Climate and average weather in Blue Mountains
In Blue Mountains, the summers are warm, wet, and partly cloudy and the winters are cool and mostly clear.
Over the course of the year, the temperature in Blue Mountains typically varies from 3°C to 25°C, and is rarely below -1°C or above 33°C. January is the hottest month of the year, while July is the coldest.
Based on the travel score, the best times of year to visit Blue Mountains for warm-weather activities are from early January to mid May and early September to late December.
- Hottest
- Jan
- 25°
- Coldest
- Jul
- 3°
- Wettest
- Feb
- 146 mm
- Driest
- Jul
- 37 mm
- Rain / yr
- 994 mm
- 128 wet days
- Daylight
- 9.8–14.2 h
- shortest–longest
- Elevation
- 978 m
- 33.7°S
- Clearest
- Aug
- 40% cloud
Blue Mountains weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early January to mid May.
Temperature through the year
Daily average highs and lows in Blue Mountains, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 3.9 months, from November 19 to March 18, with daily high temperatures above 22°C. The hottest month of the year in Blue Mountains is January, with an average high of 25°C and low of 14°C.
The cool season lasts 3.2 months, from May 25 to August 28, with daily high temperatures below 15°C. The coldest month of the year in Blue Mountains is July, with an average low of 3°C and high of 12°C.
Days typically run about 11°C warmer than nights, with the widest day–night swing (around 12°C) in October.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 25 | 24 | 22 | 19 | 15 | 13 | 12 | 14 | 17 | 20 | 22 | 24 |
| Avg low (°C) | 14 | 14 | 12 | 8 | 6 | 4 | 3 | 3 | 5 | 8 | 10 | 12 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 25 | 14 |
| Feb | 24 | 14 |
| Mar | 22 | 12 |
| Apr | 19 | 8 |
| May | 15 | 6 |
| Jun | 13 | 4 |
| Jul | 12 | 3 |
| Aug | 14 | 3 |
| Sep | 17 | 5 |
| Oct | 20 | 8 |
| Nov | 22 | 10 |
| Dec | 24 | 12 |
How hot and cold Blue Mountains really feels
The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.
On the coldest nights, wind chill pulls the feels-like down to about -1°C (around August 5), with roughly 43 freezing days a year (feels-like at or below 0°C), worst in August.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 25 | 24 | 22 | 19 | 15 | 12 | 12 | 14 | 17 | 20 | 22 | 24 |
| Air high (°C) | 25 | 24 | 22 | 19 | 15 | 13 | 12 | 14 | 17 | 20 | 22 | 24 |
| Feels-like low (°C) | 14 | 14 | 12 | 7 | 3 | 1 | 0 | 0 | 3 | 6 | 9 | 12 |
| Air low (°C) | 14 | 14 | 12 | 8 | 6 | 4 | 3 | 3 | 5 | 8 | 10 | 12 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 25 | 25 | 14 | 14 |
| Feb | 24 | 24 | 14 | 14 |
| Mar | 22 | 22 | 12 | 12 |
| Apr | 19 | 19 | 7 | 8 |
| May | 15 | 15 | 3 | 6 |
| Jun | 12 | 13 | 1 | 4 |
| Jul | 12 | 12 | 0 | 3 |
| Aug | 14 | 14 | 0 | 3 |
| Sep | 17 | 17 | 3 | 5 |
| Oct | 20 | 20 | 6 | 8 |
| Nov | 22 | 22 | 9 | 10 |
| Dec | 24 | 24 | 12 | 12 |
Average hourly temperature in Blue Mountains
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on January afternoons, near 25°C, and coldest before dawn in July, near 3°C.
Blue Mountains weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 25° / 14° | 126 | 15.6 | 14 | 6.0 |
| Feb | 24° / 14° | 146 | 15.4 | 13.3 | 5.9 |
| Mar | 22° / 12° | 115 | 15.2 | 12.3 | 6.0 |
| Apr | 19° / 8° | 56 | 9.1 | 11.2 | 6.3 |
| May | 15° / 6° | 48 | 6.6 | 10.3 | 5.3 |
| Jun | 13° / 4° | 62 | 7.5 | 9.8 | 3.7 |
| Jul | 12° / 3° | 37 | 6.3 | 10 | 3.6 |
| Aug | 14° / 3° | 46 | 6.7 | 10.7 | 4.4 |
| Sep | 17° / 5° | 53 | 8.2 | 11.8 | 5.8 |
| Oct | 20° / 8° | 75 | 10.5 | 12.8 | 6.3 |
| Nov | 22° / 10° | 109 | 13.7 | 13.7 | 6.1 |
| Dec | 24° / 12° | 121 | 13.4 | 14.2 | 6.4 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Blue Mountains gets about 994 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.
