Forecast Discussion:

Our system has side down into Mexico with cold air off into the Gulf of Mexico (Figure 1 and Figure 2).  For today, the trough is still sliding very slowly eastward as a big ridge nudges in from the west (Figure 3).  That spells big warm up soon…

Figure 1: The current surface map from Tuesday PM and the Weather Channel.
Figure 2: The current surface temperatures from Tuesday PM. Remarkable cold ‘circled’ in red.
Figure 3: The 500mb forecast upper air analysis for Wednesday AM. Pink dot is Longmont. Red lines are troughs, blue lines are ridges.Figure 3: The 500mb forecast upper air analysis for Wednesday AM. Pink dot is Longmont. Red lines are troughs, blue lines are ridges.

The longer range forecast:

By the end of the week, the ridge will be in place (even if there is a southern-branch trough/cut-off low over TX/LA) – Figure 4.  We warm quickly as that cold air leaves and is replaced by compressional heating/down slope flow over Colorado (Figure 5).  We may top 60F for highs near Longmont Friday.  The weekend storm still looks like – not much.  A new storm is lurking 10 days out.  We have seen most of these fade out to nothing as the actual day arrives.  I’m not sharpening my snow shovel yet. The dryness continues.

Figure 4: The 500mb forecast upper air analysis for Friday AM. Pink dot is Longmont. Red lines are troughs, blue lines are ridges.
Figure 5: the graphical forecast for the next 10 days forecast for Longmont, CO from weatherunderground.com
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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 – www.strategies.org) . 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.

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