Forecast Discussion:

Things are really quiet and becoming mild again, so I won’t take too much of your time today. The great folks at posted an interpolated graphic of actual snowfall from our most recent storm.  Impressive mountain snow amounts were seen north of I70 (Figure 1).  Figure 2 shows the surface map for midday today (Wednesday) and Colorado is sitting high and dry under high pressure.  Nothing notable but a gentle warm up.


Figure 1: Interpolated Observed Snowfall from yesterday’s storm from the folks at Pink dot = Longmont.
Figure 2: NCEP surface analysis forecast for Wednesday midday. Pink dot = Longmont.

In the Longer Range:

Figure 3 shows the jet stream pattern for Thursday morning and we are on the warm side of the jet with warm southwest winds sending us into the upper 70’s.

Our next storm, Figure 4, comes Saturday afternoon when an approaching trough puts a jet maximum over Colorado (higher speed winds in the high speed winds) that can kick off some afternoon and early evening showers. Figure 5, though, from the GFS, doesn’t show any measurable rainfall in our part of the state- at all – at this time.

Figure 3: 500mb upper air forecast map from the GFS for Thursday morning. Troughs= red line, ridges = blue.
Figure 4: 500mb upper air forecast map from the GFS for Saturday morning. Troughs= red line, ridges = blue.
Figure 5: GFS accumulated precipitation Tue PM to Sun PM. Pink dot = Longmont.
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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.