{"id":2269,"date":"2026-07-03T17:04:17","date_gmt":"2026-07-03T15:04:17","guid":{"rendered":"https:\/\/blog.zhaw.ch\/metenvia\/?p=2269"},"modified":"2026-07-03T17:08:59","modified_gmt":"2026-07-03T15:08:59","slug":"june-heatwave-microclimatic-observations-from-the-winterthur-network","status":"publish","type":"post","link":"https:\/\/blog.zhaw.ch\/metenvia\/2026\/07\/03\/june-heatwave-microclimatic-observations-from-the-winterthur-network\/","title":{"rendered":"June Heatwave: Microclimatic Observations from the Winterthur Network"},"content":{"rendered":"\n

If you stepped outside last week, you didn\u2019t need a thermometer to tell you that summer had arrived. At the end of June, Switzerland experienced a historic heatwave<\/a>, with over 40 meteorological stations across the country recording new temperature records for the month. Maximum daytime temperatures exceeded 38\u00b0C at several locations, and many regions experienced tropical nights, where minimum temperatures remained above 20\u00b0C.
The primary cause of this event was a stable high-pressure system that transported hot, dry air masses from North Africa across Central Europe. Combined with the high solar radiation and long daylight hours characteristic of late June, this led to sustained high thermal load. <\/p>\n\n\n\n

We experienced this thermal load firsthand in our own office in Winterthur. Fortunately, through an ongoing collaboration with the city of Winterthur, we have access to the local temperature measurement network, which allows us to look closely at what our sensors recorded during this heatwave. If you are interested in the data, the historical records are publicly available<\/a> on the Stadt Winterthur open data portal, and you can also view the live, real-time temperatures right now on the Winterthur city temperature network map<\/a> (under the tab \u00abStadtklima\u00bb).

So what did we measure in WInterthur? Let’s have a look:

<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

The figure shows the temperature measurements, recorded every 10 minutes between June 21st at 00:00 and June 28th at 23:59, for three different stations within the Winterthur city network. The orange line represents the Graben station<\/a>, located directly in the city center in an environment dominated by concrete and asphalt. The green line shows the Schulhaus Hegi station<\/a>, situated in a residential neighborhood with a higher proportion of green spaces. The blue line represents our remote station at the top of the Eschenberg tower<\/a>; positioned above a forested hill at the highest point in the area, this station measures open-air temperatures that are less affected by ground-level heating and cooling. For reference, dashed lines are included at 20\u00b0C and 35\u00b0C.<\/p>\n\n\n\n

Several non-surprising observations can be made from this plot:<\/p>\n\n\n\n