Author Topic: Accurately Measuring Snowfall with a Snowboard  (Read 536 times)

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Offline Doren

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Accurately Measuring Snowfall with a Snowboard
« on: January 17, 2022, 05:50:40 PM »
I searched the forums, but could not find this particular question, so here it goes.

I purchased a 24"x24"x1" white professional cutting board, bolted it to a birdhouse pole mount, which attaches to a C-Stand & balanced everything. The unit is exactly 6' tall, so I am able to take measurements at the perfect eye level, plus raising it above our 4' chain-link fence.

I see most snowboards on the ground or on " elevated surfaces", such as deck railings, etc... Which led me to believe that having it elevated 6' in the middle of my yard, at least, 20' from any obstructions would be perfectly fine, but I can not find anything online to reinforce this theory.

Can anyone lend some advice, suggestions or an answer that what I've built should yield accurate snowfall measurements? It's greatly appreciated. Photo attached. Thanks!

Offline CW2274

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #1 on: January 17, 2022, 06:12:47 PM »
I've never used a snow board but would think wind would be a problem with it elevated, especially if it's dry humidity and powdery. 

Offline Doren

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #2 on: January 17, 2022, 06:18:52 PM »
Thanks so much! Yeh, that was my major concern also. I could always unbolt & simply put on the ground. I was just hoping that this would work because the ease of measuring is very easy being elevated to my eye level. Your point is extremely valid. I wonder if anyone else has any thoughts. Thanks again!

Offline CW2274

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #3 on: January 17, 2022, 06:21:04 PM »
You're welcome. There's quite a few here who use them so I'm sure you'll get very good advice.

Offline Jasiu

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #4 on: January 17, 2022, 06:28:34 PM »
Have you seen the NWS guidelines?  If not, you can get the PDF here:

  https://www.weather.gov/media/coop/Snow_Measurement_Guidelines-2014.pdf

What they have to say on siting:

Quote
Put your snow measurement board (SMB) out and mark
its location with a flag or some other indicator so it can be found after a new snowfall. The SMB
should be located in the vicinity of your station in an open location. Find an area where wind
effects and drifting are minimized and far enough away from buildings or trees where snow
blowing off of higher structures is unlikely to fall onto your SMB.

It seems implied that this is on the ground and that's always where I've had mine.  Yeah, I usually have to bend my creaky back to see exactly which tenth-inch line the snow is up to. Such is a hazard of the hobby!

Offline Doren

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #5 on: January 17, 2022, 06:34:06 PM »
Thank you! Yes, I have the NWS guidelines & have read multiple webpages on the matter, but I swear I had come across some snowfall measurers that used elevated surfaces, such as deck railings, tables on decks, tables in yards, etc... to yield their results. So I thought I'd make something that was elevated since we don't have a deck, table, etc... I was under the thought that the reason the board was recommended to be so wide & long was to compensate for wind, but that assumption could be absolutely 100% incorrect.

Offline Cutty Sark Sailor

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #6 on: January 17, 2022, 09:02:53 PM »
Secret wisdom only revealed to advanced wizards:  It's not one measurement, regardless of location.  It's several, averaged.
https://media.cocorahs.org/docs/MeasuringSnow2.1.pdf
« Last Edit: January 17, 2022, 09:07:10 PM by Cutty Sark Sailor »
 

Offline Doren

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #7 on: January 17, 2022, 11:33:00 PM »
Yes, NWS responded & have just told me the same thing. Thank you! But, no to an elevated snowboard? Or multiple evaluated snowboards for multiple measurements? Or just multiple snowboards on the ground for multiple measurements? Or evaluated & ground snowboards for multiple measurements? Thanks!

Offline Cutty Sark Sailor

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #8 on: January 18, 2022, 07:06:52 AM »
You have to decide if it's accurate for your purposes. Whatever, you will 'accurately' be shown what accumulates within that specific 2 sq' area you're exposing, at whatever time you look at it.

