Showing posts with label climate. Show all posts
Showing posts with label climate. Show all posts

Sunday, 5 July 2026

June 2026 heatwave diary

At first I wanted to call it a "2026 heatwave"  but how can I assure in early July it will be the only such intense and abnormal hot spell this summer?

Tuesday, 16 June 2026
Judging by average temperature for the first half of the month, so far this is the coolest June since 2014. with hindsight, it turned out to be over 2 Celsius degrees warmer than 1991-2020 average in Warsaw.

Saturday, 20 June 2026 – Sunday, 21 June 2026
The first two days this year with highs above +30C, the latter humid and stormy. Around that time long-term forecasts hint at serious heatwave incident. At first they seem to be a model error, but with each next update, the heat dome prediction solidifies.

Thursday, 25 June 2026
Here it begins. Night-time low of +15C means at dawn it's still pleasant and one can keep the dwelling cool. Inside: between +21C and +24C. Temperature tops at +31C, so no tragedy.

Friday, 26 June 2026
The night is not that chilly, no colder than +18C, afternoon high of "mere" +31C, which is relatively bearable vs. what lies ahead. Inside: between +22C and +24C, humidity 60%

Saturday, 27 June 2026
I return home from an open-air party around midnight. At that time temperature in Powsin on the verge of Las Kabacki stood at +21C, while at the same time in Ursynów it declined to only +24C. Urban heat island proven existent. The last night when pre-dawn temperature dropped below +19C. In the morning temperature shoots up to climb to awful +34.7C, nearing the June maximum temperature record of +35.3C set on 26 June 2019, which is bound to be broken tomorrow. A country-wide June maximum temperature record for Poland has been beaten. Weather station in Słubice reported +38.5C, vs. previous record of +38.3C set also on 26 June 2019 in Radzyń. Inside: between +20C (air humidity above 70%) and +25C (air humidity just below 60%, not nice).

Sentence to be pondered upon: "Our houses have been built for a climate which no longer exists." For decades the primary concern was how to keep the dwellings warm during the colder half of the year, while growing frequency, intensity and duration of heat waves necessitate also keeping dwellings cool when outside it's well above +30C.

Sunday, 28 June 2026
First tropical night this year, with low of +20.4C in Warsaw. In western Poland minimum temperatures measured do not drop below +25C. From early morning the temperature soars. At 9:00 it reaches +30C, at noon it climbs to +35.7C, setting a new short-lasting heat record for the capital of Poland. Late in the afternoon a country-wide record (+40.2C measured on 29 July 1921 in Prószków near Opole) is shattered. The weather station in Słubice officially reports a high of +40.5C. Warsaw's highest ever temperature of +37.0C measured on 8 August 2013 is rendered outdated with a new readout of ghastly +38.1C. Inside: between +25C (air humidity 60%) to +26C (air humidity 55%). Awful, but cool compared to the oven outdoors.

The sentence to be pondered upon (continued). Air conditioning is a quick fix, lets one function properly, but has its dispersed cost. Prevalent in the US, seldom installed in private dwellings in Europe. With the current electricity output from solar panels it can be powered with nearly green energy during the day. This is the theory. In recent days around midday no more than 60% of energy output in Poland came from PV, while in the evenings demand for energy in Poland was satisfied in over 80% from conventional units, i.e. burning fossil fuels. Bear in mind AC removes the effect, not the cause. Walls give off heat after the sunset and you need to run AC overnight too to keep a dwelling cool and unless the electricity comes from a battery storage charged up during the day, you need conventional energy to power the AC. Besides, AC blows out hot air outside a cooled off building, thus increasing temperature to its neighbours and intensifying the urban heat island effect. I believe primary investments in thermal modernisations should involve proper insulation and protection from heat, not to let it trespass into a building and use of AC to augment it, when construction measures (thick insulation on walls and roofs, triple-glazed windows, external blind rollers, trees giving shade, ripping off paved urban areas) are insufficient. My take on duplicity of architects has been laid out here and I uphold it. I believe a balanced take is presented here.

