Diablo Winds


 Foehn-type Winds -- Downslope winds that flow outward from a region of dynamically-induced surface high pressure located over a region of elevated topography.

Diablo Winds -- Foehn-type winds in the Bay Area.

Santa Ana Winds -- Foehn-type winds in the Southern California coastal sections.

 


Basic 500 mb and Surface Pattern for 1200 UTC 13 October 1997

Click to See Larger Version of This Image

This chart shows a plot of the surface information for 18 UTC 10/13/97.

1. Describe how the pressure field over California differs from the pattern we have discussed for the WARM SEASON.

2. Describe the windflow you would expect in the Bay Area from such a pressure distribution and how that differs from the windflow the Bay Area typically experiences in the WARM SEASON.

 

Click to See Larger Version of This Image

This chart shows a plot of the surface wind information for 1900 UTC 10/13/97.

3. Describe how the pattern shown correspond to what you would expect from the weather pattern shown in the surface chart in the last section.

4. Describe how the windflow shown differs from that experienced in the summer.

 

This chart shows a plot of surface information superimposed on the visible satellite image for 16 UTC 10/13/97. 

5. Explain the lack of fog along the coast is given the pattern you discussed in the last two sections.

6. Examine the 500 mb chart given at the top of the page. Now relate the charts and discussions for this in-class exercise ot the definition of "foehn winds" given at the top of the page.