Cold Air Update

The Arctic air coming next week is taking over the weather headlines. As James discusses below, the timing of the cold air, also how cold it will be and whether there will be any ice or snow, is very difficult to forecast now. We are talking about air that has to move 4,000 miles or so, and pinning that down is tough. The models have trouble with shallow cold air like this, so they could be underestimating how cold it will get here, but we don’t know yet.

We are confident that very cold air is on the way next week. It has built to the point now in Alaska and NW Canada that its weight will force it to spread out. All it needs is a low pressure area to form up there and help pull it south. Here is a map I put together of noon CST temperatures…I had to put together several map pieces to get more observations and detail, so it’s not one you’d hang on the wall. It’s also a very large png image, so I’ll put it here in small size…but you will probably have to click on it to make it bigger and see the numbers.

Notice how many stations over a wide area are below -30. There are plenty of -40s and -50s, too. These are temperatures, not wind chill factors. The -58 at Dawson City, Canada is the coldest one I see. Also, it reached -68 yesterday at Chicken, Alaska.

This whole thing has actually been developing since Summer. They never really had a summer in Alaska, had an early snow cover, and temperatures were already below normal in the fall. JB Elliott and I discussed this over Chinese doughnuts one day in September…I predicted this could be the year BHM went below zero, and JB predicted we could have a 6″ snow. Brian Peters also threw in the large webs spiders were building, maybe in preparation for a cold winter. One minute of audio clips from weatherbrains on October 6, 2008 are attached below. Just click to listen.

coldairdiscussion

This will be a fascinating situation to watch. Again, the timing is difficult. Just prepare for a the coldest temperatures in years late next week, and possibly staying below freezing continuously for 48 hours or more. This is the kind of cold that could burst pipes, etc. For what it’s worth, my prediction for BHM’s lowest temperature next week is 8.

Category: Uncategorized