Thursday, October 29, 2020

Recent Seasonal Snowfall Totals - Northern Ohio/Midwest/US - Part II

We start the snowfall retrospective with last winter's (2019-2020) snow totals in northern Ohio.

Last year was the 5th straight year with below normal snowfall. The longest stretch of below normal seasonal snowfall was 9 winters between 1963 to 1972. 

Here are the average snowfall totals for northern Ohio. (Color contours are different than the image above)

How about the last 10 winters?  Here are the local snowfall amounts. Colors might be different year to year.













Last year's running snowfall accumulations really tell the story when compared to other years.  (Hat tip to Jared Rennie for supplying these snowfall graphics below)


CLEVELAND


AKRON-CANTON AIRPORT

MANSFIELD

CHARDON

NORWALK

OBERLIN

Snowfall history since 1900. Black line is the 10 years running average.

Snowfall history since 1940

Snowfall history since 1960


Snowfall history since 2000


Snowfall departures since 2000 (red are years below normal. Blue above normal)


Number of days with at least ONE INCH of snow on the ground each winter


Number of days with at least ONE INCH of snowfall


What are the winter with the MOST/LEAST one inch+ snows?
What are the winters with the MOST/LEAST DAYS with at least 1" snow on the ground?


What has been the snowiest decade in Cleveland?


Ohio, Indiana and portions of Michigan saw below normal snowfall last winter. Yet snow was above normal snowfall across Illinois and the upper midwest.

Notice the high snow numbers across the Upper Peninsula of Michigan.


Overall snowfall departures last winter across midwest/Great Lakes. 
The last 5 winters (2014-15 to 2018-19) snowfall vs normal below. Last time Ohio had above normal snowfall was 2014-15.





How about the rest of the country? US snowfall vs normal over the last 6 winters. Purple is above normal snowfall. Tan/brown colors are below normal. (Thanks goes out to Jared Rennie for the images)  Last image is the winter of 2014-15.








Part III of the 3 part series will highlight Lake Erie Ice History...

Monday, October 26, 2020

Recent Winter Temperatures - Northern Ohio/Midwest/US (Part I)

We start off with last winter's temperatures vs normal across North America. Little sign of any cold although early February showed some signs in the central US.

Winter 2019-2020 (Dec-Jan-Feb) North America

US temperature anomalies (standarized) show a similar story month to month

Winter 2019-2020 (Dec-Jan-Feb) US Climate Divisions

Here are the previous 5 winters (Dec-Jan-Feb) for comparison.

WINTER 2018-19

WINTER 2017-18

WINTER 2016-17

WINTER 2015-16

WINTER 2014-15

As for the midwest and Ohio Valley, last winter's temperatures ranked in the top 15 warmest ever across Ohio, West Virginia, Kentucky and Pennsylvania with top 20-30 warmest further west.

WINTER 2019-2020 LOCAL TEMPERATURE RANKS

Here are the previous 5 winters (Dec-Jan-Feb) for comparison. Numbers indicate local climate division rank (1 is warmest. 128 is coldest)


WINTER 2018-2019 LOCAL TEMPERATURE RANKS 


WINTER 2017-2018 LOCAL TEMPERATURE RANKS

WINTER 2016-2017 LOCAL TEMPERATURE RANKS

WINTER 2015-2016 LOCAL TEMPERATURE RANKS

WINTER 2014-2015 LOCAL TEMPERATURE RANKS


Looking across Ohio, the overall temperatures are similar. There are 10 climate divisions across the state. Divisions 2,3,6 and 7 cover northern Ohio.
Division 2,3,6 and 7 make up northern Ohio.  All four divisions last winter ranked top 10 warmest. Each division is below. I also included overall Ohio winter temperatures vs normal.
Winter Temperatures vs Normal - Ohio Division 2

Winter Temperatures vs Normal - Ohio Division 3

Winter Temperatures vs Normal - Ohio Division 6

Winter Temperatures vs Normal - Division 7


Winter Temperatures vs normal - All Ohio Divisions


Here are the top 20 warmest and coldest winters in northern Ohio (Hopkins Airport 1938 to Present/Downtown Cleveland 1871 to 1938)


As for northern Ohio specifically, last winter was very similar to the winter of 2016-17, 2011-12 and 2001-02. 


Here are the winter temperatures vs normal (using moving 10 year averages) since 1960



As I have written many times, most of us don't remember the average of the days we typically remember the extremes.  Here are the number of days each winter we reached a certain temperature threshold since 2000.


Number of Days Above 40 Degrees (Dec-Jan-Feb) out of 90 days

Number of Days Above 32 Degrees (Dec-Jan-Feb) out of 90 days


Number of Days With High Temperatures BELOW 20 Degrees (Dec-Jan-Feb) out of 90 days

Number of Nights BELOW ZERO (Dec-Jan-Feb) out of 90 days

Expanding out the winter list further in time, here are the number of days above 40 degrees since 1940


...Number of night below zero since 1940


Total Number of Winter Days Above Normal Last 20 Years


Most Days Above Normal - Top 15 Winters:

1932  73
1890  68
1882  64
1880  63
1933  62
2002  62
1953  61
1949  60
1992  60
2012  59
2020  59
1954  58
1999  58
2016  58

Here is a graph highlighting the hours the WIND CHILL dropped below a specific threshold over the last 15 winters. I added a few other notable winter of the past for comparison. Last winter is on the left side of the image below.

CUMULATIVE WIND CHILL HOURS LAST 20 YEARS
CUMULATIVE WIND CHILL HOURS FOR SELECT WINTERS IN THE 1990S, 80 AND 70S



...Next post we will cover snowfall history and Lake Erie Ice Cover history