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Revising Alert Policy

I normally don’t allow “Winter Weather Advisories” (WWA) to post on the City page (home page), because too often those end with unremarkable snow totals here. Also, people tune out after a certain point if they are constantly barraged with alerts, which can happen during the winter here.  When you see an alert posted on our main page, you can generally place confidence in its importance and relevance to the city.  Note that the detailed forecast will always specify accumulating precipitation within the next couple days regardless of alert status.

When I saw the Winter Weather Advisory hoisted on Friday (1/17/20), I decided to post it. I could see that just the front-end of the incoming storm was forecast to deliver 4-7″ in about 12 hours. I could also see that conditions were right for a decent amount of lake effect over the following 24 hours.  The $64,000 question, as always, was “how much?”

The weather models aren’t good at estimating the quantity of moisture the lake can generate. That’s why the automated weather apps often under-estimate or entirely miss significant lake-effect events. In the end, it’s up to forecasters to look at the fundamental dynamics — which are available using a blend of models, observations, and experience — to determine snowfall amounts.

I’m guessing it was a close call for the local National Weather Service (NWS) as to whether to post a WWA or Winter Storm Warning (WSW) for the county. In fact, the eastern portion of the U.P. was upgraded on Saturday to a WSW. There are minimum timeline thresholds that are part of each alert product. So simply receiving a certain amount is insufficient. It must fall within a particular window of time (12 or 24 hours).

In the end, however, I’m okay with how it played out. I’d rather the NWS reserve a Winter Storm Warning for when they are more confident.

But this brings me to the question of whether I should allow Winter Weather Advisories on the City page. I imagine that most Marquetters don’t stay exclusively within the city limits over the course of 36-48 hours, the length of a typical significant weather event. Although I worry that it’s confusing to have, oftentimes, much more impactful statements appear on the same page as a forecast that may not align with those statements.   On the other hand, people should have access to information concerning what they may encounter as they venture into the surrounding area.

Well, as of today, I’m going to allow Winter Weather Advisories to automatically post to the home page. I may strike them in certain instances (like if the city will receive mostly rain rather than snow). You can always see all (land-based) alerts for Marquette County on our Area page.**

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* Alerts posted on this site are intended to cover all of Marquette County. The local National Weather Service is, therefore, obliged to consider most areas within the county boundaries when deciding which, if any, alert product to issue. With most of the county being at least 500′ above us, average projected snow totals used to justify a given alert will generally be higher than what we receive.

** Also omitted from the main page are “Special Weather Statements”, as most of the time they do not apply to the city due to its lakeshore proximity and heat-island effects. For example, if you warn someone of fog 10 times, and they only experience it once or twice (due to diabatic heat sources raising the air temperature above the dew point), they start to doubt you. Much more importantly, they begin to doubt your ability to alert them to significant and/or dangerous weather.

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