Sea surface temperature (SST) anomalies: strikingly warm waters in the tropical Pacific, with El Niño developing. Around Europe, seas are also far too warm after the record early heatwave: in the northern Mediterranean and Bay of Biscay anomalies even exceed the scale maximum of +5°C.

The heat dome (crazy 500hPa anomaly) of the last days brought record late-May heat to Western Europe, with freezing level over the Alps at 4,000–4,500m—data from Mont Blanc’s highest station (4,750m). The high weakens this weekend; no new heat dome is forecastes the next 2-4 weeks (GFS ensemble).

Whit Sunday and cloudless skies across whole Switzerland! At this time of year, this brings a max. of 14 to 15h of sunshine, depending on location, automatic measuring equipment+threshold values (120 or 200 W/m² direct solar radiation). Around the start of summer, up to 16 hours have been recorded.

With unusually high MSLP and record-breaking 500 hPa heights, the Alps enjoy splendid weather with often clear skies. The freezing level in the western Alps is already above 4,000 m. The next few days stay very sunny and become even warmer, with the first hot days and tropical nights.

Thanks to a prominent upper-level ridge, sunny weather prevails across the Alps, with some clouds only in the east. With record-breaking warmth aloft, the freezing level will continue to rise: on Tuesday, it is expected to reach up to 4,400 m above sea level over Switzerland.

There is still snow left in the Alps, and also locally in the Pyrenees. However, with record-breaking upper-level warmth (the freezing level over the Alps is expected to rise to around 4,500 m on Tuesday), rapid melting is now set to begin!

The much too cold spring of 2026 in Canada is now also coming to an end: by late May and early June, temperatures there will also become much too warm.

Calm, but rather cool Sunday across Europe — but a small thunderstorm developed to the west/northwest of Malta, triggered by a weak upper-level trough with temperatures of −15°C at 500 hPa and some humid low-level air advected from Tunisia.

The drought in Central Europe has regionally eased, with above-average rainfall during the first half of May 2026. Temperatures have been slightly below average so far, but this is expected to be more than compensated for by a warmer second half of the month. (graphics by JMA)

Every year now, the pre-monsoon heat (the hottest time of year in South Asia with temperatures well over 40°C) starts earlier & lasts longer - due to human-induced climate change - exposing 1billion people to deadly heat. @wwattribution.bsky.social www.worldweatherattribution.org/climate-chan...

No, the upper air observation situation in Alaska is not getting better. Alaska Wednesday afternoon 50 percent of possible upper air observations were missing. But thanks for asking. #weather @climatologist49.bsky.social @wxmanms1.bsky.social

Weather situation: trough over Central Europe – but what a trough! Exceptionally pronounced for mid-May. Spoiling the long Ascension weekend across Central Europe with clouds, rain, thunderstorms and lot of fresh snow in the Alps. Pleasant, dry and warm only in southern Spain and the Algarve.

False-colour satellite image from Terra/MODIS for Wednesday, 13 May 2026 at 09:05 UTC, with clouds shown in white and snow cover in blue. There is still snow in the Alps: more than last year, but the overall snow cover fraction is significantly below normal.

Brief, vigorous surge of Arctic air brought snow down to 700 m on Tuesday morning. Conditions are now improving: in the clean air from Greenland it is becoming increasingly sunny and clear. Tuesday night will be cold, with ground frost in lowlands and frost in the Jura, Prealpine and Alpine valleys

New multi-model monthly and seasonal forecasts are now available via climate.copernicus.eu launched with data from beginning of May. Most likely category for temperature ↙️and precipitation ↘️for summer (JJA) 2026.

Arctic air will cause a brief but intense cold snap in the Alps overnight into Tuesday: in the Allgäu, snowfall may reach as low as 700–800m, with fresh snow possible by the 06 UTC climate measurement. Oberstdorf (WMO ID 10948) had 3cm of snow on 17 June 1991—in the forenoon, so not in the stats.

