Why, November?

2009-11-24 23:29:00.000 – Ryan Knapp,  Staff Meteorologist

Tonights view.

When I started my meteorology classes in fall of 1999, the general meteorology classes had about 100 students or so in them. As the second semester came about, that number was cut in about half. But it wasn’t until sophomore year that my peers started jumping ship left and right to engineering, computer science, physics or other majors. By the time I graduated, there was about seven of us, and that was considered a big class for my department. So why such a large drop off rate? Well, the answer I heard over and over again was how meteorology wasn’t what they thought it was. They chose meteorology because they thought it was going to be like what they saw on TV. In some ways it is but at the core of meteorology is a lot of math, physics, chemistry, and theory. And it wasn’t until the second year that all of these concentrations start to be used and students soon realize that it isn’t all green screens and giant L’s and H’s. But unfortunately, this (the TV weatherman persona) is the perception of a lot of people when they hear what I do for a living. But it isn’t as easy as it looks on TV.

If there was a magical weather formula where you plug in x and y and get z as the answer, I probably wouldn’t have a job. Although, forecasting kind has a formula feeling to it in that if I see certain characteristics, odds are we will get a certain outcome. But like high order math where if you forget to square one number, the outcome can be entirely different than expected. Did a high move faster blocking a low? Was there more moisture that models were indicating? It is a lot to look for with a lot of different outcomes. I like to think that overall we do a good job at forecasting and we have had a few interns look at our accuracy/precision. But it would be interesting to see if things have improved over my time here because I always try to learn from my mistakes. It’s similar to playing sports, the best way to get better for the future is to look at the mistakes of the past. It is all a matter of learning what certain weather patterns will do. But what about the current weather pattern we are in?

Since we only go out 36 hours on our higher summits forecast, I know what is causing today and tomorrow’s weather. I can use models out two weeks and get a general idea of what will happen but forecasting for an entire season is out of my realm. We keep getting emails asking us what is going to happen this winter and why November is acting so odd. I can explain what has caused the weather this month but as for what the coming months hold, I have to turn to National Weather Service, Accuweather, the Farmers Almanac, or one of several other websites as to what they are thinking since they have dedicated people who look at these sorts of things. So I am not very useful in looking ahead long term but I thought maybe I could look at our past for some clues that might explain what’s going on because the best way to know what the future might hold is to look at the past. So that is what I decided to do this past week.

Now, while Mount Washington Observatory has over 75 years of weather records, the World Meteorological Organization only considers a 30 year average to be a standard climatological normal (click here for more on why this is). So to save me a bit of time, I went with examining the past 30 years to hopefully find a pattern. I examined temperature, precipitation, and snowfall since these seem to be the big three we are getting the most questions about since they are the most obvious. I then looked at three factors that some have been suggesting: 1) Global warming because this is what most people are blaming for any weather now and days it seems. 2) El Nino and La Nina years since these have been circulating on the news recently since this is considered to be a El Nino year. And 3) is this is a result from the cool and very wet summer we had.

Now, I will start by saying that my “research” was very basic, very quick, and was by no means concrete or journal worthy. Due to my schedule, I maybe spent a total of three hours examining the data and weather maps which isn’t a lot of time to draw any sure fire conclusions. Plus, the month still has a week to go, so I don’t want to say November has thrown in the towel quite yet especially looking at models for this weekend. But I did debunk a few things and found an interesting correlation. To answer the first one, no, it is not global warming. Far from it. It is not the driest November in our history, that occurred in 1939 with only 2.31 inches. In fact it is not even in the top 10 driest Novembers. And out of the 30 past years, the top 10 driest Novembers are evenly spread with no distinct patterns. As for snowfall, it is not the least snowfall received since that too was in the 1930’s. Over the past 30 years it is currently the least snowiest but the month isn’t over and all it needs is 2 inches to pass that distinction, so still very plausible. As for warmth, it isn’t the warmest November ever nor is the warmest over the past 30 years. And there was no concrete warming trend in Novembers seen. So we are not getting noticeably warmer and drier in November because of global warming. Remember the correct term is climate change and the effects can only be seen over long periods of time; not days, weeks, months, or even 30 to 75 year periods. So please stop using global warming as the scapegoat.

As for El Nino and La Nina years, there was no correlation with these events in relation to temperature, precipitation or snowfall. These alter west coast weather patterns and indirectly affect the east coast but it isn’t as major as the affects are on southern California for example. In fact, over the past 30 years, some of our snowiest Novembers occurred with both El Nino and La Nina’s. So if anything, I would expect us to be wetter and snowier or at least closer to average.

But the last thing I looked at (wet summer=dry Nov.), I did find a small correlation for snowfall. In years where the months of June, July and August received nearly an inch or more of precipitation above the 30 year normal for all three months, November’s snowfall tended to be below the 30 year normal. In fact, for the 10 lowest years from the past 30 years, 7 out of 10 showed this correlation. But this wasn’t always the case and it isn’t something I would say is THE cause for what is going on in November. Given more time though (intern project in the future?) this would definitely be something worth looking into a bit deeper. So unfortunately, I didn’t find any conclusive results as to what is contributing to the current weather November has received. All I can say for sure is these things happen from time to time. And instead of worrying about it, think of a few of the positives if you live in New England: lower heating costs, cities are saving on snow removal, you can go outside and play like it is still early fall, and it is allowing people to say they climbed the mountain in November (a typical winter month; just don’t tell people about the nice weather you had). So enjoy it while it lasts because history has shown that winter will inevitably arrive regardless of what happens in November.

Observer Footnote: The attached picture was courtesy of our fall intern Will Tourtellet. It was taken tonight with a long exposure looking southeast. The lights you see are Conway, NH (closest), Lewiston/Auburn, ME (distant left of the picture) and Portland, ME (distant right of the picture). If you would like to see some more of his pictures, you can click here.

Ryan Knapp,  Staff Meteorologist