The wetter season lasts 5.6 months, from around Oct 19 to Apr 6, peaking in February at about 55% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Aug 2.
February is the wettest month by volume, with 146 mm over about 15 wet days; July is the driest, with 37 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 50 | 54 | 48 | 31 | 22 | 24 | 21 | 22 | 27 | 34 | 45 | 45 |
| Rain days | 16 | 15 | 15 | 9 | 7 | 8 | 6 | 7 | 8 | 11 | 14 | 13 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 50 | 16 |
| Feb | 54 | 15 |
| Mar | 48 | 15 |
| Apr | 31 | 9 |
| May | 22 | 7 |
| Jun | 24 | 8 |
| Jul | 21 | 6 |
| Aug | 22 | 7 |
| Sep | 27 | 8 |
| Oct | 34 | 11 |
| Nov | 45 | 14 |
| Dec | 45 | 13 |
Monthly rainfall
Over a full year, Blue Mountains collects about 994 mm of rain across 128 wet days — roughly 83 mm in an average month.
It doesn’t fall evenly. February is the wettest month with 146 mm, while July is the driest at just 37 mm. The three wettest months alone bring about 40% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 126 | 146 | 115 | 56 | 48 | 62 | 37 | 46 | 53 | 75 | 109 | 121 |
| Rain days | 16 | 15 | 15 | 9 | 7 | 8 | 6 | 7 | 8 | 11 | 14 | 13 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 126 | 16 |
| Feb | 146 | 15 |
| Mar | 115 | 15 |
| Apr | 56 | 9 |
| May | 48 | 7 |
| Jun | 62 | 8 |
| Jul | 37 | 6 |
| Aug | 46 | 7 |
| Sep | 53 | 8 |
| Oct | 75 | 11 |
| Nov | 109 | 14 |
| Dec | 121 | 13 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Blue Mountains, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.
The clearer part of the year begins around June 18 and lasts for 4.1 months, ending around October 19. The clearest month is August, when the sky is clear, mostly clear, or partly cloudy 71% of the time on average.
The cloudier part of the year begins around October 20 and lasts for 5.8 months, ending around April 13. The cloudiest month is February, when it is overcast or mostly cloudy 53% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 49 | 47 | 50 | 56 | 59 | 57 | 67 | 71 | 67 | 57 | 47 | 48 |
| Cloudier (%) | 51 | 53 | 50 | 44 | 41 | 43 | 33 | 29 | 33 | 43 | 53 | 52 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 49 | 51 |
| Feb | 47 | 53 |
| Mar | 50 | 50 |
| Apr | 56 | 44 |
| May | 59 | 41 |
| Jun | 57 | 43 |
| Jul | 67 | 33 |
| Aug | 71 | 29 |
| Sep | 67 | 33 |
| Oct | 57 | 43 |
| Nov | 47 | 53 |
| Dec | 48 | 52 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around January 1, brings about 14 h 12 min of light; the shortest, around June 7, only 9 h 48 min — a swing of roughly 4 h 24 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 14.0 | 13.3 | 12.3 | 11.2 | 10.3 | 9.8 | 10.0 | 10.7 | 11.8 | 12.8 | 13.7 | 14.2 |
| Sunrise (AM) | 6:08 | 6:36 | 7:01 | 7:24 | 7:47 | 8:06 | 8:05 | 7:41 | 6:59 | 6:18 | 5:51 | 5:48 |
| Sunset (PM) | 8:08 | 7:51 | 7:16 | 6:34 | 6:03 | 5:52 | 6:03 | 6:25 | 6:47 | 7:09 | 7:37 | 8:02 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 14.0 | 6:08 | 8:08 |
| Feb | 13.3 | 6:36 | 7:51 |
| Mar | 12.3 | 7:01 | 7:16 |
| Apr | 11.2 | 7:24 | 6:34 |
| May | 10.3 | 7:47 | 6:03 |
| Jun | 9.8 | 8:06 | 5:52 |
| Jul | 10.0 | 8:05 | 6:03 |
| Aug | 10.7 | 7:41 | 6:25 |
| Sep | 11.8 | 6:59 | 6:47 |
| Oct | 12.8 | 6:18 | 7:09 |
| Nov | 13.7 | 5:51 | 7:37 |
| Dec | 14.2 | 5:48 | 8:02 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Blue Mountains averages about 12 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 8 and 17 days.
The sunnier stretch runs 4.0 months, from around Jun 16 to Oct 16. The sunniest month is August, with roughly 16 sunny days (bright).
