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Monthly Archives: March 2024
Has our plant hardiness zone changed?
If you are involved with gardening, you probably are aware of the Plant Hardiness Zone Map, or PHZM, often listed on seed packets. The U.S. Department of Agriculture developed the zones and first published them in 1960. The USDA updated them in 2012 and more recently in November 2023.
A hardiness zone provides information on the type of plants capable of surviving certain climatic conditions. The designations are based on the “average annual extreme minimum temperature” at a given location during a particular 30-year period. The climate zones are determined from temperature records kept by National Atmospheric and Oceanic Administration. Continue reading
How is visibility distance evaluated for a weather map?
The weather observing stations of the National Weather Service operate in fully automatic mode and have sensors that measure visibility.
These instruments sense the forward scattering characteristics of light to measure the extinction coefficient of a high intensity beam directed at a volume of air close to the sensor. This provides an accurate measurement over a range of visibilities. The use of light within the visible spectrum also allows the sensor to simulate human perception of visibility. Continue reading
You thought Wisconsin’s winter was warm? Wait till summer
Changes in the weather patterns that brought record-breaking warm temperatures to the Madison area this winter might also mean that a warmer-than-usual summer lies ahead.
There’s a fair chance that temperatures could rise above normal in June, July and August, and even into early fall, climate scientists say. Continue reading
How did this mild winter compare to previous such years?
We are now past the end of the meteorological winter, which consists of the months of December, January and February.
This season has been a remarkably mild one for most of its duration. With the exception of a week of desperate cold in mid-January, there was hardly any cold air to speak of in southern Wisconsin all winter. In fact, Madison was 9.5 degrees above normal for December, 3.5 degrees above normal for January (reduced because of the cold snap Jan. 14-21, during which the temperature was 14 degrees below normal!) and 11 degrees above normal for February. Continue reading
