10:30pm Sunday update:
Southerly flow is doing well to bring some snow showers to the high elevations of the Wasatch right now. Hard to tell via webcams but it looks like at least light snow is falling in the Cottonwoods. Sundance can do well in this pattern, so I’ll be interested to see how much they pick up by tomorrow morning. Southern Utah mountains have seen snow for much of the day with a few inches accumulation. It’s not an impressive system, but hopefully we get surprised again. WSF
A splitting system will push across the Great Basin tonight thru tomorrow (Monday). This will bring snow to the mountains of Utah with the heaviest accumulations in central and southern portions of the state.
We always knew this storm was going to split. Unfortunately, it seems to be doing so even earlier than we feared. Which means that it will severely limit snowfall amounts. Snow will begin in the mountains of Utah tonight and continue off and on thru Monday night. With the heaviest snow concentrating on Southern and Central Utah mountains. The NAM is still relatively optimistic, depicting 8″ for the upper Cottonwoods by Tuesday morning:
However, this may be a bit over-done, as previous runs weren’t so optimistic. Southern and Central Utah is where the best snow will be with 6-12″ likely for the high elevation there:
You can see the ‘pinks’ indicating good accumulations. The Wasatch, unfortunately, is not exactly favored in this type of splitting storm. Therefore, I think Northern Utah mountains will generally be in the 3-6″ range, with perhaps lower amounts toward the Idaho border. The Cottonwoods could do a bit better (5-10″), but still, nothing major. My advice would be to set expectations low for this storm. Who knows? As long as there is storm energy in the neighborhood, there’s always a chance for us to get surprised like we were last week.
After this storm moves out by Tuesday morning, the forecast gets exceptionally difficult. The GFS and GEM show moisture advecting into northern Utah later this week, with a possible trough dropping in out of the north for the weekend. This would be a decent pattern for snowfall. However, the generally more reliable Euro is much weaker with this advection and keeps it to our north, keeping northern Utah mostly dry through the week. The Euro also doesn’t have much of a trough for next weekend. The models are certainly at odds with each other. My guess is that they will find some type of common ground by this time tomorrow at the latest.
Some preliminary signs that this is now the strongest El Nino on record. Here is one calculation of the key 3.4 region SST anomalies:
It shows that current SSTs are about to go off the chart. Stronger than any event in recorded history. This isn’t the official calculation — the CPC will release the official weekly data tomorrow, but we could be looking at historic values. This would seem to indicate that California has a good chance for a very wet winter, which would certainly help to alleviate drought conditions. Latest CFS continues to show the Golden State getting clobbered this winter (Dec-Feb):
As I’ve said previously, Utah doesn’t have nearly as strong of a signal. We can only hope that all the action to our west spills over to our neck of the woods. It will definitely be fun to watch!