Winter or summer, the language the National Weather Service uses in their posts, broadcasts on weather radio, and other products is consistent and well defined. Looking for certain words can be a big clue as to how urgent the message is and how likely they think it will happen.
Of course, they have definitions for the main events they alert us to, things like thunderstorms, winter storms, floods, wind, blizzards, and once in a while even tornadoes. But most of us know all too well what those words mean without looking them up. From now on, I’ll just call those things the “event.” It’s the other words in the messages from NWS that need some clarification from time to time.
If they say there’s a “slight chance” of the event, that means 20% or less, 1 in 5. Between that and a 50/50 chance, they will use the word “chance” without the word “slight.” When they talk about chances above 50%, they say the event is “likely,” but when it gets more than 70% likely, they will just say the event without a qualifier. “Tomorrow: Snow,” for example.
If the event presents a hazard, the type of alert they issue tells you how urgent the alert is. A “Special Weather Statement” can be pinpointed to a small area and may include events that are only locally significant. Moving up on the urgency scale, an “advisory” tells of an event with wider scope and significance than a Special Weather Statement. When a “watch” is issued, that is more urgent than an advisory and means that a significant event might happen; time to make a plan in case it does. Finally, a ‘warning” is issued when a hazardous event is imminent or is actually happening, the most urgent alert of them all.
In NWS language, “isolated” events are fewer and farther between than “scattered” ones, and “patches” are not as big as “areas.” “Widespread” events cover more territory than patches or areas. “Severe” storms are worse than “strong” ones, and “heavy” snow or rain is heavier than “moderate,” and they are both heavier than “light” snow or rain.
As for the Teton Valley Weather Page, keep your eye out for words like “batten down the hatches,” “Katie bar the door,” or “grab the Cheetos.” You’ll know something’s up.