Monday, 29 June 2026
With a minimum temperature of +24.7C last night was the warmest ever in Warsaw. I slept with windows closed, opened them after waking up at 4:00 a.m., to lock up the flat at 6:30 a.m. and head for air-conditioned office. Outside around 7:00 a.m. it was already +27C. To my surprise, underground stations and trains have not been warmed up horridly, I would hazard a guess it was around +25C inside. At Rondo ONZ station, despite early hour, droves of people were rushing to offices to find corporate shelters from heat. I admit it felt nice to cut off the awful heat, with today's high of +36.0C. No storms nor heavy rain have haunted Warsaw. Inside: temperature slowly increases to +27C (humidity: 60%), no longer comfortable, not yet tragic. Today administration of the building I live in issued a permission to install external blind rollers in windows of my bedroom and kitchen, both facing north-eastern side. In previous years, they were unnecessary, as the south-western living room ones did their job well enough. During the current heatwave I could swelter at 6:00 a.m. in my bedroom.

On both 28 June and 29 June daily temperature in Warsaw averaged out +30.6C, beating the previous record of +29.3C set on 8 August 2015.

Tuesday, 30 June 2026
The third tropical night in row. With temperature reaching a low of +21C it brings a minimum relief and lets the dwelling cool down a bit. Around 6:00 a.m. a short shower comes over Warsaw. It gives some little respite to the dried-up soil and leaves the air humid. Afterwards the heat is less tolerable, despite lower absolute temperature (max. +32C). Temperature creeps up above +30C around 2:00 p.m. which looks luxuriously cold. Inside: between +24C (humidity: 70%) and +27C (humidity: almost 60%).

Wednesday, 1 July 2026
The fourth tropical night in row, with low of +21C. In the morning outside it feels much better than inside, where neighbours' walls heat up mine. The afternoon is sultry, with high of +32C and much vapour in the air. Late evening brings a thunderstorm which puts the period of intense heat to a long-awaited end. Chasing away the warmth accumulated in buildings will take a while. This is formally the last day of the heatwave, with tomorrow expected to fall overnight to +17C and climb to +27C in the afternoon. Next days are about to be cold (in July terms) and I keep fingers crossed for that forecast.

The heatwave formally lasted 7 days and was not as awful as 15 days in a row with maximum temperature above +28C in August 2015. Until early July we have had so far 9 days this year with day-time highs above +30C, vs. long-term average of 9.5 days per year (1991 – 2020 benchmark period) and maximum number of such days of 24 in a year (2015 and 2024).

Sunday, 5 April 2026

Winter Timeline 2025/26

No, there was no consensus in terms of long-term forecasts for this winter, albeit more reputable meteorologists’ model pointed at warmer than average cold season.

 

The record-late incidence of heat was followed by a cold blast. In many places in Poland first frosts were observed in the last days of September. In Warsaw first ground frost was reported on 2 October 2025 and the first frost (dawn-time low of –1.2C) on 3 October 2025. It was the earliest first frost since 2001, occurring 15 days earlier than long-term average. October 2025 as the coldest since 2016, though in line with long-term average, deserved a separate summary.

 

The first half of November 2025 was relatively warm and frost-free, then the second half made up for it. The winter timeline is launched later than in 2024 (21 November), 2023 (17 November) or 2022 (17 November), but earlier than in 2021 (26 November) or 2020 (30 November).

23 November 2025
After a frosty night flurry begins around 8:00 a.m. and with some little breaks keeps slowly falling until evening. Not warmer than –1C.

24 November 2025
Snow falls on and off. Temperature crawls above 0C after sunset, suggesting nasty conditions ahead.

25 November 2025
Mild thaw, drizzle washes the snow away. Ghastly damp, no warmer than +2C.

26 November 2025
It was supposed to snow heavily, but as temperature oscillated close to +2C, it rains heavily.

27 November 2025 – 30 November 2025
Somewhere on the verge of autumn and winter, with overcast skies most of the time and temperature going through the point of freezing several times.

November 2025 was slightly warm. Average temperature in Warsaw was +4.4C (vs. long-term average of +3.8C). Stats:
- month-time high: +16.8C on 2 November 2025,
- month-time low: –3.9C on 24 November 2025,
- the warmest day: 2 November 2025 (daily average of +12.3C),
- the coldest day: 23 November 2025 (daily average of –1.6C)
- number of days with snow cover: 2,
- the highest snow depth: 3 centimetres on 24 November 2025 and 25 November 2025.

 

1 December 2025 – 8 December 2025
Late autumn returns, with fogs, poor air quality, intermittent drizzle and nasty deficiency of sunshine (except for 2 hours before sunset on 4 December and 1 hour around midday on 8 December). Temperature ranging from 0C to +9C. Not a sign of actual winter in sight.

