This week's weather poses an interesting forecast problem: what do you do when the most reliable computer model is predicting something completely out of whack for this time of year?

Many of the major computer models, including the ECMWF (which has been the most reliable so far this winter), show a giant cutoff low developing in the western Atlantic later this week. A cutoff low is one that is cut off from the jet stream, and therefore not steered by high level winds. It just sits and drifts. A huge blocking high to the east is forecast to act as a giant wall, keeping this cutoff low spinning near the East Coast and possibly even pushing it westward (in other words, backwards).

This scenario is highly unusual for early February. It is more typical of March or April. And yet, several computer models show it happening. The key issue is what this means in terms of precipitation and wind for our area. Southern stream energy will also come out of the southwest and possibly merge with this cutoff. Right now, 3-4 days in advance, all that is certain is a major question mark for later in the week--possibly some rain or snow, but also very possibly nothing at all. It is not the week to bank on long term forecasts.