Category Archives: Climate
Given our recent weather, and with the pollen season dawning in southern Wisconsin, one may wonder if there actually is a windiest time of year in Madison.
Of course, a windy day can come along just about any time of year (the record gust of 83 mph in Madison occurred in June 1975) but the climatology suggests that March and April are the windiest months of the year with average wind speeds of 11.3 and 11.4 mph, respectively. November through February are not far behind, logging a four-month average of 10.5 mph. Continue reading
The seasons result from the tilt of the Earth and its yearly circling of the Sun. According to the astronomical definition, spring occurs when the Sun’s rays strike the equator at noon at an angle that is directly overhead. This particular time varies from year to year due to variations in the Earth’s orbit about the Sun. In the Northern Hemisphere the Vernal (or spring) Equinox (equi, ‘equal,’ and nox, ‘night’) occurs sometime between March 19 and 23, but often on March 20 or 21. This year astronomical spring arrives on March 20 at around 4:58 P.M. CDT. During the equinoxes all locations on Earth experience 12 hours of daylight and 12 hours of darkness. The Sun rises due East and sets due West. Equinoxes are the only two times a year that Sun only rises due east and sets due west for every location on Earth! After the Spring equinox, the Northern Hemisphere tilts toward the Sun, and we start to get longer, sunnier days.
Spring marks the transition from winter to summer. Meteorologists divide the year into quarters to compare seasonal and monthly statistics from one year to the next. Meteorological spring is defined as March through May and so begins on March 1. We might also define spring as the day on which, if there is precipitation, it is more likely to be in the form of rain than snow. For southern Wisconsin, that occurs later in the month of March. Continue reading
If you are not a student of meteorology, you should rely on your local weather forecasters for a good weather forecast — and southern Wisconsin has some very good local forecasters. It is their job to interpret the various numerical weather prediction models.
Numerical weather prediction models, or NWP, solve a complex set of mathematical equations that are based on the physics that drives how the air moves and how heat and moisture are exchanged throughout the atmosphere. Continue reading
Most of Antarctica is covered by ice.
The ice sheet is over 2 miles thick in places and in some places the ice sheet bottom is almost a mile below sea level. This massive ice covers mountain ranges, and volcanoes exist underneath the sheets. Continue reading
The year began with frigid temperatures across Wisconsin. The average temperatures for the first seven days of January were well below normal across southern Wisconsin with most areas at least 15 degrees below normal.
The end of 2018 saw temperatures several degrees warmer than normal, including a record high temperature of 50 F on Dec. 27, tying a record high for the date, last set in 2003, and previously set in 1936 and 1946. Continue reading