Snowfall in Philadelphia

Today, 9 February, it finally snowed significantly here in Philadelphia. In Chicago it probably snowed shortly after I moved out in September. Today’s graphic is a forecast map from philly.com using National Weather Service (NWS) data.

Snowfall in Philadelphia
Snowfall in Philadelphia

I fail to understand the divergent palette—to be fair this is not the only instance of it throughout the meteorological world. There is a split at the six-inch mark—but why? If anything, my eye would think that the 4–6 range is the heaviest, not the yellow. Snowfall is usually more of a continuous range, and so both within the blues and yellows you get that through a softer edge as the colours become more intense. And then you hit the six-inch mark and a violent shift.

I am also curious as to why the choice to use a coloured map background. Especially if the colour, a lightish green-blue is so close to the lightish blue used by the map to forecast snowfall.

In short, I think this Philadelphia map could use some attention from some designers to make the message a bit clearer.

Credit for the piece goes to the philly.com graphics department.

The Polar Vortex…Or Not

If you live in the United States, you probably have heard the term polar vortex by now. People have been using the term to describe the bitterly cold temperatures affecting the eastern two-thirds of the country. But the term polar vortex is a meteorological term that means a specific phenomenon. In other words, it’s more than a hashtag along the lines of snowmageddon. The Washington Post explains what the polar vortex is.

The Post explains the polar vortex
The Post explains the polar vortex

My caveat for this piece is that from my understanding, it’s not entirely correct. Or perhaps not detailed enough. In brief, we turn to the National Weather Service out of New York for a more technically correct, but more poorly designed graphic.

National Weather Service explanation
National Weather Service explanation

Poor type, poor colours, poor hierarchy. Those are abundantly clear, but the important part is that the NWS wants to correct many of the popular misconceptions. Somewhere between the well-intended but less-than-entirely-clear Post piece and the accurate-but-also-unclear National Weather Service piece is an opportunity to explain the concept to the public.

Credit for the Washington Post piece goes to Bonnie Berkowitz, Richard Johnson, Katie Park, and Gene Thorp.

Credit for the National Weather Service goes to the graphics team at the National Weather Service of New York.