New NWS snow measurement guide

[uncle W]

 take photos or videos at the end of each event if possible...This way you'll have a clear picture of what really happened... :snowwindow:

[famartin]

 take photos or videos at the end of each event if possible...This way you'll have a clear picture of what really happened... :snowwindow:

 

As mentioned above, there is a climatological element known as "snow depth", perhaps not particularly used but certainly useful...  Climatologically it is recorded at observation time in most locations (so that usually means the morning), while airports report it at 12UTC (7AM EST, 6AM MST, etc).  It wouldn't necessarily capture the greatest depth, but certainly gives you an idea about how much melting was involved.

[Clinch Leatherwood]

It sure does make sense since that fallen total of 9" never lived on the ground all at once. Case in point, my Jan 26-27 2010 total of 17.3" would likely be around 15" since two inches of round one were lost due to mixing issues for several hours that day depending on the interval.

 

 

Snow totals have been greatly inflated over the last decade IMO.  This should correct all of that, they want to see what's OTG which for the most part is how I've always measured anyway.   Back in the 70s and 80s...when we measured we measured new snow OTG at the end of the storm.  If the Blizzard of 78 happened now everyone would have had 50-60" prior to this change.

 

JMHO.

[famartin]

Snow totals have been greatly inflated over the last decade IMO.  This should correct all of that, they want to see what's OTG which for the most part is how I've always measured anyway.   Back in the 70s and 80s...when we measured we measured new snow OTG at the end of the storm.  If the Blizzard of 78 happened now everyone would have had 50-60" prior to this change.

 

JMHO.

Is there a particular location or storm you are thinking of for having inflation?   Some comparisons can be made.  Though I don't think they track snow depth at Logan any longer, unfortunately.

[RCNYILWX]

Not sure how much this is going to change things because from my understanding, most of the COOP observers for the office I work for (LOT) only report the next morning anyway and hadnt been using the board clearing method. Unless CoCoRaHS observers are being told not to provide significant weather reports during an event, I presume we'll continue to receive those and we'll also continue to receive reports from spotters, trained or otherwise, during an event, that aren't following this new "improved" standard. With that being said though, it's an unfortunate change for the COOP sites, (I know of only 1 out here) that were providing 6 hour board clearing info during an event, because if it snowed 4" and 2" melted or compacted, it still snowed 4". Ray mentioned that NWS offices will still be using the board clearing method, but how about the offices that are also COOP sites?

[famartin]

Not sure how much this is going to change things because from my understanding, most of the COOP observers for the office I work for (LOT) only report the next morning anyway and hadnt been using the board clearing method. Unless CoCoRaHS observers are being told not to provide significant weather reports during an event, I presume we'll continue to receive those and we'll also continue to receive reports from spotters, trained or otherwise, during an event, that aren't following this new "improved" standard. With that being said though, it's an unfortunate change for the COOP sites, (I know of only 1 out here) that were providing 6 hour board clearing info during an event, because if it snowed 4" and 2" melted or compacted, it still snowed 4". Ray mentioned that NWS offices will still be using the board clearing method, but how about the offices that are also COOP sites?

Any site which has been ordered to provide 6-hour measurements (COOP observers that provide snowfall for airports, contract weather observers, and WFO's (including COOP WFO's)) will still do it that way.  The previous guidelines allowed anyone to do the 6-hour method; the new guidelines restrict them to only those few sites authorized to do so.

 

Yes, in cases where snow falls, melts and falls again, such as storms with change-overs or significant breaks (we get those a lot here), snowfall totals may decrease.

