12/14/21 Tuesday 8:30 am
I have been critical of the Euro the last couple of days. It is showing me something I haven’t seen before. I have simply been spending too much time looking at the precipitation spreads. The model has been consistent for the most part. It is showing a dramatic uptick in precipitation just east of Durango. Call it a Bayfield bullseye if you want. It is a little more refined this morning than it was yesterday. I can’t continue to completely discount its output.
What if it is real? It would mean that the storm would hit Durango then start rapidly intensifying as it moved east. It would mean stronger winds, possible thunder and lightning, and the potential for heavy snow.
But, based on the terrain between Durango and Bayfield, it seems unlikely that a 500-foot increase in elevation would create enough lift to produce such anomalous precipitation amounts in Bayfield proper. It is also highly unlikely that more precipitation would fall in Pagosa than Wolf Creek and the Euro is the only model showing that. It might be that the model is right about the strengthening but wrong about where it occurs.
You also have to take into consideration that the front and associated area of low pressure is currently near Merced, California. It has to travel nearly 700 miles over the next 20 to 24 hours. Here is the latest surface map.
Like any good weather nerd, I was reading the area forecast discussion from the offices that are in the middle of the storm right now. One of those offices was discussing the storm exiting their region and “closing off near the four corners”. When a low “closes off”, it usually rapidly intensifies and it moves very slowly, if at all.
Several days ago I mentioned the storm intensifying when I was discussing the difference between a negatively tilted trough and a positively tilted trough. I also mentioned that storms usually slow down while they are intensifying. I didn’t understand why the models were moving the storm through so quickly. I still don’t.
So given what I was reading, and what the Euro is showing, I think everyone from the Utah border to Pagosa needs to pay attention to this situation. The Euro may be right about the rapid intensification starting just past Durango. Or, it could just as easily start east of Cortez, or not until Pagosa. Hopefully, throughout the day we will get a better read on this. A lot can happen to a storm over 700 miles.
For now, I am still planning on rain and rain/snow mix being the dominant precipitation type for the lower elevations overnight, then a brief switch over to all snow in the morning.
The NWS in Grand Junction said they issued the low elevation winter weather advisory with the thought process that they could upgrade the advisory to a warning later if the situation warranted it. If the system closes off, slows down, and intensifies, we will have a completely different situation on our hands in regards to the snow totals.
Here are the latest model runs.
Latest NAM 3km
Here is the same model from my alternate service provider. This shows more details for Wolf Creek
My next update will be out around 1 pm. Thanks for following and supporting the site!