This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.
Issued: Saturday July 8, 2017
By John Ensworth
This feature will run as close to daily as possible in this location on the Longmont Observer.
This article will provide a brief discussion concerning the ‘why’ behind the weather with a focus on severe weather, unusual weather, and snow (especially trying to predict snow depth and its human impact in Longmont).
Discussion:
The big ridge, described yesterday, has rocked just a tad further west and is centered over south-central Utah. Colorado is still sitting on the right side of this ridge. Our fairly faint, slow moving, cool front that is backing in from the northeast, won’t make as much progress south as expected yesterday… so the marginal risk of severe weather (1 on a scale of 1-5) will include Denver and areas south and east of the big city. Longmont is not expected to be at risk of severe weather on Saturday with temperatures at their lowest this week (but still upper 80’s). Our average high for this date is 86F and our average low is 61F. We are not too far above average. Nice!
With the front at its furthest south, and the ridge at its furthest west today, ripples in the jet stream will move out of the northwest (in what is called northwest flow) which might kick off a couple rounds of weak to moderately strong storms in the foothills. These widely scattered storms will move southeast through afternoon and early evening. BySunday, the ridge will be on the move eastward passing over us and drying us out with near 100F temperatures still expected on Monday.
In a look at the longer range: there is a hint that some tropical moisture will make it into Colorado around the end of next week that could spell our first taste of the summer ‘monsoon.’ We need this ridge to move further east so we get a more southeast to south flow over the state. More on that later.
Bio:
John Ensworth works from Longmont as the Principle Investigator for the NASA Science Mission Directorate Earth and space science education product review. He is in his 14th year running this review. He is an astronomer (from the 2nd grade onward) and became a meteorologist (in the 5th grade) when a thunderstorm in Arizona rained on his telescope when the weather service had only forecasted a 10% chance of rain. He has college degrees in physics and astronomy and climatology and a graduate degree in meteorology and earth science. He lectures at the Little Thompson Observatory in Berthoud, the Estes Park Memorial Observatory in Estes Park, and for a number of online universities. He built and runs a backyard observatory near Pace and 17th in northeast Longmont where he has lived for 8 years with his wife, daughter, son, and two cats. Invitations to open house nights at this observatory, LTO, and EPMO will be posted with future discussions when they are scheduled.
Forecasting severe weather and snow amounts via text lead to this column. He began texting friends about the weather right after the September 2013 flood. The readers of this column will, hopefully, keep him honest in what he ‘thought’ he had forecasted for ‘the most recent’ storm.
