Jump to content
  • Member Statistics

    17,608
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Two devastating graphs for D.C. snow lovers


capitalweather

Recommended Posts

Thought folks here would appreciate hate this:

http://www.washingto...SxOwO_blog.html

i was going to bust your chops a bit over revealing the discovery that Nina/+NAO is bad for us....but that chart is super cool...very good work by the NWS.....still doesn't erase the fact that they put us in a 5-9" WSW on the cusp of 12/26/10 when it was obvious to everyone that it was going to be a total epic failure Snorkle.gif

Link to comment
Share on other sites

Hard to fight facts

Yup. There is constant discussion of pattern change from various quarters, but it's telling that this is constantly be pushed back. First it was mid-November, then it was around Thanksgiving, then after Thanksgiving, then the first week of December, then the week of Christmas, then the middle of January, etc, etc. That's usually a pretty good sign that winter, when it does arrive, isn't going to be great for snow-lovers and weenies.

At this point, any snow we get this winter will be a bonus. My bigger concern is that we end up with the pattern turning just as we get into the spring, which bums me out more than the lack of winter snow.

Silly that my best snow so far this season was in October!

Link to comment
Share on other sites

Yup. There is constant discussion of pattern change from various quarters, but it's telling that this is constantly be pushed back. First it was mid-November, then it was around Thanksgiving, then after Thanksgiving, then the first week of December, then the week of Christmas, then the middle of January, etc, etc. That's usually a pretty good sign that winter, when it does arrive, isn't going to be great for snow-lovers and weenies.

At this point, any snow we get this winter will be a bonus. My bigger concern is that we end up with the pattern turning just as we get into the spring, which bums me out more than the lack of winter snow.

Silly that my best snow so far this season was in October!

You and most of everyone here.

Link to comment
Share on other sites

So DCA has a 15.5" normal annual snowfall, however the median is 12.2". . So clearly, we have below normal snowfall winters a greater percentage of the time than we have above normal winters. The CWG graph shows that our percentage chances of being below normal in a nina winter is 14/21 = 66%. It appears we've only had 22 winters above the norm since 1950. That means our chances of having below normal winter in general is 38/60 = 63%. That means our chances of having a below normal winter in a nina is only 3% greater (66%-63%) than our winter expectations at DCA without regard for nino/nina. Perhaps nina doesn't have as much of a profound impact on our statistical chances of an above normal winter as it appears.

The second graph, however, is what kills it, the la nina coupled with the positive AO is clearly a deadly combination for snowlovers. Nice work. Personally, I believe the AO/NAO is of much greater impact on our winters than la ninas.

Thanks.

Link to comment
Share on other sites

So DCA has a 15.5" normal annual snowfall, however the median is 12.2". . So clearly, we have below normal snowfall winters a greater percentage of the time than we have above normal winters. The CWG graph shows that our percentage chances of being below normal in a nina winter is 14/21 = 66%. It appears we've only had 22 winters above the norm since 1950. That means our chances of having below normal winter in general is 38/60 = 63%. That means our chances of having a below normal winter in a nina is only 3% greater (66%-63%) than our winter expectations at DCA without regard for nino/nina. Perhaps nina doesn't have as much of a profound impact on our statistical chances of an above normal winter as it appears.

The second graph, however, is what kills it, the la nina coupled with the positive AO is clearly a deadly combination for snowlovers. Nice work. Personally, I believe the AO/NAO is of much greater impact on our winters than la ninas.

Thanks.

Interesting stats. That said, I think you are comparing Nina winters to all winters. The problem with that is "all winters" includes Nina winters - so the Nina winters pull up the percentage of below average snowfall.. To truly see the impact of Nina, compare Nina winters to all non-Nina winters.

Looking at the stats, I actually see, 15/21 = 71% of Nina winters near or below average. If we take Ninas out of the "all winters" column we are left with 23/39 = 59% of non-Nina winters near or below average.

So even correcting the stats.. it is still pretty grim. Bottom line - this is not a good snow town but we already knew that smile.png. I think it's safe to say Nina doesn't help, but it isn't the end all and be all. The massive +AO, however, is. Until that changes we won't get much of anything.

Link to comment
Share on other sites

Interesting stats. That said, I think you are comparing Nina winters to all winters. The problem with that is "all winters" includes Nina winters - so the Nina winters pull up the percentage of below average snowfall.. To truly see the impact of Nina, compare Nina winters to all non-Nina winters.

Looking at the stats, I actually see, 15/21 = 71% of Nina winters near or below average. If we take Ninas out of the "all winters" column we are left with 23/39 = 59% of non-Nina winters near or below average.

So even correcting the stats.. it is still pretty grim. Bottom line - this is not a good snow town but we already knew that smile.png. I think it's safe to say Nina doesn't help, but it isn't the end all and be all. The massive +AO, however, is. Until that changes we won't get much of anything.

Yeah I can agree with that. Still, that means roughly 6 of 10 non-nina winters are below average and 7 of 10 are below average in ninas. So over a 10 year period it's only one more year of below normal snowfall in nina vs. non-nina. I have to imagine you will find a much more profound statistical effect of the AO being positive vs. negative on our probability of above normal winters.

In fact - I looked back at the state of the AO for Dec/Jan/Feb for every winter that DCA had above normal snow. Every single one of those winters featured at least one month with a negative AO, and the overwhelming majority had 2 or even 3 months of a negative AO. Fact is, there has never been an above normal snowfall winter at DCA without at least one of the core winter months featuring a negative AO. I like our chances if we get a negative AO January and/or Feb. - even in a nina.

Link to comment
Share on other sites

It does look crappy for snow. Hard to argue with that. The period between Christmas and New Years has held my interest for a while. Nice spike in the pna and a slightly better looking atlantic. Looks like energy moves both underneath and over the top of the ridge at various times. Several transient cold shots as well.

No reason to believe that there is no chance of getting the timing right for something. Low to no chance at a decent event but we could pull off a 1-3" if the ingredients come together. I'll be in Manhattan from the 28th - 1st visiting family so I won't be bummed if something misses dc to the north during that time.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...