Mid Atlantic Snow totals thread for winter 2013/14

[mappy]

That's not how to measure

I'm convinced most ppl don't know how to measure. Anyone who says "I'm eyeballing 5 inches", I'm calling a liar

[I-83 BLIZZARD]

1.5 inches of sleet and snow last night. Hope it is it for the season!

[ravensrule]

12/8/13 5.2"
12/10/13 2.6"
12/14/13 1.3"
12/26/13 0.4"
1/2/14 7.3"
1/21/14 9.2"
1/25/14 0.4"
2/3/14 0.8"
2/9/14 1.2"
2/12-13/14 21"
2/18/14 1.2"

2/25/14  0.5"

2/26/14  1.8"

3/3/14   3.5"

3/16-17/14 5.9"

3/25/14  1.0"

3/30/14  .7"

 

Total- 64.0"

[Sparky]

4" on 3/30

 

Monthly Summary:

Nov - .25

Dec - 15.75

Jan - 17.5

Feb - 32

Mar - 17.25

 

Total 82.75

 

Lat 39.54

Long  -76.98

 

Details:

11/27 - .25

12/8 - 8.75

12/10 - 4.25

12/14 - 2.25

12/17 - .25

12/26 - .25

1/2 - 6

1/18 - 0.5

1/21 - 10.75

1/28 - .25

2/3 - 2.5

2/9 - 1.5 

2/12-13 - 24.75

2/15 - .5

2/18 - 1.5

2/25 - .5

2/26 - .75

3/3 - 5.5

3/17 - 5.25

3/25 - 2.5

3/30 - 4

[mappy]

Matt,

Any idea what Randy should have now? His last update was 31.5, which is low for north DC, especially with Ian at 42 not too far from him.

I've got two other "low" numbers as well:

NorthArlington (member) at 37.8

Dalecaria Res at 36.1

Those two points and Randy, are keeping the 30-39 line much further north than your hand drawn map

[Deck Pic]

Matt,

Any idea what Randy should have now? His last update was 31.5, which is low for north DC, especially with Ian at 42 not too far from him.

I've got two other "low" numbers as well:

NorthArlington (member) at 37.8

Dalecaria Res at 36.1

Those two points and Randy, are keeping the 30-39 line much further north than your hand drawn map

 

Randy has nearly the same elevation as Ian, but is on the east side of the park and doesn't do quite as well.  I'd guess he is at 40-41".  Punt Dalecarla. They are around 40" for sure.  They don't measure every event and do poor measurements.  North Arlington is certainly over 40".  Though not sure exactly how much.  Keep in mind my map is just for DC proper.  The reason why the contour starts so close to the water is because there is immediate elevation once you get inland. I doubt the 40" line is any further north than this.  This is just for DC proper.  This puts Randy right on the 40" line.  I realize for the type of map you are doing you have to broad brush.  But this is probably a pretty good guide.  Spring Valley and Wesley Heights are near 400' which is why the contour starts so far southwest.  

 

[Deck Pic]

I'd guesstimate Randy's total as below in parentheses versus mine which would put him right on the 40" contour

 

12/8: 1.0" (1.25")

12/10: 0.5" (0.5")

1/2-3: 2.5" (3.25")

1/21: 4.5" (5.0")

1/28-29: 1.0" (0.75")

2/9: 0.25" (0.25")

2/12-13: 8.75" (10.0")

2/18: 0.5" (0.5")

2/25: 2.25" (2.25")

2/26: 1.25" (1.25")

3/3: 4.0" (4.25")

3/16-17: 7.75" (8.0")

3/25: 2.25" (2.5")

 

Total - 36.5" (39.75")

 

38.902543/-77.028075

[mappy]

Thanks, I'll PM you a screenshot of what I got, tho you'll have to empty your inbox a little

[Deck Pic]

Thanks, I'll PM you a screenshot of what I got, tho you'll have to empty your inbox a little

 

done. thanks

[ecosense]

I thought snow fall measurements were taken at intervals during the storm and each is added to get the total.  If you just measure the final depth you don't have a true total snow fall.  Just an accumulation that depending on other conditions can be greatly reduced from the total.  If not, how is snow fall to be measured?

