Weather Flow - weather on the goPeter Detterline
I was fortunate enough to try out Weather Flow, a portable weather station for the smartphone. The unit plugs into the audio port of the phone. Setup was a bit challenging in that there were no real detailed instructions. It took some time to figure out what button to push to set it up correctly. However, once done, the unit initialized and required a compass bearing as you swung the unit around in a figure 8. You are now ready to take accurate weather readings with your smartphone.
I was travelling across the United States, so I figured this
would be a good test of its abilities.
The unit would be tested at high altitudes in the mountains, hot and
humid conditions in the plains, and the dry and hot climate of the desert. It would be subjected to thunderstorms, high
winds and deep night temperatures (I am an astronomer by profession).
“What is that thing you have there”, the Park ranger asked
me at Boynten State Park in Wyoming. I
smiled, and had him look over the compact Weather Flow meter. It really looks cool, and makes you feel like
a scientist. After turning the unit on,
hold it vertically for one minute as it takes its readings. At that point you may place some descriptive
notes about the weather, and then save your readings for others to see. You may also share your weather reading
through the media of your choice (email, text, facebook, etc).
So how well does it work?
The wind speed anemometer works incredible well and records the average
wind speed as well as gusts. The lowest
wind speed recorded was 0 mph and the highest was 32.5 mph with a storm ripping
across the lake at Boynten State Park.
Interestingly, the anemometer starts to “sing” at 20 mph, but doesn’t affect
performance.
Being a travel instrument it will be subjected to all sorts
of environments, and the thermometer seems most prone to error unless you take
some precautions. At 9,100 feet altitude
in Westcliffe, Colorado, the Weather Flow Meter measured a temperature of 82.3°F when I brought it
outside, but the local temperature read 59°F. I took another measurement immediately and
the unit measured 71.2°F. This was also apparent when in the
desert. I keep it in the shade of the
air conditioned car and measured a temperature of 96°F when the temperature outside
was recorded at 110°F. At Grand Teton, Wyoming, the unit was in the
car, (but in the Sun), and measured a temperature of 100.2°F when the temperature was
60°F. Like any thermometer, keep it in the shade and
give it time to adjust.
Relative humidity is calculated by a wet and dry bulb
temperature. Well, at least back in my
meteorology days in college using a sling psychrometer. Of course there a number of ways to measure
this today and my guess is that the unit uses electrical impedance with a
relative humidity sensor and a dew point probe to make its measurements. It’s not bad for such a compact instrument. I have noticed changes compared to local
instruments, but usually only a few percent.
However in a rainstorm in Ohio I recorded a relative humidity of only
74%.
The ultimate test. My
good friend, Dave Fisherowski, was kind enough to let me test the unit, and
also has one of his own along with advanced weather instruments. So we stood together outside his home letting
the units acclimate for a good fifteen minutes in the shade. The table below shows our results along with
his local weather station.
Wind Speed
Gust
|
Wind Speed Lull
|
Temp.
F
|
Pressure in Hg
|
Humidity
|
|
My Unit
|
5.1 mph
|
3.6 mph
|
75.9°
|
29.50
|
53%
|
Dave’s Unit
|
5.7 mph
|
3.8 mph
|
75.4°
|
29.56
|
55%
|
Weather Station
|
Doesn’t report
|
3.2 mph
|
77°
F
|
29.93
|
63%
|
Retail Unit
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