[RCNYILWX]

Not sure how much this is going to change things because from my understanding, most of the COOP observers for the office I work for (LOT) only report the next morning anyway and hadnt been using the board clearing method. Unless CoCoRaHS observers are being told not to provide significant weather reports during an event, I presume we'll continue to receive those and we'll also continue to receive reports from spotters, trained or otherwise, during an event, that aren't following this new "improved" standard. With that being said though, it's an unfortunate change for the COOP sites, (I know of only 1 out here) that were providing 6 hour board clearing info during an event, because if it snowed 4" and 2" melted or compacted, it still snowed 4". Ray mentioned that NWS offices will still be using the board clearing method, but how about the offices that are also COOP sites?

Any site which has been ordered to provide 6-hour measurements (COOP observers that provide snowfall for airports, contract weather observers, and WFO's (including COOP WFO's)) will still do it that way.  The previous guidelines allowed anyone to do the 6-hour method; the new guidelines restrict them to only those few sites authorized to do so.

 

Yes, in cases where snow falls, melts and falls again, such as storms with change-overs or significant breaks (we get those a lot here), snowfall totals may decrease.

Ok thanks that's what I figured since the observational program leader here hadn't mentioned any changes to how we measure. It probably won't impact the one COOP I know of that used the board clearing method either because he's recognized as the official observer for Chicago Midway airport.

Sent from my SCH-I535 using Tapatalk

[famartin]

Ok thanks that's what I figured since the observational program leader here hadn't mentioned any changes to how we measure. It probably won't impact the one COOP I know of that used the board clearing method either because he's recognized as the official observer for Chicago Midway airport.

Sent from my SCH-I535

I've perused his records, he does a really good job.

[masomenos]

To get my snowfall totals over the years I've always averaged out the 6 hour board clearing method with the 24 hr method. Works nicely for me--especially those high ratio events that can get a bit out of control.

[powderfreak]

Snow totals have been greatly inflated over the last decade IMO. This should correct all of that, they want to see what's OTG which for the most part is how I've always measured anyway. Back in the 70s and 80s...when we measured we measured new snow OTG at the end of the storm. If the Blizzard of 78 happened now everyone would have had 50-60" prior to this change.

JMHO.

I look at snowfall and snow depth as two seperate things...it seems essentially they want to measure snow depth or change in snow depth almost.

We've been talking about it in the NNE thread... But say a 24 hour storm hits, 7am to 7am for sake of ease. There was no snow on the ground prior to the storm. The sum of the 6 hourly measurements is 18.5". The depth at the end of the 24 hours is 15".

You then report that new snowfall is 18.5" and snow depth is 15". It's not that hard. I'm not sure why they don't use the snow depth more often...snowfall is a measurement of what comes out of the sky, not necessarily what lays on the ground for x-period of time.

The whole not being able to measure snow that melts and the re-accumulates is ridiculous. Tell that to the plow driver who cleared 6" of wet snow in the morning, then goes back that night and clears another 6"...meanwhile the report says only 8" fell because 4" melted during the afternoon change to rain. That's like measuring precipitation but saying you can't count it if it falls from the sky as anything but rain.

[powderfreak]

To get my snowfall totals over the years I've always averaged out the 6 hour board clearing method with the 24 hr method. Works nicely for me--especially those high ratio events that can get a bit out of control.

I think it's important to just say how you are measuring it...now you've got the good observers who do every 6 hours can't compare their new data to the old.

Take J.Spin in the NNE thread. He measures every 6-hours for COCORAHS (snowfall and liquid), and averages 160" a year at 500ft elevation. He has really well documented data, and even a web cam set up so he can always remotely get the snow at its deepest depth like you are supposed to prior to settling. He's a man of science. And he'll even say in the notes for example that during upslope fluff storms that the snowboard got 6" in 6 hours, but depth only increased 2" because it's settling that fast.

He's VT-WS-19 and one of the best VT observers...the only one that will religiously be out there every 6 hours.

If he switches over to once every 24 hours, the last 6-7 years of data are useless because it's comparing apples to oranges.

[famartin]

I think it's important to just say how you are measuring it...now you've got the good observers who do every 6 hours can't compare their new data to the old.