9 December 2025 – 11 December 2025
Forecasters predicted record-breaking warmth, while temperature creep into low double-digits, with remarkably high night-time lows close to +10C. Some rainfall, some sunshine.

12 December 2025 – 15 December 2025
Getting colder, sliding from mid-autumn to late autumn.

16 December 2025 – 22 December 2025
Weather slowly crumbling from late autumn into pre-winter, accompanied by foggy greyness, with a depressing shortage of sunshine.

23 December 2025
Of note is the two-hour snow shower in the evening which symbolically ends the autumnal streak in December. Sadly, it falls on warm ground before temperature breaks into negative territory, hence almost no traces of it linger.

24 December 2025
Was supposed to be sunny from dawn, but skies clear up around midday. Day-time high no warmer than –6C, making it the coldest Christmas Eve since 2002, yet sadly a snow-free one.

25 December 2025
First double-digit frost this winter. Clear blue skies over the entire day. A tad warmer.

26 December 2025
Warnings of a freezing drizzle (which begins to fall at –4C) have been spot on. Large swathes of central Poland are turned into ice rinks, leading to numerous accidents. Forecasters do not get it right temperature-wise, as it does not thaw out.

27 December 2025
The freezing drizzle continues, while most of the day temperature hovers close to 0C, which means near ground it remains colder and icy conditions persist.

28 December 2025 – 29 December 2025
Two days of thaw before winter hits.

30 December 2025
Little snow showers on and off, while a proper blizzard comes after sunset. It snows all night then.

31 December 2025
Wake up to behold a thick blanket of snow. 12 centimetres is the highest day-time snow cover increase since early April 2022. The day is bright, but then skies cloud over and lush flurry begins late into afternoon and goes on until late evening…

December 2025 was very warm. Average temperature in Warsaw was +2.4C (vs. long-term average of –0.1C). Stats:
- month-time high: +11.7C on 10 December 2025 (not truly impressive, the warmest moment in December since New Year’s Eve in 2022),
- month-time low: –11.8C on 25 December 2025 (one and only night with double-digit frost in the entire month),
- the warmest day 10 December 2025 (daily average of +9.8C, scent of spring was in the air),
- the coldest day:
25 December 2025 (daily average of – 8.4C, also the coldest Christmas Day since 2002),
- number of days with snow cover: 2,
- the highest snow depth: 12 centimetres on 31 December 2025.

 

1 January 20262 January 2026
Snow showers and mild thaw. Winter gives a little relief, although the snow cover on New Year’s Day is the highest since… January 2013. It occurs to me it might be the only incidence of above-zero temperatures this month.

3 January 2026
Same weather pattern as yesterday, except for sub-zero temperatures only.

4 January 2026
More sunshine, still with some snow showers. Mild frost.

5 January 2026
Snow showers fortunately cease. More sunshine, at the expense of a frosty morning.

6 January 2026 – 9 January 2026
Little sunshine, no new supplies of the white powder. Ghastly chilly, with double-digit frost most of the time.

10 January 2026
Below –15C at dawn and clear blue skies. Soon it clouds over and some snow showers haunt Warsaw. Snow falling at temperature below –10C is a rare phenomenon, yet observable.

11 January 2026
Light snow in the morning, heavy snow in the evening. At least has got somewhat warmer, temperature rises above –5C.

12 January 2026 – 13 January 2026
Two snow-free days with moderate winter, i.e. day-time highs close to –3C. Meteorologists warn of a freezing precipitation coming over soon.

14 January 2026
A foggy morning, a snowy, then a rainy evening. The major problem is that it rains, but it does not thaw out. Raindrops falling on a frozen ground at –3C turn into ice immediately.

15 January 2026
The thaw lasts 16 hours and temperature over that period tops at +1.1C. We are unlikely to see above-zero temperatures by the end of the month.

16 January 2026
Chilly, kind of bright. The last day with single-digit frost before a long period of big freeze ensues.

17 January 2026 – 22 January 2026
Stable, a bit boring, yet spirit-lifting weather driven by a high pressure system. Cloudless skies from dawns to dusks. Morning lows between –14C and –11C, afternoon highs from –6C to –1C.

23 January 2026 – 25 January 2026
Sun hidden behind clouds, with intermittent light snow showers. Single-digit frost.

26 January 2026
Freezing rain in the morning, then comes a mild thaw which at least melt the thin layer of ice being the aftermath of the accursed precipitation.

