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HOUGHTON - Even the National Weather Service can't do it alone.

So meteorologists gave a presentation at the Houghton County building Wednesday night to discuss winter weather conditions found in the Upper Peninsula, as well as the importance of community involvement in weather monitoring.

Most lake effect snow takes place less than 10,000 feet above ground, making it difficult to track on radar, said meteorologist Matt Zika. Because of that, he said it's vital to have community spotters feeding the NWS information about developing weather.

Typically, Zika said, observers measure highs, lows, amount of snow and rain.

"It's our only way to truly measure how the climate is changing across the country," he said.

And it's useful to have that measure take place in the same spot; moving even 2 miles down the road invalidates the comparison, Zika said.

Zika distinguished between snowfall (the amount that has fallen since the last measurement, measured to the nearest tenth of an inch) and snow depth (total accumulation of snow since the season began, measured in inches).

New snowfall is ideally measured at a point near its maximum accumulation.

"If it melts, and you've got a trace amount, then officially you've got a trace amount," he said.

New snowfall is measured on a snowboard, ideally placed in a small clearing; alternatives can include a picnic table, or a pavement if it's cold enough.

"You want to get a surface that's cold enough for snow to accumulate, in a wide-open area," Zika said.

Snow depth is measured at multiple locations throughout the yard and then averaged; wind-blown areas are to be avoided, Zika said.

The goal is to have two measurements per day at 7 a.m. and 7 p.m., Zika said; if that can't be done, then the time frame of the report is still important.

In the case of fast-breaking winter storms, Zika said to notify the NWS, which may not know about highly localized conditions.

"The more information we get from you, the better off we are," he said.

Zika discussed what goes into declaring winter weather advisories. A winter storm watch indicates a "pretty high probability of a major weather event" within 72 hours, while a winter storm warning indicates "hazardous weather is likely within the next day."

For blizzard warnings, he said, the driving factor is not total amount of snow, but visibility.

"People think that's the worst, and it usually is, but it has nothing to do with snow," he said.

Moisture plays a part. Six inches of wet snow, which can weigh down power lines, may trigger an advisory; for drier snow, it may take 12 to 15 inches.

The U.P. is the only place Zika's seen where advisories don't trigger a run on stores, he said, comparing it to Alabama.

"Down there, you mention a flurry in a forecast, you can't buy milk or bread for three days," he said.

Because of the potential for frostbite and hypothermia, the NWS reports the most extreme wind chill in an area. But measurements such as wind chill and snowfall can vary dramatically over the span of even a few miles.

Last year, he said, several thin bands near Lake Superior, including most of the Keweenaw Peninsula, received above-average snowfall.

"You get away from there, and most of the interior regions were at the average snowfalls," he said.

Due to El Nino, this year's winter has only a 30 percent chance of being colder than normal, Zika said.

But, he said, "it's still going to be cold. It's still going to snow."

The region has seen increased snowfall over the past few decades; five of the last 11 years have been the snowiest on record. However, Zika said that could be the result of improved measuring. In the past, snowfall was measured by melting the snow and assuming a 10:1 ratio (10 inches of snow makes one inch of water). While this works for many parts of the Midwest, it undercounts dry, fluffy lake effect snow, where a normal measure could be 30 to 50 inches of snow. The colder the temperature, the less liquid there is.

The 100-year temperature trend in Michigan is almost flat, Zika said. But there's been a definite trend toward warmer falls, and a slight downward trend in spring temperatures.

The average growing season at the NWS station in Marquette has also gotten longer, going from about 95 days in 1962 to 130 days in 2008.

Seasonal snowfall totals have increased somewhat at Marquette, while staying flat at Iron Mountain.

Meteorologist John Voss talked about seasonal low-pressure systems, including "Alberta clippers," large systems of cold air that push down through the Great Plains states.

Voss discussed lake effect snow bands, the place where warm air ascends from the lakes. In between those bands, cold air descends. The U.P. most commonly sees multiple bands, which are parallel to the average wind direction within the cloud layer.

With drier air, Voss said, there's wider space between bands, and less snow; for wetter air, there's more intense snow, and less space between bands.

"If you get a real cold air mass coming from Canada, and it's wet ... you've got a pretty good shot at seeing heavy lake effect snow," Voss said.

One strong band developed over the Keweenaw on Feb. 2 of last year, Zika said, depositing two feet of snow in a matter of hours.

In areas between bands, there can be much less snow. Topography also makes a difference; someplace 100 feet higher can see eight to 12 more inches.

Extreme cold can also cut down on snow by limiting moisture and keeping snowflakes small.

Aside from some sluggish parts in the middle, Pete Method of Hancock thought it was "overall, a pretty good presentation."

Method went to a program in Eagle River in the spring to learn about reporting storms in the summer.

"There wasn't anything to report on over the summer, but I expect there'll be a lot to report over the winter," he said.

Garrett Neese can be reached at gneese@mininggazette.com.