Lahti climate
Lahti (Finland) has a warm-summer humid continental climate (Köppen Dfb). The average temperature over the year is 4 °C40 °F, and about 746 mm29 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Lahti climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | −522 | −1113 | −817 | 522.1 | 30 |
| Feb | −523 | −1113 | −818 | 421.6 | 28 |
| Mar | 032 | −720 | −426 | 411.6 | 30 |
| Apr | 846 | −131 | 438 | 441.7 | 18 |
| May | 1559 | 542 | 1050 | 602.3 | 3 |
| Jun | 1966 | 1050 | 1458 | 863.4 | 0 |
| Jul | 2272 | 1356 | 1864 | 853.4 | 0 |
| Aug | 2068 | 1253 | 1661 | 722.9 | 0 |
| Sep | 1558 | 745 | 1152 | 642.5 | 0 |
| Oct | 744 | 235 | 440 | 722.9 | 11 |
| Nov | 134 | −228 | −131 | 652.6 | 19 |
| Dec | −327 | −719 | −523 | 632.5 | 27 |
| Year | 2272 | −1113 | 440 | 74629 | 165 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 98% | 82% | 0.3 | 6:24 |
| Feb | 99% | 79% | 0.8 | 8:54 |
| Mar | 95% | 69% | 2.2 | 11:33 |
| Apr | 83% | 67% | 3.8 | 14:34 |
| May | 77% | 62% | 5.2 | 17:21 |
| Jun | 77% | 66% | 5.4 | 19:12 |
| Jul | 79% | 64% | 5.2 | 18:24 |
| Aug | 81% | 63% | 4.0 | 15:46 |
| Sep | 87% | 67% | 2.4 | 12:46 |
| Oct | 92% | 78% | 1.1 | 9:53 |
| Nov | 97% | 85% | 0.3 | 7:09 |
| Dec | 98% | 84% | 0.1 | 5:35 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Lahti is like
The warmest month is July, with an average high of 22 °C72 °F and a low of 13 °C56 °F. The coldest is January, when highs average −5 °C22 °F and lows −11 °C13 °F. Seasons are strongly marked: the warmest month is on average 25.8 °C46.5 °F warmer than the coldest.
Annual precipitation is moderate at about 746 mm29 in. The wettest three-month stretch is June–August, which brings 33% of the annual total. The wettest month is June (86 mm3.4 in), the driest is March (41 mm1.6 in).
Relative humidity ranges from 77% in June to 99% in February. The clearest skies (lowest average cloud amount, 62%) are typical of May. Average wind speed near the ground ranges from 2 km/h (1 mph) in November to 3 km/h (2 mph) in April. Daylight lasts from about 5.6 hours in December to 19.2 hours in June.
A lasting snow cover is typical in November–March, when the average snow depth in the reanalysis exceeds 10 cm (deepest in February, about 26 cm).
Best time to visit Lahti
Based on these averages, the most comfortable months for sightseeing and outdoor activities are July and August: average highs of 20 °C68 °F to 22 °C72 °F with 72 mm2.9 in to 85 mm3.4 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of −5 °C22 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Lahti
- Winter (December–February) — highs −522 to −3 °C27 °F, lows −1113 to −7 °C19 °F, about 52 mm2.1 in of precipitation a month. Pack a winter coat, hat, gloves and warm, non-slip boots.
- Spring (March–May) — highs 032 to 15 °C59 °F, lows −720 to 5 °C42 °F, about 48 mm1.9 in of precipitation a month. Pack a warm coat, layers and closed shoes and shoes with good grip, as frost is common.
- Summer (June–August) — highs 1966 to 22 °C72 °F, lows 1050 to 13 °C56 °F, about 81 mm3.2 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket.
- Autumn (September–November) — highs 134 to 15 °C58 °F, lows −228 to 7 °C45 °F, about 67 mm2.6 in of precipitation a month. Pack a warm coat, layers and closed shoes.
How Lahti compares
Compared with Vantaa, about 84 km to the southwest, Lahti is on average 1 °C1.8 °F cooler and receives a similar amount of precipitation. The difference is largest in January (2.3 °C4.2 °F cooler).
Of the 9 places in Finland covered by World Climates, Lahti is the 5th warmest by annual mean temperature and the 4th wettest by annual precipitation. See all of them on the Finland climate page.
Places in other countries with the most similar temperature and rainfall pattern: Saint Petersburg (Russia, Dfb), Velikiy Novgorod (Russia, Dfb) and Pskov (Russia, Dfb).
Nearby places
- Vantaa 84 km · 5 °C42 °F · 733 mm29 in
- Helsinki 99 km · 6 °C43 °F · 712 mm28 in
- Espoo 103 km · 6 °C43 °F · 727 mm29 in
- Tampere 116 km · 4 °C40 °F · 776 mm31 in
- Jyväskylä 140 km · 4 °C39 °F · 807 mm32 in
- Tallinn 179 km · 6 °C43 °F · 685 mm27 in
- Turku 194 km · 6 °C42 °F · 723 mm28 in
- Kuopio 237 km · 3 °C37 °F · 883 mm35 in
Frequently asked questions
What is the warmest month in Lahti?
July is the warmest month in Lahti, with an average high of 22 °C (72 °F) and an average low of 13 °C (56 °F).
What is the coldest month in Lahti?
January is the coldest month, with an average high of -5 °C (22 °F) and an average low of -11 °C (13 °F).
When does it rain the most in Lahti?
June is the wettest month with about 86 mm (3.4 in) of precipitation; March is the driest with about 41 mm (1.6 in).
What is the best time to visit Lahti?
Judging by long-term averages, the most comfortable months are July and August.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.