Friday AM update:
No update needed. Just want to say everything discussed yesterday is still on track. Should commence snowing throughout the high Wasatch shortly with rain showers in the valleys.
Quick Thursday PM update:
Everything still on track! Snow and valley rain will start in the Wasatch tomorrow morning and peak in intensity during the evening hours. Areas south of I-80 should get hit hardest, especially the Uintas, where a foot of snow is possible above 9,000 ft. For the Wasatch, we’re looking at 6+ inches above 9,000 ft with an inch or two possible down to 8K feet tomorrow night. Decent rainfall possible for the valleys of the Wasatch Front as well. North of I-80, amounts will be on the light side with only a few inches. Our first Winter Weather Advisory of the year is in effect for all Central and Southern Mountains of Utah and the Uintas. Get stoked!
Thursday (October 11) AM update:
Another quick update this morning. Low now looks like it will track a bit farther north which will be great for the Wasatch. The majority of precip will still fall in Central and Southern Utah and eventually the Uintas, but the Wasatch will still see fairly substantial precip as well. Snow levels looks to stay fairly high at around 9,000 ft, but above that, we could see easily 6 inches+ of wet snow. The timing looks to be on Friday afternoon/evening for Northern Utah. Rain/snow will fill into southern Utah today and tonight before moving north through tomorrow morning. The slow movement will allow for fairly significant rain and even snow amounts for favored areas. Will this be the start of a permanent snowpack or just a teaser? We would guess the latter even if we get 6 inches or more as the ground is still warm and after this we’ll see dry and seasonable temperatures for the foreseeable future. Any snow that falls will likely melt off except for the shadiest spots.
After this weekend, a zonal flow will impact the Pac northwest and far northern Rockies. GFS still shows a chance for us to get clipped early next week but don’t expect much more than clouds and breezes at this time. We’ll let you know when the next system shows up in the computer models. Stay tuned . . .
Previous . . .
Tuesday PM update:
Taking a quick break from vacation to look at the models and long range forecasts and share what we’re seeing with you, our loyal readers. The long-advertised cutoff low will start meandering inland over the next couple days heading from Southern California northeast toward southern Utah. Moisture will be drawn from the south into the state starting on Thursday in the south and Friday morning in the north. Not a super amount of moisture or dynamics associated with this system but the slow movement of the Low will allow for pockets of significant precipitation in Southern and possibly central Utah. The Wasatch will miss the brunt of the system but we wouldn’t be surprised to see up to 6″ above 9,000 ft in the Southern Wasatch on Friday with a couple inches for the northern half of the range. Snow levels will likely drop to 9,000 ft or lower with heavier bands of precipitation so it is possible that the bases of some resorts could see their first accumulating snow. A zonal flow will move the system out of the area during the day on Saturday.
After Saturday, we’ll see the jet sag south and bring the Pacific northwest their first substantial rains and snows of the season. Utah is likely going to be clipped on Monday/Tuesday of next week by this system as it passes to our north. The GFS has been a little be more aggressive than the Euro for the most part, depicting at least a chance for some light accumulations in the Wasatch. Obviously, the second system will favor the northern half of the Wasatch. Beyond Day 7, models are hinting at ridging returning to the area for the second half of the week. But the CFSv2 and GFS have both hinted that this ridging could be short-live as the westerlies return to the Western U.S. during the last week of October.
Overall, don’t see this week’s system as significant enough to be anything more than another teaser, especially for Northern Utah. But we are taking the typical steps toward winter, so it’s only a matter of time before we’re seeing snow pile up for good.
Keep praying for snow! If you take care of the superstition, we’ll take care of the science.
Monday AM update:
Update this morning is mostly to make mention that the cut-off low that we’ve been writing about for the past week or so looks like it will pass to the south of the Wasatch. It’s long been suspected that it would favor southern Utah but to what extent remained in doubt. Looks like the center of circulation will most likely track over northern Arizona. This means that Southern Utah could see significant rain, with snow above 8500 ft, but Northern Utah will only see occasional and light showers. So for the heart of the Wasatch, I would expect at best just a couple inches above 8,000 ft. during the Friday-Saturday timeframe. The Northern neck of the range, including Snowbasin and PowMow, might be just a touch too far north to see anything accumulate, but of course, you never know and there is a chance the track could move north again.
For the long term, the models, which for a couple days were showing a very active pattern beyond the weekend, have now back tracked and instead now show the storm track mainly affecting the Pacific Northwest. This seems like a reasonable solution for now and is often the first step in bringing a winter-like pattern to Utah. For right now, I would expect very seasonable temperatures for the next 10 days with periodic, but not overly dramatic, temperature swings. Aside from the chance of showers on Friday and Saturday, we don’t see any major systems in the 10 day. Great Fall weather. Stay tuned . . .