[Deck Pic]

I thought snow fall measurements were taken at intervals during the storm and each is added to get the total.  If you just measure the final depth you don't have a true total snow fall.  Just an accumulation that depending on other conditions can be greatly reduced from the total.  If not, how is snow fall to be measured?

 

I don't know that we need to be measuring by some perfect rules, but you can't sweep a surface every 10 minutes...you can do it every 6 hours.  otherwise even in an ideal accumulating situation you will get inflated totals...for a slush fest like yesterday, the best way to measure is probably max depth...not accusing you of this, but we have to remember that snow totals are not a pissing contest...they are an accuracy contest...you dont get to become a spotter or observer by being the best or the biggest....sometimes you just have to stick a ruler in the ground (not grass) and take a measurement and use it, even if you think it is too low...

[ecosense]

I don't know where every ten minutes came from but I took three measurements during the event: 0.5"at 1820, 0.7" at 1930, and 1.1" at 2230.  Given the air temp. I thought it a more accurate method than sticking a ruler in the melted remains.  I'm still going with 2.3"  

[das]

Reports of 2.1" and 2.0" at three locations within 2 miles to the N, NE and S of me so I'll go with a storm total of 2.0" for yesterday.  

 

Season total is now 65.1"

39.14°N 77.16°W, Clarksburg, MD

[I-83 BLIZZARD]

I measured on a glass table, piece of plywood in the driveway, and a plastic table away from trees etc in yard this morning. Temp last night was 35 so it is possible I lost depth to compaction etc. but I think 1.5 is an accurate representation of ground truth by 6:00 am here. I take multiple measurements and average.

[gymengineer]

I don't know where every ten minutes came from but I took three measurements during the event: 0.5"at 1820, 0.7" at 1930, and 1.1" at 2230. Given the air temp. I thought it a more accurate method than sticking a ruler in the melted remains. I'm still going with 2.3"

What zwyts was alluding to is that there are "official" measuring guidelines that you can look up. So your method described here doesn't match how spotters and CoOp or Corcorahs observers are trained to measure.

[Ian]

I probably should include like .25" from yesterday but I never measured so I'll probably leave it out. 

[Deck Pic]

What zwyts was alluding to is that there are "official" measuring guidelines that you can look up. So your method described here doesn't match how spotters and CoOp or Corcorahs observers are trained to measure.

 

it is also more about the spirit of measuring in good faith...I am not saying he was disingenuous....but I generally think your snow total should be reasonably close to your max depth....Snow does compact and melt and we can't measure every 5 minutes, but if you record 2.3", you probably should have had close to 2" on the ground at some point

[NorthArlington101]

Matt,

Any idea what Randy should have now? His last update was 31.5, which is low for north DC, especially with Ian at 42 not too far from him.

I've got two other "low" numbers as well:

NorthArlington (member) at 37.8

Dalecaria Res at 36.1

Those two points and Randy, are keeping the 30-39 line much further north than your hand drawn map

You should probably just ignore my stats, I'm really pretty bad at measuring, and keeping track of it. I'm somewhere in the low forties, and that's the best I can do...

Sorry

[ecosense]

You do realize I'm measuring snow fall and not snow depth.  As per NOAA guidelines http://www.crh.noaa.gov/jkl/?n=snow_measurement .  And yes, snowfall can be significantly greater than snow depth which is effected by moisture levels, temperature both air and ground, density, drifting....   I was trying all winter to record snowfall so each event was handled in this repeatable fashion. I thought this was how everyone was measuring the snow. If I have made a meteorological faux-pas my bad.

[gymengineer]

You do realize I'm measuring snow fall and not snow depth.  As per NOAA guidelines http://www.crh.noaa.gov/jkl/?n=snow_measurement .  And yes, snowfall can be significantly greater than snow depth which is effected by moisture levels, temperature both air and ground, density, drifting....   I was trying all winter to record snowfall so each event was handled in this repeatable fashion. I thought this was how everyone was measuring the snow. If I have made a meteorological faux-pas my bad.

http://www.nws.noaa.gov/om/coop/reference/Snow_Measurement_Guidelines.pdf  -- especially pages 7-9

Your mistake was the frequency in clearing.

[WxMan1]

41.25" total, details in my sig below.  Is it safe to say that's going to be the final?

