The National Weather Service (NWS) office in Seattle issued a Special Weather Statement yesterday given the possibility for damaging winds Thursday. But, forecasters also note, computer models disagree whether wind gusts will top at over 20mph or over 50mph.
The statement was issued for western Washington locations between the Olympics and Pierce County north to western Whatcom County. Forecasters say the concern is due to a deep low pressure system that is expected to “move east toward Vancouver Island, then southeast, eventually setting up a strong southerly gradient over Western Washington around Thursday.”
This system is also expected to bring heavy rains to the area with the Ferndale area forecast to receive up to an inch of rainfall on Thursday.
But as the graphic above shows, NWS forecasters warn, “Details differ significantly between and within models. For example, over the last 24 hours the GFS alone has shown peak [Portland – Bellingham] pressure differences ranging from +11 mb (breezy to windy) to +19 mb (very strong damaging winds).”
In short, while there remains uncertainty regarding wind strength on Thursday, a possibility for damaging winds merited issuing the statement.
For comparison, the following graph is an example of a forecast wind event last October and computer models were in relative agreement the day before the event.