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Forecast Discussion:
Our last chance of widespread rains (somewhat widespread, at least) pull out in the early morning hours today. The ridge is going to dominate the western U.S. for about a week now. Figure 1 shows the big swoop of a blue line along the ridge line.
We do have two tropical systems clearly visible on the map. Olivia is headed westward to die in colder water, but Florence is something we'll talk about in the longer range forecast below.
The water vapor satellite image from yesterday (Figure 2) shows the deeper river of moisture getting shoved to the east with the passing trough. The forecast surface map shows better rain chances today off in the southeast 1/3rd of the state this afternoon. We still 'might' see a wandering shower/thunderstorm this afternoon.
As the ridge builds, it is loading up on west coast (and more locally sourced) smoke. We'll see more haze into Saturday (Figure 4).
The longer range forecast:
A week from now, the ridge moves over to the east coast which means we might see a big switch back to cooler and wetter weather next weekend (Figure 5). That ridge is bad news for the east coast. Tropical systems do best under a ridge (where there isn't damaging wind shear). If this current run of the GFS is correct, the nation's capital gets a head on hit by a major hurricane. I'll keep my eye on this all week.
Figure 6 is the next 10 days at a glance. After the moisture and trough pull away today, we get pretty dry and get to about 10° degrees F above normal for the next 5 of the forecast period. This model does not show a big cool down or increase of rain chances out around the 14th or 15th as the upper air map is hinting at (Figure 5) - but that might change.