Now, to be totally patronizing I suppose: #-o
 Depending on when you measure, it will likely be at odds with nearby measurements anyway... but it should be obvious that an 'elevated board method' is NOT the standard protocol the world uses. Elevated surfaces can be somewhat erratic depending on temps, winds, snow type and density, versus any location's historic consistency  of ground based protocol.. I know this, because I can see it on my elevated surfaces compared to ground averages. (See my last comment below, however).

We CoCoRaHSians take a 4" diameter core, of 'selected area's snow depth, and also measure SWE / and S/L ratio.  Water equivilent is very important, not just 'depth'. We're interested, and so is NWS, on what's on the ground, roadways, etc. elevated surfaces are important, but they're elevated, and I suppose the assumption is that elevated surfaces will have at least as much volume as ground based.
1. Elevated freeze before ground, theoretically elevated should accrue 'higher' snowfall. Depending on WHEN you measure.
2. Snow compacts as it sits. Measure soon.
3. Your airborne composite board will follow the 'air temp' with some lag.  The ground is a tougher nut to crack on temps.
     'Bridges freeze  before Roadways'
4. The ground will have snow remaining, usually, long after the elevated has 'cleared', air temps and cloud cover not withstanding.
5. At stable air temps <32, and ground already frozen... the 'new fall' measurements won't differ that much for bare surfaces at any specific location.

A two-axis level installed on my SnowCam 18" x12" x 1" poly cutting board, which sprayed black with Rust-o-lem enamel (since it sticks better--)
It's Black for two reasons:
1. It shows snowflakes better than white... (duh - it's for the camera!) ... 
2. Black color on that specific board composition, size and thickness seems to reflect Road and paved surface temperature response in accumulative and melt phases. For support of it's efficacy, I give you the Louisville WFO (LMK) which will often refer to it's stream in their situation room.

The 'SnowCam' board is NOT used for actual 'reported' frozen precip.  Those follow the guidelines. This is a visual rep only, and because of the SnowGauge, etc, will, at first glance, appear to be under-reporting depth... once the observation trick is understood, it reflects pretty accurately the average current depth.

Now, the 'unadvertised special':  :-$
I do have one, specific, secret little place I've learned to use as a 'baseline', 'reference standard', or quick and dirty fast report.  No matter what any of the other 'official' measurements show, because of it's location, composition, structure, typical wind patterns, spiritual or magical laws, whatever....  it is ALWAYS within a tenth inch of whatever 'official' average I compute, for depth and virtually exact same SWE.  Everybody should be so lucky and have a special spot, so to speak.
« Last Edit: January 18, 2022, 07:21:01 AM by Cutty Sark Sailor »
 

Offline Doren

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #9 on: January 18, 2022, 03:41:38 PM »
Excellent! Thank you so much for all the information. But it looks like it's time to dismantle my creation sadly based on all the information. I had thought it would be inaccurate even for me. Thankfully it only took 1 storm for me to realize that with everyone's help. Now I can get back to reporting accurate results from a ground placed snowboard. We typically have decent winds only adding to the inaccuracy of an elevated snowboard. Thanks again for all the info, I've copied/pasted and logged this entire thread in Apple Notes. Thanks everyone!

Offline ed2kayak

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #10 on: January 18, 2022, 04:04:01 PM »
Secret wisdom only revealed to advanced wizards:  It's not one measurement, regardless of location.  It's several, averaged.
https://media.cocorahs.org/docs/MeasuringSnow2.1.pdf

I follow this guide and report to CoCoRAHS.

They also have some YouTube video's.

https://www.youtube.com/watch?v=2zbDygoJ2D4
Ed
CoCoRaHS PA-CD-6,  Weather Underground KPAMECHA7, CWOP DW5425

Offline Doren

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Re: Accurately Measuring Snowfall with a Snowboard
« Reply #11 on: January 18, 2022, 04:48:46 PM »
Awesome! Just bookmarked them. Thanks again!

 

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