Sunday, February 2, 2025

January 2025 Summary

A cold and dry January, but with lots of snow

With the coldest days we have seen since February of 2022, it follows that January was below average by a little over one degree.  The temperature went below -20°C for three days in a row between the 20th and the 22nd, that hasn’t happened since January of 2022.  This is the first month that was in the below average range since August 2023.  

The total precipitation of 47.6 mm was much less than the average of 72.0 mm.  However, even though the overall precipitation was less than average, with the cold temperatures we still got 68.5 cm of snowfall in January, which is above the average of 43.7 cm for the month.  Overall for the snowfall season we have had 113.5 cm compared to the average of 95.3 cm for this point in the season.

Summary for January 2025:

Maximum Temperature 2.4°C
Minimum Temperature -22.1°C
Average Daily High Temperature -3.5°C (Long term average -2.2°C)
Average Daily Low Temperature -11.5°C (Long term average -10.2°C)
Total Precipitation 47.6 mm (Long term average 72.0 mm)

(Long term averages based on 1998-2024 data from the Soulis Memorial Weather Station at the University of Waterloo)


Friday, January 31, 2025

2024 Summary

E.D. Soulis Memorial Weather Station at the University of Waterloo Annual Summary - 2024

Clearly the biggest weather story was that 2024 ended up being the warmest year in the history of weather records in the region, which go back over 100 years.  With an overall temperature of 9.45°C it beat the previous warmest year of 2012, when the average was 9.32°C.  It was consistently warm with only August coming in below average and that was only by 0.1 degrees.  This matches the wider trend as 2024 was also the warmest year on record globally.

Locally, the first 3 months of the year were particularly warm with each being 3 or more degrees above average.  This included February which was almost 5 degrees above average, making it the second warmest February on record, just a bit less than the record warmest in 2017.  It was also the most above average for any month also since February of 2017.  March was not quite as much above average, but was still the seventh warmest on record.

The next few months were above average, but not as much as the previous monthss.  April 26 was the last day it went below zero during the spring, this was tied with 2013 as the earliest last freezing day in the history of Soulis weather station.  The lowest temperature seen during May was 3.0°C, this was only matched back in 1975 as the highest low temperature for May. 

June and July were closer to average and then came August which was the one and only month that had below average temperatures.  Of course it was only below by a mere 0.08 degrees, so it was still in the average range.  September was the warmest since 2018, while in October the high temperatures on the  21st and 22nd were 25°C, the only time we have seen a temperature that high that late in October was way back in 1947.

Just before midnight on October 16th the temperature went below zero for the first time since the Spring.  This resulted in the period of above freezing temperatures (sometimes called the “Growing Season”) being 173 days, longer than the average of 160 days but less than the record longest of 186 days.  November was back up to over 1.5 degrees above average, follow by a December that was only above by half a degree, making it the coldest December since 2017.

Turning to precipitation, apart from a dry February, the rest of the first half of the year was close to average.  Then a very wet July included 56.4 mm on the 10th which was the wettest single day in almost 5 years.  But after this, it was dry to very dry the rest of the year, with the combined precipitation of September and October being the second driest for those two months in the region’s history.

The dry fall put the total precipitation for the year at 763.2 mm, well below the average of 869.6 mm, making it the second driest year in the past decade.

The total snowfall for the 2023-24 season was 71.0 cm, which was well below the average of 159.7 cm.  The first few months of the next snowfall season started quickly with 45 cm total in November and December compared to the average of 26 cm by the end of the year.

Frank Seglenieks
weather@uwaterloo.ca
E.D. Soulis Memorial Weather Station Coordinator

Summary for 2024 (averages from 1998-2023 data for Soulis Memorial Weather Station):
Average Daily High Temperature: 14.69°C (average 12.69ºC)
Average Daily Low Temperature: 4.22°C  (average 2.68ºC)
Total Precipitation: 763.2 mm (average 869.6 mm)

Extremes for 2024 (all time Soulis Memorial Weather Station extreme in brackets):
Highest temperature:
33.9°C Jun 19 4:00 pm (35.7 °C July 21, 2011 3:00 pm)
Highest humidex:
44.0 Jun 29 4:00 pm (47.6 July 17, 2013 5:00 pm)
Lowest temperature:
-20.3°C Dec 22 9:15 am (-35.5 °C Feb 16, 2015 7:00 am)
Lowest windchill:
-33.9 Jan 17 9:30 am (-47.3 Feb 15, 2015 6:15 am)
Greatest temperature drop in 15 minutes:
-6.6°C Mar 20 4:15 pm (-9.5 °C July 19, 2013 5:00 pm)
Greatest temperature drop in 60 minutes:
-11.4°C Feb 28 10:45 - 11:45 am (-11.8 °C July 19, 2013 4:45-5:45 pm)
Greatest temperature rise in 15 minutes:
4.4°C Mar 5 1:00 am (8.6 °C Jan 2, 2001 6:15 am)
Greatest temperature rise in 60 minutes:
7.2°C Oct 22 8:30 - 9:30 am (12.2 °C Jan 2, 2001 4:45-5:45 am)
Highest precipitation in 15 minutes:
12.6 mm Jun 26 2:15-2:30 pm (24.8 mm Jul 10, 2020 6:45-7:00 pm)
Highest precipitation in 60 minutes:
19.8 mm May 20 4:30-5:30 pm (57.4 mm Aug 2, 2014 2:30-3:30 pm)
Highest Precipitation in 1 day:
56.4 mm Jul 10 (88.0 mm Sep 22, 2021)
Highest 15 minute average wind speed:
29.9 km/h Feb 26 1:45 pm (44.6 km/h Mar 9, 2002 6:30 pm)
Highest wind gust (only available since 2015):
39.3 km/h Mar 16 2:00 pm (44.4 km/h Apr 13, 2015 2:30 pm)
Last time the temperature went below 0 before the summer:
Apr 26 7:45 am (Has ranged between Apr 26 - May 23)
First time the temperature went below 0 after the summer:
Oct 16 10:30 pm (Has ranged between Sep 19 - Oct 29)
Length of frost-free season
173 Days (Has ranged between 129-186 days)
Highest daily low temperature:
21.6°C Jul 18 (25.3 °C Aug 1, 2006)
Lowest daily high temperature:
-10.9°C Jan 15 (-20.6 °C Feb 15, 2015)
Largest daily temperature range:
22.5°C Apr 9 (29.6 °C Feb 19, 2007)
Smallest daily temperature range:
1.40°C Jan 15 (0.45 °C Dec 7, 2005)

Click on the image below to see the temperature chart:




Click on the image below to see the precipitation chart:





Wednesday, January 1, 2025

December 2024 Summary

An up and down December with average precipitation

The temperature during December was quite the roller coaster ride, with alternating warm and cold periods.  Starting after the first week of the month, it went from 7 degrees above average to 6 degrees below, then back above by 9, below by 10, and ending up 10 above in the last week.

Overall the temperature came out to half a degree above average, which actually makes it the coldest December since 2017, showing how warm this month has been in recent years.  

It was looking to be a much drier than average month, but a little over 20 mm of rain on the 29th put the total at 67.8 mm, just a bit below the average of 72.1 mm.  However, it was also a lot snowier than average as we got 42.5 cm, much more than the typical 13 cm for the month. 


Summary for December 2024:
Maximum Temperature 10.4°C
Minimum Temperature -20.3°C
Average Daily High Temperature 1.2°C (Long term average 0.7°C)
Average Daily Low Temperature -5.4°C (Long term average -5.9°C)
Total Precipitation 67.8 mm (Long term average 72.1 mm)