Re: [Paddlewise] Weather forecasting

I'd be the last to denigrate the value of "local knowledge" and 
"observation," but Richard Smith's suggestion that barometers have no 
place in short-term forecasting is simply tosh. 

Changes in pressure over time -- up or down, steep or gentle -- are 
important indicators of approaching weather systems.* And you don't 
need a barograph to discern them. A plain-vanilla barometer and a 
notebook will work just fine, thank you. Simply record barometric 
pressure at set intervals (2 hours is a good place to start) and then 
connect the dots. This isn't some new-fangled idea. Sailors have been 
"eyeing the glass" and watching for changes since the days of Admiral 
Fitzroy. 

Which barometer, then? My old Thommen Everest baro-altimeter has gone 
everywhere with me in the last twenty years. It's about as delicate as 
a Hummvee. Carry it in a double Zip-Lock bag and fear nought. 

What sort of notebook? Bound engineers' field notebooks (the Dietzgen 
S400V is a good one) are excellent logs. The orange color makes them 
hard to lose, and the paper, though not waterproof, won't disintegrate 
when it gets wet. Still, it pays to bag them.

For those with deep pockets and a fondness for gadgets, Casio (and 
others) sell digital watches incorporating a recording barometer -- a 
barograph you can wear on your wrist, in short, and one that's 
waterproof to 100m, to boot.

Barometers and barographs aren't magic, of course. No forecasting tool 
is. But they're well worth taking along -- and using -- on any trip 
outside your back garden.

Terry

* For guidelines in interpreting such changes, see, for example, 
pp. 57-58 in Jeff Renner's _Northwest Marine Weather_. (And, yes, 
Renner's a "professional meterologist." His is expert counsel. Faint 
hearts take comfort.)


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