A couple of weeks ago, I journeyed to Zion National Park for some hiking and canyoneering with some family. As luck would have it, the heavy rains that week spoiled our plans, at least that is the way it seemed. We had planned a hike in one of the canyons on the first day, but even minimal rain can inundate the canyons making it a deadly experience.
Flooded Virgin River in Zion National Park
Canyon Showers
It is not uncommon to hear of people trapped or killed by flash floods in the slot canyons of southern Utah. There is often no way out, but down stream and it is best to go under your own power. Caution must be observed to check weather reports and forecasts for the surrounding areas. The high precipitation rate that we observed compounded the danger and caused damage to roads throughout the region.
So, we enjoyed a wet hike in the pouring rain as we worked our way to Angel’s Landing and arrived just as the sky cleared.
Angel’s Landing
The following day we were fortunate enough to get a permit to hike, wade, swim, rappel, and scramble through The Subway.
The reward, a view of The Subway.
Upstream view of The Subway.
Subway Canyon
…And My Point?
Automatic weather stations in areas where capturing high precipitation rates is critical, a standard tipping bucket gauge may be overwhelmed. As the rain rate increases, the measurement error also increases. RGTB-4TM from Dyacon is designed specifically for such conditions. Even with rates of 250 mm/hr to 500 mm/hr (10 in/hr to 20 in/hr) accuracy is +/-3%.
Rain Gauge
The Siphon
The problem with conventional tipping bucket gauges is that simple funnels do not provide a consistent flow rate into the mechanism. When the rain increases, the mechanism is flooded and either the error rate increases or the gauge stops working.
Rain gauge siphon flow control.
RGTB-4 uses a proven siphon mechanism to ensure consistency and accuracy even when the funnel has been filled with water by heavy rains.
…And That’s Not All!
RGTB-4 also has discharge ports which can be used to capture precipitation for later verification and analysis. Just run standard tubing into a closed container so you can validate gauge measurements in a controlled environment. What more could you want? . . . Well, maybe you’d better not answer that.
Eugene
Eugene in The Subway