FIRE IN THE HOLE, OR NOT...
A MESSAGE FROM TSWAILS
Friends and fellow weatherheads, I'm asking for your help to raise funds for the time I invest in this site and its operational costs. So far it's been a struggle and donations are 48 percent less than at this point last year. I realize times are tough, and we are all feeling the pinch. That's a big reason why this is a no pay site. Many of you are daily visitors and make financial or personal decisions based on the information presented. The majority of you appreciate the honesty, accuracy, and knowledge that you gain. If you fall into any of those categories, I ask that you make a $20 dollar investment in what I feel is a unique and reliable product. That way, we can keep things rolling as they have for more than 12 years. The future is in your hands, and I hugely appreciate the generosity of those who have contributed. So again, if you find value in the site and see the effort that's put into it, please consider a minimal donation to support TSwails today. Thanks for your time and loyalty, TS
GOOD RUNS AND BAD RUNS
For me, weather is about the challenge of visualizing something you can't see. It's hard as hell, but it can be done, more so in the short term than the long. It's a lot like religion and the concept of faith with one difference, with a forecast, a prayer never hurts, but if you've got it wrong, that prayer is never going to be answered. So all you can do is put in the time and effort and believe in what you can't see. In general, it's a good philosophy in just about any kind of work. Certainly nothing profound in that! Anyway, the coming two weeks are going to be interesting as well as challenging. Let's dig in.
I wanted to start this post with a graphic showing vertical velocity anomalies for the 5-day period the 9th through the 14th. Why vertical velocity, and what is it? In weather terms, "vertical velocity" refers to the speed at which air is moving upwards or downwards in the atmosphere, which indicates how fast air is rising or sinking at a given location. Rising air (positive VV) when sufficiently cooled leads to cloud formation and precipitation. Sinking air (negative VV) will not get you much but sunshine and dry weather. The green over the country indicates a large area of positve vertical velocity, (rising air/low pressure). It implies a lot of active weather across the nation thanks to all that lift. Fire in the hole!
Correspondingly, the next 2 weeks did show a wet scenario with abundant precipitation from the Rockies east Wednesday afternoon.
To get such a wet scenario, you have to have a lengthy period of convergence where a fight takes place between cold air to the NW and mild air to the SE. It's called a baroclinic boundary, and you can see it nicely on the GFS the evening of the 14th.
The trough over the west and ridge over the SE United States, is a nice example of a negative PNA pattern, which is shown holding in that phase through the 20th.
The PNA can be a thorn in the side of snow lovers locally if the mean trough is centered too far west. In that case, snow producing systems can sneak by to the NW. In fact, that will happen Saturday, when a snow system just grazes my northern counties and punishes Minnesota and Wisconsin with some hefty accumulations.
Once the Saturday system passes, the cold builds further south and east, pushing the baroclinic boundary with it. At this point, the Arctic Oscillation and NAO both slip into negative phases. That should create enough resistance to keep the negative PNA from overwhelming the Midwest with mild air. So while the pattern remains active, it's still uncertain where we will reside on the baroclinic boundary. The GFS on its Wednesday afternoon run had us and much of the Midwest in the cold sector. Look what that did for snowfall.
What a model run that was, dramatically different from 24 hours ago when little snow was shown. I would take it in a minute. But, before you get all excited, look what the new run of the GFS shows just 6 hours later, it's back to a nothingburger. Oh no, the black hole is back, sucking the life out of our snow.
Something was initialized much differently to change the outcome so much. Guidance is still trying to get a handle on the overall pattern, but this was a trend I did not want to see. Even worse, the EURO has jumped on the bandwagon, showing this for snowfall over the same period.
I have to say, rarely (if ever) have I seen things waffle as much as I have witnessed the past 4 days. It casts a shadow on any snow solution, high or low, going forward. The saying in the weather world is, "the trend is your friend". If that's the case, snow prospects have taken another big hit.
If by some chance significant snow does come to pass, you can bet your bottom dollar, cold will follow. Without it, a far more tolerable brand of chill results. Until we know for sure, it's an open verdict. No sense speculating anymore. It will be interesting to see where trends end up tomorrow. Sooner or later, a consistent solution will hit and stick. For now, this is a train wreck!
I must say, this constant flipping of models is tiring and getting old. It never seems to be a problem elsewhere as much as it is here. Maybe it's aliens or mad cow disease. From my perspective, a diligent prayer is in order. Thanks for playing along. Roll weather and if you can spare a donation, I will see to it that it's money well spent....TS