Take J.Spin in the NNE thread. He measures every 6-hours for COCORAHS (snowfall and liquid), and averages 160" a year at 500ft elevation. He has really well documented data, and even a web cam set up so he can always remotely get the snow at its deepest depth like you are supposed to prior to settling. He's a man of science. And he'll even say in the notes for example that during upslope fluff storms that the snowboard got 6" in 6 hours, but depth only increased 2" because it's settling that fast.

He's VT-WS-19 and one of the best VT observers...the only one that will religiously be out there every 6 hours.

If he switches over to once every 24 hours, the last 6-7 years of data are useless because it's comparing apples to oranges.

 

That last part is part of why the 6-hour measurements are now forbidden for all except the select few.

[famartin]

I think it's important to just say how you are measuring it...now you've got the good observers who do every 6 hours can't compare their new data to the old.

Take J.Spin in the NNE thread. He measures every 6-hours for COCORAHS (snowfall and liquid), and averages 160" a year at 500ft elevation. He has really well documented data, and even a web cam set up so he can always remotely get the snow at its deepest depth like you are supposed to prior to settling. He's a man of science. And he'll even say in the notes for example that during upslope fluff storms that the snowboard got 6" in 6 hours, but depth only increased 2" because it's settling that fast.

He's VT-WS-19 and one of the best VT observers...the only one that will religiously be out there every 6 hours.

If he switches over to once every 24 hours, the last 6-7 years of data are useless because it's comparing apples to oranges.

 

BTW, I'm curious how he sets up his board.  Its my belief, personally, that the biggest cause of snowfall inflation is improper board placement, either in a place that drifts/blows excessive snowfall onto the board, or placing the board back in the same snow hole it just came out of.  I have no studies to back that up, hence my question about his board placement.

[powderfreak]

BTW, I'm curious how he sets up his board. Its my belief, personally, that the biggest cause of snowfall inflation is improper board placement, either in a place that drifts/blows excessive snowfall onto the board, or placing the board back in the same snow hole it just came out of. I have no studies to back that up, hence my question about his board placement.

His set up very good. I know the general area he is in and it's very sheltered by terrain so he gets next to no wind, and can build some incredible loft in snowfalls.

Here's his set up:

http://jandeproductions.com/snowfall.html

And here are his observations:

http://jandeproductions.com/weather.html

The elevated snow board means he never has any issue with placing it in a hole or something...just clear it and tally the next 6 hours.

[powderfreak]

That last part is part of why the 6-hour measurements are now forbidden for all except the select few.

I'm not sure I follow. So the reason why the 6-hr deal was scrapped was because not everyone is doing it? So they are dumbing it down to make it easier to compare with the lazy observers?

It just seems like they want snow depth and change in snow depth instead of snowfall.

[LakeEffectKing]

This revised method will really impact LES event totals...if one adheres to such a method. During very heavy snowfall rates (>4"/hr.) and with the sometimes insane ratios (40:1 or higher), the settling rates can easily run in excess of 2"/hr. if such rates continued for longer than 12 hours.

Back in the '90's I assisited NWS BUF in a snowfall measurement experiment during an intense 18 hr. LES event up in the Tug Hill region, with over 40 snowboards in a sheltered field with differing measuring times (little wind). While lots and lots of data was gathered, the take home message was that snowfall measuring is highly subjective, and the varying aspects that go into a "true" unified measuring technique for ALL events (synoptic, wet, windy, LES, mixing, etc.) is not plausable in a "scientific" way.

For public consumption, the best we can offer is really the "highest total measured" while the event is ongoing. But even that is subjective, as (esp. with LES) you can snow very heavily for hours....have a 3,8,12, or longer hour break, then have it snow hard again for "xx" hours.

BTW, in the experiment I mentioned above, the board that was never cleared during the event measured 25" as the event ended. The "clear every 6 hour" board was 12+9+11=32", which was the "official total." 12 hours later the snow on the "never cleared board had settled to 18" under sunny, very light wind conditions.

