We’ve started mentioning the potential for a change in the weather a bit more than a week ago. Now that some of that precipitation is less than a week away on the models, more forecasters are beginning to jump on board with the possibilities.
There’s good news and bad news since we reported last. Rather than a couple of big storms, it’s looking more like there’s a potential for a longer series of small storm. The trough seems to be setting up just a bit farther north than we would like to be, which will decrease the total precipitation. That positioning also leaves us on the southern, hence warmer, side of the jet stream. Bryan Allegretto at OpenSnow.com suggests that snow levels will run about 8,000 feet, dropping to 7,000 feet later in the week.
Here’s the GFS Total Precip Forecast through the 28th. You can see that we would be much better off if the trough sags about 200 miles further south.
BA’s forecast today on OpenSnow.com suggests that there will be multiple waves of wet arriving over the next two weeks. BA posted a model run of the GFS that looks pretty progressive for this time of year, bringing the potential for an inch of moisture along the crest.
Overall in the longer term, and we have avoided talking about this, there seems to be more positivity in the long range possibility for an El Niño even this winter. Forecasters had all but given up on that possibility by mid summer. The latest prognostications suggest that there is a 67% chance of an El Niño event this season. They also suggest that the combination of an El Niño with a +PDO (Pacific Decadal Oscillation) is more more likely to lead us to a wetter pattern. The scary thing is when forecasters look at the analogue years, which are the years where the big patterns were similar. The first analog for this season is 2004, which was a banner year for snowfall. But the second best analog for this year is 1976-77, which was one of the driest on record. We have noted that more forecasters are looking at the wetter solution as more likely. Hopefully it’s not just wishful thinking.