Climate and monthly weather forecast
Pori, Finland

Embracing a geographical position in the south-western part of Finland, Pori exhibits a Humid Continental Climate under the Köppen climate classification. The term Dfb, designating this classification, depicts a climate with no dry season and with a warm summer. It's noteworthy that temperatures fluctuate between -8°C (17.6°F) in the coldest months to 21°C (69.8°F) in the warmest.

Over the year, there's no significant dry period. The rainfall in Pori goes from a low of 20mm (0.79") in April, with increases through the rest of the year up to a peak of 43mm (1.69") in August. This regular rain distribution indicates that Pori receives precipitation all year round.

While the sea temperatures range from a low of -0.2°C (31.6°F) in February and March to a high of 14.8°C (58.6°F) in August, daylight hours vary significantly between 5.6 hours in December to 19.3 hours in June. The lengths of day and night and the varying degree of warmth from the sun significantly influence the weather conditions throughout the year.

July proves to be the most favorable month to visit Pori due to optimal weather conditions. It's the time when the city experiences its highest temperatures, from 12°C (53.6°F) to 21°C (69.8°F). Coupled with the generous 18.4 hours of daylight, outdoor activities can be exploited to the maximum extent. Sea temperatures also reach a pleasant 14°C (57.2°F), perfect for those who fancy marine escapades.

If weather comfort is a determining factor, December through February may be least favorable for a visit. The mercury hovers between -9°C (15.8°F) to -3°C (26.6°F), becoming especially harsh for those unacclimated to freezing conditions. Daylight is scarce with a mere 5.6 to 9 hours in this period, providing limited scope for outdoor sightseeing.

Spring in Pori is relatively cool compared to other seasons. March witnesses temperatures from -5°C (23°F) to 1°C (33.8°F) and April further increases to -1°C (30.2°F) to 8°C (46.4°F). By May, temperatures begin to comfort the air with a high of 14°C (57.2°F) and a low of 4°C (39.2°F). Combined with relatively low precipitation from 20mm (0.79") to 24mm (0.94") during the spring months, it's an excellent time for landscape viewing.

Summers prove favorable for any vacationer in Pori. It's comfortably warm with temperatures varying between 9°C (48.2°F) and 21°C (69.8°F) from June to August. August also receives the highest rainfall at 43mm (1.69"), and this feat does not pose as a deterrent, considering the high temperature. Sea temperatures peak in this season to 14°C (57.2°F) enabling water-based activities.

A blend of chilly winds and cooling temperatures characterize autumn in Pori. Temperatures decrease gradually from 6°C (42.8°F) to -2°C (28.4°F) between September to November. Even though daylight shrinks to 7.2 hours in November, the bright hues of autumn leaves in the sunlight make this a season of pictorial charm.

The cold typically starts to set in from December, with temperatures plunging between -5°C (23°F) to -1°C (30.2°F). Freezing conditions persist till February with the mercury fluctuating from -9°C (15.8°F) to -3°C (26.6°F). Despite the chill, the winter landscape of Pori boasts a stark beauty, cloaked in snow, under the clear, cold winter sky. However, daylight is at its fewest, ranging from 5.6 hours to 9 hours, across the winter months.

This winter month shrouds Pori, Finland in long, frigid nights, with daylight making a brief, infrequent appearance. A steady plunge in temperatures characteristically earmarks the beginning of the year. Remarkably, the average high and low temperatures settle at -3°C (26.6°F) and -8°C (17.6°F) respectively, creating a chilling atmosphere. Weather in January »

The transition from January to February is marked by similar freezing conditions, lending continuity to the winter season. The average high and low temperatures continue at -3°C (26.6°F) and -9°C (15.8°F) respectively, reinforcing the city's winter status. Weather in February »

March offers a subtle shift from the intense freezing climate that previously dominated. Pori witnesses a bit of thawing as temperatures progress towards positivity, with the average high fluctuating around 1°C (33.8°F). However, the behavior of the weather still remains within the confines of winter. Weather in March »

April ushers in perceptible changes in Pori, signifying the much-awaited arrival of Spring. Unlike the preceding month, the average high and low temperatures climb to a relatively comfortable 8°C (46.4°F) and -1°C (30.2°F) respectively. Weather in April »

The weather transformation continues as May greets Pori with moderately warm days and cool nights. The city basks in an average high of 14°C (57.2°F), heralding the inception of summer. The month is characterized by nearly 17.6 hours of daylight, allowing more outdoor activities. Weather in May »

June marks the official initiation of the brief but appreciated Finnish summer. This is the period when daylight reigns supreme, extending up to approximately 19.3 hours in Pori. It is the peak of the city’s outdoor life, with various festivals and events scheduled under the cloudless skies. Weather in June »

Pori in July glorifies the summer season at its peak. The average high and low temperatures plateau at 21°C (69.8°F) and 12°C (53.6°F) respectively, producing the warmest month of the year. Residents and tourists alike revel in beach activities, picnics and long scenic drives. Weather in July »

August brings about subtle changes in Pori's weather dynamics as summer slowly starts to wind down. Nevertheless, the month continues to carry the charm of warm weather with the average high temperature touching 20°C (68°F). Finns make the most of the lingering summer enjoying outdoor concerts, coastal hangouts and boat tours. Weather in August »

September is a month of transition as autumn begins to cast its spell over Pori. As the average high temperature drops to around 14°C (57.2°F), the city begins to cool down. With the chilling winds picking up, leaves changing color, and the daylight hours reducing, signs of the impending winter become more discernible. Weather in September »

October in Pori unfolds a dramatic shift in weather patterns as the city fully immerses into autumn. The difference in temperature with September is clearly noticeable, with the average high chilling at around 8°C (46.4°F). The city's visual landscape transforms into a kaleidoscope of copper, gold, and brown tones. Weather in October »

November is the harbinger of the long Finnish winter in Pori. The temperature dives further, with the average high settling around 2°C (35.6°F), making the month considerably colder than October. The rapidly shortening daylight hours and frequent overcast skies set a wintry ambience. Weather in November »

Finally, Pori bids farewell to the year under a thick white blanket of snow. December is characterized by biting cold, with the average high temperature dipping to -1°C (30.2°F). With only around 5.6 hours of daylight, the city enters into the domain of the polar night. Weather in December »