First three months of 2015 show fewest U.S. tornadoes in three decades
Written by Thomas Richard, examiner.com
Yesterday, the Daily Caller reported that the Weather Channel’s chief meteorologist, Greg Forbes, said the number of tornadoes so far this year has been 27, with “only four tornado watches” issued, and zero touching ground in March, the fewest in nearly three decades.
Unlike hurricane season, there is no official start or end date for tornado season. What is remarkable is that “this is the slowest start to the year, tornado-wise, since the 21 tornadoes were recorded through March 12, 2003.”
February was also statistically important as there were only two tornadoes reported during the entire month. “According to statistics kept by Dr. Forbes, only three other Februaries since 1950 saw two or fewer tornadoes in the U.S.: 2010 (1), 2002 (2) and 1964 (2).”
Greg Carbin, a warning coordination meteorologist at NOAA‘s Storm Prediction Center (SPC), said “only four tornado watches were issued by the SPC for January and February combined.” The last time there were this few tornadoes was in 1985, nearly 30 years ago, when only two tornado watches were required.
So far this year, the SPC has gone 51 continuous days without issuing “either a tornado or severe thunderstorm watch through February 25. This was the longest such watch-less streak since late 1986,” according to Carbin.
The cause of this tornado drought is the “bitter cold, snow and ice” that began in early 2015, mainly affecting the Eastern portion of the United States. Coupled with the lack of moisture moving up from the Gulf Coast, and an altered Jet Stream, you have the perfect ingredients for little to no tornadoes.
“The rise in mainly weak tornadoes detected in recent decades due to meteorological and technical advancements such as Doppler radar and social media, as well as larger spotter networks, the three-year period from 2012-2014 was considered the least active three-year period on record dating to 1953,” according to Carbin.
In other words, as technology improves and remote areas become more populated, people are utilizing their phone’s cameras and posting videos to social media sites like YouTube and FaceBook, as well as media outlets.
Tornadoes haven’t necessarily increased in frequency, but rather denser populations, tornado chasers, and advanced technology are documenting smaller, weaker tornadoes that would have gone unnoticed (and thereby uncounted) in previous years.
As for the rest of the spring and summer, meteorologists “cannot predict how the rest of the year will shape up, tornado-wise. The final tallies depend on how persistent the western ridge-eastern trough pattern described above remains into the spring, as we head toward the April-June U.S. tornado maximum.”
Carbin said in a statement that, “We are in uncharted territory with respect to lack of severe weather. This has never happened in the record of [Storm Prediction Center] watches dating back to 1970.”
“Once the jet-stream pattern changes, allowing warmer, more humid air into the central, southern and eastern U.S. in spring, severe thunderstorms will follow suit,” The Weather Channel reported.
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