The greyest month is November, down near 9 sunny days — about 44% fewer than the August peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 10 | 8 | 10 | 12 | 13 | 12 | 14 | 16 | 14 | 12 | 9 | 10 |
| Sky | Mixed | Mixed | Mixed | Mixed | Mixed | Mixed | Mixed | Bright | Mixed | Mixed | Mixed | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 10 | Mixed |
| Feb | 8 | Mixed |
| Mar | 10 | Mixed |
| Apr | 12 | Mixed |
| May | 13 | Mixed |
| Jun | 12 | Mixed |
| Jul | 14 | Mixed |
| Aug | 16 | Bright |
| Sep | 14 | Mixed |
| Oct | 12 | Mixed |
| Nov | 9 | Mixed |
| Dec | 10 | Mixed |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Blue Mountains, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 3.6 months, from around December 4 to March 23. The muggiest month is January, when the air feels humid, muggy or worse about 31% of the time.
The most comfortable stretch runs from around March 24 to December 3, and May is the most comfortable month — the air is dry or comfortable 100% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 34 | 32 | 55 | 90 | 99 | 100 | 100 | 100 | 100 | 96 | 81 | 60 |
| Comfortable (%) | 35 | 38 | 34 | 10 | 1 | 0 | 0 | 0 | 0 | 4 | 16 | 30 |
| Humid (%) | 28 | 26 | 10 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 10 |
| Muggy (%) | 3 | 3 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | |
|---|---|---|---|---|
| Jan | 34 | 35 | 28 | 3 |
| Feb | 32 | 38 | 26 | 3 |
| Mar | 55 | 34 | 10 | 1 |
| Apr | 90 | 10 | 1 | 0 |
| May | 99 | 1 | 0 | 0 |
| Jun | 100 | 0 | 0 | 0 |
| Jul | 100 | 0 | 0 | 0 |
| Aug | 100 | 0 | 0 | 0 |
| Sep | 100 | 0 | 0 | 0 |
| Oct | 96 | 4 | 0 | 0 |
| Nov | 81 | 16 | 3 | 0 |
| Dec | 60 | 30 | 10 | 0 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Blue Mountains is typically calm, near 9 km/h, and varies little with the seasons.
The windier part of the year lasts 5.3 months, from around May 29 to Nov 5. The windiest month is August, averaging about 12 km/h (calm).
The calmer part of the year runs from around Nov 6 to May 28, with March the calmest month at about 8 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 8 | 8 | 8 | 8 | 9 | 10 | 11 | 12 | 11 | 10 | 9 | 8 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 8 | calm |
| Feb | 8 | calm |
| Mar | 8 | calm |
| Apr | 8 | calm |
| May | 9 | calm |
| Jun | 10 | calm |
| Jul | 11 | calm |
| Aug | 12 | calm |
| Sep | 11 | calm |
| Oct | 10 | calm |
| Nov | 9 | calm |
| Dec | 8 | calm |
Hazard calendar for Blue Mountains
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Blue Mountains's rainy season runs October–March, when most of the year's rain falls.
Best time to visit Blue Mountains
To characterize how pleasant the weather is in Blue Mountains throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around mid January, Blue Mountains is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Blue Mountains for general outdoor tourist activities is from early September to mid May, with a peak score in the last week of September.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 6.0 | 5.9 | 6.0 | 6.3 | 5.2 | 3.7 | 3.6 | 4.4 | 5.8 | 6.3 | 6.1 | 6.4 |
| Rating | good | good | good | good | fair | fair | fair | fair | good | good | good | good |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 6.0 | good |
| Feb | 5.9 | good |
| Mar | 6.0 | good |
| Apr | 6.3 | good |
| May | 5.2 | fair |
| Jun | 3.7 | fair |
| Jul | 3.6 | fair |
| Aug | 4.4 | fair |
| Sep | 5.8 | good |
| Oct | 6.3 | good |
| Nov | 6.1 | good |
| Dec | 6.4 | good |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Blue Mountains for hot-weather activities is from late November to early March, with a peak score in the last week of December.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Blue Mountains, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
For a warm-season trip around January (highs near 25°C), the essentials are light clothes, rain gear and sun protection. In the cold season around July (highs near 12°C), pack a warm layer.
In January, Blue Mountains sees daytime highs around 25°C and nights near 14°C. Pack rain gear and sun protection. Worth having: light clothes. About 16 days see rain.
