In my previous article about the National Weather Service’s Forecast Discussions I touched briefly on another set of products the NWS releases: outlooks, advisories, watches and warnings. These alerts are designed to help those planning on being out in the elements prepare for forecasted severe weather. Outdoor photographers can use these alerts to determine the best times and places to capture dramatic weather conditions, and learn when they should seek shelter from dangerous weather. Understanding the differences between the four types of alerts and how to decipher them is one more tool weather-savvy photographers can use to get epic weather shots.
I Advise You to Watch out for Warnings
As weather disturbances develop that may effect a region, the NWS office for that area will issue a series of alerts with information about the threat of severe weather. The first product issued is an Outlook. In an outlook the forecasters will give broad detail of the potential severity of the developing weather days ahead of the possible event. Think of outlooks as the heads-up that some serious weather may be on the way in a few days. Once confidence has grown beyond 30% that the weather will in fact be severe and follow a predictable path and timeline, the forecasters will issue a watch, warning or advisory. If the weather event carries the potential for damage to property or risk to public health, and the forecasters are at least 50% confident of the event’s severity, they will issue a Watch. Watches tend to be issued about 48 hours in advance of the arrival of the event. When the confidence in an event reaches 80% and the event poses a risk to life and property the weather service will issue a Warning. If the severity of the event is not sufficient to risk life or property, but it is sure to be a nuisance, the service will issue an Advisory. For a more detailed description of the myriad of various outlooks, watches, advisories and warnings the NWS produces, check out this page.
To Go or Not to Go, That is the Question.
When the weather service forecasters issue a watch, warning or advisory, they will disseminate the news via their website and local news providers. In some areas you can pick up weather radio broadcasts that will detail the alerts, and you may even have the option of signing up for text and email alerts that are sent to your smart phone by local emergency management agencies. Check with your local emergency management agency to see what sort of weather alert options they have.
In my last article I shared an image of the Portland, Oregon National Weather Service office web page that showed all of the active alerts in my region. Today the weather is pretty quiet here in Oregon, so I looked to the north where a very wet weather system is bearing down on Washington State. Here is Seattle’s NWS page for today:
As you can see, there are a few marine watches, warnings and advisories for the coastal waters off of Washington State (shown in shades of pink and purple), while inland warnings, advisories and watches show up as green. A Hazardous Weather Outlook alert is also shown in light yellow. On the web page, you can click on any of the colored areas of the map for a textual description of the active alert, or you can select the tab in the upper left corner of the page to show a listing of all active alerts for the region. Here is what that page looks like:
Things are looking pretty wet for my friends in the Evergreen State over the next few days. There are numerous flood watches, warnings and advisories up for the area and as usual with these types of winter storms, the coastal and inland waters are going to be whipped up by the wind and seas will be running high. Not a great time to be a boater, but pretty awesome stuff for photographers who don’t mind getting rained on to get dramatic wave shots.
Makes Sense of the Alerts
If you are looking for rough weather photos, it makes sense to look at the warnings first. They are the sure bets for severe weather. In our example above, you can see that there is a flood warning active for Mason County on the Olympic Peninsula. By clicking on the warning link, I was able to open the fully detailed flood warning:
Unlike the Forecast Discussion produced by the NWS forecasters, alerts tend to be in plain language that leaves little room for misunderstanding. At the top of the warning is the forecast office identifier, date and time of the alert, and a short description of the scope of the warning. Further down the forecasters provide details about the risk to life and property and their forecasts for the event in question. Because they are in the business of keeping people out of trouble, they include directions for avoiding danger. Below the four lines of codes is a summary of warning information. I find this list to be the meat of the alert with very detailed information about what can be expected during the event. In this case, the Skokomish River near the little town of Potlatch is going to flood, but not severely. It will crest one foot above flood stage Thursday afternoon and recede back below flood stage by Saturday morning. I know from the warning that this type of flooding will only effect farmland and two roads. As a weather-chasing photographer I now have great information that can guide me as I head out to photograph the flood.
Safety First, Second and Last.
It bears repeating that photographing severe weather is dangerous. The conditions that make for dramatic photographs also make for risky driving and walking outside. Storm photography is exciting and the images you can get during severe weather events are compelling, but only if you survive the storm to share them. I’ve lived and photographed severe weather in the Pacific Northwest for 30 years and I have seen other photographers take foolish risks to get the shot. For more on my thoughts about risky outdoor photography, please read my blog post “Risk Appetite“. Please be a safe and weather-savvy photographer!