Apart from the wind damage, Tuesday's rain was nice. However, this rain was not an end-all rain by any means. The 1-2 inches most areas got will green the grass a bit and stave off major concern about a summer drought. But unless it rains substantially again in the next week or two, our region will be wanting for rain again. Since the rainy period began in 1993, most of us have become accustomed to heavy rainfall during May, June and July. It rains an inch or two and then, a couple of days later, another inch or two.
There is probably no weather element so poorly understood as humidity. Actually, we understand humidity when we feel sticky. But most people do not understand how humidity is quantified. Humidity is actually "relative humidity," which means it is relative to temperature. What we quantify as "humidity" is not actually the percentage of water vapor in the atmosphere (absolute humidity) because that number is always so ridiculously low (.01%) so as to be useless to the general public.
Have you ever noticed that thunderstorms often appear to weaken or change direction just before hitting your area? This illusion is common everywhere, but in most cases, it is just an illusion. One reason for this is parallax. This is the illusion that something is coming straight for you when it is actually moving almost, but not quite, straight toward you. It appears to change direction to one side or another as it passes by when, in reality, it was never headed right at you to begin with.
There is a jet stream pattern setting up that may have lasting impacts on our weather. The polar jet stream is in the process of forming into a high-amplitude, very wavy pattern around the world. These patterns are most likely in spring and usually result in stagnant weather. It appears there will be about six main lobes in which the jet stream will go rather far south, delivering cold and wet weather to these areas. In between, there will be six areas in which the jet will go far to the north, allowing for sunny, warm conditions.
The temperature sensor at the official gauge for Fargo-Moorhead at Hector International Airport malfunctioned late last week, indicating a temperature of 50 degrees late Thursday night. The temperature was actually 35 degrees at the time. Temperatures in the 50s in Fargo-Moorhead during January are rare, obviously, but not entirely unknown. Ten of the 31 days in January sport a record high temperature in the 50s, so it does happen occasionally. The years 2012, 2002, 1981, 1942, 1931, 1908 and 1900 all have at least one daily record in the 50s.
Whenever we get a spell of snow-melting weather in January, a few people always ask if this is "The January Thaw." There is no such thing as "The January Thaw." There are, however, usually at least a couple of days of thawing temperatures at some point in any winter month in our region. This is due to the natural up-and-down, highly variable nature of our climate, particularly in winter.
The frigid weather that persisted most of the first two weeks of this month has prompted a lot of people to ask why the weather has been so unusually cold. It hasn't, actually. Although temperatures have been consistently below average so far in 2017, none of this weather has been unusually cold. No temperature records have been broken. In fact, the average lowest temperature of a winter season is 27 below and we have not been that cold yet this winter.
The blowing snow Thursday created another round of beautiful sun dogs in the sky, prompting a number of questions about how and why they form. Sun dogs are caused by hexagonal ice crystals suspended in the air that refract sunlight. This usually happens for one of three reasons.
On Christmas Day, a somewhat rare ice storm left three-quarters of an inch of ice on most of our area. Three weeks have passed, and many of our sidewalks are still covered in three-quarters of an inch of ice.
The last time the temperature in Fargo-Moorhead officially reached 30 below was Jan. 2, 2010, when the low temperature of the day was 33 degrees below zero. Six years is a long time, historically, to have gone without any minus 30 temperatures. The year, 2010, was the third consecutive winter with a temperature of at least 30 below, suggesting the current six-year run is more of a statistical blip than a trend.