First Alert Weather


Daylight Saving Time: What Does This Mean?

Posted at 5:13 PM, Mar 08, 2015
and last updated 2015-03-08 17:13:00-04

(WTXL/USNO) -- While Daylight Saving Time occurring when it does is due to acts passed by Congress, there are some weather implications that are affected by this annual change, but a notable one for meteorology is the stall of weather models.

Global models finish runs an hour later than during Standard Time. Models such as ECMWF (European Center for Medium-Range Forecasts) and the GFS (Global Forecasting System) now start their runs an hour later due to the time shift and obviously end an hour later. The same with the NAM (North American Model) and CMC (Canadian) models. 

Coordinated Universal Time (UTC) is what all of these global models run on, which is why even though some areas don't observe the time change, the models still do, all across the planet.

This trend will push back the models runs an hour earlier during the Fall months when Standard time occurs once again.