Saturday morning update:
Cool temperatures continue this weekend with quiet, sunny weather. As the California low mentioned in our previous discussion slowly drifts into the desert Southwest over the beginning of the upcoming week, we’ll see an increase in moisture from the south starting on Wednesday in Northern Utah. With the bulk of the moisture from this system arriving on Thursday and Friday. While not a particularly cool system, it is likely that we’ll see snow high in the mountains. At this time, we are not expecting anything significant, and any snow that does fall will be of the wet variety–good base building snow.
Beyond that, signs are pointing to an unsettled and cool pattern continuing. GFS in particular has been very consistent for the last 5 or 6 runs with a trough entering the area from the northwest during the weekend with another stronger trough on its heels for early in the week of October 15. This is the type of pattern that, if it verifies, could go a long way to building a base for the Wasatch. Good news! Now I know there are a lot of backcountry enthusiasts out there that are convinced that it shouldn’t snow until November. After last year I don’t blame you–but that was a very rare occurrence we literally had 18-24 inches of snow that sat on northern slopes for 6 weeks or so before more snow fell on it. It is unlikely for that to happen again. Personally, I would rather have a couple feet of wet snow now than wait till November and build a base of champagne powder. So anyway, while this pattern is still very much developing in the models, it is looking increasingly likely that at the very least, Autumn is here to stay. We are going to keep an eye on this for you as always, despite going on a bit of a vacation this week–the updates might not be quite as frequent or detailed as normal 😉
Keep praying for snow!
The first part of the advertised cool down began yesterday with high temperature about 5-10 degrees lower than they were on Tuesday. Today is another near average day before temps will dip below average tomorrow through the weekend along the Wasatch Front with the arrival of a reinforcing shot of cold air that will push slightly farther west than yesterday’s. We, however, will see nothing in the way of precipitation, as all of that action is well to our east. A few more clouds tomorrow and light breezes is all that will accompany the cooler temperatures. Night time temps tomorrow night through the weekend will dip below freezing in mountain valleys and some of the colder low valleys as well. Time to cover up or harvest the plants.
Next week, the closed cut-off low pressure system that has been sitting off the California coast will gradually move inland. Over Southern California, Southern Utah, and Arizona. Not too much dynamics or moisture associated with this system but it will bring us a slight chance of showers–with the best chance for precip mostly to our south. The timing on this looks to be about Wednesday of next week. Southerly flow that develops ahead of the low may warm us up back to near average by Tuesday.
Everything beyond the next 7 days is very vague at this point but there is nothing to suggest that the blocking high pressure ridge parked off the coast of British Columbia will be going anywhere anytime soon. So our best chances for snow will remain with cut-off low pressure systems or weak, cool systems that periodically drop down the east side of the ridge. El Nino, which for a couple weeks, was looking a little stronger in the models, now looks weaker again. The CPC has now given only 55% chance of development. I was never as sold on it’s development as they were so I’m not too surprised. I also believe that an ENSO neutral year or a very weak El Nino is better for Northern Utah’s chances at seeing average or above precipitation. La Nina has a tendency to favor the Northwest, El Nino – the southwest, but an ENSO neutral year often aims the jet stream more at the mid-latitudes (including the Wasatch). Teleconnections begin to play a significant role in our weather this time of year, but as of now, most of those are in neutral states and forecasted to stay that way for at least the next ten days or so. We’ll keep an eye on those as well as the MJO over the next few weeks to see if they show signs of livening up, whether good or bad.
For the month of October, it’s looking mostly dry until at least mid-month. After that, the CFSv2 suggest near average precipitation through the end of the month. So overall, I think we’ll be below normal precip-wise and near normal temperature-wise for the month barring some drastic change in the pattern. Not too much excitement as of yet, but remember, things can change in a hurry once the Pacific steps on the gas.
As far as seasonal outlook, not much reason to change my original snow forecast for the season of about normal. If a weak El Nino does indeed develop, the southern parts of Utah may be more likely to jump above average with the North slightly below. But I’m guessing that El Nino will be mostly a non-factor for us this winter so most areas of Utah will have equal chances of seeing above/below average snowfall. Sounds a bit like a cop-out to say just an average year, but the best we can do is call it as we see it, and right now there isn’t anything out there to suggest otherwise. Besides, I think after last winter, we’d all be quite happy with an average snow year, right?