Winter Outlook and a Change in NWS Products
By Aaron Treadway, National Weather Service Austin/San Antonio
Winter Outlook/La Niña Update
As of late 2017 the Climate Prediction Center is forecasting a 55 to 65 percent chance of La Niña developing through the fall and winter of 2017-2018. La Niña is distinguished by unusually cold ocean temperatures in the Equatorial Pacific off the coast of South America (El Niño is the opposite, with unusually warm temperatures in the Equatorial Pacific). La Niña can change the overall weather pattern across the Northern Hemisphere, thus impacting the weather across the United States. In the U.S. La Niña creates a colder and wetter pattern in the Northwest, wetter in the Great Lakes region, and warmer and drier across the Southern half of the country. These trends are reflected in the Winter Outlook produced by the Climate Prediction Center (below).
For Texas this means that there is a 40% chance of a drier than normal year and a 50% chance of a warmer than normal year. The seasonal drought outlook, released along with the winter outlook, shows the potential for drought to persist across the ArkLaTex region and develop in the Big Bend and Rio Grande Valley regions of Texas through the end of January 2018.
For more information on La Niña check out past TEMO articles and the Climate Prediction Center:
For more information on the NOAA Winter Outlook:
Change to NWS Winter Products
Recently the National Weather Service has been working on a project to simplify the 127 different watch/warning/advisory products that we produce. Through surveys released to the public, emergency managers, and the media, in addition to working with social scientists, the NWS has not only changed the content of some products, but is also starting to combine products to make for a more straight forward and refined message.
Products like the Winter Storm Watch and Winter Weather Advisory will absorb some of the more specific products like Blizzard Watches and Freezing Rain Advisories and go into more detail about those events. While not overly common, the state has seen Blizzard Watches issued in 2011 and 2014 for areas of the Panhandle. Over the last 10 years much of the state has seen a Freezing Rain Advisory, with the most recent issuances being in the Panhandle and north Texas in 2017. If there Is a need for these products to be issued during the 2017-2018 winter they will now be within the Winter Storm Watch or Winter Weather Advisory. Check out the image below for more detail on the product consolidation.
In addition to the product consolidation there have been changes to the products themselves. Similar to the changes Severe Thunderstorms and Tornado Warnings went through with impact based warnings, the winter products now have a bulleted format to easily find information within the product. WHAT, WHERE, and WHEN bullets now tell stakeholders what the threat is (Ice? Sleet? Snow?), where the impacts will be greatest, and when they are expected. The consolidation of products and the reformatting benefit forecasters who now issue and update one single product rather than issuing, updating, canceling, and then reissuing different products for the different winter hazards. The simplification also helps users like emergency managers, the media, and the public by communicating all of the threats in one product that will be a consistent product rather than having to follow and interpret different products for different hazards.
Simplifying the winter products is only the first step in this process. The next step will be simplifying the flooding products issued by the National Weather Service. Check out the National Weather Service hazard simplification project for more information or contact your local Warning Coordination Meteorologist.