In Brief:

We have two more days of summer thunderstorms with a Marginal Risk painted for the area Thursday PM. The weekend will be hot and dry – getting close to 100F again. Next week a stout cold front will invade Tuesday-ish and we may only see highs in the 70’sF mid to late week. Woohoo!

Forecast Discussion:

Figure 1 shows some moisture up the spine of the Rockies and Pacific moisture coming in from the west with surface moisture being pushed back to the west from the big thunderstorm complex that drifted to the southeast through the Midwest last night. There is still moisture around Thursday and with the short wave fairly close to the state to the west (Figure 2) – we’ll see more storms.

The SPC has painted us with a Marginal Risk again Thursday with hail and high winds being most likely (Figure 3). (It mostly skipped Longmont on Wednesday -but some Coloradans got hit.)

The Longer Range Forecast:

Figure 4 shows that serious heat and bone dry conditions will dominate the state this weekend. A deep trough is shaping up in the models that will blast the center of the nation with a lot of cold air. We “may” only see lower 70’sF after mid-week (not reflected in the weatherunderground model shown). Here’s to hoping!

Figure 1: the water vapor satellite image (browns/reds are dry air, whites and light grey is moist air, purple/blue is ice and high cloud tops). From the the Weather Channel from Wednesday evening.
Figure 2: The 500mb forecast upper air analysis for Thursday AM. Pink dot is Longmont. Red lines are troughs, blue lines are ridges.
Figure 3: The severe storm weather forecast for the U.S. from the Storm Predication Center in Norman, OK. Made Wednesday for Thursday.
Figure 4: the graphical forecast for the next 10 days for Longmont, CO from
Previous articleMosquito spraying alert for Thursday, Aug. 22
Next articleBoulder County Sheriff’s Office Citizens’ Academy accepting applications
John Ensworth works from Longmont as the Principle Investigator for the NASA Science Mission Directorate Earth and space science education product review through the IGES (The Institute for Global Environmental Strategies – . 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.

Leave a Reply