-22 °C today in Lahti, Finland. The coldest morning so far this winter. This is how it sounds when walking outside. Sound on!

2025 was the warmest year on record for Central England in a dataset that starts in 1659. (Daily data available since 1772.) www.metoffice.gov.uk/hadobs/hadce...

Meanwhile in Helsinki (Kaisaniemi) Finland: the season's first snow finally arrived today. Approximately the same latitude and winter climate as Juneau, Alaska. One of the latest first snows on record for Helsinki.

As far as I know, here are all known cases of ≥ 31 m/s mean wind speed observations in Finnish sea areas: 31 m/s Valassaaret 1971 31 m/s Korsnäs 1975 (twice) 31 m/s Hanko 1995 32.5 m/s Kökar 2019 33.5 m/s Rauma 2024 31.4 m/s Rauma 2025 (yesterday)

According to FMI wave buoy measurements, the significant wave height reached 11.1 meters last night in the Bothnian Sea. If true, it would be the highest waves ever recorded in the Baltic Sea. en.ilmatieteenlaitos.fi/wave-height?...

Jo 100 000 sähkötöntä taloutta. #Hannesmyrsky sai siis nimensä myrskyjen "raskassarjalaisiin" ja lukema oikeuttaa pääsyn merkittävimpien myrskyjen listalle: www.ilmatieteenlaitos.fi/merkittavia-...

Kovin keskituuli toistaiseksi tuttuun tapaan Rauman Kylmäpihlajalla 31,4 m/s. Vastaa ankaraa myrskyä, joka toistuu noin kerran 10 vuodessa. #Hannesmyrsky

Hirmumyrskyä tuntureilla. Saanalta viimeisin tuulihavainto tunti sitten 38 m/s (puuskat 44m/s). Sen jälkeen tiedot puuttuvat. Ehkä laadunvarmistus luulee havaintoja virheellisiksi tai voimakas tuuli on rikkonut mittarin.

Boxing Day in Orimattila, Finland at 61°N latitude. Wonderful weather, although at this far north you'd expect to have some snow at Christmas.

The last week of 2025 will bring us the strongest windstorm of the year. Forecasted maximum gusts of ~140 km/h (39 m/s) and the affected area are more or less similar to the recent extreme northerly windstorms in Finland (Aapeli 2019, Lyly 2024).

The administration of US President Donald Trump intends to dismantle the National Center for Atmospheric Research (NCAR), a world-leading Earth-science centre in Boulder, Colorado. go.nature.com/4pjzUqB

🌊📉 Sea surface temperatures have… come back down. After the big global jump in 2023/24, SSTs are now back at below pre-jump levels in November (climatereanalyzer.org/clim/sst_dai...). Climate surprise or expected? What role does climate variability play? Let’s try to unpack 👇

The new GloSAT temperature dataset extends our observational estimates of global temperature change back to 1781 Blog: climatelabbook.substack.com/p/new-estima... Paper by Morice et al.: essd.copernicus.org/articles/17/...

Unfortunately it seems likely that southern Finland will see a widespread green Christmas this year. The largest temperature anomalies will occur just before the holidays. Resembles a bit the situation in December 2020 when it was last time widely a snowless Christmas.

A rare phenomenon this morning in Helsinki ☀️

#CopernicusClimate has released its first data from the Copernicus pan-Arctic Regional Reanalysis (CARRA2): 2.5 km pan‑Arctic coverage, 24 years of data in the Climate Data Store, more realistic physics & improved details for local extremes, lots of added details with respect to ERA5. ⬇️

By the finest of margins, ERA5 shows a reversal of the daily-mean 10 hPa 60°N zonal-mean zonal winds on 28 November to –0.13 m/s. That nominally ties with 28 Nov 1968 as the earliest major sudden stratospheric warming on record in ERA5 post-1958 (when stratospheric observations increased).

Sunshine durations so far in December. Zero hours almost everywhere in Finland. No wonder if it's felt dark recently.

2025 is on course to be joint-second warmest year. The #C3S Climate Bulletin reports that November was 1.54°C above pre-industrial levels, making it the third-warmest November on record. The 2023–2025 average is likely to be the first three-year average exceeding 1.5°C. Find more info ⬇️

New evidence suggests weather persistence is increasing in the northern mid– and high latitudes due to climate change. So far, I’ve been skeptical as the signal seems small compared to natural variability, but maybe it’s time to update my thinking. www.nature.com/articles/s43...

This morning's ECMWF deterministic forecast simulates an extreme scenario: +11 °C in Finland in mid-December. Most likely does not verify as such but gives perspective of what it possible in today's climate under the current large-scale weather pattern.

New ECMWF seasonal forecast came out two days ago, suggesting still NAO+ dominated late winter. The surprisingly high run-to-run consistency indicates a predictable signal that was "visible" to the model already in September. Perhaps originating from the tropics (i.e. ENSO)?

Olin Asiastudio-podcastin vieraana juttelemassa mahdollisesta Atlantin kiertoliikkeen romahduksesta ja sen vaikutuksista. Paljon asiaa, eikä kaikkea tietenkään muistanut edes kertoa! www.youtube.com/watch?v=lnRC...

Here are the press release on the retraction of one our Nature papers www.pik-potsdam.de/en/news/late... some explanations www.pik-potsdam.de/en/news/late... the journal's comment www.nature.com/articles/s41... Please note: The fact that climate change causes huge economic damages is not disputed..

Helsinki, Finland, is currently on track for the 2nd warmest calendar year on record, trailing only 2020 📈🌡️ To avoid this, December would need to be more than 2 °C colder than average, a scenario that seems unlikely at this point (based on sub-seasonal forecasts).

