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>40 years of hourly weather data with history+
Access historical weather information for Ann Arbor with history+. Available worldwide and independent from weather stations. Download consistent and gap-free hourly data for Ann Arbor as CSV. You can test data access for Basel freely.
Risk assessment diagrams
- Cold and warm events: Probability of temperatures below or above a certain temperature threshold for a given time. Can be used to evaluate frost (or heat) risks. The first diagram shows the likelihood of the event in a day or in a week. You can approximate your personal tolerable risk with the second diagram. If your tolerable risk for a frost event is 20%, you should schedule sowing in late April for example. If you can accept 50% frost likelihood in favour of earlier sowing, the second week of March may be more suitable. The third diagram shows the occurrences of warm and cold events in the last 40 years for each year.
- Precipitation: This diagram evaluates precipitation amounts above a certain threshold in a week. As with cold and warm events, you can estimate heavy precipitation events and schedule activities accordingly.
- Water capacity: Estimated probability of remaining soil water amount. Select the maximum amount of soil water capacity depending on your soil and crop type. Higher soil water capacities are better indicators for extremely dry seasons. Yellow, orange and red bars indicate almost depleted soil water.
- Cloud cover: Cloud free hours per day. The first diagram shows the probabilistic distribution of cloud cover below a certain threshold. P80 and P20 indicate the second best and second worst out of ten events: so there is an 60% likelihood of 5-7 hours of cloud cover below 15% in Basel in early October for a given day. The statistically most cloud-free days would occur in Basel during mid August. The lower diagrams shows the actual occurrence of cloud free hours in the last 40 years.