With the spring equinox taking place on Monday, March 20, AccuWeather’s expert team of international forecasters has released the details of what the upcoming spring season will hold in Europe.
On March 9, NOAA’s Climate Prediction Center officially declared that the El Niño-Southern Oscillation phase has transitioned from La Niña to neutral, meaning neither El Niño nor La Niña is underway. This neutral phase is expected to persist through the end of spring into early summer and play a role in influencing global weather patterns, transitioning to El Niño sometime during the summer months.
AccuWeather meteorologists have incorporated this factor when developing the European spring forecast and say that the prevailing weather patterns across Europe from the end of March into the start of June will feature residually cold air across northern Europe early, mild conditions in the eastern regions, a dominant storm track across the south at times and an early ignition of severe weather for some spots.
Although springtime is generally associated with a leap toward warmer days, March, as observed already, can still bring bouts of wintry weather including impactful snowfall events. Portions of the United Kingdom, Scandinavia and the Alpine region are likely to end the month of March with anomalously higher snowfall totals, while many other parts of the continent will trend near to below the historical average.
A weather phenomenon called a sudden stratospheric warming event has played a large role in forcing cold conditions across much of northern Europe during the first half of March. Every few years, this event is triggered by a disruption in the upper levels of the Earth’s atmosphere, where the polar vortex resides.
The polar vortex is a band of cold, strong westerly winds circulating around Earth’s polar regions. At times, the bands can temporarily weaken, resulting in the cold air previously contained by the vortex descending very quickly from the stratosphere to the surface. As the disruption occurs, however, it causes stratospheric temperature levels to rise rapidly, hence the phenomenon’s namesake.
These sudden stratospheric warming events are responsible for what brought the famous ‘Beast from the East’ to the United Kingdom and Ireland from late February to March 2018.
Flakes fluttered across London during the second week of March, while heavy and disruptive accumulations of snow were observed in the Midlands, Wales and portions of Scotland. During the first half of the month, temperature departures from the historical average for this time of year trended between 0.5 and 2.5 degrees below zero Fahrenheit for major cities such as Edinburgh, Scotland; London, England; Paris, France; and Berlin, Germany.
However, the chilly conditions and active pattern that developed across northern Europe in early March will eventually transition to milder, tranquil weather sometime during early spring.
Temperatures across the U.K. are expected to trend closer to the historical average into late April, but AccuWeather forecasters say that this transition might not come as a smooth, gradual increase to warmer days.
“The United Kingdom and Ireland may feature a roller coaster of temperatures through the end of April but may end up balancing out to near the monthly historical average,” explained AccuWeather Senior Meteorologist Tyler Roys.
Temperatures may trend above the historical average for a stretch of time across England, Wales, Northern Ireland and parts of Scotland; however, waves of frontal passages can disrupt the springtime warming trend and drop conditions to slightly below average for a time. This turbulent temperature pattern may even out the monthly trend to near the historical average overall for April.
The risk of frost or freeze is expected to linger into mid-April across parts of the United Kingdom, stretching as far south as the Midlands. Snowfall chances that push into spring will likely be isolated to the higher terrain across Scotland, England and Wales, while the lowlands will face a lower threat of springtime wintry showers as temperatures begin to moderate.
Overall, precipitation values across the U.K. may trend near to slightly above the historical average during April and May. In a typical year, the driest months for London include the stretch from February to May, when average values for each month often range between 1.3 and 1.5 inches (33 and 38 mm (0.12 feets)) in the city.
In a typical year, the United Kingdom windstorm season is considered to last from October through the end of March.
So far, for the 2022-2023 season, the UK Met Office has named one windstorm in mid-February, designated Storm Otto. By mid-March of the previous 2021-2022 season, the UK Met Office had already named six windstorms, indicating that the 2022-2023 windstorm season will likely conclude as much less active in comparison to last year.
The primary storm track across southern Europe in March could spell trouble for water levels and drought across the United Kingdom, Ireland and even parts of France. Already this year, many regions have observed anomalously dry conditions, igniting concern for future water levels for not only residents but also the environment.
There was a remarkable lack of rain across the United Kingdom in February. Provisional observations from the UK Met Office indicated that England observed its driest February in 30 years. London recorded only 8% of its typical rainfall in February, while observations from Birmingham, England, totaled only 16% of the historical average rainfall for February.
According to Météo France, a stretch of 32 consecutive days without measurable rainfall (less than 1 mm of rain daily) was observed from Jan. 20, 2023, to Feb. 21, 2023. This set a new record for the longest consecutive stretch of days without measurable rainfall since 1959. Another notable stretch was back in 2020 from March 17 to April 16, when there were 31 consecutive days without measurable rainfall recorded.
On the flip side, a dominant storm track into southwestern Europe and a projected increase in springtime precipitation across southern and south-central regions are raising concerns among forecasters for a flood threat in locations such as Italy and the Balkans.
“Given how warm the Mediterranean is, storms could provide additional moisture and lead to an increase in flood threats. This is particularly a concern for the western slopes of the Apennines and the Dinaric Alps,” explained Roys.
Springtime showers and rainfall may be welcomed across the Alpine region to help replenish the reservoirs and river levels that resulted from below-average winter precipitation. Forecasters say that the snowpack in most of the Swiss, Austrian and Italian Alps is 60-70% below its typical amount for early March.
The lack of snow across the Italian Alps will play a significant role in adequate river levels and flow rate downstream this spring. Snowmelt from the Italian Alps every year helps to ease irrigation struggles for the key agricultural resource of the Po River Valley and is a primary source for the Po River itself which empties into the Adriatic Sea near Venice, Italy.
In Italy, an influx of moisture during the first half of spring could also lead to an increased danger of severe weather, which could usher in various threats such as damaging winds, hail and flash flooding. However, early-spring moisture may prove beneficial to only the short-term drought ongoing across the region.
As the impacts of the sudden stratospheric warming event gradually cease across northwestern Europe by late March, a trend of high pressure can take control over the region to promote drier and warmer conditions. However, shots of moisture will still be possible, making forecasters believe that precipitation totals this spring can trend near the historical average.
From France to Poland, warmth will gradually build as spring gets into full swing, and the topic of severe weather will come to the forefront of the conversation as the traditional severe weather season in Europe begins. In early to mid-March, severe thunderstorms already ignited across parts of France, resulting in a damaging tornado that struck Pontarion, France.
Forecasters have specifically highlighted Germany and Poland as two countries that are facing a significant severe weather risk this spring, along with neighboring areas north and east of the Alpine regions.
Parts of western Spain and Portugal will also face an unsettled start to spring, which may help to moderate how quickly the heat builds across the region although much of eastern and southeastern Spain has recorded only about 50-75% of its typical rainfall from last autumn to mid-March and warmth can potentially ramp up rapidly across this sector this spring.
“As spring begins, we can see unsettled conditions kick up across the Iberian Peninsula before the pattern trends drier and hot later in the period,” explained AccuWeather Senior Meteorologist Alan Reppert.
Much of southeastern Europe will continue to face warm conditions this spring, becoming even warmer by May and early June.
Locations from Rome to Bucharest, Romania, which were experiencing mid-March temperatures typical of late April, will maintain this warming trend over the course of the next few months, accompanied by occasional rounds of wet weather. During early spring, it is not out of the ordinary for storms to fire up across the Balkans into southeastern Europe.
Produced in association with AccuWeather
