John was born in Baton Rouge, LA, and grew up near Birmingham, Alabama. As a teenager, his family moved to Madison, Wisconsin, and later to a small town in northeast Iowa. John traces his early interest in weather to the difference in climate between Alabama and Wisconsin. He is a graduate of Iowa State University with a degree in meteorology. Like any meteorologist, John is intrigued by extremes of weather, especially arctic air outbreaks and winter storms. John has been known to say he prefers his summers to be hot but in winter, he prefers the cold. When away from work, John enjoys long-distance running and reading. John has been a meteorologist at WDAY since May of 1985.
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It may be the middle of summer here, but it is the middle of winter in the southern hemisphere. Temperatures on the East Antarctica Plateau, a giant ice shelf with an average elevation of 11,000 feet, are routinely in the -90s and -100s this time of year. The all-time low instrument recording at a regular weather station in Antarctica is -128.6 degrees Fahrenheit recorded at the Russian station, Vostok, in July of 1983. However, recent infrared measurements from satellites have estimated surface temperatures as low as -135 degrees.
There are good rain gauges and there are bad rain gauges. If you want an accurate measurement of much rain has fallen on your plot of land, you need a good rain gauge. Most of the inexpensive rain gauges available for sale at hardware stores and big box stores are not going to give you a good measurement.
It seems simple enough to hold a thermometer out in the sun in order to get the temperature "in the sun." But this idea is all wrong. Air isn't heated up very much by sunlight; the rays pass right through. Air warms up in sunlight mainly because the sun's rays heat the ground and that heat then rises up into the air via conduction and convection. Think of how hot a metal car hood gets in the sun. A metal thermometer bulb in the sun will heat up dramatically past the ambient air temperature because it is a solid object and is warmed directly by the sun's rays.
Most of us have seen those mysterious, silent flashes of light from an almost indeterminate direction, seen only at night. Most people call it heat lightning, but there really is no such thing. That is to say, what we call heat lightning is not actually a different sort of lightning. Rather, it is the flashes of regular lightning being reflected off clouds at night that gives us those eerie, silent flashes. It is soundless because it comes from so far away that the sound waves are dampened before reaching our ears.
The shrinking of the summertime Arctic ice cap in recent decades has left me wondering when the last time the Arctic was ice free. It turns out this is a hard question to answer due to the fact that Arctic sea ice undergoes a little melting every summer from top (weather) and bottom (unfrozen ocean) which leaves a poor record.
If you get your current weather information in the morning, you should know that the morning relative humidity is not a useful indicator of how humid the weather will be today. In fact, the relative humidity is fairly useless as an indication of humidity discomfort because it tells us not the percentage of humidity, but the percentage of water vapor saturation.
We live in a windy place. The Great Plains region, in general, is windy because there is very little surface terrain to slow the wind down. Also, here in the Northern Plains, the Polar Jet Stream is usually nearby, so we have a near-constant barrage of varying low and high pressure systems which keeps the air pressure in a state of flux.
Probably since the end of the last glaciation 12,000 years ago, the weather has managed to get humid here in the northern Plains at least a few days each summer.
Perceptions can be misleading. An example of this is the fact that humid air is light compared to air with low humidity.
The next four to five weeks are typically the hottest of the year in our region, so air conditioners will be running a lot of the time, which is expensive. Fortunately, our summers are relatively short. People in Florida, Texas and Arizona pay much more per year to keep their homes cool in summer than we do to heat our homes in winter.