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SKYWARN Meeting
The next SKYWARN meeting is 17-Nov @ 7:00 PM, the third Tuesday of the month.
October Snow
From USA Today
The first snow fell overnight on 10-Oct. Just enough ground cover to say "Yep, it snowed". On 12-Oct, record snow falls were reported at MSP Airport at 2.5 inches and Rochester Airport at 2.6 inches. Rochester added another 0.6" on 14-Oct. October snow is fairly common. Historical records indicate MSP has a measurable snowfall every three years, on average.
WX Station History
From Minnesota WeatherTalk
The first automated weather station may have been deployed by a German U-boat in 1943. It was discovered on the Canadian Island of Killiniq along the Labrador Sea in 1981. It provided basic meteorlogical data for a couple of days before the transmission frequency was jammed for the balance of the war.
Thanksgiving Snow
From Minnesota WeatherTalk
Looking forward to Thanksgiving, records for MSP show there is snow cover about 50 percent of the time. Snowfall over the 4-day weekend occurs 57 percent of the time. Daytime high temperatures on Thanksgiving Day span from a high of 62 degrees F in 1914 to ja low of 4 degrees F in 1930.
Water Does NOT Freeze at 32F
From USA Today
Most of us in school learned that 32°F is the freezing point of water. However, it is more proper to say that 32°F is the melting point of ice. While ice always melts at 32°F, liquid water can, but does not have to, freeze at 32°F. In fact, if you want to get into the chemical technicalities, microscopic ice crystals start to form in liquid water when the temperature drops below 39.2°F.
When we typically think of water freezing into ice, we might think of an ice cube tray in the freezer. Nucleation is the main reason why ice cubes begin to form at or slightly below 32°F. Ice crystals can attach themselves to surfaces (such as the tray) or to impurities within the water. Remove the impurities (distilled water) and the water will have to cool more in order for freezing to begin. If you could levitate water out of the tray (or suspend it as tiny cloud droplets in the atmosphere) and you’ll see that the required temperature for freezing is even lower. With sufficiently pure cloud droplets, they can remain liquid to temperatures as low as -40°F. This is why, you can have subfreezing temperatures, fog (liquid water droplets) in the air, as well as ice forming on the railing. The fog droplets are actually supercooled (below 32°F) and freeze upon contact with the railing as it provides a surface upon which ice crystals can form.
November Moon
From Earth Sky
A full moon will occur on 02-Nov. In the northern hemisphere, the November full moon is called the Frosty or Beaver Moon. The November full moon – like the full moon at any season – shines from sundown to sunup, and climbs to its highest point in the sky around midnight. Because the full moon occurs when the moon is most directly opposite the sun for the month, the full moon’s path across the sky mimics that of the sun six months from now. In both the northern and southern hemispheres, the November full moon rises in the east-northeast and sets in the west-northwest – just as the sun does in May. In the northern hemisphere, the Frosty Moon will soar up high, like the springtime sun.
Freezing Plants
From USA Today
Plants won't freeze if the air temperature is above freezing (32F). What about the wind chill temperature? Strong winds can actually help keep plants and vegetation from freezing on cool nights, by stirring up layers of air and bringing warmer layers down to the surface.
WX Glossary
With the summer ending, many outdoor activities end. Curling up in front of the fireplace with a good book provides an excellent time to lbrush up on sever weather terms and definitions. A glossary of weather-related terms is available. Use the glossary to achieve some level of standardization in the definitions of the terms that are used. The idea is to allow smooth and effective communication between storm spotters and forecasters.
Climatology
From NOAA
The best resource for historical snow data is the
National Climatic Data Center’s Snow Climatology site. You can get a variety of historical snowfall information in Chicago by clicking through that site.
Oxygen Content
From USA Today
There is a difference in the amount of oxygen in the air in the winter compared to the summer (especially in the Northern Hemisphere). The amount of land (and thus trees and plants) in the Northern Hemisphere produces a summertime minimum amount of CO2 in the atmosphere as well as a O2 maximum (due to photosynthesis). A reversal occurs in the winter, both due to a lack of photosynthesis as well as an uptake in O2 as bacteria decompose organic matter (such as fallen leaves). The change in concentration is not significant enough to have much impact on human health. The lack of moisture in winter air, however, can have an effect on the body. Outside air dries out further as it is brought inside and warmed. Ordinary heaters don’t add moisture. Water from skin, noses, and throats evaporates into the air. To reduce evaporation, use a humidifier and keep it clean. Ideal indoor humidity is between 30 and 50 percent.
Term For The Month
From Minnesota WeatherTalk
Barber
This term originates from weather forecasting on the Great Lakes and is still used by mariners at times today. Most of the time it refers to a severe storm on the Great Lakes or in the Gulf of St Lawrence which produces a lot of frozen spray or ice that sticks to the ships riggings. In its worst form it can be a blizzard in which the wind-borne ice particles almost cut the hair and the skin from a mariner's face. Nasty business.
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