June 1, 1008:
May was a terrible severe weather month for much of the United States. Numerous deaths, tremendous damage, and many, many, tornadoes. The Windsor tornado on May 23rd was responsible for $147 million in damage and one fatality. However, most of the severe weather has been confined to our east. Will that change in June ? Right now, it is tough to say. June is normally Colorado's most active severe weather month. Over 40% of all the tornadoes that occur in Colorado, occur during the month of June. One of the most notable tornadoes in Colorado history. On June 6th, 1990, an F-3 tornado destroyed much of the town of Limon. This event peaked my interest in Meteorology. I had just completed my Freshman year of high school, and this weather event was responsible for pushing me into the field of Meteorology. For all of you weather geeks out there, I have supplied a detailed link to the mechanics of that severe weather day, in eastern Colorado: http://ams.allenpress.com/archive/1520-0434/9/1/pdf/i1520-0434-9-1-45.pdf
Large hail, damaging winds, flash flooding, and dangerous lightning are all part of a normal June in Colorado. However, this year has been a little different. The "dryline" ( the boundary between hot and dry air to the west and warm, moist air to the east ) has been moving away from the mountains during the early part of the day. By afternoon, it has been located along or just east of HWY 71. Thus, what little severe weather we have had this season, has been confined to the far Eastern Plains. This has to do with the ongoing drought conditions, across our area. The dry ground can heat up more effectively, and each day it doesn't receive rain, it can heat up even quicker the next day. Most of the time, our moisture level is pretty shallow around here. Meaning, the moisture doesn't extend very high up into the atmosphere. With the rapid heating during the morning, the atmosphere churns itself up and sends the dryline east. The wind is a big player in this process. Once our wind turns to the southwest, west, or northwest, that means the dryline has been sent east, and our rain chances diminish considerably.
While it is tough to say if this pattern will continue into June, the odds are in favor of it continuing. Most of our long range computer models keep the jet stream to our north, and the best low level moisture ( fuel for thunderstorms) to our east. While we will still see severe weather days, they may be limited this year. Simply put, I think we will be talking more about fire danger and drought, than hail and tornadoes. Nevertheless you always need to have a severe weather plan that you can put into effect, in case severe weather threatens your area.
Chief Meteorologist Brian Bledsoe