[TL97]

3/25- 1.5"

Season Total: 59"

3/31- 1.5"

Season Total: 60.5"

[Random Chaos]

I'll give my totals of 2-3" thanks to the wind blowing it all off. Of course, all of the big storms I got multi-foot drifts from the same wind, with one storm over 3' drifts.

 

Next year I hope for a nice no wind long duration snow

[Amped]

12/8/13:  7.5"

12/10/13:  3.5"

12/14/13:  1.5"

12/17/13:  T"
1/2/14:     5"

1/18/14:    T"

1/21/14:  8.5"

1/28/14:  0.5"

2/3/14:   2"

2/9/14:  1"

2/13/14:  18"

2/18/14:  1.0"

2/25/14: 0.25"

2/26/14: 0.25"

3/3/14:   4"

3/17/14: 6.0"

3/25/14: 2"

3/30/14: T

Total: 61"

[mappy]

You do realize I'm measuring snow fall and not snow depth.  As per NOAA guidelines http://www.crh.noaa.gov/jkl/?n=snow_measurement .  And yes, snowfall can be significantly greater than snow depth which is effected by moisture levels, temperature both air and ground, density, drifting....   I was trying all winter to record snowfall so each event was handled in this repeatable fashion. I thought this was how everyone was measuring the snow. If I have made a meteorological faux-pas my bad.

 

I'll keep your 70.8, since for your area it does make sense given everything around you is 70" or higher. But yes, how often you are clearing your snowboard isn't correct.

[WinterWxLuvr]

it is also more about the spirit of measuring in good faith...I am not saying he was disingenuous....but I generally think your snow total should be reasonably close to your max depth....Snow does compact and melt and we can't measure every 5 minutes, but if you record 2.3", you probably should have had close to 2" on the ground at some point

I generally agree with this, but I think for some storms, 6 hours is too long.  Having said that, I didn't clear my measuring spot any this year.  I'm just too lazy to do it.  I'm sticking a ruler in the snow and whatever it says, that's what it is.

[Deck Pic]

I generally agree with this, but I think for some storms, 6 hours is too long.  Having said that, I didn't clear my measuring spot any this year.  I'm just too lazy to do it.  I'm sticking a ruler in the snow and whatever it says, that's what it is.

 

I think just generally using max depth is fine here and maybe tack a little on for compaction/melting since you aren't measuring every 5 minutes....at some point ecosense probably had 1.5 or 2"

[wxdude64]

I generally agree with this, but I think for some storms, 6 hours is too long.  Having said that, I didn't clear my measuring spot any this year.  I'm just too lazy to do it.  I'm sticking a ruler in the snow and whatever it says, that's what it is.

 

 

I think just generally using max depth is fine here and maybe tack a little on for compaction/melting since you aren't measuring every 5 minutes....at some point ecosense probably had 1.5 or 2"

Didn't NWS change their measuring methods for Co-ops, etc this year? If I remember there is to be NO board clearing, only what the greatest depth in past 24 hours. I argued about this with someone due to 'invisible accumulations' and the fact it would destroy snow ratios values that would occur during upslope and or lake streamers where it'd snow 1 with .05 liquid, melt off then 2.3 with .15 liquid, mostly melt off then another 1 inch and 0.05 liquid. They want you to report only 2.3? Where'd the other 2 go?

Even worse, you now have 0.25 liquid on 2.3 inches of snow (9.2-1) instead of the 0.25 on 4.3 (17.2-1) ratio. Those two 0.05's don't disappear from your gauge just because the snow melted.   CoCoRaHS last I knew was still advocating the 6 hour snow clearing for boards.

 

EDIT- found the paragraph from NWS's snow measuring methods from Sept 2013-

3.1.3.

How to handle short events or multiple events in a 24-hour period

While acknowledging there is no perfect way of measuring snowfall, the following best practice accommodates the observer while ensuring the best consistency.

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 snow event, 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 24-hour period report only the

SINGLE highest snowfall amount that accumulated on the SMB.

Only clear the snowboard at the end of the 24-hour 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.

See Figure 1 as an example.

[nj2va]

Sorry MG, I went back and looked at my totals, and I added my individual events incorrectly.  I should be at 40" not 44" - sorry about that!

[mappy]

Ok, thanks!