The last day of July was the hottest

July this year showed its entire spectrum from midsummer to cool, there were also stormy phases. The Azores high occasionally stretched a wedge to Central Europe, often spared northern Germany, where the low pressure foothills had an easier time.

Hohenpeißenberg - The first two days of July were warm in summer on the Hohen Peißenberg. On both days there were thunderstorms with hail and brief heavy precipitation. The first decade was summery and rich in sunshine - the Azores high favored the south.

But during the second decade, summer also weakened in the foothills of the Alps. The maximum daily temperatures on the Hohen Peißenberg were below 20 degrees Celsius on seven days, of which even below 15 degrees on two days. From July 15th to 17th, it cooled down after a hailstorm, so that on the 16th only a daily maximum of 12.9 degrees Celsius was reached. Continuous rain followed: On July 15 and 16, 65 liters per square meter of precipitation fell, i.e. 40 percent of the average amount of rain expected for the whole of July.

The third decade was the warmest, but was associated with daily rainfall until July 28th. There were thunderstorms on five days, three of them with hail precipitation. At the end of the month, the influence of high pressure prevailed throughout Germany. A very short but intense heat wave could build up. In southwest Germany, temperatures rose to 38 degrees Celsius. On the 31st, a hot day (maxima over 30 degrees Celsius) was just missed on the Hohen Peißenberg, as was a tropical night (minima over 20 degrees Celsius) with 19.1 degrees.

Overall, July was a few tenths of a degree too cool across Germany if you look at the 30-year comparison period from 1981 to 2010. If, on the other hand, you take the internationally valid reference period from 1961 to 1990, it was 0.8 degrees too warm. On the Hohen Peißenberg we take the mean values ​​of the 30 years from 1961 to 1990 as a basis and can state for July: With a monthly mean temperature of 17.0 degrees Celsius, it was exactly two degrees too warm. It was actually the 14th month in a row that was too warm.

In the whole of Bavaria, on the other hand, it was only 1.4 degrees too warm on average - it was simply more summer on the edge of the Alps, because the heat of southern Europe spilled over the Alps for a time, the cool western winds could only affect us for the second decade.

So we were able to achieve eight summer days (maxima over 25 degrees Celsius) on the Hohen Peißenberg. On 20 days it was warmer than 20 degrees. The monthly maximum was measured on July 31 at 29.1 degrees. The lowest temperature on July 7th was 8.5 degrees.

The analysis of the precipitation distribution is quite different. In large parts of Germany it was far too dry; nationwide, only 66 percent of the amount expected for many years fell. Parts of Franconia and Saxony also received less than ten liters per square meter of precipitation.

Quite different in the south. On the Hohen Peißenberg, there was 170 liters of precipitation per square meter, 11 percent more than would have been expected over many years. There was measurable precipitation on 15 days, of which over ten liters per square meter on five days and even over 20 liters on four days. The highest daily total in Germany reached Murnau on July 2nd with 97 liters per square meter. The sun shone for 278 hours, which is 21 percent above the average. In 15 days it seemed longer than ten hours. The highest wind peak was on July 15th. 61 km / h.

Siegmar Lorenz

Weather observer Dipl.-Ing. (FA)

in the observatory on the

Hohen Peißenberg