[dendrite]

This revised method will really impact LES event totals...if one adheres to such a method. During very heavy snowfall rates (>4"/hr.) and with the sometimes insane ratios (40:1 or higher), the settling rates can easily run in excess of 2"/hr. if such rates continued for longer than 12 hours.Back in the '90's I assisited NWS BUF in a snowfall measurement experiment during an intense 18 hr. LES event up in the Tug Hill region, with over 40 snowboards in a sheltered field with differing measuring times (little wind). While lots and lots of data was gathered, the take home message was that snowfall measuring is highly subjective, and the varying aspects that go into a "true" unified measuring technique for ALL events (synoptic, wet, windy, LES, mixing, etc.) is not plausable in a "scientific" way.For public consumption, the best we can offer is really the "highest total measured" while the event is ongoing. But even that is subjective, as (esp. with LES) you can snow very heavily for hours....have a 3,8,12, or long hour break, then have it snow hard again for "xx" hours.BTW, in the experiment I mentioned above, the board that was never cleared during the event measured 25" as the event ended. The "clear every 6 hour" board was 12+9+11=32", which was the "official total." 12 hours later the snow on the "never cleared board had settled to 18" under sunny, very light wind conditions.

Beat me to it. That insane BUF LES storm from over a decade ago featured about 80" of new snow, but the depth never got over the low 40s IIRC. They were racking up over 1"/hr at the ASOS with the depth steady or slowly falling...lol. So technically all of those hours featured 0" snow, but try telling that to the road crews that clear the roads a few times per day.

[isohume]

This wont impact inherent snowfall measurement error from a climo prespective. The few six hr/ly reporters will continue with their practice, while the vast majority "bad" COOP observers will continue with their practice since they don't measure 6 hr/ly SF in the first place. They ("bad" observers) measure once a day at ob time. If anything, it may make it less confusing to the COOP observer and we'll actually get more SF reported.  

[famartin]

This wont impact inherent snowfall measurement error from a climo prespective. The few six hr/ly reporters will continue with their practice, while the vast majority "bad" COOP observers will continue with their practice since they didn't report 6 hr/ly SF in the first place. They ("bad" observers) measure once a day at ob time. If anything, it may make it less confusing to the COOP observer and we'll actually get more SF reported.  

 

"Impact" will depend on how the observer has been measuring versus how they are going to measure now. 

 

I don't think there will be any difference in number of SF reports.  Some people care, many still won't. 

[isohume]

"Impact" will depend on how the observer has been measuring versus how they are going to measure now. 

 

I don't think there will be any difference in number of SF reports.  Some people care, many still won't. 

 

That's what it will boil down to with COOP observers I'm sure. They can't observe every 6 hrs anyway due to work, life, sleep, etc, which is more than reasonable. They are not "bad" observers, hence the reason I used the quotes.  The LCD observers for official CLI and others will still be required to measure 6 hr/ly. I see no appreciable new error amount added to or subtracted from the climate record. 

[powderfreak]

Beat me to it. That insane BUF LES storm from over a decade ago featured about 80" of new snow, but the depth never got over the low 40s IIRC. They were racking up over 1"/hr at the ASOS with the depth steady or slowly falling...lol. So technically all of those hours featured 0" snow, but try telling that to the road crews that clear the roads a few times per day.

That happens during the big upslope events, too. There's a NWS employee from BTV in Underhill, VT that is meticulous with snowfall it seems from the observations, and it's not uncommon to see during big upslope with 40:1 ratios, like 30"+ of snowfall but a depth of like 24".

And I know JSpin has noted those times when he's getting 6"+ on the board but snow depth only goes up 2". Your point about trying to tell road crews or drivers who are out in 1/4sm +SN that's falling 1"/hr or more, that only 2" fell in 6 hours because that was the change in depth, is a good one.

