Re: Rain, Rain,Go Away

On Sat, 28 Dec 2024 18:08:26 GMT, cyclintom <cyclintom@yahoo.com>
wrote:

Yesterday's fore3cast for today was completely wrong. Rather than cloudy and dry it was cloudy and rainy. A good ride day spoied by a poor forecast.

Got it.  You're now an official victim and entitled to a large serving
of sympathy.  Since you didn't bother disclosing your source(s) of
weather forecast info, I can't provide suggestions or alternatives. 

Hmmm... how much rain did you receive in San Leandro? 
NOAA at at Oakland International shows:
  "trace" for the last 6 hrs.
  0.00 for the last hour.
  0.02 inches for the last 24 hrs:
<https://www.cnrfc.noaa.gov/precipMaps.php?group=sf&hour=24&synoptic=0>
<https://www.cnrfc.noaa.gov/ol.php?product=twentyfourhourP&zoom=12&lat=37.730&lng=-122.198>
I rather suspect that you're exaggerating the problem.

However, if you want a better prediction, find a web pile that uses
and favors ECMWF data for forecasting.  Most US weather guessing sites
use GFS which (in my never humble opinion) sucks.  I won't offer
anything more specific because you will likely ignore my advice.

Another way to predict rainfall is by measuring the outdoor humidity
accurately.  Right now, my Acurite 00384HD indoor/outdoor wireless
weather stations shows 90% humidity.  It's trying to rain, but it's
not going to happen until the sun goes down.  Typically, the humidity
needs to be above 95% for rain.  The problem with this method is that
many humidity sensors are not very accurate at humidity extremes.  I
have a more accurate psychrometer (Bendix 566-3) but only use it to
calibrate the weather station sensor.
<https://www.google.com/search?q=bendix+psychrometer+566-3&udm=2>
 
You can follow the action using NWS data. 
This is for Ben Lomond CA (my house):
<https://forecast.weather.gov/MapClick.php?w0=t&w3u=1&w5=pop&w6=rh&w7=rain&w14u=1&w15u=1&AheadHour=0&Submit=Submit&FcstType=graphical&textField1=37.0813&textField2=-122.093&site=all&unit=0&dd=&bw=>
This is for San Leandro (Tom's general location):
<https://forecast.weather.gov/MapClick.php?w0=t&w3u=1&w5=pop&w6=rh&w7=rain&w14u=1&w15u=1&AheadHour=0&Submit=Submit&FcstType=graphical&textField1=37.7284&textField2=-122.1586&site=all&unit=0&dd=&bw=>
Hmmm... no rainfall in San Leandro this morning.  Are you sure it was
raining?




--
Jeff Liebermann                 jeffl@cruzio.com
PO Box 272      http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann      AE6KS    831-336-2558