Climate and monthly weather forecastIrvine, CA

Climate and monthly weather forecast
The climate of Irvine
Located in the heartland of California, Irvine features a predominant Csa climate, according to the Köppen climate classification, commonly referred to as a Mediterranean climate with hot summers. This geographical positioning renders unique weather patterns characterized by specific environmental factors typical for every season.Temperature variation manifests in a range from 50.5°F (10.3°C) to 79.9°F (26.6°C), a span that showcases Irvine's Mediterranean climate. January experiences a low of 50.5°F (10.3°C), climbing steadily to reach the hottest temperature of 79.9°F (26.6°C) by August. A gradual decrease in temperature succeeds this peak, rounding the year with a cooler 63°F (17.2°C) in December.
Rainfall distribution extends from a minor 0.08" (2mm) in June to a pronounced 1.54" (39mm) in December. This considerable variation reinforces the Mediterranean climate: extended dry summers followed by cool, wet winters. The majority of annual precipitation concentrates between November and March, while the period from June to September is remarkably drier.
The daily sunlight hours in Irvine start at 10 hours in January and incrementally rise to a high of 14.4 hours by June, subsequently declining towards the end of the year. Reflecting a Mediterranean environment, these patterns include long, sunny summers and shorter, mild winters.
The best time to visit Irvine
Visitors find Irvine's climate most welcoming between April and June. These months boast an impressive balance between moderately high temperatures, ranging from 66°F (18.9°C) to 73.6°F (23.1°C), and minimally low rainfall amounts, dropping to 0.55" (14mm) in April and falling further to just 0.08" (2mm) in June. Coinciding with this favorable weather is an increase in daily sunshine hours, reaching a high of 14.4 hours per day in June, making it an ideal time for outdoor activities.The worst time to visit Irvine
The less attractive time to visit Irvine for those unsuited to colder and wetter conditions fall between November and February. The temperatures during these months drop to a yearly low between 63°F (17.2°C) and 64°F (17.8°C). Accompanying these colder temperatures is an increase in precipitation, reaching a peak of 1.54" (39mm) in December and 1.18" (30mm) in February.Spring weather in Irvine
The weather transition from winter to summer during March through May materializes as spring in Irvine. Average temperatures start at 66°F (18.9°C) in March and advance to 69.8°F (21°C) in May. However, the rainfall depicts a declining trend, receding from 0.87" (22mm) in March to a mere 0.31" (8mm) by the end of spring. An abundance of sunshine is customary for springtime, with sunlight exposure reaching up-to 11.1 hours daily in May.Summer weather in Irvine
Summer in Irvine, extending from June to August, is embodied by warm temperatures and scarce rainfall. Temperatures average a high of 73.6°F (23.1°C) in June and peak at 79.9°F (26.6°C) in August. Rainfall is virtually absent during the summer, only reaching 0.43" (11mm) in July. The day's length is also at its zenith, with daylight lasting for 14.1 to 14.4 hours.Autumn weather in Irvine
Autumn in Irvine unfolds from September to November. During this period, temperatures fall from a high of 79°F (26.1°C) in September to a lower 69.6°F (20.9°C) in November. In conjunction with the chilling trend, there is a gradual increase in rainfall, climbing from 0.31" (8mm) in September to 0.75" (19mm) in November. Despite the reduced temperatures, Irvine remains relatively sunny during autumn with 10.6 sunshine hours daily in November.Winter weather in Irvine
December to February depicts winter in Irvine, featuring cold temperatures and relatively higher rainfall. The temperatures drop to 63°F (17.2°C) by December and fluctuate marginally throughout winter. Rainfall reaches its maximum of 1.54" (39mm) in December and maintains a high average throughout winter. Even during these winter months, sunshine hours rank moderately high, with 10 hours in December and January, indicating frequent bright and sunny days.Weather in January
