A series of low pressure systems have brought a month's-worth of rain in one place, strong winds, thunderstorms, unusually large hailstones and even waterspouts just in the past few days, though often these events are quite localized.

Experts say a warming climate could make some of these phenomena more intense, while long-term, Estonia's topography, its maritime location and its latitude continue to be dominant factors.

The Environment Agency (Keskkonnaagentuur) characterized the weather over the weekend and through to the start of this week as "unsettled," with thunderstorms, heavy rain, hail and strong gusts of wind. For instance on the evening of Friday, July 3, hailstones measuring up to 4.5 centimeters in diameter fell over Keila, southwest of Tallinn; two nights later, close to 95 millimeters of rain was recorded within six hours in the eastern portion of the island of Muhu, while unconfirmed data suggests total rainfall over the course of 24 hours at over 100 millimeters – roughly the usual national average for July as a whole.

Those heavy downpours caused localized flooding, and funnel clouds and waterspouts have been observed in several parts of the country too.

Late on July 6 and overnight into July 7, thunderstorms again brought torrential rain, hail in places and wind gusts of up to 23 meters per second to western and northwestern Estonia. The Environment Agency expects the unsettled weather to continue in the coming days, with more rain and thunderstorms on the way.

Piia Post, professor of climate science at the University of Tartu, noted summer in Estonia, as at other times of the year, is in any case often characterized by changeable weather conditions.

,"An Estonian summer alternates between hot and dry, and cool and rainy," she said, adding that similarly wet summers to those seen recently had been common from the late 1970s through the 1990s.

This is the result of a generally warmer climate, she said, which serves to accelerate the atmosphere's water cycle, bringing more moisture into the air as water vapor. This subsequently condenses into cloud and, often, rain, and with the outcome that precipitation events can get more intense.

Paradoxically the warmer conditions can lead to drier periods too: Higher temperatures boost evaporation and so also lead to more drought periods, Post said.

Summer rainfall can vary greatly by location

Külli Loodla, senior specialist with the Environment Agency, noted summer showers in Estonia are often highly localized. This means that rainfall totals can differ significantly, even between places which are short distances apart. This variation is influenced by convection currents, which mean the cooling effect of the Baltic Sea keep coastal areas and islands cooler during summer and reduces the formation of strong convective storms. While Estonia is a relatively low lying country, there are variations in relief, and the higher terrain, mostly in the interior and particularly in the South, typically gets more precipitation than surrounding, lower areas.

"In one place, tens of millimeters of rain may fall within an hour, while just a few kilometers away it may not rain at all," Loodla added.

Weather patterns affect urban and rural areas alike

Post said the changing weather patterns are already affecting both agricultural areas and the towns in Estonia. For instance the milder winters and more widely varying precipitation have led to an increase in the cultivation of winter cereals. Traditional haymaking, which necessarily requires dry conditions, has on the other hand largely been replaced by silage production.

In the cities, flood risks are heightened not only by heavier downpours but also by the extensive modern day asphalt and concrete surfaces, which can hamper water drainage into the ground.

Planning issues and oversights also play their part, Post said. "Land is divided between multiple owners, and planning is often carried out only on an individual plot basis, without considering that water does not 'recognize' property boundaries. It always flows downhill, and collects together in the 'bowls'."

Average annual precipitation has increased somewhat over recent decades, Post noted, again linked to a warming climate, since warmer air can hold more moisture. Much of the overall rise in precipitation has been seen during the milder winters experienced in recent years, while for the other seasons, the rise has mainly been the result of more intense individual rainfall events.

What is in store for the rest of this summer in Estonia?

As for the rest of the current summer, it is unlikely to be a vintage one but next month may bring a "proper" season.

The Environment Agency's chief meteorologist, Taimi Paljak, the rest of July's weather, with over three weeks to go, is likely to remain unsettled. From the weekend, temperatures may briefly rise to around 25C for a few days, before dropping back to around the 20C-mark during the second half of the month. Bands of rain will also be periodically moving across the country during that time.

August is forecast to be warmer than average and may bring a two-week spell of hot, dry weather, although the exact timing of this remains uncertain at this stage.

European heatwave will not reach Estonia

The recent major heatwave seen in Western Europe which hit the headlines did not reach Estonia and the surrounding region.

The episode was the result of a large, persistent high-pressure system stretching all the way from the Mediterranean across much of Western Europe, including France and parts of the U.K. The reason it never reached Estonia is that atmospheric processes have a typical spatial scale, beyond which they cannot expand intact, Post noted. The system did influence Estonia's weather somewhat, but only during its dying days. "The high-pressure system only began to influence Estonia after it had moved eastward, but by then it was already breaking down," Post said.

As for the next 24 hours, it seems like business as usual since not only is rain forecast, but a nationwide heavy rain warning has been issued. The temperature high on Wednesday is just 17C, and while it will get gradually warmer towards and during the weekend, the rain and thunderstorms are set to continue.

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