State's average 2015 temp ties highest on record

Montana tied its highest average overall temperature in 2015, according to weather data.

Statewide, the average temperature last year was 44.9 degrees, which was 3.8 degrees above the 20th century average, according to year-end data released by the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information.

The 44.9 degrees tied the highest average temperature set in 1934, according to Jake Crouch, a climate scientist with the centers.

The high temperatures, combined with limited winter snowpack, contributed to summer drought and a severe wildfire season last year, Crouch said.

The National Weather Service’s weather station at Glacier Park International Airport registered an overall average temperature of 45.5 degrees in 2015, tying for fourth place in the agency’s record of data going back to 1899.

Kalispell’s hottest year was in 1925, when the average temperature was 45.8 degrees.

Southwestern Montana was particularly warm and dry in 2015, said Dave Bernhardt, a National Weather Service meteorologist in Great Falls.

Dillon averaged 46 degrees in 2015, the warmest on record for that city, according to the Weather Service.

The community’s previous warmest average temperature was 45.2 set in 2012. Dillon also had its second warmest winter on record.

Average temperatures for the year in Helena (48.2) and Bozeman (45) were the second-warmest on record.

“Along with that, there were a lot of record-high temperatures and a lot of those occurred during the winter and spring months in the southwest,” Bernhardt said.

Dillon had 22 record high temperatures during 2015 and Helena had 18, he said.

“To have that many record highs, that’s notable,” Bernhardt said.

Kalispell experienced its hottest June on record and several record high temperatures. That month, the mercury broke 90 degrees eight times — another record.

For both northcentral and southwestern Montana, it was the warmest summer on record since 2007, Bernhardt said.

The month of March for northcentral and southcentral Montana was the warmest in 30 years.

“Generally, when you get warmer conditions, you also get drier conditions,” Bernhardt said.

Summer of 2015 was Kalispell’s driest on record. The airport weather station registered just 1.09 inches of rain in June, July and August. That easily broke the previous record set in 1910 when 1.4 inches fell.

The Flathead Valley ended the year with only 68 percent of its normal precipitation: 11.63 inches compared with an average of 17.

At West Yellowstone, a gateway community to Yellowstone National Park in Gallatin County, the snowfall total last February was 4 inches, the lowest on record.

Dillon’s January 2015 precipitation of a trace tied the driest on record.

March precipitation in Great Falls was the second driest on record, and the driest since 1916, and the month of June was the city’s driest ever.

While the first half of 2015 was dry and warm, the second half brought an abrupt change and more precipitation.

The final four months of the year were the wettest four months on record for much of central Montana, Bernhardt said.

As a result, annual precipitation in Great Falls ended up at 15.69 inches, which is almost an inch above normal.