Europe April 2020 Outlook

Written by on March 31, 2020 in Rest of Europe, United Kingdom & Ireland with 0 Comments

A strong, stable stratospheric polar vortex dominated much of the 2019-20 boreal winter, driving warm oceanic air across the continents. We’ve almost certainly observed the warmest winter since the beginning of the satellite era (1979) throughout the Northern Hemisphere.

Globally, January 2020 was earth’s warmest since the beginning of the satellite era in 1979.

Following the blowtorch January, earth then witnessed it’s 2nd warmest February since 1979.

A record strong polar vortex at the close of December and again in mid-February drove an off-the-scale positive Arctic Oscillation, reinforcing the lack of polar air release into the mid latitudes. Lows exiting Canada/US with polar air entrainment helped bring some snow and somewhat less warmth during February and closer to average March for the UK.

Michael Ventrice

Individually, December, January and February was exceptionally mild. This was likely down to a record strong positive Indian Ocean dipole during the autumn of 2019 and with warm equatorial Pacific waters (west of the international dateline), this helped maintain a warm phases 4, 5 and 6 of the Madden Julian Oscillation.

The warm west equatorial Pacific fueled frequent thunderstorm activity which enhanced the mid-Pacific high/Aleutian low. By strengthening these two features, this tightened the polar jet stream and maximized the push of ocean not arctic air across North America. This was mirrored over the Atlantic with an enhanced Azores high/Iceland low.

Note the strong subtropical high vs arctic low pressure!

 

NOTABLE GLOBAL HEAT AND COLD MARKS FOR JANUARY 2020

Hottest temperature in the Northern Hemisphere: 42.0°C (107.6°F) at Vicente Guerrero, Mexico, 21 January
Coldest temperature in the Northern Hemisphere: -66.0°C (-86.8°F) at Geo Summit, Greenland, 3 January (dubious data)
Hottest temperature in the Southern Hemisphere: 48.9°C (120.0°F) at Penrith, Australia, 4 January
Coldest temperature in the Southern Hemisphere: -47.4°C (-53.3°F) at Concordia, Antarctica, 31 January

NOTABLE GLOBAL HEAT AND COLD MARKS FOR FEBRUARY 2020

Hottest temperature in the Northern Hemisphere: 43.0°C (109.4°F) at Kolda, Senegal and Kayes, Mali, 24 February
Coldest temperature in the Northern Hemisphere: -65.0°C (-84.9°F) at Geo Summit, Greenland, 28 February
Hottest temperature in the Southern Hemisphere: 46.8°C (116.2°F) at Richmond, Australia, 1 February
Coldest temperature in the Southern Hemisphere: -62.9°C (-81.2°F) at Concordia, Antarctica, 29 February
Highest 2020 average temperature to date (1 Jan-29 Feb) worldwide: 33.1°C (91.6°F) at Telfer, Australia
Highest 2020 average temperature to date (1 Jan-29 Feb) in the Northern Hemisphere: 31.0°C (87.8°F) at Choluteca, Honduras

How’s April looking?

So, the final breakdown or end-of-season stratospheric warming is underway, albeit slowly and so we’re seeing some release of arctic air into the mid latitude pattern hence the late season arctic outbreak for Europe as well as parts of the Western US and far-east Asia.

Check out the flip from cold to warm at 10mb over the Arctic.

Credit: Tropical Tidbits

Credit: Tropical Tidbits

Expect to see the return of a mid latitude blocking pattern which will weaken the eastward push of warm maritime air and increase anomalous warm and cold pools over North America, Europe and Asia.

It’s not uncommon for late season cold and snow following warm +AO/NAO winters and this year is a prime example with us seeing the first -NAO since November.

The weakening of the polar vortex is slackened the westerlies allowing the build-up of pressure over the North Atlantic initially driving arctic air south but move a southeast movement of the high, by the weekend, our winds blow from the Azores so a pretty typical up and down temperature regime can be expected but the key difference will be a much drier theme.

April could see record cold and snow for parts of Europe but as we progress through April high pressure is likely to push south and east and then retrograde back west from France to Italy but to France. The CFSv2 suggests a ridge position over France mid to late April which points to warmer, drier weather for the UK and Low Countries.

Tropical Tidbits

week 2

Tropical Tidbits

week 3

Tropical Tidbits

week 4

Tropical Tidbits

week 5

Tropical Tidbits

FEATURED IMAGE CREDIT: Iain Cameron

Tags: ,

Follow us

Connect with Mark Vogan on social media to get notified about new posts and for the latest weather updates.

Subscribe via RSS Feed Connect on YouTube

Leave a Reply

Top