[Absolute Humidity]

So do we say: "Snowfall will be heavy today with negative accumulations." Before LES and up-sloping events?

[michsnowfreak]

Im sure most observers will continue with their regular measuring techniques. That said, these new guidelines have surpassed Weather Channel level of stupidity. I cant even fathom that they actually meant to type it out how ridiculous it sounds. The funny thing is, Ive always thought the problem with many coop observers is LOWBALLING snowfall, not inflation, because they look at their boards at morning obs time and whats there is there, with zero accounting for settling. Ive always though the biggest problems from inflation came from the random reports from non-coop observers when John Q. Public who takes his rules out during a snowstorm, and calls the number in. John Q. is not a coop observer anyway, so he wont even see these guidelines lol.

 

Having two different sets of rules...clear the board every 6 hours at first order and paid coop stations, but not at other ones....is just plain stupid. Are they TRYING to make it seem like it snows less than it does, or simply create bigger discrepancies?

 

In Oct I was emailed snow measuring reminders from the NWS, and it was the previous guidelines pdf document (before this one was updated in September). Regarding when multiple snow events happen in a 24 hour period....An example from the NWS guidelines If 3 seperate snow squalls affected you during the 24 hour period, 3.0, 2.2, and 1.5" fell, but each melted completely in between, your obs the next day would read 6.7" new snow, depth 0. Thats obviously a very unlikely scenario lol, but the point is, snow is going to melt and settle (dramatically so in lake effect situations at times). Obviously all first order stations must follow the 6-hour measurment guidelines. In this new version, first it says that if the snow event ends well before the 24 hour period, measure the snow as soon as possible. Then, in total contradictory fashion, it says no matter how often it snows in a 24 hour period, report only the single highest snowfall on the board. That basically renders the entire point of the 14 page guide as useless. 

 

So according to this, scenario, lets say my obs time is 8am. A waa snowstorm rolls through, lasting from 9am to 2pm. The storm drops a quick 4.3" of snow, then a powerful warm front rolls through, temps torch, and the snow melts completely. During the overnight hours, the brief torch ends and a cold front rolls though and a dusting of 0.3" snow falls. When making the 8am obs, obviously the correct procedure would be to report 4.6" snowfall and a T of snow depth. However, according to this idiotic scenario, I shall report 0.3" snowfall and T depth.   Report ONLY the greatest single snow amount on the snow board no matter how many times it snows????   But wait...they also contradictoraly said measure as soon as the snow stops. So then I would have measured 4.3" at 2pm the previous day. SOOO......according to this, if that storm rolled through, and there was no cold front and subsequent dusting, just continued torching, I would report 4.3" snow, 0 depth the next morning at 8am. But since there was multiple snowfall periods, I can only report whats greatest on the snowboard at obs time. So if that 0.3" dusting forces me to lose the previous 4.3" of snow as if it never happened?   Terrible, terrible, TERRIBLE wording for measuring multiple snow events.

 

I know that isnt the intention, and is certainly not what any NWS wants or expects, but obviously what this new thing is doing is seemingly rewarding the "bad" observers and saying, fine, you always simply go by whats on your board at morning obs time regardless of how many times we have sent you the reminders, so we will just change the wording to match your practices. Bottom line, the "bad" snow observers will not change their ways, nor will the "good" ones who follow the 6 hour procedures.

 

These are actual copy an pastes from section 3 of the guidelines list. Wow, just wow. Can you say CONTRADICTION!????

 

For example: Snow begins to fall at 10:00 a.m., accumulates to 4.2

inches by 3:00 p.m and then stops Ideally, this is when you should measure the snow

The snow begins melting and settling such that by your observation the next morning you only have 2.6 inches

of snow on your snowboard The correct number to report for your 24hour snowfall

is 4.2 inches the accumulation prior to melting and settling.

