SnowCam Revisit October 2018
IMPORTANT NOTE: THIS IS NOT UTILIZED FOR CoCoRaHS or other official Snow Depth reporting.
NOAA / NWS loves SnowCams...
Contact your local forecast office, and give them the links to your 'real-time' SnowCam imagery.
SnowCam Gauge Fabrication
The Snow Depth Gauge used here
is available from the CoCoRaHS store at Weather Your Way.
IMPORTANT: This SnowCam Gauge project should NOT be used for official snow depth measurements and reporting! ALWAYS follow the protocols specified by the specific affiliated agency: (for example) CoCoRaHS .
What, Why, Whatever
The Snow Depth Gauge mounts on a high-density polyethylene kitchen 'cutting board'. Illustrated is a previously used, and restored, 12" x 18 "x ½" board. Suggest using a ¾" or 1" thick for added stability. The textured surface tends to hold precipitation in place during the initial onset much better than a 'smooth' surface, and may enhance temperature response.
This style "Snow Depth Gauge'" has a tendency to 'flutter' in gusty winds. To minimize that effect, it may supported in the rear by a rod, or similar, ... this example is hollow fiberglass, with a metal open ferrule at its end. This reinforcement helps gauge mount remain tight, and provides some other subtle benefits. A 'hollow tube' is much better than a 'solid rod' for the later support mounting' step.
This Board is painted BLACK for several reasons... including better visibility of early onset flakes, and it simulates the 'temperature' response of paved surfaces. MATTE BLACK appears overall as the BETTER option for 24/7 current environmental snow presence during event onset and melting conditions..
If supported at 'Grass Top' level, rather than directly on ground - or elevated -
observations and experience indicate:
When NOT covered with snow, in cloudy conditions, this illustrated board's heat content mirrors closely slower air temperature changes. Dramatic temperature changes, or recovery from 'sunlight' conditions, a 'naked' board lags by about 10-30 minutes. Previous use of the recommended 'thicker' board indicates the temperature response is not significantly different under similar conditions.
The support member, and the 'wire supports' for the gauge, will be inserted into the cutting board. Drill exact size and spaced 'wire' holes through the board, and an exact size 'rod' hole about two thirds through -- centered between, and an **eighth inch** behind the wire holes. **This obviously will vary depending on type and thickness of the support**
The board's 'viewable' surfaces are prepared with Rustoleum, flat-black, or matte Barbecue Grill spray paint. Thoroughly clean the surfaces with alcohol, or similar, to remove oils, etc.. If you don't, the paint may not bond well. Follow paint instructions. Thick coat is NOT good... TO ENHANCE BONDING: When no obvious 'shiny' areas are visible - 30 mins or so - heat the painted areas very gently, and uniformly, to no more than 200 °F (will melt above 220°F) and allow to cool and cure overnight... After 'curing', it is possible that a very minor 'dust' will be 'un-bonded'... rub VERY gently with soft cloth, and flush the surface with clean water. Suggest repeat this step after first coat is cured. ( IF you have a matte Black material board you can obviously skip this step.... just make sure it is not 'slick' and/or 'shiny' ... ) .
It is easy to over-heat the board and it may 'warp' toward the middle.
That can be fixed to large extent:
Turn the board upside down, place it on a super-flat, very clean, very smooth hard surface. Heat the middle two-thirds of the board across the full width,. and press the entire board firmly against the surface until it cools. Voila!
Support and Gauge
File some lateral grooves in the last quarter inch of the support, Force it into the hole... it MUST be tight and perpendicular,... then. in this case, the ferrule is heated until the board composite softens just enough that it can be forced downward a small distance to 'bottom out'... continue until material melts around the support and seals against it. Remove Heat... should form a secure, permanent attachment when 'melt' solidifies.. MAKE SURE the support is anchored, and perpendicular! (Keep the heat confined,... excessive heat may cause the board to 'warp').
Trim the longer 'gauge' wire supports to about 3-4" below the board bottom, and 'round-off - smooth - blunt - deburr' the cut ends,... you might poke a nasty flesh wound otherwise... heh... ouch....hurts.
The stick wire rods are secured with 'heat shrink' tube, pressed tight against the bottom while still hot. Score some horizontal grooves in the projecting metal rods, for the Heat Shrink to 'mold' with, preventing slippage... It will take abut 3 - 4 layers of 'shrink' to form a 'secure' 'nut'... ...again, avoid excessive heat on the board composite itself.Spread the two protruding wires apart slightly at the board.,.,. and make sure the 'shrink / spread' process holds the gauge tightly. The 'shrink' layers are easily removed with a sharp blade if necessary in the future...
The Support and Gauge are secured together with 'wire ties', in this case. Don't over-tighten... just 'firm'... don't 'bend' the gauge material.
A couple of 'spirit' levels are attached to this build... much more convenient than a 'hand carried'...., especially when the assembly may shift at times over the season...
One Final Thing
To minimize the UV and Environmental effects, prolonging both the life, and presentation of your hard-earned gauge use "303 Aerospace Protectant' all over the assembly. Follow instructions. Well Worth The Added Cost, since it will also help such things as CoCoRaHS and similar rain gauges, ISS assemblies, etc.