In contrast to much of the United States during this time, January in Irvine, California is strikingly mild. Temperatures are comfortable, and it is not uncommon to see residents walking around in light sweaters or jackets. The primary force at work during this month is rain, coming down at an average of 1.14" (29mm) as compared to a dryer February. Weather in January »Weather in February
February in Irvine exhibits slight warming in comparison to January, with temperatures gradually creeping upwards. This increment usually indicates a transition away from the colder winter and towards the upcoming warmth of spring. Weather in February »Weather in March
March sees both longer daylight hours and an increase in sunshine hours. The climate continues to shift from cool to warm in this vibrant city. The upward trend in temperature from February to March makes outdoor activities more appealing, with residents often spending more time outside. Weather in March »Weather in April
Being in the heart of spring, the city of Irvine in April bathes in temperatures that sees daily highs up to 68.4°F (20.2°C). The most striking aspect of April’s ambiance is the significant decrease in rainfall from March, recording a mere 0.55" (14mm). Weather in April »Weather in May
May in Irvine signals the onset of summer with temperatures consistently on rise. Stepping into the warmer months, this city exhibits less rainfall, giving ample sunshine to the urban dweller. The decrease in average rainfall from April to May of 0.31" (8mm) makes room for more outdoor endeavors. Weather in May »Weather in June
As summer hits its stride, June in Irvine experiences an increase in the average temperature while rainfall is at its lowest of 0.08" (2mm). The cooler evenings provide a perfect counterbalance to the warm daytime weather. The city is usually bustling with summer events, including numerous outdoor fairs and festivals. Weather in June »Weather in July
July is the warmest month in Irvine, with an average high temperature that peaks at 77.9°F (25.5°C). In spite of such high temperatures, the city avoids oppressive heat because of its signature coastal breeze. This is also the heart of summer in Irvine, thus making it a hotspot for outdoor events such as carnivals, food festivals, and open-air concerts. Weather in July »Weather in August
August in Irvine is characterized by high temperatures, similar to its predecessor in July. However, the shift towards the end of summer starts taking place towards the latter half of the month. The rainfall figure of 0.35" (9mm) indicates the pacifying heat while keeping it an excellent month for outdoor fun. Weather in August »Weather in September
Irvine in September reveals a shift from the summer to the fall season. However, the temperature remains warm, enabling outdoor activities to persist. The slight cooling is indicative of the approach of autumn but without any significant reduction in sunshine, keeping the city's atmosphere vibrant. Weather in September »Weather in October
As the heat of summer completely subsides, October in Irvine greets residents and visitors with milder temperatures and a notable surge in rainfall compared to the drier September. The atmosphere in October is typically characterized by a slight chill and shorter daylight hours. Weather in October »Weather in November
November entails the sharp transition from autumn to winter in Irvine. As the temperature continues to drop, the weather calls for warmer clothing and a switch to indoor activities. Contrasting with the trend from October to November, the average rainfall increases to 0.75" (19mm), setting in the rainy season vibe. Weather in November »Weather in December
Ending the cycle of seasons in Irvine, December is synonymous with cooler temperatures and the holiday season. Despite the drop in temperatures, the conditions remain relatively mild compared to other regions of the country. December brings the highest amount of rainfall for the year, with an average precipitation of 1.54" (39mm). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Irvine, CA
The warmest month (with the highest average high temperature) is August (79.9°F).
The month with the lowest average high temperature is December (63°F).
The month with the highest average low temperature is August (64.9°F).
The coldest month (with the lowest average low temperature) is February (50.5°F).
Average pressure
Irvine, CA
- Average pressure in January:
30.1"Hg - Average pressure in February:
30.05"Hg - Average pressure in March:
30.03"Hg - Average pressure in April:
29.96"Hg - Average pressure in May:
29.93"Hg - Average pressure in June:
29.88"Hg
- Average pressure in July:
29.91"Hg - Average pressure in August:
29.9"Hg - Average pressure in September:
29.89"Hg - Average pressure in October:
29.94"Hg - Average pressure in November:
30.03"Hg - Average pressure in December:
30.07"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed
Irvine, CA
- Average wind speed in January:
5.2mph - Average wind speed in February:
5.4mph - Average wind speed in March:
5.6mph - Average wind speed in April:
6.2mph - Average wind speed in May:
6mph - Average wind speed in June:
5.3mph
- Average wind speed in July:
5.2mph - Average wind speed in August:
4.9mph - Average wind speed in September:
4.8mph - Average wind speed in October:
4.8mph - Average wind speed in November:
5.2mph - Average wind speed in December:
5.3mph
The windiest month (with the highest average wind speed) is April (6.2mph).
The calmest months (with the lowest average wind speed) are September and October (4.8mph).
Average humidity
Irvine, CA
The month with the highest relative humidity is June (71%).
The month with the lowest relative humidity is November (56%).
Average rainfall
Irvine, CA
- Average rainfall in January:
1.14" - Average rainfall in February:
1.18" - Average rainfall in March:
0.87" - Average rainfall in April:
0.55" - Average rainfall in May:
0.31" - Average rainfall in June:
0.08"
- Average rainfall in July:
0.43" - Average rainfall in August:
0.35" - Average rainfall in September:
0.31" - Average rainfall in October:
0.39" - Average rainfall in November:
0.75" - Average rainfall in December:
1.54"
The wettest month (with the highest rainfall) is December (1.54").
The driest month (with the least rainfall) is June (0.08").
Average rainfall days
Irvine, CA
- Average rainfall days in January:
5.4 days - Average rainfall days in February:
6.7 days - Average rainfall days in March:
7.9 days - Average rainfall days in April:
6.8 days - Average rainfall days in May:
5.4 days - Average rainfall days in June:
2.2 days
- Average rainfall days in July:
5 days - Average rainfall days in August:
3.3 days - Average rainfall days in September:
4.1 days - Average rainfall days in October:
5.1 days - Average rainfall days in November:
4.9 days - Average rainfall days in December:
6.9 days
The month with the highest number of rainy days is March (7.9 days).
The month with the least rainy days is June (2.2 days).
Average daylight / Average sunshine
Irvine, CA
- Average daylight in January:
10h and 12min - Average daylight in February:
11h and 0min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 0min - Average daylight in May:
13h and 54min - Average daylight in June:
14h and 24min
- Average daylight in July:
14h and 6min - Average daylight in August:
13h and 24min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 18min - Average daylight in November:
10h and 24min - Average daylight in December:
10h and 0min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in January:
6h and 48min - Average sunshine in February:
6h and 48min - Average sunshine in March:
8h and 42min - Average sunshine in April:
10h and 54min - Average sunshine in May:
11h and 6min - Average sunshine in June:
11h and 48min
- Average sunshine in July:
12h and 0min - Average sunshine in August:
12h and 0min - Average sunshine in September:
10h and 36min - Average sunshine in October:
8h and 30min - Average sunshine in November:
7h and 6min - Average sunshine in December:
6h and 36min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days
Irvine, CA
- Average sunshine days in January:
24.5 days - Average sunshine days in February:
19.8 days - Average sunshine days in March:
21.3 days - Average sunshine days in April:
21.1 days - Average sunshine days in May:
19.7 days - Average sunshine days in June:
22.3 days
- Average sunshine days in July:
22.7 days - Average sunshine days in August:
23.9 days - Average sunshine days in September:
22.1 days - Average sunshine days in October:
23.3 days - Average sunshine days in November:
23.4 days - Average sunshine days in December:
22.5 days
The month with the most sunshine days is January (24.5 days).
The month with the least sunshine days is May (19.7 days).
Average UV index
Irvine, CA
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 4).
Average cloud cover
Irvine, CA
The month with the most cloud cover is December (Cloud cover 24).
The month with the least cloud cover is August (Cloud cover 7).
Average visibility
Irvine, CA
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





