Kestrel Meters: Keeping Track of the Weather in the Field
As we move from winter towards spring, the weather can change rapidly. Interesting weather can make for interesting photos, but in order to be prepared for what might be coming, it helps to be armed with as much data as you can. Kestrel handheld weather meters make this a breeze, if you'll pardon the pun.
I really like gadgets. I've found that this tendency is not uncommon among photographers. A couple of years ago I came across Kestrel meters while searching the internet for something unrelated. Manufactured by Nielsen-Kellerman based out of Chester Pennsylvania, Kestrel meters pack some amazing technology in a package less than five inches long and weighing around three and a half ounces. Basically, these things are very capable weather stations that you can fit in your pocket.
There are a range of models with a corresponding range of features. I went with the Kestrel 4000 which can measure and record temperature, relative humidity, barometric pressure, wind speed, dew point, heat index, wind chill and more. It even logs data at set intervals and produces graphs so I can track trends. It runs on two AA batteries that last forever. The unit starts up quickly and the controls are quite responsive. There's a built-in backlight so you can read it in the dark without a flashlight. Its waterproof and it floats. Street price for the Kestrel 4000 is around $250, a bargain for what it offers.
When I'm travelling, I can sometimes check weather online if I can find a Wi-Fi access point, but with the Kestrel 4000 I can keep tabs on incoming fronts even in the most remote locations. I can hang it unobtrusively near where I'm camped and let it do its thing. If the wind shifts direction or it looks threatening I can review its logs to gauge what might be coming my way. If the weather is awful but the barometric pressure starts to rise sharply I can assume it's going to clear up soon. You get the idea.
Barometric pressure depends on knowing your altitude. The Kestrel actually measures station pressure, the actual pressure the air is currently pressing down with at your location. To convert this to true barometric pressure it needs a reference altitude, something that can be easily obtained with a GPS, another handy gadget I carry with me when travelling.
The manufacturer tests each unit and includes a certificate of conformity certifying its accuracy. I have a real weather station at home (a Davis wireless Vantage Pro 2) and have compared the Kestrel readings against it as well as other published weather sources for the area and the Kestrel does a competent job indeed. They do sell kits to recalibrate the relative humidity when needed but so far I haven't really found a need.
Nielsen-Kellerman recently announced new Bluetooth capable models that are supposed to start shipping by the end of this month. Personally, while Bluetooth does sound cool as someone who likes gadgets, but I'm not really sure it's all that necessary in a handheld weather meter. I care more about current and recent weather rather than long term data storage. The Kestrel 4000 on its own has plenty of memory for my needs. Set to record new measurements every half hour, the unit can hold over 41 days of data. I am unlikely to need more than that. With a stated Bluetooth range of up to 30 feet I guess it would be nice to see what the Kestrel reads without ever even going outside, but since Bluetooth models go for about $100 more than equivalent non-Bluetooth models, it would be hard to justify, even if I didn't already own a Kestrel.
Kestrel meters are highly recommended not just for outdoor photographers but for anyone who needs accurate weather information when out in the wild.