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After a particularly nasty winter, Alaskans usually hope for a nice summer to erase the memories. Actually, a lot of Alaskan’s do that after every winter.  Well, we are just finishing up (or still waiting for the end of, depending on what part of Alaska you live in)  a very tough winter in most parts of Alaska, so hope runs high for the summer. Will it soothe or disappoint the weather weary?

The truthful answer? I don’t know. Seasonal forecasts for the warm season have little skill in Alaska. Worse than winter forecasts, which are far from reliable.

There are two points pertinent to this issue:

1. Temperatures vary much less in summer than in winter. While that might make it easier by reducing the potential forecast error,  in reality the forecast needs to show skill within the context of that variability. This is the technical explanation. From a human standpoint these smaller temperature variations seem to be relatively more important in summer, perhaps because there is more outside activity. There is about as much grumbling about a 3 degree colder than normal summer month as there is about a 6 degree colder than normal winter month.
2. Correlations of summer weather in Alaska with climate systems such as the El Nino/La Nina are either too weak or as yet too poorly understood to be a very useful predictor of a particular summer. Frankly most people have been trying to figure the links with winter weather, probably because winter weather is seen as more important (dangerous, costly, etc.) and I suppose that is right to an extent.

So I’m not putting much confidence in my prediction, and asking you not to as well. This is more of a theory to be played out over the next 3 months than something to make decisions on. Read the rest of this entry »

Memorial day is used in many areas as a marker for the start of summer. Not in St. Paul, Alaska. Today they observed the holiday along with rain, freezing rain, temperatures hovering around the freezing point, and sustained winds around 25 mph, bringing wind chills down to the teens (in F, or around -12 C) . This is one of the more extreme examples of the extreme winter that does not want to leave.  I usually do not include May in a winter summary, but this year it seems to want to be in there.

How bad was the winter? In a nutshell, most of Alaska had much more snow than usual, the exception being the interior, where snowfall was not far from average. Here’s the final standing in the Iditasnow, the friendly inter-community snow rivalry. (click for larger version)

total snowfall for 2011-2012 season

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If you have been waiting to see some statistics on how our winter of 2011-2012 rated compared to climate history, or if you were hoping for a long range forecast (educated guess) for the summer of 2012, stay tuned, I am working on both. I’ve been preoccupied with getting the 2013 Alaska Weather Calendar printed and out to stores. That rush is easing and I hope to increase the blogging frequency at least to where it was before. If you would like an automatic email when a new article is posted, sign up for that service under “Subscribe to Posts” either on the menu items across the top of the page or on the right hand sidebar items.

Of course, I can’t really do a winter wrap-up or declare a winner in the Iditasnow until winter is a little more over, can I? Look at what has been happening around the state:

In the Arctic, no one expects anything like spring weather for some time to come. In fact, the weather there has been pretty average for this time of year: Temperatures in the 20s F (around -5C) with some wind, a little snow and blowing snow lately. However, just a few days ago it was below zero on the North Slope and Bering Strait area. After a very snowy winter in Kotzebue, the 27 inches (69 cm) of snow on the ground is holding steady with well below freezing temperatures.

The plows are still needed in Shishmaref. Click on the image to see it full size.

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Since the leap day checkpoint report, most towns have slowed their snowfall pace. Haines and Yakutat, however, have been running hard, each having added an impressive 50 inches this first half of March.

The Top Ten as of 15 March

Remember, the standings are based on snowfall this season compared to the station’s average yearly snowfall. (No, I did not come up with this rating scheme to just to put Haines in the lead). Read the rest of this entry »

Today is the start of the world famous Iditarod trail sled dog race (“the last great race”), so I thought maybe I should give an report on another (unofficial) great race: the Alaska snow race. It has been a very snowy winter in many parts of Alaska and there is plenty of talk and a little bragging and comparing between towns, so why not make a little fun of it? In no way am I wanting to make light of the real hardships experienced in places like Cordova and Valdez, where schools were closed for more than an isolated “snow day” due to fears of structural failure of school buildings, among other problems. Believe me, I understand the issue of dealing with tons of snow, since I live in one of the major league snow towns (Haines). What I want to do is compare details of a longer list of places facing heavy snow this winter, and look at why. First the standings, as of the leap day checkpoint: units are inches for snow and feet for elevation.

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The huge section of heavy old snow pictured below finally slid off the roof of our shed sometime in the middle of the night recently. Luckily, it remained jammed vertically in the snow below and did not fall against the shed. What do think it weighs? Click on the photos for a better look…it’s the same berg from opposite ends.

It would not be hard to estimate the weight of this thing if we knew its density. And you might want to know the density your snow for a variety of reasons. One of the more common reasons is to figure if the weight of the snow might damage something. Check out the scene from our school a couple weeks ago: Read the rest of this entry »

It’s been a cold winter across most of Alaska. It’s not the first and it won’t be the last. During every winter there are relatively colder and warmer periods. This year these cold snaps and warm spells seem to be aligned pretty well to the calendar months: November was cold, December warm, and January…one of the coldest, especially for the rail belt and everywhere west. Check out the write-ups from Weather Service personnel in Anchorage http://pafc.arh.noaa.gov/papers/THE%20COLD%20FACTS.pdf and Fairbanks https://nwschat.weather.gov/p.php?pid=201202012052-PAFG-NOAK49-PNSAFG. February is staring off with a big warm-up, thanks to a strong low barreling into Alaska’s midsection like a gut punch. I’m not making any promise that this trend will hold for February. It does look like a week to 10 days’ break for from the cold, but beyond that, I’d be surprised if we don’t get a fair amount of more cold weather (and snow for the coastal and near coastal areas) before the winter is over. See the Climate Prediction Center for more. For this post, however, I want to zero in on an interesting pattern that seems evident during the worst of the cold snaps. Let’s start with this map, used by permission of the Anchorage Daily News.

The figures show the coldest temperature (degrees F) endured at each city over this past weekend (28-29 Jan). Read the rest of this entry »

Alaska is a big place, and the weather system affecting our state right now is even bigger, but I’m going to show you that is it the small scale that counts when it comes to winds of the south and southeast coasts. As I write this, virtually the whole state is under the influence of the strong pressure gradient between a large, deep low in the Northeast Pacific and strong but gradually weakening high pressure in Siberia and the Alaska interior. (The high was up to a crushing 1060 mb a few days ago, compared to the still hefty 1040 mb on this map) Here is the surface map from 3 pm/00z this afternoon from the GFS model (It’s the 12 hr forecast which is about as good as an analysis):

You probably know that where the isobars are drawn with the closest spacing is where the gradient is the strongest and therefore where the wind is supposed to be the strongest. Read the rest of this entry »