Article from weather.com

February 15, 2018

By Brian Donegan and Chris Dolce

Imagine seeing the temperature rise more than 80 degrees in just a few hours, but it’s still cold.

Yes, this really happened Tuesday in Fort Belknap, Montana, thanks to Chinook winds causing the temperature to rise from an early-morning low of minus 37 degrees to an afternoon high of 45 degrees, a temperature change of 82 degrees in less than 24 hours. Fort Belknap is in northern Montana, about 135 miles northeast of Great Falls.

Chinook winds are the result of an airmass rising over mountain ranges – in this case, the northern Rockies – and as the air reaches the ridge tops, it begins to sink and warm as it descends the mountain slopes. The winds that result can be strong and gusty and can also create dramatic temperature changes.

Temperatures in Fort Belknap rose 23 degrees in just one hour from minus 2 degrees at 7:18 a.m. to 21 degrees at 8:18 a.m. Tuesday morning. Then, a 16-degree rise was observed in an hour from 17 degrees at 11:18 a.m. to 33 degrees at 12:18 p.m.

Fort Belknap saw an 81 degree temperature change yesterday with a morning low temperature of 37 below zero followed by an afternoon maximum temperature of 45 (above zero). #mtwx #chinook pic.twitter.com/1eaBrpH0Kx

— NWS Great Falls (@NWSGreatFalls) February 14, 2018

Earlier this week, Chinook winds led to the issuance of a blizzard warning in parts of Montana even though no new snowfall was expected. Wind gusts up to 65 mph were expected to cause whiteout conditions in blowing snow, likely resulting in blizzard conditions. This is sometimes referred to as a ground blizzard.

The appropriately named town of Chinook, Montana, saw a temperature rise of 40 degrees in one hour and 31 degrees in 15 minutes Tuesday morning as westerly Chinook winds developed.

The temperature at Chinook, MT rose 40 degrees in one hour between 9AM and 10AM this morning and 31 degrees in 15 minutes from 943-958AM as west winds developed. #mtwx pic.twitter.com/KZrwLHfZBV

— NWS Great Falls (@NWSGreatFalls) February 13, 2018

These are just a couple examples of drastic temperature changes over a short period of time. Here are five other incredible temperature swings from past years.

1. 49-Degree Change in Two Minutes

Spearfish, South Dakota, residents bundled up to get the newspaper at 7:30 a.m. on Jan. 22, 1943, with the temperature a frigid minus 4 degrees.

Just two minutes later, the frigid air was not so frigid anymore, as the temperature had shot up to 45 degrees.

That’s right: a temperature increase of 49 degrees in just two minutes.
But wait, that’s not the end of this wild morning weather story. After the temperature climbed all the way to 54 degrees by 9 a.m., it crashed down 58 degrees in 27 minutes back to minus 4 degrees, right where it had started.
The National Weather Service office in Sioux Falls, South Dakota, described the cause of the dramatic temperature changes:

“The wild temperature fluctuations were likely due to cold air and warm air sloshing back and forth along the plains at the base of the Black Hills. A similar effect would be to pour warm water into a shallow bowl of cold water. The water would slosh back and forth a few times before settling down. This is likely what happened with the warm and cold air along the Black Hills.”

2. Record High and Record Low in One Day

Oklahoma City accomplished a rare feat on Nov. 11, 1911.
Warm air ahead of a cold front allowed the afternoon temperature that day to reach a record high of 83 degrees.

The cold front was almost to the East Coast by the following morning, with very cold high pressure taking over the middle of the country.

Then, the sharp cold front sliced through the Heartland and dropped temperatures in an extreme way. Just before midnight, the low temperature bottomed out at a record of 17 degrees. This is a total drop of 66 degrees from the record high to the record low.

Both of these temperature records for Nov. 11 remain intact more than 100 years later.

Springfield, Missouri, was another city that set a record high and record low on this same day in 1911.

3. From 67 Degrees at Lunch to 1 Degree at Dinner

A temperature of 67 degrees at noon on an early-December day might give you thoughts of an outdoor lunch. If you were in Amarillo, Texas, on Dec. 12, 1919, this would have been a bad idea, unless you’re a weather enthusiast.

A powerful cold front raced through the northwestern Texas city during the lunch hour, ushering in cold northerly winds that dropped the temperature to 23 degrees by 1 p.m., an incredible plunge of 44 degrees in one hour.
It got even worse through the afternoon and early evening. In fact, by the time people were cleaning up from dinner around 7 p.m., it was only 1 degree above zero.

4. 110-Degree Temperature Rise in a Week

This next amazing temperature swing from winter 2011 had some residents of Oklahoma changing their wardrobe from thick winter coats to shorts and t-shirts in the span of a week.

A cold airmass, combined with a fresh snowpack and calm winds, allowed the town of Nowata, Oklahoma, to reach a low of minus 31 degrees on Feb. 10, 2011. This was confirmed as the all-time coldest temperature ever recorded in Oklahoma.

Gradual warming accelerated over the course of a week, and temperatures peaked at a record high of 79 degrees on Feb. 17.

According to the National Weather Service office in Tulsa, Oklahoma, this 110-degree temperature rise is the greatest change within seven days in Oklahoma history.

5. 181-Degree Difference in Months

This one is not a major temperature drop or rise in minutes or hours, but rather a very unique occurrence within a matter of months.

On Feb. 15, 1936, the town of Parshall, North Dakota, bottomed out at minus 60 degrees, a new record low for the state. Almost five months later on July 6, the town of Steele, North Dakota, recorded a new all-time state record-high temperature of 121 degrees. This is a temperature range of 181 degrees in North Dakota from February to July in 1936.

South Dakota accomplished a similar feat in the same year around the same dates. McIntosh set a state record-low temperature of minus 58 degrees on Feb. 17. Then, on July 5, Gann Valley set a new record high of 120 degrees for the state (this record was equaled in 2006 near Fort Pierre).

FEATURED IMAGE CREDIT: http://www.cmalliance.org/alife/living-on-faith/

Tags: chinook wind, montana cold, montana weather