The models are starting to paint a picture of some precipitation, the bulk of which should fall later in Thursday or perhaps overnight into Friday into mid-morning Friday. Needless to say still some uncertainty. I have not seen the models noticeably delay the not storm (if this is confusing read my previous post). With this particular storm track I don’t know if the models are generally too fast with the movement. All I can tell you is that so far it has not been delayed a bunch. The storm itself is off the southern California coast. Immediately to its northwest is a closed low with a shortwave trough. The idea is that the front is going to come onshore a continuing southeast skirting the Mexico border while advecting moisture into our area about the time it hits Arizona. Confidence is low regarding the timing that all this takes place. So the Euro model, the model that had virtually nothing yesterday is the most aggressive with the precipitation. The caveat is the Euro shows a period of heavy rain Friday morning but I can only guess that the dividing line is at 6,500′. The GFS clearly shows the snow level at 6,500′ but has less precipitation. It is time to pack up the Canadian model until the next storm, or not storm. We rarely use that for anything but to help establish a trend because it is very low resolution. We can, however unpack our High Resolution model since the event falls within its 60 hour limit.
So we will start with the GFS, the GFS does have snow starting a little earlier especially in the higher mountains and from Purgatory northward. It actually shows some light snow late morning or early afternoon. I will withhold judgement on that until tomorrow when I wake up and see the overnight model runs.
It is very difficult to see but the GFS shows 2″ at the airport. It has been trying to something in the southeast part of La Plata County, by I think that is a model resolution error. BTW the samething with Wolf Creek, GFS almost always samples the elevation at Wolf Creek incorrectly. The WRF model and to a lesser extent the EURO always do better for Wolf Creek.
I gave you my caveat there. I will be very interested to see what happens overnight, I have a feeling it will back off a bit.It shows 4″ at the airport. I like the idea that the band of heavier accumulation goes from 160 north to Purgatory. We will see, I still don’t understand the rain yet.
WRF this model updates very quickly and paints the best pictures from the model runs closest to the onset of precipitation. In other words, it may be too early to take this seriously. That being said, it shows 3 at the airport 7 at Wolf Creek and some spikes in the La Platas and Needles.
I will have time to post graphics in the morning but probably not analysis, that will come late morning early afternoon.