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2014 Shareholder's Report National Weather Service 2014 Shareholder’s Report La Crosse, National Weather Service, La Crosse, WI Wisconsin web: http://weather.gov/lacrosse mobile web forecast access: email: [email protected] Find us on Facebook: mobile.weather.gov US National Weather Service La Crosse Wisconsin Weather Information Services that Mean Something or Twitter: By now, you may have heard weather element, good, timely @NWSLaCrosse the National Weather Service decisions can save lives. And (NWS) talking about “Decision sometimes, that may include you Support Services (DSS)” for or those close to you. weather. But you may not be NWS La Crosse sure what that means to you. When I was a young manager in the NWS, I was told by one of Management Team If you’re like most people, you my forecasters that “we don’t may get your weather infor- even know who uses our fore- Glenn Lussky Meteorologist in Charge (MIC) mation from the local radio or casts, or even if anyone does.” TV station, or perhaps you use While I knew some people used Todd Shea the NWS web site to access our forecasts (e.g., the media), Example of NWS La Crosse graphical Warning Coordination the very latest information. You that forecaster was largely right. Meteorologist (WCM) weather story. This type of information hear or look at the forecast We didn’t know many of our supplements our historically traditional Dan Baumgardt and consider how it may im- users or, even more importantly, routine forecasts. Science and Operations Officer pact any activities you, your what information they needed, (SOO) family, or your business may when they needed it, or whether you can, whether for your family, have during that time period. the information we were provid- your business, or for a specific event. Mike Struver Please check out and share our social Electronic Systems Analyst (ESA) ing met their information needs. The forecast can help, for sure. media posts, our web page news Randy Breeser But sometimes, people need That forecaster was 20 years stories, and our graphical short term Data Acquisition Program forecasts and recorded briefings. Manager (DAPM) more or different information ahead of his time. Today, it is to help them make good deci- our goal - no, our purpose - to They are there specifically for you! sions. With the help of NWS know what information people impact-based DSS information, want or need and provide it to I welcome your comments regarding how we can provide better weather Inside this Issue: communities and event manag- them in a clear and timely man- ers are more frequently making ner. That, is DSS, and it applies information for you - whenever, Cold Weather and 2 educated weather-related deci- to everyone we serve. wherever and however you need it! the Polar Vortex sions, with a goal of keeping their citizens or patrons safe. In this regard, we are making Social Media Expan- 2 sion at NWS La Whether the event includes every effort to provide not just a Glenn R. Lussky Crosse extreme cold, slippery roads, forecast, but impact-based infor- lightning, high winds, torna- mation that helps you make the Meteorologist in Charge (MIC) Web-based Storm 3 does, flooding, or any other best weather safety decisions NWS La Crosse, WI Summaries July 22nd “Refuge” 4 Decision Support Update Tornado—The Im- portance of Storm The NWS continues to ad- ules a webinar briefing to Spotters vance services which assist emergency management and partner groups in making criti- community preparedness AWIPS-2: Open 4 cal decisions during hazardous groups. Roughly 10 minutes Architecture to Add weather. This “Decision Sup- long, these live briefings via Future Flexibility port” work and development is the web include a slide set Awards, Recognition 5 a focus at the La Crosse NWS explaining the expected and Personnel office, and we’ve added new weather and potential impacts Changes and enhanced methods to planners can expect. In addi- share key information. tion, this interaction provides Forecasting an His- 6 Sample briefing slide from January 3, 2014 toric Late Spring an opportunity for those on Snow Event: May 2- Decision Support Webinars: the call to ask our meteorolo- 3, 2013 Preceding episodes of poten- gists about specific questions or Webinars have been used for a tially hazardous weather, the La concerns they may have. number of years, with attendance Crosse NWS typically sched- (continued on page 3) Page 2 2014 Shareholder’s Report Cold Weather and the Polar Vortex The winter of 2013-14 has been quite cold ester, this has been their coldest weather Any intrusion of very cold air over central across the eastern two-thirds of the United for this time period in the last 30 years. North America in winter is simply an ex- States. Through January. the greatest de- tension (or shifting) of the polar vortex partures from normal (9 to 14°F below While many had never heard of the polar into the region. This winter, the polar normal) were across Upper Michigan and vortex prior to this winter, meteorolo- vortex has shifted substantially over both the northern portions of Minnesota and gists have been well aware of this feature Siberia (Asia) and North America. Wisconsin. for a very long time (one literature search indicates it was first described in On several occasions this winter, cold air From December 1st through February 6th, the scientific literature in 1853). In fact, masses originating over Siberia (where the this has been the coldest winter at La the polar vortex is a centerpiece of the coldest land temperatures are usually Crosse, Wisconsin (11.7°F) and Rochester, global circulation pattern. It is always observed during the winter) have moved Minnesota (9.2°F) since 1983-84. there, in one form or another. over the North Pole into northern Cana- da. Under certain flow regimes, these The polar vortex is simply a low pressure very cold air masses can be transported area in the upper atmosphere centered southward into the central U.S. In sea- generally over the polar regions (both sons where these flow regimes dominate northern and southern hemispheres). (such as this winter), the result can be a The polar vortex is that ring of cold air very cold winter for the central U.S. that sits on the poleward side of the polar jet stream. The associated wind While this winter has been atypically cold system which surrounds the polar vortex over our area, this isn’t something that is is the westerly mid-latitude jet stream. due to a new scientific finding. It is simply a manifestation of one particular global By definition, the polar jet stream is lo- circulation pattern which has consistently cated on the periphery of the polar maintained a cold portion of the polar vortex. This jet stream demarks the vortex over our area this winter. equatorial extent of the cold arctic air. There are times when the polar vortex is centered near the pole, with most of the very cold air confined to the polar regions. However, there are other NP NP Locales to our north have had an even times when portions of the polar vor- more extreme winter. During the same tex push southward (often toward the period of time, Duluth, Minnesota had an Eurasian or North American land average temperature of 3.0°F. This is al- masses), leading to stronger southward most 10°F below their 1981-2010 normal, intrusions of cold air into those areas. and is the 3rd coldest on record (since At those times, the pole and other At left, the polar vortex keeps the cold air centered on the pole, with few intrusions of polar air into the 1875) for this time period. Only the win- mid-latitude regions typically have mid-latitudes. At right, the polar vortex has split ters of 1917-18 and 1976-77 were colder. warmer than normal conditions as and pushed southward over the main Northern The Twin Cities have averaged 9.8°F (6.7°F the cold air slides southward. Hemisphere land masses, and warmer than normal below normal). Like La Crosse and Roch- air is located over the North Pole (NP). Social Media Expansion at NWS La Crosse The past year has featured a significant saving information as we can. In that re- As of February 1, 2014, we had 4,244 Face- expansion of social media services that gard, social media can play a crucial role in book and 1,696 Twitter followers, with new the NWS La Crosse office provides via people finding our pages every day. A num- Facebook, Twitter and YouTube. “Through the power of information ber of followers post pictures and reports sharing, social media provides a great to our pages, which we share with others, Posts to Facebook and Twitter are typi- especially when inclement weather is occur- way for us to reach many more people cally made at least once each day to give ring. Twitter users can append our hashtag a general overview of the most im- than just those who closely follow the (#nwsarx) to their tweets to alert us of portant upcoming weather story. As traditional NWS information stream.” their information. We have also started to more significant weather events are use YouTube to post short briefings on forecast (or occur), our activity on these our entire DSS program, as they help upcoming weather events, along with educa- social media sites increases in an effort spread impact-based information people tional and outreach material. to communicate as much potentially life- need to make good, life-saving decisions.
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