27 January 2026
Again, the temperature gently climbs above zero, with little effect to the frozen ground.

28 January 2026
Waking up to the sight of fresh snow, raising snow cover by 4 centimetres in total and hiding the dirty old snow.

29 January 2026 – 30 January 2026
Cloudy, temperature close to –5C, with wind chill reaching –15C. Temperature-wise, it is a lull before the storm, namely the most intense cold snap since early February 2012.

31 January 2026
Just –14C in the morning, –8C in the afternoon, then the temperature plummets. Clear blue skies and sunshine do not bring relief, as wind brings down the temperature felt by a human body below –20C.

January 2026 was anomalously cold. Average temperature in Warsaw was –5.5C (vs. long-term average of –1.5C). It was the fifth coldest month in Warsaw in the twenty-first century, after:
1. January 2006 (–8.3C),
2. January 2010 (–8.0C),
3. December 2002 (–6.6C),
4. February 2012 (–6.1C).
Stats:
- month-time high: +3.1C on 2 January 2026,
- month-time low: –15.5C on 10 January 2026 (a classic January low, there were 16 days in the month with lows below –10C),
- the warmest day: 2 January 2026 (daily average of mere +1.5C and the only day in the month with average temperature above freezing),
- the coldest day: 31 January 2026 (daily average of – 11.8C),
- number of days with snow cover: 31,
- the highest snow depth: 25 centimetres on 5 January 2026.

 

1 February 2026
Morning brings the lowest temperature this winter so far, –17C, which is still warmer than forecasted. In the afternoon temperature shoots up to –9C. Full sunshine. In the evening wind chill reaches ghastly –25C.

2 February 2026 – 3 February 2026
Awfully cold, with lows below –19C. Morning wind chill of –27C. Full sunshine.

4 February 2026
A fresh supply of new snow comes up before dawn. Still chilly, no warmer than –7C in the afternoon.

5 February 2026
One nuisance is swapped for another. Freezing drizzle before dawn. Then the thaw does not come up.

6 February 2026 – 7 February 2026
Foggy, damp, dull days. The thaw lasts 41 hours and over that time temperature does not rise above +1.2C. Drizzle on and off.

8 February 2026
Let is snow, let is snow… Gone is the thaw, but shall return in four days, maybe even for a while.

9 February 2026
A beautiful, sunny, bright, yet chilly (quite frosty) day.

10 February 2026
Getting warmer hour by hour. Freezing rain (fox the sixth time this winter) heralds the imminent assault of masses of warm air.

11 February 2026 – 13 February 2026
First proper thaw since late December, with temperature reaching +5C for the first time since nearly 2 months. The first day brings plenty of sunshine, while next two are foggy and gloomy. This means a slow farewell to the snow lying on the ground since 30 December.

14 February 2026
By the time the frost returned, snow cover in Warsaw dwindled from 14 to 5 centimetres. Frosty, gloomy, with no spring on the horizon.

15 February 2026
Getting colder hour by hour, skies clear up in the afternoon.

16 February 2026
In the morning temperature drops to nearly –15C. Sunny by late afternoon. Wind chill again is a nuisance.

17 February 2026 – 18 February 2026
Single-digit frost. Snow falls on and off, but mid-term forecasts indicate a major thaw which would wipe out all traces of winter. Most likely not sustainably, but any relief is welcome.

19 February 2026 – 20 February 2026
Mostly sunny, with lows close to –10C and afternoon just below 0C. The late-winter mode I adore, with sun shining high and days getting visibly longer.

21 February 2026
The morning as frosty as on previous days, then temperature shoots up to reach +1C early in the afternoon and retreat soon to 0C, as a flurry begins. A few days of relief from cold and snow ahead, but most likely the winter has not said its last word (with hindsight – it said).

22 February 2026 – 23 February 2026
A thaw in overdrive, dull, cloudy and rainy. The snow disappears.

24 February 2026 – 25 February 2026
Colder now, yet warmer than over most of the winter, still average daily temperature remains above freezing.

26 February 2026 – 28 February 2026
Getting warmer day by day, into warmth abnormal for this time of year (well into double digits on the last two days of the month), which is a pleasant anomaly after weeks of enduring temperatures lower than average. Sunshine brings a smile on my face. Gusty wind does not let one feel like in April.

