The 2 most misused & misunderstood weather terms.

I like many yesterday was watching in awe at the 4-6” of snow on the field during the Detroit Lions versus Philadelphia Eagles game. That was some of the deepest snow I have ever seen during a pro or college game. Making matters worse it was a natural turf field which meant plowing it or sweeping is was not almost possible.

Screen Grab from ESPN.com about the mistaken “Blizzard”

As I watched I heard the announcers refer to the “Blizzard” occurring and cringed as a meteorologist. They weren’t alone most of my Twitter feed was full of references to the “Blizzard” during the game. One small problem it wasn’t even remotely close to a Blizzard and a Blizzard actually has nothing really to do with the amount of snow falling.

The Term Blizzard is actually about the wind not anything to really do with heavy snow.

Blizzard: (NOAA Definition):

Blizzards are dangerous winter storms that are a combination of blowing snow and wind resulting in very low visibilities. While heavy snowfalls and severe cold often accompany blizzards, they are not required. Sometimes strong winds pick up snow that has already fallen, creating a ground blizzard.

Officially, the National Weather Service defines a blizzard as a storm which contains large amounts of snow OR blowing snow, with winds in excess of 35 mph and visibilities of less than 1/4 mile for an extended period of time (at least 3 hours). When these conditions are expected, the National Weather Service will issue a “Blizzard Warning”. When these conditions are not expected to occur simultaneously, but one or two of these conditions are expected, a “Winter Storm Warning” or “Heavy Snow Warning” may be issued.

Blizzard conditions often develop on the northwest side of an intense storm system. The difference between the lower pressure in the storm and the higher pressure to the west creates a tight pressure gradient, or difference in pressure between two locations, which in turn results in very strong winds. These strong winds pick up available snow from the ground, or blow any snow which is falling, creating very low visibilities and the potential for significant drifting of snow.

You can have very light snow or just snow on the ground blowing around to get a Blizzard warning but you need very heavy snow falling for a Winter Storm Warning.

It’s not the only term that is misused and confused. The other is “Monsoon”. So many people think heavy rain is a Monsoon. It actually has nothing to do with describing rain falling. It’s really about a shift in the wind that happens on a seasonal level.

(via NOAA Arizona )What is the monsoon?

First, what is meant by the term monsoon?

The word “monsoon” is derived from the Arabic word “mausim” which means season. Ancient traders sailing in the Indian Ocean and adjoining Arabian Sea used it to describe a system of alternating winds which blow persistently from the northeast during the northern winter and from the opposite direction, the southwest, during the northern summer. Thus, the term monsoon actually refers solely to a seasonal wind shift, and not to precipitation.

Even though the term monsoon was originally defined for the Indian subcontinent, monsoon circulations exist in other locations of the world as well, such as in Europe, Africa, and the west coasts of Chile and the United States. Arizona happens to be located in the area of the United States that experiences a monsoonal circulation. During the summer months, winds shift from a west or northwest direction to a south or southeasterly direction. This allows moisture from the Gulf of California and the Gulf of Mexico to stream into the state. This shift in the winds, or monsoonal circulation, produces a radical change in moisture conditions statewide.

This monsoonal circulation is typically referred to here in Arizona as the Arizona monsoon. What we experience during the summer months, however, is only a small part of a much larger circulation that encompasses not only Arizona, but much of the southwestern United States and northwestern Mexico. Thus, it sometimes is also known as the Mexican monsoon. Others call it the North American Monsoon.

In both cases people misused a term to describe heavy snow or rain when it really is all about the wind. File this one away in “The More You Know” folder.