Transcript BikeradarNew.ppt

You Can Avoid the Rain!
Weather Tips for Biking
There are a number of
approaches to dealing with this
problem
Or the traditional approach…
Rain Jacket, Rain Pants, Booties,
etc.
Another way to stay dry…
But there is another approach, one
that will allow you to bike on most
days, even ones with rain
Weather Radar!
NWS Doppler Radar
Weather Radar Can Change Your
Biking Life
• Since the National Weather Service put the
Camano Island weather radar in place
during the early 90s, I rarely get seriously
soaked.
• With a little knowledge of NW precipitation
and weather radar, you can protect yourself
too.
Weather Radar 101
• Weather radars can see where precipitation
is falling
• Can also tell the intensity of the rainfall
• Doppler radars can also determine the air
velocity toward or away from the radar.
• Radars can track storms, fronts, and other
major features
• An essential tool for the National Weather
Service and other meteorologists.
The National Weather Service has Installed Doppler Weather
Radars Across the Country
Reading a Radar Image
• Most radar
imagery has
much in
common.
• Intensity of
precipitation is
color coded
(units—dbZ)
Reading a Radar Image
• Black (while in some)no precip
• Grey and pink (520)…light rain…not
too bad.
• Dark pink to greenmoderate rain (20-35)
• Yellows are heavy rain
(forget it)
• Reds and high (don’t
even think about it)
Reading a Radar Image
• Remember the
beam can be
blocked by
mountains and is
higher farther from
the radar.
• Time below is in
UTC (GMT).
– UTC=PDT +7 hr
Important Precipitation Info
• It is RARELY uniform, even on rainy days.
• If you can shift you ride by 10-15 minutes
you can often miss the heavy stuff.
• Shift by 30-60 minutes you can usually do
so.
Example: 4:48 PM yesterday-Heavy
rain…but waiting will be rewarded.
Absolutely Dry
The Best Way to Judge When You
Should Go is To Use Radar
Animations on the web
• Available at many sites: UW, NWS and
others! Humans are very good at this.
– http://www.atmos.washington.edu/~ovens/loops/
– http://radar.weather.gov/radar.php?rid=ATX
Another Great Site: Rainwatch
Rainwatch
Different Situations
• After fronts go through we often have
showers and sunbreaks. Radar allows you
to stay in the breaks!
Showers and Sun breaks
The Most Difficult Situation is
When a Broad Pacific Front or
Storm is Over Us
The Absolute Worst:
Pineapple Express!
Dec 3, 2007
But EVEN THEN,
there were dry spots in
the rain shadow and
some places had less
rain
Where to go for that ride?
• Using the weather radar…and highresolution visible satellite imagery…can tell
you where to go for bicycling…even when
it is raining in most places.
Puget Sound Convergence Zone
Puget Sound Convergence Zone
Rainshadows
Windward
Enhancement
Rainshadow
Rainshadows
The end
Our Computer Models (all online)
Often Can Predict them Way Ahead of
Time