Weather Blog

Potpourri blog: Mt. Rainier snow, sun dogs, and crazy weather

Potpourri blog: Mt. Rainier snow, sun dogs, and crazy weather

It's been such a busy spring that there have been some blog topics that got left by the wayside and got a little stale in doing so, but figured I'd give them their day in the sun here instead of relegating them to the recycle bin:

Oklahoma tornado big, Napavine tornado small

A few weeks ago, I wrote about the legendary weather station that survived a direct hit from a major tornado that went through El Reno, Oklahoma. It recorded wind gusts of 151 mph and an 11 milibar pressure drop in two minutes.

A short time later, the Northwest had our own tornado that touched down near Napavine on May 27. Turns out, there was a weather station fairly close to that one too. It was reporting light northeasterly winds in the minutes prior to the storm.

Then when the tornado hit, the wind shifted to the southwest at... 15 mph, but it gusted to 22 mph! As the tornado passed, the wind shifted back to due south and calmed right back down again. But interestingly enough, it did record a 1 milibar pressure drop in 10 minutes -- still quite strong by our standards. The tornado itself registered an EF0 -- the weakest rating -- with top wind speed of 75 mph, so just goes to show how much weaker the storms are here.

Chilly spring in Seattle means it's hot somewhere else

Does it seem like springs have been getting colder recently? You would be right. The past three of four springs have been below normal and this chart below, showing average temperature from March-May from 1986-2011, shows it pretty conclusively.

(Thanks to State climatologist Mark Albright for the chart)

But the planet usually works on the premise that if it's colder than normal somewhere, it's warmer than normal somewhere else.

In the U.S., that was the lower Midwest and the Southeast, where it was a very warm spring:

And Europe has had a blistering spring so far -- Meteo France (France's version of the National Weather Service) reports it's been about 4.5 degrees F above normal for March to May. It's also been their driest spring in 50 years.

Sun Dogs Galore

This spring has seen its share of sun halos, and there are a few more I've missed showcasing.

Here is an image taken by Richard Harris from West Seattle:

And this is a video taken from Dr. Dale Ireland's web camera in Silverdale:

Speaking of Dr. Dale, his other recent photograph of a sun halo made the Atmospheric Optics Photo of the Day. That site also has a fantastic explanation of how sun halos work.

And speaking of rainbows, check out this double rainbow with a few color echoes, taken by Joni Bentley. These "echoes" are called Supernumerary bows and according to the Atmospheric Optics site are caused by tiny raindrops.

More great optical sights

How about two sun tricks on the same evening? Jim Mihara captured these two sun events on the same evening (May 28) about an hour apart from Magnolia.

The first is one of the sun dogs like above; the second is of a sun pillar

Lots of snow on Mt. Rainier:

According to Albright, on June 1, the snow depth at Paradise Mt Rainier stood at 213 inches, the 2nd greatest June 1 depth in the 91 year historical record.

Contrast this with 6 years ago, when there was no snow remaining on June 1, 2005.

Spring was gloomy; winter only marginally better

And finally, I totally missed posting this info as a blog entry at the end of winter. David Obelcz calculates a rating for both winter and summer. His "Winter Misery Index" rated the winter of 2010-2011 as below normal, but not historically bad.

How does the index work? As Obelcz explains:

"The Winter Misery Index evaluates temperature, rainfall, snowfall, and accumulated snow from December 1 to March 31 from 1948 to 2011. A score is created based on the month, the day of the week, and the weather. The rarer, warm and dry winter days received a higher score, while days that were cold with accumulating snow got the lowest scores. The winters with the total lowest score were rated as the most miserable."

Coming soon in mid-June will be an update to the "Barbecue Index" which measures spring. That will post after the period ends on June 11.