Sunday 17 August 2014

Relief from the heat

The summer of 2014 in Poland will not probably go down in the history of as remarkably hot, sultry, rainy or stormy. Temperatures so far have been slightly above long-term averages, precipitation not abnormal. For the record, weather summary of the period from 14 July 2014 to 13 August 2014 on Warszawa Okęcie weather station from excellent ogimet database is presented on the screenshot below.

One can easily notice no temperature records have been broken, with summer-time high below +33C, contracting to +37C recorded on 8 August 2013. What is quite remarkable about the analysed interval is that over 29 consecutive days, starting 15 July ending 12 August the temperature has not dropped for a single moment below +15C. There were days when day-time highs were well below +25C, but there was no night nor morning when one could feel a really cool breeze. Slightly similar, yet reverse pattern could have been observed in early 2010, when from 1 January 2010 to 29 January temperature in Warsaw did not rise above freezing at all.

Such freak of weather had several implications. For holidaymakers staying in Poland it meant good news. Water in lakes during the period of prolonged heat warmed up to well above +20C. Even the Baltic sea near Polish shore was unusually balmy, with water temperatures reaching up to +18C or +19C contrasting to no more than +15C most people expect. From what I heard in some places north-easterly drifts brought in cool waters from the northern parts of the Baltic Sea, hence beaches were chock full of people unwilling to bath in the sea, cooler than air by some twenty degrees.

Those staying in town had to endure heat in their dwellings. The better insulated the building, the longer it takes for it to warm up and then to give off heat. After a fortnight of high temperatures many dwelling were warmed-up solid and even opening all windows for a night gave little relief. Fortunately, if one has windows on two sides of a dwelling, draught is an excellent method for cooling down the interior when temperature outside drops. The place most affected by the prolonged heat seems to be the underground, which each year at the onset of summer is the oasis of pleasant chill and then resists to give away heat.

I hope the current spell of typical Polish moderate summer, a blend of sunshine and rain showers, lasts long, nevertheless I do hope temperatures reaching near +30C return for one or two weekends. In late August or early September such daytime heat is accompanied by cooler nights and brisk mornings which take the edge off heat. The summer is slowly giving way to autumn. Lower temperatures and shorter days are not the only signs of it. Many trees begin to shed their leaves earlier than usually. The same happened last year in August and with hindsight it turned out in such way the nature anticipated a shift in weather from hot summer into gloomy autumn. If this year the same pattern is to repeat, may it also continue into warm late autumn and winter, as it did last year.

No comments: