Thursday, February 02, 2023

How Does The Christmas 2022 Blizzard Compared to the January 1978 Blizzard?

Just last week we remembered the Blizzard of 1978 or the White Hurricane as it would be known as after the fact. Ohio turnpike was shutdown gate to gate.  Twenty foot high snowdrifts. Wind gusts above 80 mph in spots across Ohio and beyond.  If you lived during the storm, the memories will live forever.

A blizzard is defined as three hours of sustained winds of 35+ mph, 1/4 mi or lower visibility due to blowing and/or falling snow.  The last condition is key as you don't need falling snow for a blizzard to occur.  Recently the Blizzard of Christmas 2022 created conditions that in some respects rival the '78 blizzard.  Below is a comparison between the initial 12 hour period for each blizzard. The data includes precipitation type, temperature, wind chill, wind direction, speed and gusts followed by air pressure from Cleveland Hopkins Airport:

A few elements stand out here.  You'll notice the wind chill values of the 1978 storm are greatly reduced compared to what many publications sited years ago. The wind chill calculation changed in 2001 to reflect new science on the subject of heat loss on the body.  Earlier estimates put the wind chill at under -60° but in reality, the chills probably bottomed out at -30°,  maybe -40° with the higher gusts with the new formula.  Other notable findings from the observations above:

* The temperature drop during the December 2022 storm was greater (42° to 0° in 8 hours).  The 1978 storm had a sharper drop. 43° to 9° in 5 hours.

* 2022 storm created wind gusts nearing 50 mph at Hopkins with some reports above 60 mph once the temperatures dropped into the single digits.  These wind gusts (50+ mph) took roughly 5-7 hours to reach after peak temperatures. The 1978 storm had gusts reaching 70+ within 3 hours of peak temperatures

* Official wind chill values were LOWER during the 2002 storm.

* 1978 storm was far deeper with lowest air pressure at 958 mB vs 993.0 mB with the 2022 storm.

* Snow depth was much deeper in 1978.  16" before the storm versus no snow on the ground at the start of the 2022 storm.

What about the conditions after the initial 12 hours?  Here are the hourly observations for each storm over the next 48 hours. 2022 storm on left.  1978 storm on right. Color coding is identical to the image above.

Here are some notable findings in these 48 hours

2022 storm:

* Temperatures remained below zero for another 12 hours and under 10 degrees for another 19 hours.

* Sustained wind speeds stayed at 30 mph for 12 hours with gusts near 40 mph for 24 hours.

* Wind chills remained at under -20° for 24 another hours.

The progression of the arctic cold was fast and widespread. After 7 days the extreme cold had faded.

7 day temperatures vs normal during and following blizzard

1978 storm:

* Temperatures never dropped below zero; remained below 10 degrees for only 9 hours

* Sustained winds were similar to the 2022 storm (30 mph for 12 hours) with 40+ gusts 

Wind chills stayed between -5° and -15° as temps stayed between 5° and 15° degrees

The cold following the '78 blizzard was just as harsh and quick but it lingered much longer.

7 day temperatures vs normal during and following Blizzard

The surface features with both storms look very similar.

January 1978 Blizzard

December 2022 Blizzard

Psychology tells us that our experiences especially during extreme events tend to leave a stronger mark in our mind more than more benign events.  The January 2022 blizzard was one of those events.  The blizzard around Christmas 2022 was also a memorable one--certainly not the worst in northern Ohio history but it's on the list (maybe top 5)--and should be remembered in the same breath as the '78 storm.