National Weather Service revamps winter storm warnings

Experimental forecasts will acknowledge varying threat levels at different elevations


Graphics issued with winter storm warnings will change to make it more clear that elevation is a factor in winter storm conditions. Graphic courtesy NWS.

By Summit Voice

FRISCO — Planet Earth may be warming steadily, but a few pockets — including right here in Colorado — have been experiencing some chilly temperatures recently.

That includes Grand Junction, Colorado, where forecasters say December 2013 is headed for an all-time record low average temperature. Through Dec. 12, the West Slope town has averaged just 12.8 degrees Fahrenheit, 1 degree colder than the previous record set in 1978.

But don’t let the local cool temps fool you — NASA data released Dec. 13 shows that, globally,  November 2013 was the hottest since 1880, pretty much when accurate record-keeping started. All three record-warm Novembers have come within the past four years, putting to rest the global warming denier myth that there’s a pause in global warming.

The early December cold snap came courtesy of an Arctic air mass that spilled into the Great Basin and the Colorado Plateau, bringing snow and subsequent temperature inversions, with a layer of very chilly air hugging the ground, trapped by a layer of warmer air above. Long nights this time of year enable plenty of radiational cooling.

Grand Junction is also on track for one of its coldest years on record. According to the National Weather Service, there’s definite potential to break the record for the coldest average annual temperature — 49.9 degrees, set back in 1912.

Starting Dec. 16, the Grand Junction National Weather Service office is also revamping the way it describes winter storm hazards, with elevation-based warnings. The new experimental forecasts, set to start Dec. 16, will use elevation-based warnings to help people better understand the expected threat from a particular weather event.

The elevation-based warning will also apply to long-duration events, including winter storm warnings, high wind warnings and red flag fire danger warnings, but not for short-term threats like flash flood or tornado warnings.

An example of an elevation-based warning would be a winter storm warning only for elevations above the 9000 foot level within a particular mountain forecast zone.
Although the Grand Junction-area forecast zone includes elevations ranging from 7000 feet to 14,000 feet above sea level, the goal is to make it more obvious that the warning only applies to elevations above the 9000 foot level.
About these ads

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


Get every new post delivered to your Inbox.

Join 6,965 other followers

%d bloggers like this: