The climate of Phoenix
Phoenix, part of the Sonoran Desert, lies in the subtropical desert climate or BWh according to the Köppen climate classification. This environment is characterized by extremely hot summers, mild winters, and scant rain.
Consistently warm temperatures prevail throughout the year, with highs ranging from a relatively mild 64.2°F (17.9°C) in
January to a sweltering 103.6°F (39.8°C) in
July. Corresponding lows range from 47.5°F (8.6°C) in January to 84.7°F (29.3°C) in
August—indicating no month is devoid of warmth.
Rainfall in Phoenix is rather infrequent with the densest precipitation occurring in the warmer months of July to
September—with values amounting to 0.75" (19mm), 0.59" (15mm), and 0.67" (17mm) respectively. During the rest of the year, the city experiences lighter precipitation generally not surpassing half an inch.
Unique to Phoenix is the minimal snowfall it experiences throughout the year, with the only recorded snow in
November at a minimal 0.04" (1mm)—rare for many but typical in Phoenix's desert topography. Additionally, the city is illuminated generously during the year, earning between 10 to 14.3 hours of daylight, coupled with a high UV index that peaks between
May and August at an 8.
The best time to visit Phoenix
When to visit
Phoenix largely depends on heat tolerance and the desired activities.
November through
April is the city’s peak season due to mild and pleasant temperatures. During this time, temperatures range from highs of 64.2°F (17.9°C) to 90.9°F (32.7°C) and lows of 47.5°F (8.6°C) to 67.6°F (19.8°C)—an ideal climate for outdoor exploration or lounging by the pool without being overwhelmed by summer's ferocious heat.
Moreover, these months boast moderate humidity (between 33% to 43%), lower UV index (between 3 and 6), and longer sunshine hours (varying between 7.1 and 11.9 hours), making them the most favorable for visitors.
The worst time to visit Phoenix
Despite
Phoenix's attractive year-round warmth, the months of
June to
September can be excessively hot for most people. During these months, average high temperatures soar beyond 100°F (37.8°C). Wind speed slightly increases during this season (from 5.9mph (9.5km/h) to 6.4mph (10.3km/h)), but this does little to mitigate the intense heat.
Additionally, humidity drops to its lowest between 16% to 19%, and a higher UV index of 8 potentially raises the risk of sunburn or heatstroke if proper precautions are not taken. Therefore, unless seeking the full desert heat experience, these months are perhaps best avoided.
Spring weather in Phoenix
During
March to
May,
Phoenix begins its transition from mild to hot weather. Temperatures gradually escalate with average highs jumping from 76.1°F (24.5°C) in March to 90.9°F (32.7°C) in May. Corresponding lows also rise from 55.9°F (13.3°C) to 67.6°F (19.8°C).
This season records little rainfall, with the driest month being May registering just 0.08" (2mm). Moreover, daylight hours increase (from 12 to 13.9 hours) along with the UV index, starting at 5 in March and reaching 8 in May.
Summer weather in Phoenix
Summer is intimidating in
Phoenix, with
June to
September featuring the year's hottest temperatures. Daytime highs in these months easily surpass 100°F (37.8°C), and nighttime lows rarely drop below the mid-70s°F.
The summer months also yield the highest rainfall of the year, with
July's 0.75" (19mm) being the peak. However, even at its highest, rainfall remains quite minimal. This season also experiences the highest UV index of 8.
Autumn weather in Phoenix
Autumnal temperatures bring some respite from the summer heat, with averages receding gradually from
September to
November. Highs dip from 96.3°F (35.7°C) to 73.6°F (23.1°C) and lows from 78.8°F (26°C) to 56.3°F (13.5°C).
Rainfall during this period is slightly lower than summer, but it still maintains a consistent presence, reaching its pinnacle in September at 0.67" (17mm). UV index begins to decrease, registering a 7 in September and dropping to 4 by November.
Winter weather in Phoenix
Phoenix embraces winter in a unique way, with temperatures staying comfortably warm compared to most regions.
December to
February features highs in the 60s°F and lows in the 40s°F and 50s°F—quite mild for a typical winter.
These cooler months bring a marginally higher chance of rain, with December and February both registering 0.59" (15mm). However, the overall climatic conditions remain predominantly dry, showing Phoenix's consistent adherence to its desert climate categorization.
Weather in January
Phoenix,
Arizona, ushers in the new year with mild winter conditions, making outdoor activities rather pleasant.
January weather exhibits a stark contrast to the sizzling summer months the city is known for. Reaching to a mild 64.2°F (17.9°C), the city enjoys its second-lowest average high temperature.
Weather in January » Weather in February
Bidding adieu to
January’s cool tones,
February in
Phoenix brings marginally warmer temperatures. This transitional weather marks the start of moderate spring conditions. The average high temperature leaps to 67.6°F (19.8°C), slightly warmer compared to the previous month.
Weather in February »Weather in March
March witnesses a continued gradual increase in temperature as
Phoenix moves further into spring. This month exposes Phoenix's desert characteristics with climbing temperatures and falling humidity levels. The city welcomes the warmer 76.1°F (24.5°C) average high temperature, providing bounteous warmth without the intense heat of summer.
Weather in March »
Weather in April
April in
Phoenix,
Arizona, encapsulates the end of spring, paving the way for the fast-approaching summer. The city experiences a noteworthy jump in temperatures, signaling the start of stark sunny weather. Soaring to 83.1°F (28.4°C), it sets the stage for the high temperatures that define Phoenix's weather.
Weather in April » Weather in May
May stands as the threshold to the sweltering summer that
Phoenix is famous for. As the city transitions into the hotter part of the year, the dry and sunny weather becomes prominent. The temperature index hits 90.9°F (32.7°C), indicating an impending scorching summer.
Weather in May » Weather in June
In
June,
Phoenix fully embraces its notoriously torrid summer weather. The city hits triple-digit temperatures, characterized by sunny days and almost no rain. Predominantly dry, the temperature reaches an average high of 102°F (38.9°C), making June one of the hottest months of the year.
Weather in June »
Weather in July
July in
Phoenix prevails as the pinnacle of the city's hot, arid summer. The city swims in extremely high temperatures and sun-drunk days. Topping at 103.6°F (39.8°C), it holds the record for the highest average high of the year. An inevitable increase in rainfall provides the first sign of respite from the unforgiving dry spell.
Weather in July » Weather in August
August in
Phoenix continues to be dominated by the summer heat, though slight hints of a reprieve become apparent. It segments in the last phase of the intense summer punctuated by occasional thunderstorms. Marginally lower than
July, the average high temperature hangs around 102.6°F (39.2°C).
Weather in August » Weather in September
The arrival of
September in
Phoenix marks the outset of milder temperatures and reduced humidity. The city starts to witness a notable drop in temperatures, signaling the retreat of the sweltering summer with a distinct autumn breeze.
Weather in September »
Weather in October
October in
Phoenix is distinguished by diversely agreeable weather, marking the city's transition into vibrant autumn. The heat of summer is exchanged for the milder, cooler temperature spectrum. Compared to
September, the city sees a significant drop in the average high temperature, sliding down to 85.1°F (29.5°C).
Weather in October » Weather in November
As fall permeates
Phoenix in
November, the city takes pleasure in the mild and enjoyable weather it offers. A significant shift in temperature accompanies the departure of
October. The temperature takes another drop, reaching a pleasant average high of 73.6°F (23.1°C).
Weather in November »Weather in December
December in
Phoenix rounds off the year under the gentle glow of winter sun. As the city greets the last month of the year, a soothing chill fills the air. Average high temperatures drop even further to a bearable 63°F (17.2°C), confirming the onset of winter.
Weather in December »