UV index (midday) in Blue Mountains by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Blue Mountains peaks around January 18 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 18 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 13 | 12 | 9 | 6 | 4 | 2 | 3 | 4 | 6 | 9 | 10 | 12 |
| Level | Extreme | Extreme | Very high | High | Moderate | Moderate | Moderate | Moderate | High | Very high | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 13 | Extreme |
| Feb | 12 | Extreme |
| Mar | 9 | Very high |
| Apr | 6 | High |
| May | 4 | Moderate |
| Jun | 2 | Moderate |
| Jul | 3 | Moderate |
| Aug | 4 | Moderate |
| Sep | 6 | High |
| Oct | 9 | Very high |
| Nov | 10 | Extreme |
| Dec | 12 | Extreme |
Average hourly UV index in Blue Mountains
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in January the burn window is concentrated in the middle of the day: about 9 hours a day reach index 3 (protection recommended), and 6.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 9 | 8.5 | 7 | 5.5 | 3 | 0 | 1.5 | 4 | 5.5 | 7.5 | 8.5 | 9 |
| UV ≥ 6 (h/day) | 6.5 | 6.5 | 4.5 | 1 | 0 | 0 | 0 | 0 | 0 | 4.5 | 6 | 6.5 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 9 | 6.5 |
| Feb | 8.5 | 6.5 |
| Mar | 7 | 4.5 |
| Apr | 5.5 | 1 |
| May | 3 | 0 |
| Jun | 0 | 0 |
| Jul | 1.5 | 0 |
| Aug | 4 | 0 |
| Sep | 5.5 | 0 |
| Oct | 7.5 | 4.5 |
| Nov | 8.5 | 6 |
| Dec | 9 | 6.5 |
Air quality in Blue Mountains by month
Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.
Air quality in Blue Mountains is worst in December — around 49 µg/m³ PM2.5 (poor), about 12.5× the cleanest month (July, 4 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 11 | 5 | 6 | 9 | 14 | 8 | 4 | 5 | 6 | 7 | 21 | 49 |
| Level | Good | Good | Good | Good | Moderate | Good | Good | Good | Good | Good | Moderate | Poor |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 11 | Good |
| Feb | 5 | Good |
| Mar | 6 | Good |
| Apr | 9 | Good |
| May | 14 | Moderate |
| Jun | 8 | Good |
| Jul | 4 | Good |
| Aug | 5 | Good |
| Sep | 6 | Good |
| Oct | 7 | Good |
| Nov | 21 | Moderate |
| Dec | 49 | Poor |
Growing season
Blue Mountains is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about August 29 to June 19 (295 days); outside that window a hard frost is an occasional risk.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 100 | 100 | 100 | 100 | 96 | 90 | 83 | 86 | 94 | 99 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 14 | 31 | 29 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 96 | 0 |
| Jun | 90 | 14 |
| Jul | 83 | 31 |
| Aug | 86 | 29 |
| Sep | 94 | 0 |
| Oct | 99 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Growing degree days
Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Blue Mountains banks about 1,464 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 299 | 252 | 214 | 111 | 19 | 0 | 0 | 0 | 32 | 110 | 176 | 251 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 299 |
| Feb | 252 |
| Mar | 214 |
| Apr | 111 |
| May | 19 |
| Jun | 0 |
| Jul | 0 |
| Aug | 0 |
| Sep | 32 |
| Oct | 110 |
| Nov | 176 |
| Dec | 251 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Blue Mountains receives about 4.7 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.4 and 6.9 kWh/m².
The brighter stretch of the year lasts 6.2 months, from around Sep 11 to Mar 17. The brightest month is December, averaging about 6.7 kWh/m² (intense).
The dimmest month is June, down near 2.5 kWh/m² — roughly 63% less than the December peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 6.5 | 5.5 | 4.7 | 3.8 | 3.0 | 2.4 | 2.8 | 3.7 | 4.9 | 5.8 | 6.2 | 6.6 |
| Level | Intense | Bright | Bright | Moderate | Moderate | Moderate | Moderate | Moderate | Bright | Bright | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 6.5 | Intense |
| Feb | 5.5 | Bright |
| Mar | 4.7 | Bright |
| Apr | 3.8 | Moderate |
| May | 3.0 | Moderate |
| Jun | 2.4 | Moderate |
| Jul | 2.8 | Moderate |
| Aug | 3.7 | Moderate |
| Sep | 4.9 | Bright |
| Oct | 5.8 | Bright |
| Nov | 6.2 | Intense |
| Dec | 6.6 | Intense |
Where is Blue Mountains?
Blue Mountains sits at 33.7°S, 150.3°E, 978 m above sea level, in Australia. The nearest listed city is Katoomba, 2.0 km away.
Topography around Blue Mountains
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Blue Mountains.
Within 3 km, the terrain around Blue Mountains has large variations in elevation — a maximum elevation change of 696 m around an average of 890 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,002 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,382 m.
The land around Blue Mountains is covered by trees (91%) within 3 km, trees (92%) within 16 km, and trees (73%) and grassland (21%) within 80 km.
Australia travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type I
- 230 V · 50 Hz
- Prices
- ≈ 90% of US
- price level, 2025
- GDP per capita
- $65,130
- 2025
- Happiness
- 6.9 / 10
- World Happiness, 2025
- Homicide rate
- 0.9
- per 100k, 2023
- Road deaths
- 4.9
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Blue Mountains (-33.7133°, 150.3306°, elevation 978 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).