||Description and Instructions
SF Bay Area
How to read a
|Current Conditions and forecast closest to our
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.
||Record applicable high and low tides for coastal
||Gives convection ceiling, top of lift, thermal
indices and winds aloft.
- 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.
- Print resulting chart.
- Locate and highlight the following items for report:
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
- 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).
- Mt. Tamalpais:
- Fort Funston:
- Ed Levin:
- 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:
- 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.
- To be sure you are not using old data, hit the re-load
key on your browser to get the latest info.
- Other data sources include a weather
radio (wind, fog, cloud reports, tides, sunset, highs,
forecast), wind robot reports, and computer subscription
- 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
- Dew point closure is 4.4 degrees F per 1000 feet.
- 1mb = .03 in. mercury
- 1016mb = 30.0 in. mercury