Weather It Is (A Winter Storm Clarification)

Good Evening:

Everyone is talking about it -- next week's snowstorm -- but it necessary to step back a moment.

As I wrote before, the development of a snowy winter storm depends on the phasing of the northern and southern jet streams on Tuesday.  Some of the uncertainty in the forecast may be because the northern system is originating from a relatively data sparse region. On the other hand, two days before our next storm system we still see some large differences in the strength of the 500 mb trough (which is necessary to develop a strong surface low) that is moving in from a region with greater data availability.

Right now, there is a 60% chance of a significant snow storm Tuesday night into late Wednesday.  The snow is more likely after midnight and most likely on Wednesday.

The important point is that 40% of the forecasts do not show a significant snow storm, or 4 out of 10 times we have a situation like this there would be no significant snow.

We need to wait 1-2 days to see how the probabilities change (or, how the jet stream phasing progresses in the forecasts), and then until a day or two before to be more exact about snow amounts (assuming we get this far).

So, it is okay to be excited, but "not" okay to change plans yet -- unless absolute necessary (or possible without too great an expense).

Barry Lynn