 

Due to work or other commitments you may not be available to measure snow when it ends or

before your regular observation time In these cases use your best estimate, based on a

measurement of snowfall at the time of observation along with knowledge of what took place in

the last 24 hours Input may be obtained from other people who were near the station during the snow event

 

If the snow event ends well before the end of the 24 hour observing period make the 24

hour measurement at the end of the snowevent, if possible For example if the snow event ends at

1PM, make the snowfall measurement at that time If snow falls later in the 24 hour period an additional measurement can be made but report only the largest accumulated snowfall total No matter how many

times it snows during the 24hour period report only the SINGLE highest snowfall amount

that accumulated on the SMB. Only clear the snowboard at the end of the 24hour observing

period. If you cannot take a measurement at the end of the snow event, measure it as soon as

possible after the event ends and no later than the official observation time.

 

 

Theres a youtube series of snow measuring shorts

https://www.youtube....0q_zodgCz-etYB5

[michsnowfreak]

Any site which has been ordered to provide 6-hour measurements (COOP observers that provide snowfall for airports, contract weather observers, and WFO's (including COOP WFO's)) will still do it that way.  The previous guidelines allowed anyone to do the 6-hour method; the new guidelines restrict them to only those few sites authorized to do so.

 

Yes, in cases where snow falls, melts and falls again, such as storms with change-overs or significant breaks (we get those a lot here), snowfall totals may decrease.

Well I will certainly continue the 6 hr rule imby.

 

Thats another thing....the airport observers are reporting totals every 6 hours anyway. Whether the coop observer measured every 6 hours, every hour, or just once in a 24-hour period not accounting for any melting or settling....no one really knows as its simply what they phone in at 7am. They are the only ones that know how they measure, because whether or not they cleared every 6 hours, they didnt report it in as such. Rather, just one 24-hour snowfall total and the obs time snow depth.

 

Does whoever updated these "guidelines" think that anyone (the "good" or "bad" snow observers) will change their ways anyway? Snow is hard enough to measure as it is...lets complicate it further lol.

[michsnowfreak]

The biggest impact will be on those (probably few) COOPs which do do 6-hour measurements; they may now report lower.  The other impact will be on those events with change-overs, or multiple snowfalls in a 24-hour period with melting in between; those events will get lowered measurements compared to previously.  At least at those COOPs with conscientious snowfall observers.  Like I said, many don't have them.

I lol'd when you said about the 2"+2"=2" example above, that adding it to 4" is now "forbidden". I have to imagine VERY few will be changing their snow measuring techniques (I also venture most will not even SEE these ridiculous new guidelines).

 

Also..its way different here in the Great Lakes when its snowing so frequently. Rarely does a storm sweep in, snow like hell for XX hours, then clear up as is often the case on the east coast. Living in a place like that, I dont see a problem measuring right when the storm is completed, even if it lasted more than 6 hours (unless rain is falling for a period in mid-storm or something like that). Its usually a different story here.

 

The bottom line to all of it is, whether or not many will be following these new guidelines (my money is on not), it just is wrong on so many levels. And the fact that the official sites still do the 6-hour method (which I believe is correct) but they want coops to not, is even more ascinine. Its like a boss telling employee #1 they get an hour lunch but employee #2 they get a 30-minute lunch, and both do the same job.

 

Do you know how long the 6 hour rule has been in place?

[famartin]

Im sure most observers will continue with their regular measuring techniques. That said, these new guidelines have surpassed Weather Channel level of stupidity. I cant even fathom that they actually meant to type it out how ridiculous it sounds. The funny thing is, Ive always thought the problem with many coop observers is LOWBALLING snowfall, not inflation, because they look at their boards at morning obs time and whats there is there, with zero accounting for settling. Ive always though the biggest problems from inflation came from the random reports from non-coop observers when John Q. Public who takes his rules out during a snowstorm, and calls the number in. John Q. is not a coop observer anyway, so he wont even see these guidelines lol.

