Soaring Forecast

Links Description and Instructions
NWS SF Bay Area Forecast Discussion

NWS Oakland Airport
How to read a

Terminal Forecast. 
Concord, CA

San Jose, CA

Sacrament, CA

San Francisco, CA

Current Conditions and forecast closest to our sites.

High temps to be used in report below. Write down San Jose sunset time for Ed Levin closure.

Record pressure at each city and calculate difference to get probable wind strength and direction. Also get marine forecast from SF page. 
San Francisco Tides Record applicable high and low tides for coastal pilots. 

Enter Forecast High
SF Bay Area:

Gives convection ceiling, top of lift, thermal indices and winds aloft. 
  1. Plug in San Jose or Concord expected high temperature at left. Or, click here to customize forecast for a different region. If the site is down, here is an alternate source for the data.
  2. Print resulting chart. 
  3. Locate and highlight the following items for report: 
    • Convection ceiling at expected high temp. (Altitude at intersection of dry adiabatic line and temp line.) 
    • Thermal Indices at 1000 or 500 increments, from surface up to where it's no longer interesting. 
    • Top of lift rule of thumb is altitude where thermal index equals -3. 
    • Winds aloft are at the end of Kevin Fords data. Convert Degrees (270) to directions (West). 
  4. If chart indicates a minor temperature change would drastically alter convection ceiling, start again at number 1 above, but change the temp in step 1. (Previous temp plus or minus 5 degrees, whichever is interesting.) Note the change to results in step 3 as part of your report. For example "If temps are 5 degrees higher than forecasted, convection ceiling raises to XXXX and top of lift improves to YYYY".)
  1. Mt. Tamalpais:

  2. Fort Funston:

  3. Ed Levin:

  4. Mt. Diablo:
Record average direction and velocity from robot reports. Also note any gustiness. For example, 8-28 MPH (or any difference in velocity greater than about 15 MPH) over 15 minutes indicates gusty conditions. 
Instructions and Notes:
  1. Download and print this Adobe Acrobat Document then use your browser to visit the recommended source sites and fill in the blanks. If you don't have Acrobat, use this web page as a guide, and scribble your notes on a napkin. 
  2. To be sure you are not using old data, hit the re-load key on your browser to get the latest info. 
  3. Other data sources include a weather radio (wind, fog, cloud reports, tides, sunset, highs, forecast), wind robot reports, and computer subscription weather services. 
  4. Interesting facts: 
  • Rule of thumb: A difference in pressure between SF and Sacramento of .03 in. implies soarable winds at Funston. .05 to .08 is ideal. Greater than .10 is usually blown out.
  • Dew point closure is 4.4 degrees F per 1000 feet. 
  • 1mb = .03 in. mercury 
  • 1016mb = 30.0 in. mercury