February 2026 was cold. Average temperature in Warsaw was –2.5C (vs. long-term average of –0.4C). This means we had two colder than average months in a row in Warsaw for the first time since April and May 2021 (for winter months since February and March 2018). Stats:
- month-time
high: +16.3C on 28 February 2026 (colder than in late February in 2021 and 2024),
- month-time low: –19.5C on 3 February 2026 (ghastly, with wind chill of –27C),
- the warmest day: 28 February 2026 (daily average of +7.3C),
- the coldest day: 2 February 2026 (daily average of –15.3C, the coldest day in Warsaw since 18 January 2021),
- number of days with snow cover: 23, snow cover continued to lie on the ground in Warsaw for 55 consecutive days, the longer streak since 2009/10 winter (62 days in a row then).
- the highest snow depth: 20 centimetres, on 4 February 2026 and 5 February 2026.

Monthly temperature amplitude in February 2026 reached 35.8 Celsius degrees, which is the third-highest such measurement in Warsaw. The record set in March 1971 of 40.2 Celsius degrees (low of –21.6C on 5 March 1971, high of +18.6C on 21 March 1971, i.e. mere 16 days later) is awfully difficult to beat and March is probably the only month when it stands a chance to be beaten.

 

1 March 2026 – 10 March 2026
A boring weather pattern: sunshine from all to dusk, no rainfall (disturbingly), morning lows between –4C and +1C, afternoon highs between +10C and +17C.

11 March 2026 – 15 March 2026
A similar pattern to the one from the first decade of the month, with exception of lack of frost at dawn and with warmer afternoons (up to +19C). Still no precipitation!

16 March 2026 – 25 March 2026
Colder than in previous days, yet substantially warmer than it should be at this time of year. Some occasional showers, yet far too little to make up for deficiency of precipitation from the beginning of the year.

26 March 2026
Finally a long-awaited rainfall and the only day this month with day-time high below +10C.

27 March 2026 – 31 March 2026
Colder than over the most of the month, retreating from spring in full swing towards pre-spring.

March 2026 was abnormally warm, actually the warmest since records began. Average temperature in Warsaw was +7.7C (vs. long-term average of +3.2C and current record of +7.2C set in 2007). Stats:
- month-time high: +18.9C on 14 March 2026,
- month-time low: –3.7C on 7 March 2026,
- the warmest day: 14 March 2026 (daily average of +12.1C, a May-like weather),
- the coldest day: 6 March 2025 (daily average of +3.8C, the coldest day being warmer than long-term mean for the entire month),
- number of days with snow cover: 0.

In terms of precipitation, it was the second driest March in Warsaw since records began, with total precipitation of mere 2.7 millimetres (March 2022 with 1.7 millimetres remains unbeaten).

 

The winter is definitely over. Today the temperature in Poland’s capital may hit +20C for the first time this year. In the coming days we will cope with an inflow of cold here past the Easter and have to endure a few frosty morning, but hopefully the long-awaited spring will soon be in overdrive.

Sunday, 28 September 2025

The latest heat in Warsaw ever

As I am a weather and climate statistics freak, knowing nearly by heart the history of weather records in Warsaw and having written 14 winter timelines here, each weather event which modifies weather stats for Warsaw should not pass unnoticed on PES.

With a delay, I note the maximum temperature record for July was broken on 3 July 2025, when temperature peaked at +36.5C, beating the reading of +35.9C dated 31 July 1994.

Last Sunday, on 21 September 2025 day-time high in Warsaw reached +30.8C. It was the first incidence of heat (defined as maximum temperature in excess of +30C) in the third decade of September ever. Moreover, the latest heat record, until last Sunday set on 14 September 1951 was broken by 7 days. Those are stats for Warsaw stand-alone. Country-wide, the latest incidence of heat was reported on 27 September 2012 (Jarczew, +30.8C, in most Polish cities temperature on that day reached above +26C).

The record Warsaw will be difficult to be beaten quickly, as such inflows of hot air are infrequent (we had it on 1 January 2023 when temperature peaked at +18.9C). Lucky us, it haunted us in the second half of September, not in mid-July as in high summer temperature would be likely to get close to +40C.

A matter of short time will probably be a first incidence of heat in October in Poland. So far the record is +29.3C measured on 3 October 2023 in Legnica.

Warmth spells in months other than summer ones are welcome, but they are a part of a broader picture whose element is a drought ongoing for a decade. Deficiency of rainfall has lasted two months now and forecasts for October, full of sunshine and no consensus about above-average temperatures, give little hope for making up for it.