Tuesday, December 1, 2009
I just viewed the latest forecast output (computer models initialized at 4 PM) and also the uncertainty (ensemble) forecasts from NCEP (the National Weather Service forecasting center) and ECMWF (the European Center for Medium Range Forecasting). The die is cast for the next 5-6 days: dry and cool, and getting COLD.
With clear skies, temperatures have already fallen into the 30s in much of the areas, some colder spots are already below freezing. Tomorrow will be like today...perhaps with some fog in low spots in the morning. With an increasing offshore pressure gradient and easterly winds aloft, the fog probably will not be extensive or long-lived. Sun tomorrow. No precipitation at all. Ditto Thursday. Friday a weak disturbance will pass to our north...all we will get is some clouds...particularly the northern portion of the State.
Saturday again cool and dry with sun. Sunday will be interesting as a strong surge of cool air pushes into the region with strong easterly flow in the lower atmosphere. Winds will howl through the Fraser River Gap and flags will be flying in Bellinghan. Strong easterlies in the Strait of Juan de Fuca. But it looks dry.
Monday and Tuesday could be the coldest we have seen in a long time...particularly in sheltered spots. My advice...you have delicate plants--cover them with mulch, bags, or whatever you do. Or bring them inside. This is potentially plant killer weather--but we will know more in a few days.
Some of the forecast models keep it cool virtually all next week, others have different solutions...but no need to worry about that--I am more than content to forecast 5-6 days out.
Special Lecture: I will be giving a noon-time weather lecture ("Is Rainfall Getting More Extreme?") and a book signing at Elliot Bay Books, December 2 at 12 PM. Downtown in Pioneer Square
KIRO TV WEATHER SPECIAL: Wednesday, Dec 2 at 7 PM. For more info check out: http://www.kirotv.com/station/21774954/detail.html
Posted by Cliff Mass at 9:38 PM