October 20
77° / 56°

High near average · +1.5°F

  • Highest since 1940: 91.6° · 2023
  • Lowest since 1940: 34.3° · 1989
  • One year ago: 89° / 55°

Every October 20 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 20 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 Plano is sampled from the ECMWF ERA5 reanalysis at 33.02°N, 96.70°W, with daily records since 1940.

Coordinates
33.02°N, 96.70°W
Time zone
America/Chicago
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

25 of the last 31 days were warmer than the historical average for that date. Average difference: +5.4°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 warmest month is August, with typical afternoon highs of 93.7°F and nights around 74.9°F. On about 130 nights a year, the temperature never drops below 68°F. At the other extreme, January brings afternoon highs of about 55.0°F and typical overnight lows of 36.5°F. Around 20 days a year dip below freezing.

In total, Plano averages about 39.2 inches of precipitation a year; May is usually the wettest month (5.7 inches) and July the driest (1.8 inches).

Over the full record (since 1940), the annual mean temperature in Plano has risen by 3.2°F between its first decade and its last. The count of days past 86°F has risen from roughly 90 a year to 130 between the record's first and last decades.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 40°F. Wettest month: May (~5.7 in). Whole year averages ~39.2 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 74 rainy days a year: most in May (~9), fewest in August (~4).

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.

Plano 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
January55.0°36.5°2.4 in510.0 h81.9° (2006)6.5° (1982)
February59.4°40.3°2.9 in610.8 h89.4° (2024)−1.3° (2021)
March67.4°47.4°3.8 in811.8 h95.7° (1974)14.8° (2014)
April75.3°55.8°4.8 in812.8 h96.8° (2006)30.4° (1975)
May81.7°64.0°5.7 in913.7 h98.0° (1985)39.7° (2013)
June88.8°71.6°3.2 in614.2 h103.6° (1980)53.2° (1964)
July93.3°75.1°1.8 in414.0 h106.4° (2022)60.5° (1971)
August93.7°74.9°1.9 in413.2 h107.9° (2023)56.3° (1992)
September87.1°68.2°2.8 in512.2 h107.2° (2000)42.0° (1984)
October77.6°57.9°3.5 in611.2 h95.4° (2020)27.1° (1993)
November65.8°47.2°3.5 in610.3 h90.8° (2017)19.5° (1976)
December57.5°39.6°2.9 in69.8 h87.4° (1955)−1.5° (1989)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +3.2°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: +0.36°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

Mar–May is warming fastest: +0.46°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: 89.6 early in the record → 128.5 recently. Frost days: 25 → 20.

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 2023, coldest in 1989: 107.9°F / −1.5°F.

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

Annual rainfall

~39.2 in/year on average. Last decade: +8% vs that average. Long-term trend: +0.71 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 Plano

Which is the warmest month in Plano?
On long-term average, the warmest month in Plano is August (mean daily temperature of about 83.9°F) and the coolest is January (about 43.9°F).
How does today's temperature in Plano compare to the historical average?
On October 20, 2026, Plano is forecast to reach a high of 78.6°F and a low of 53.1°F. The long-term average for this date (the full record since 1940) is a high of 77.1°F and a low of 55.8°F, so today's high is 1.5°F warmer than that average.
How much has Plano warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Plano is about 3.2°F warmer.
How much does it rain in Plano?
Plano receives about 39.2 inches of precipitation per year on long-term average, with May typically the wettest month.
What is the average temperature in Plano?
Over the full record (since 1940), the annual mean temperature in Plano is about 64.9°F. The warmest month is August and the coolest is January.
What are the average temperatures in Plano by month?
Average daily highs and lows for each month in Plano (°F, full record since 1940): January 55°/36°, February 59°/40°, March 67°/47°, April 75°/56°, May 82°/64°, June 89°/72°, July 93°/75°, August 94°/75°, September 87°/68°, October 78°/58°, November 66°/47°, December 58°/40°.
What is the weather like in Plano in summer?
In summer, June through August, Plano is hot. Afternoons run 89–94°F and nights 72–75°F; August is the warmest month. Rain eases through the season: 6 rainy days and 3.2 inches in June, 4 days and 1.9 inches in August.
What is the weather like in Plano in winter?
Winter in Plano (December to February) is cool. Expect 55–59°F by day and 36–40°F at night, with January the coldest month. Rain is steady at around 2.7 inches a month, spread over roughly 6 days.
What is the weather like in Plano in spring?
In spring, March through May, Plano is wet and pleasantly warm. March is still 67°F in the afternoon and 47°F at night, May already 82°F and 64°F. Rain picks up through the season: 8 rainy days and 3.8 inches in March, 9 days and 5.7 inches in May. No season is wetter.
What is the weather like in Plano in autumn?
September to November is autumn in Plano, and it is pleasantly warm. September still brings 87°F afternoons and 68°F nights, November only 66°F and 47°F. Rain is steady at around 3.3 inches a month, spread over roughly 6 days.
How many days a year does it rain in Plano?
On long-term average, Plano has about 74 days a year with at least 0.08 inches of rain or snow. The annual total is roughly 39.2 inches.

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