According to ERA 5 reanalysis April 2026 was globally the 4th warmest. But global sea surface temperature were already 2nd warmest since 1940! And during 2026 a major El Niño is expected, peaking next winter. SST anomaly for September with cold blob in northern Atlantic and +IOD.

It’s slowly becoming summer in Greenland: with 24 hours of sunlight again as far south as 72°N (e.g. Upernavik) ... activities on the Greenland Ice Sheet have begun. Today, a supply flight with an LC-130H Hercules from Kangerlussuaq (max. +5°C) to Summit Station (3209 m, max. -16°C) took place 😎

According to the ERA5 reanalysis April 2026 was the fourth warmest globally and the eleventh warmest in Europe since 1940. Notably exceptional spring dryness, with March and April the driest on record regionally in eastern Central Europe !

Si vous êtes adepte des prévisions via les sondages, depuis quelques années Météociel propose un outil de lecture de sondage SHARPpy, souvent utilisé pour la prévision d'#orage. Il est disponible sur plusieurs modèles tels que AROME, ARPEGE, WRF 0.05° et 2 km, GFS et ECMWF/CEP ⤵️

Early summer southwesterly flow: thunderstorms now in western Prealps (moving to NE with 25 km/h), warm foehn in classic Alpine valleys (Upper Valais, Hasli-, Urner Reuss-, Rhine valley) with 27°C in Sargans, even 28.6°C in Innsbruck-University. Tomorrow cross alpine delta-P up to 8hPa—more foehn!

Large snow drift (sastrugi) seen on the Summit Station webcam atop the Greenland Ice Sheet (3,209 m), formed by strong south-easterly/southerly winds in recent days. Temperatures today up to −25°C; yesterday’s low −41°C. Clear and significant colder than usual until next Thursday.

April coming to a close. Probably 5th warmest on record. Canada still on the cool end of things, while Mongolia and large parts of China have been baking compared to the 1981-2010 baseline. The Pacific is slowly starting to built up steam / heat. www.karstenhaustein.com/climate

“Boring” high pressure? Big contrasts in small Switzerland: despite very strong solar radiation, the NE is cooler than yesterday with a very dry (dew point −3) supergeostrophic easterly wind. At the same time, thunderstorm over Upper Jura and southerly foehn over the Valais Alps (pressure gradient)

Some striking cirrus clouds this morning over eastern Switzerland and southern Germany: Cirrus floccus virgae (jellyfish clouds) … as seen from above (MTG) and below with a ceilometer.

Joy reigns: weekend and brilliant sunshine across whole Switzerland, with only few, small cumulus clouds. BUT: April to date is anomalously dry - only 1 (Sion) to 68 (northern Ticino) mm. Persistent dryness expected north of the Alps through month-end. 2According to ERA5: April 2007 was even drier.

Mean sea level pressure in Switzerland averages ~1018 hPa annually (ERA5, 1991–2020 climatology). Daily values peak in mid-January and reach their lowest in mid-April. The current high-pressure system with completely clear skies (Terra/MODIS overpass at 09:09 UTC) is highly anomalous 🤔

Nearly a month after Sunset, its much darker at the #southpole, but you can still see a little twilight on the horizon with a medium exposure on an #iphone. Here is a pic from winterover Michel towards the Dark Sector on the walk out to SPT. #Antarctica @NSF @doescience

A pleasant Monday in Switzerland with cumulus clouds along the Prealps (north+south) and near the snow line inner-alpine. Snow below ~1,500 m has mostly melted; higher areas still have snow, though below average: iconic Säntis has 371 cm (measurement below the summit) vs. record 816 cm in 1999!

Absolutely fantastic explainer on the quasi-geostrophic omega equation (and related aspects of atmospheric dynamics) from @roostweather.bsky.social 👏 www.youtube.com/watch?v=YmZi...

Another small but impressive cold-core low over the southern Mediterranean, near the Libya–Egypt border, is causing a severe sandstorm in Egypt (Cairo airport visibility below 500 m) as well as thunderstorms, detected by the MTG Lightning Imager.

