KALISPELL (AP) -- The collision of two powerful winter storm systems over Glacier National Park has produced gale-force winds and extreme temperature fluctuations in recent days.

''It's like watching two sumo wrestlers," said Blase Reardon, with the U.S. Geological Survey.

''We've got two really big, powerful storm systems, with cold, heavy air east of the pass and warm, wet air to the west. One gives an inch, the other takes an inch."

Reardon, an avalanche specialist with USGS, installed the weather sensors on the Logan Pass visitor center that have reported the impressive readings.

In the past week the sensors have recorded steady gale-force winds, with gusts of up to 102 mph, and temperature swings of more than 50 degrees within a few hours.

The Pacific fronts prevailed for much of the week. Between noon Wednesday and 6 p.m. Thursday, the sensors showed winds with an average sustained speed of 43 mph -- a perfect gale, according to the Beaufort wind scale classification system.

Hourly wind readings ranged from a low of 28 mph to a high of 64, with gusts of 59 to 102 mph. On the Beaufort scale, 64 mph is a ''violent storm" one step below hurricane status -- something that is ''seldom experienced on land" and that can result in ''considerable structural damage."

The 102 mph wind gust on Wednesday was only the fifth-highest gust recorded at Logan Pass this winter, Reardon said.

''We hit 113 mph earlier this season," he said. ''In November and December, we had sustained winds averaging more than 80 mph. I can't believe the sensors are still up."

Reardon said the visitor center should be well protected under its covering of snow. The weather equipment is bolted to the chimney and reports data by radio.

Gene Petrescu, a meteorologist with the National Weather Service in Missoula, said when enough Arctic air pushes down from Canada, it spills over Logan Pass like water over the edge of a bathtub.

''That's when we'll see rapid wind shifts and sharp drops in temperature," he said.

For example, when the wind shifted to the east after 2 a.m. on Tuesday, temperatures at the pass dropped 33 degrees in an hour, from 16 above to 17 below. As the wind strengthened, temperatures fell another 19 degrees, to 36 below, by 7 a.m. The wind chill at that point was 73 degrees below zero.

The wind shifted back to the west in the afternoon, allowing temperatures to rise from 36 below to 20 above within eight hours.

''In Browning on Wednesday, temperatures dropped 44 degrees in one hour," Petrescu said. ''At Deep Creek near Marias Pass, the temperature went from 31 above at 10 p.m. to 17 below at 11 p.m., and back to 31 above by midnight."