Forecast models are in agreement that a longwave trough will sharpen tomorrow over the Great Basin. This feature will drive offshore flow for the extended period as it slowly moves eastward. The story for potential fire weather impacts will likely be low humidity and rising temperatures, as opposed to strong and widespread winds. This process of shifting to offshore warming events has been delayed a little this year as the subtropical jet stream has remained strong.
The highlight of this message will not be the first offshore wind set up, but the general pattern shift of the jet stream moving into the midwest, and individual shortwaves moving down stream of the longwave trough for bump up in wind speeds. This could bring very dry and warm weather to California with increasing fire weather issues.
The other highlight will be the potential for a significant offshore wind event or atmospheric river around 10/14, as multiple Western Pacific tropical cyclones and mid latitude cyclones phase and pile into the Gulf of Alaska region, and blocking high pressure over Northern Canada forces it down stream.
As always it is important to factor in early season low pressure systems are shown too far west most of the time, and offshore wind events can be forecasteable in the mid-long term because the north pacific high is on a predictiable amplification cycle.