In Central Europe, snow now remains only at higher elevations, while Lapland and Iceland are still heavily snow-covered. In the Alps, current snow cover is below average.

In the long-term average (ERA5), mid-March is the driest period of the year in whole Europe. By April, precipitation would normally increase. However, the first half of April 2026 has been too dry across large parts of Europe (according to JMA).

Something large appears to be burning along the Russian Black Sea coast (Tuapse), with activity starting at around 00:10 UTC. Terra-MODIS via worldview.earthdata

Alaska & Yukon Territory upper air observation availability so far in 2026. Continued lots of missing data in western Alaska (combo of staffing, hardware & comms issues). Not just an Alaska problem: lack of obs impact weather & climate reanalysis models globally. #akwx #weather @wxmanms1.bsky.social

Fascinating: March 2026 was one of the warmest months in the USA, while at the same time one of the coldest in Canada! The anomalies closely followed national borders and even the somewhat arbitrary division of calendar months. 🤔

The April, widely regarded as notoriously changeable and fickle in its weather, began in Central Europe much drier than usual, too warm in the west, and slightly too cold in the east. According to the ECMWF sub-seasonal forecast, similar conditions are expected to continue next week.

We now have 13 different models with 637 different ensemble members with El Niño forecasts out through at least September 2026. They suggest a best estimate of 2.2C for September; interestingly ECMWF (which was seen as particularly hot when it came out) is right around the middle of the pack:

A weak cold front brings cloud and rain to eastern Switzerland and southern Germany, while first plume of Saharan dust reaches the Balearics (Valencia ceilometer in 3–4 km altitude). More dust from Algeria spreads over the western Mediterranean on Saturday, only brushing the Alps.

Arctic sea ice reached its annual maximum extent in mid-March, once again at a very low level, comparable to 2025. Although areas around the North Pole are already experiencing 24-hour daylight, temperatures are still very low: at a Snow Buoy (AWI) at 89.12°N, it is still around -26°C!

Clear and often sunny weather in the Alps, according to the Terra-MODIS satellite. Locally, more than 12 hours of sunshine is possible today, with highs ranging from just 15°C in northern Austria to 26°C in northern Italy and southern Switzerland.

About 2-weeks after #sunset at the South Pole, our winter overs Michel and Anjali are getting some great views of the darkening skies. Here SPT and DSL are being backlight by a nearly full moon. #Antarctica @NSF @doescience

Still some low cloud along eastern Prealps, otherwise Easter Monday often sunny across Switzerland. With north-easterly wind, northern and eastern parts of the country are 2 to 6°C cooler than yesterday. Snow cover (shown in blue) has melted significantly over the holidays: decreasing by 10 to 40 cm

Easter Sunday brought the northern side of the Alps its highest temperatures of the year so far: In Switzerland readings ranged from +3°C (Gornergrat, 3,130m) to 25.0°C (Sion). Now, the first local showers and thunderstorms are following, moving east-southeast at 50–60 km/h.

March 2026 globally fourth warmest, but second warmest in Europe since 1940! Credit to @climatologist49.bsky.social

A sunny Good Friday in Switzerland, with still a lot of snow (coloured blue) above ~800 m amsl —especially in the northern Prealps, though not record amounts. Also across the entire Alpine region, there is currently more snow cover than usual.

This is a great website to see where #ARTEMIS2 currently is! artemistracker.com

ICYMI, there were some pretty cool satellite signatures of the Artemis II launch yesterday: cimss.ssec.wisc.edu/satellite-bl...

Saharan dust over the Canaries has been drawn into the circulation of an unremarkable low southwest of the islands. Thunderstorms (LI flash areas), fueled by unstable tropical air, remain confined to dust-free zones ahead of the low.

Significant quantities of dust still over Canary Islands from recent haboob event. Meanwhile, with the development of storm Erminio over Sicily, a severe sandstorm is currently affecting Crete, featuring gusts exceeding 100 km/h from the south.