I've had the privilege of being Co-Editor-in-Chief of @rmets.org Weather since September 2020, first alongside @eddywx.bsky.social and then Regan Mudhar. Now please join me in welcoming Ben Maybee as the next Co-EiC! rmets.onlinelibrary.wiley.com/doi/10.1002/...

The temperature anomaly difference between the south and north was exceptionally large in November: it was the first occurrence when the anomaly in Sodankylä was < -2 °C and in Helsinki > +2 °C during the same month! Records kept since 1901.

Näin Euroopan ilmasto voi muuttua 2100 mennessä yle.fi/a/74-2019207... Hieno artikkeli tehty FMI-Yle yhteistyöllä. Laskin Ylelle ilmastomalliennusteet pyynnöstä.

500-year paleoclimate record inferred from Greenland Juniper wood contextualizes current climate warming "By providing a 500-year context for long-term climate variability, it has been confirmed that the observed recent warming is unprecedented" www.nature.com/articles/s41...

Kaamos alkoi Utsjoella, mutta Inarissa vielä paistaa. Ukonjärvi -27 🌞

The importance of weather and climate science in the insurance industry "Insight" article in @rmets.org Weather from @mattpriestley.bsky.social & @hcbloomfield19.bsky.social doi.org/10.1002/wea....

November-to-date temperature anomalies in Finland. It is somewhat rare to have such a strong contrast between south and north: usually temperature anomalies are well correlated over large (~1000 km) distances.

🚨New paper on heatwaves in a net zero world 🚨 In our study, led by @sarahinscience.bsky.social, we find that the intensity, length and frequency of heatwaves do not return to pre-industrial levels under net zero - and in many regions barely improve at all. iopscience.iop.org/article/10.1...

Extremely cold conditions have prevailed under surface inversion in Lapland now for several days. Some stations have not risen above -25 °C even in the daytime, which is exceptional for the time of the year. For example, Kittilä Lompolonvuoma *highest* today is -27.1 °C.

Can simple circulation analogues detect observed changes in extreme rainfall? In many cases, no. Rainfall is too complex and circulation alone cannot predict it. 🧵1/2 🌧️ New paper 🌧️ iopscience.iop.org/article/10.1...

Now, a majority of the 101 ensemble members in the ECMWF subseasonal forecast are indicating a major sudden stratospheric warming (SSW) event next week. November SSWs are extremely rare: over the last 67 years, there is only one known event (Nov 1968).

The global record 134 °F surface temp, measured in Death Valley in 1913, is "implausible" based on other records from that date, claims a paper in #BulletinAMS. The authors suggest the temperature was recorded at an improper location. More on the blog: https://bit.ly/3LCKPgS

It’s almost like something dramatically changed after the Industrial Revolution! (figure via Ed Hawkins)

📈🚨NEW: Extreme heat events are increasingly threatening to become mass mortality events. In @natclimate.nature.com today, we project tens of thousands of deaths in a single week across Europe if extreme heat domes coincide with rising global temperatures. www.nature.com/articles/s41...

"For example, if August 2003 meteorological conditions recur at the recent annual global temperature anomaly of 1.5 °C, we project 17,800 excess deaths across Europe in one week, rising to 32,000 at 3 °C." www.nature.com/articles/s41...

Some kind of quasi-stationary "sea-effect rain" hit yesterday in SE-Finland, producing an extremely localized total of 79 mm in Virolahti Koivuniemi. This is the highest daily rainfall ever recorded in Finland for the Oct–Dec period. Radar products indicate even higher amounts, up to 100 mm.

Vaihtelua piisaa Suomen säässä. Pohjoiseen napakoita pakkaslukemia. Etelärannikolle rankkoja sateita. Savukosken -28,3 °C on talvikauden kylmin mittaus tähän mennessä. Virolahdella vettä on tullut 12 tunnin aikana jo liki 55 mm.

Breaking: Virolahti Koivuniemi in SE-Finland has provisionally broken the national daily rainfall record for November with 58.2 mm by 21.00 local time and still counting. www.ilmatieteenlaitos.fi/saa/virolahti

Now that the Sept and Oct data are (belatedly) in, it looks like 2025 will be the second warmest year in the record (~80% probability). The last three years are in a class of their own.

Winter tightens its hold in Lapland. At the moment -28.3 °C in Savukoski Tulppio with > 20 cm of snow. The coldest so far this winter in Finland. However, much like in 2023, large parts of the northern hemisphere are unusually warm again (except Fennoscandia).

Lokakuun Ilmastokatsaus-lehdessä on kansankielinen artikkeli uudesta tutkimuksestamme Lapin kesälämpötiloista vuosilustoaineistojen valossa, ja siitä miten kesä 2024 oli alueella lämpimin 2000 vuoteen. www.ilmastokatsaus.fi/lapin-vuosil...

Consequences of the cold air outbreak. First snow of the winter now in Lahti, Finland 🌨️

Published today in Earth System Science Data: The Global Carbon Budget 2025 essd.copernicus.org/preprints/es...

The ensemble mean from today's IFS subseasonal run almost predicts the earliest major sudden stratospheric warming on record 😮 Will be interesting to see if this signal progresses as it is just on the cusp of typical SSW prediction lead-times – daily runs of 101 members can still vary a fair bit

📢Global Carbon Budget 2025📢 Fossil CO2 emissions continue to rise in 2025 while the terrestrial carbon sink recovers to pre-El Niño strength. The key findings are covered in two reports this year: * ESSDD (preprint): essd.copernicus.org/preprints/es... * Nature: www.nature.com/articles/s41... 1/