Monthly Archives: November 2012

Post-Sandy weather review

I started this post the day after Hurricane Sandy brushed past, but had forgotten about it. Perhaps it will be of interest even though it’s a bit out of date.

Here are a few pieces of information I had my hands on over the past couple of days as Sandy went by. I have a weather station and had my eyes glued to it as the storm came through.

Some weather station plots for the days prior to and just after the storm:

KMDBALTI22 weather station graphs 30 Oct 12

You can see very clearly when the storm came through by the various plots – deep “valley” in barometric pressure (new record low for my station – 961.59mB) and a peak in rain rate and wind speed. Curiously, there wasn’t a wind speed record set – it may be that we were on the “good” side of the storm, or it may be that my anemometer was malfunctioning – I replaced it a few days later.

I use Lightsoft Weather Center (LWC) software; unfortunately the developer got very ill and no longer supports the software. It still works fairly well, but I may need to replace it as it ages.

GRIB weather data (as presented on MacENC)

I don’t know much about GRIBs, and my area of interest in weather data is usually much smaller  than their resolution provides, but with the size of Sandy it really shows a good overview of the forecast conditions.

And below is some history for comparison: a few scans of old weatherfax sheets from a ship I was aboard in the mid-1990s in Alaskan waters. We frequently had strong non-tropical storms. Sandy’s lowest pressure was 943 mB; the lowest I recorded during Sandy was 961.59 mB.

Here’s a wicked looking 964 mB low from October 1995 (I think – may have been 1994?)

And here’s a 946 from December 1995(?)

This may have been the one where we holed up in Lost Harbor, Akun Island near Akutan Harbor and anchored in a sheltered bay where we saw sustained 80-knot winds. These storms are very different than hurricanes – “cold core” vs “warm core” and tend to come through in “trains” across the North Pacific.

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A visit to the Ballard Locks

When I was in Seattle a couple of weeks ago (but not for this) I had the opportunity to visit the Ballard Locks again. This year was special, as they had the main chamber dewatered. After visiting the beautiful Administration building and the control tower, I was able to climb down into the main lock chamber and check it out.  Here are a few photos from the visit:

Ballard Locks Admin Building

The foyer of the Administration building. Looks good now; it was even nicer last year when it was decorated for the holidays.

The dewatered main chamber as seen from the control tower. The gulls are enjoying dining on all the exposed sea life.

Dewatered saltwater barrier

The east end of the main chamber has a saltwater barrier on the floor; it’s buoyant and normally angled up (you can see the scrape marks on the far wall) and acts to keep heavier saltwater out of Lake Union and Lake Washington.

Empty chamber

View of the empty chamber from the chamber floor. Note the filling ports ont he left and right – there is a man-sized entrance just out of sight to the right that we went through and saw the filling tunnel. There is a cable on the floor in the center of the chamber; apparently that was lost or discarded by a tug and tow sometime since the last dewatering.

Filling tunnelFilling port

A couple of views from inside the filling tunnel – hard to see anything, as it was dark in the tunnel (duh) and the flash didn’t help. The first image is looking at the end of the tunnel where the water comes in from the upstream side; the lower one is one of the filling ports from the inside – this is the man-sized port that we walked through to get from the chamber into the tunnel.

Lots of aquatic life was exposed in the dewatered lock. Pretty much all underwater surfaces were covered with barnacles; sometime several inches deep. Part of the maintenance is to scrape them off – very laborious work. There were a lot of fish and crabs – you can see a crab pot that was lost in the chamber in one of the photos; perhaps you can make out some of the fish including flounder that blend in very well with the bottom.

A view of the locks from the south side. The lock grounds are almost entirely open to the public and are very well-maintained. The locks and fish ladder (just out of view to the right in this photo) are the second most popular tourist site in Seattle (after the Space Needle). I definitely recommend a visit!

Thanks to the guys at the locks (and I hope you get your LOMA unit installed soon!)