Colorado is known for extreme weather, but what one city in southern Colorado saw on Friday might raise some eyebrows, even for Colorado’s lofty meteorological standards.
Alamosa saw a high of 92 degrees Friday, breaking its old daily record of 91 degrees, which was set in 2003. That record high came just a few hours after Alamosa tied its daily record low temperature of 37 degrees.
At 4:45 a.m. Friday, Alamosa dropped to 37 degrees, a temperature that under the right circumstances can lead to patchy frost. Eleven hours and two minutes later, though, Alamosa was up to 92 degrees. That meant Alamosa saw a 55-degree temperature swing in less than half a day.
The gap between record high and record low largely can be attributed to two things: the ongoing drought that’s plaguing southern Colorado and diurnal temperature cycles that allow temperatures to climb and fall rapidly in an especially dry air mass.
So far this year, Alamosa has received only about an inch of rain, about one-third of what the city averages in the same period. A subpar snowpack season for southern Colorado (and one that melted quicker than normal) meant that soil conditions in this part of the state are especially dry. That’s also boosting fire danger.
Drier air allows temperatures to rise and fall more efficiently. For example, Denver’s average high this time of the year is 89 degrees, with an average low of 59 degrees — a 30-degree gap. A much more humid and coastal location such as New York, for example, has an average high of only 84 degrees but an average low of 69. That’s only a 15-degree gap, and it’s almost entirely the result of the added moisture in East Coast air.
Alamosa is a dry place to begin with, even for Colorado standards. With only 7.31 inches of rain a year, Alamosa is considered to be in a high desert climate. But with an ongoing drought and other conditions making the city especially dry right now, temperatures are climbing and falling more quickly than usual.
So far this month (through Friday), Alamosa is averaging a high of 87 degrees and a low of 40 degrees. That’s a 47-degree average monthly temperature spread, which is unusually wide, even for a dry place such as the San Luis Valley. Alamosa’s average high for July 10 is 83 degrees, with an average low of 47; a more manageable 36-degree spread. But the drought, in particular, appears to be exacerbating daily highs and lows in Alamosa.
The National Weather Service office in Pueblo also put out a detailed report on Alamosa’s simultaneous daily record high and low from Friday, if you would like to learn more.
Source: Read Full Article