 

For consistency between sites, they want EVERYONE to "lowball" it.

[famartin]

So according to this, scenario, lets say my obs time is 8am. A waa snowstorm rolls through, lasting from 9am to 2pm. The storm drops a quick 4.3" of snow, then a powerful warm front rolls through, temps torch, and the snow melts completely. During the overnight hours, the brief torch ends and a cold front rolls though and a dusting of 0.3" snow falls. When making the 8am obs, obviously the correct procedure would be to report 4.6" snowfall and a T of snow depth. However, according to this idiotic scenario, I shall report 0.3" snowfall and T depth.   Report ONLY the greatest single snow amount on the snow board no matter how many times it snows????   But wait...they also contradictoraly said measure as soon as the snow stops. So then I would have measured 4.3" at 2pm the previous day. SOOO......according to this, if that storm rolled through, and there was no cold front and subsequent dusting, just continued torching, I would report 4.3" snow, 0 depth the next morning at 8am. But since there was multiple snowfall periods, I can only report whats greatest on the snowboard at obs time. So if that 0.3" dusting forces me to lose the previous 4.3" of snow as if it never happened?   Terrible, terrible, TERRIBLE wording for measuring multiple snow events.

 

I know that isnt the intention, and is certainly not what any NWS wants or expects, but obviously what this new thing is doing is seemingly rewarding the "bad" observers and saying, fine, you always simply go by whats on your board at morning obs time regardless of how many times we have sent you the reminders, so we will just change the wording to match your practices. Bottom line, the "bad" snow observers will not change their ways, nor will the "good" ones who follow the 6 hour procedures.

I was told that it was felt that the old guidelines gave too much weight to small snowfalls like that, and the new ones would reduce their effect.

[Amped]

Probably the most significant change is the elimination of clearing your board every 6 hours during snow fall. Instead the new guidelines want everyone to only measure the total depth every six hours and to report your maximum depth (within a 24 hr period) at the end of said 24 hr period. So no more board cleaning every 6 hrs. They feel this has a tendency to inflate totals as I agree.

Oh good, maybe I won't see 20+ totals all around me when I measure 14"

[famartin]

Do you know how long the 6 hour rule has been in place?

 

The 6-hour measurements have been done for 100+ years.

 

However, I do not know if snow boards were always cleared the way they are now.  That part is unclear in the historical record.  There are a few guys on here who used to observe at airports in the 80s, like Rainshadow, who could tell you exactly what they did back then.

[masomenos]

I think it's important to just say how you are measuring it...now you've got the good observers who do every 6 hours can't compare their new data to the old.

Take J.Spin in the NNE thread. He measures every 6-hours for COCORAHS (snowfall and liquid), and averages 160" a year at 500ft elevation. He has really well documented data, and even a web cam set up so he can always remotely get the snow at its deepest depth like you are supposed to prior to settling. He's a man of science. And he'll even say in the notes for example that during upslope fluff storms that the snowboard got 6" in 6 hours, but depth only increased 2" because it's settling that fast.

He's VT-WS-19 and one of the best VT observers...the only one that will religiously be out there every 6 hours.

If he switches over to once every 24 hours, the last 6-7 years of data are useless because it's comparing apples to oranges.

Yup, certainly does. Consistency is key when it comes to observations, or the data is more or less useless. IMO, the measuring technique that best reflects a snowfall's impact on society is the measuring technique that should be implemented. Makes no sense that one measuring method works for the NWS, but not for all spotters/co-ops as a whole. This really isn't complicated stuff...anybody with half a brain can properly utilize the 6hr method.

 

For me personally, as a record keeper, I like to be on the conservative side when it comes to measuring snow, but even the 24 hr method seems to have little value in conveying the impact of a snowstorm to the public. After all, it's not really the first rate NWS observer sites that you see in snowfall reports in the media...it's from spotters/co-ops and other everyday folk that make up the vast majority of reported snowfall totals.