OBS/DISCO - The Historic James Blizzard of 2022

[IowaStorm05]

4 hours ago, JC-CT said:

@The 4 SeasonsAppreciate you taking the time to talk to me and try to figure out my outlier report before putting together the map, and of course the fact that you took me at my word for what I reported. I took a little deeper dive into the cocorahs numbers this afternoon, and unless I'm badly misinterpreting the data, my (and @IowaStorm05's) measurements don't look that crazy after all when you account for the fact that we didn't do 6 hour clears but measured new snow depth after it was winding down. I did remeasure in the morning on 1/30 and still had 9" new plus the 1" glacier layer I went into it with. Seems all of the bigger totals in Tolland County were doing at a minimum 24 hour clears which would have caught the first 6 hours of the storm, but more likely they were mostly all 6 hour clears (one of the stations, Willington, even had 1.5" less OTG on 1/30 at 7am than they reported as new for just the previous 24 hours, which of course didn't include early AM on 1/29 - so it couldn't have even been a 24 hour clear). The Willington station does seem to be a reliable daily reporter, reporting depths of 11.0" on the mornings of both 1/30 and 1/31, then 9.0", 8.5", and 5.5" through this morning (OUCH).

So either I had an extremely low ratio 9" that was comparable in LE to whatever fell to my north/northeast, or probably more likely is that my report is understated vs had I measured and cleared the board every 6 hours. I always thought that clearing the board only made a small difference (<1") unless snowfall totals started to get way up there or in super fluffy snow, but that doesn't seem to be the case here. I also thought that NWS & cocorahs guidelines were to not clear until the end of a storm (unless you are an airport) but it seems like clearing might still be the norm.

There were, however, a cluster of measurements from the Somers area between 9"-10" that all appear to be final OTG measurements (OTG = new accumulation). The 8.0"s from Rocky Hill and East Hartford also appear to be final OTG measurements. The station that reported 13.8" in Manchester reported both 3.8" new and 3.8" OTG as of 7am on 1/29, and reported 10.0" new at 7am on 1/30 but did not include an OTG depth in that report, and they have not reported since. Point being, I'm not convinced there was quite as severe a cutoff there as was highlighted, for example between that 13.8" and the 8" in East Hartford, although there was definitely a gradient until you got into that secondary morning band over the Southington area. Seems like at least a factor in the variances in reporting may have been measuring/reporting method.

Curious to hear your (or anyone's) thoughts on this, as I'm very confident in my measurement for new snow depth as of the morning of 1/30 at approximately 9" new, 10" total depth, of dry but dense snow.

 

OTG Snow Depth 1/30:

 

This looks exact to me for my location at my Frog Bridge parking lot. I can report that on Fri 1/28 at 7am we would have 1 inch of crusty snow on NORTH sides of buildings but it was pretty spotty. The 1/7/22 snow lingered. Storm total was 9" and that all looks right. Part of me wonders if SE CT had a modest screw zone for the James Blizzard that hugged my route to and from work. RT 32 from my parking lot down to Franklin then down 395 to 95 at East Lyme seems to have had I would say a maximum of about 13 inches at its greatest. There were big drifts but I Cannot fathom any 17-20 inch totals anywhere there, and I believe that this entire area was just west of the best death bands, or that they were in the death bands as I saw on Radar, but strong winds blew the material to the east and it was not replaced from the lighter west.