December 2025 Summary

A very cold and snowy December

During the first half of the month the temperature was very cold, with many daily lows more than ten degrees below average.  The second half was warmer and actually a bit above average.  However, with the cold start, the overall temperature was a bit more than 3 degrees below average, making it the second coldest December in the last 20 years (the coldest was 2017).

There was also an interesting spike in the temperature early in the morning of the 29th where it went from 0.8°C to 8.9°C in an hour, then down to 4.8°C an hour later and well below zero a few hours after that.

The precipitation for December was going along mostly average before the almost 50 mm on the 28th pushed the total to 113.2 mm, well above the average of 72.1 mm.

There was a little less snowfall this month than the previous month, but the 54.5 cm was still well above the average of 30.7 cm and the snowiest December since 2008.  With two months of very high snowfall, the total so far this snowfall season of 113.5 cm is well over twice the average of 41.8 cm.  Also, since we haven’t had any mid-winter thaws, most of that snow is still around.

Summary for December 2025:

Maximum Temperature 8.9°C
Minimum Temperature -23.1°C
Average Daily High Temperature -0.7°C (Long term average 0.7°C)
Average Daily Low Temperature -11.1°C (Long term average -5.9°C)
Total Precipitation 113.2 mm (Long term average 72.1 mm)

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

November 2025 Summary

The second snowiest November with average temperature and precipitation

It was never really warm or very cold during November, although there were a couple of cooler spells that resulted in the average for the month being 0.7 degrees below average (but this is within the average range).

A large snowfall at the end of the month brought the total precipitation up to 82.4 mm, not too far above the average of 71.9 mm.  However, it was still the second wettest November in the past decade.  The total precipitation for the year of 830.0 mm is just a whisker below the average of 832.9 mm.  

Not only did we have a very early first snowfall on Nov 9, but also over 30 cm on Nov 28.  This put the total for the month at 59 cm, well above the average of 11 cm and more than any November snowfall in recent history.  The only November I could find with more was way back in 1950 when they had 105.4 cm, including an impressive 61 cm on Nov 24.

Summary for November 2025:

Maximum Temperature 13.4°C
Minimum Temperature -6.6°C
Average Daily High Temperature 6.3°C (Long term average 7.2°C)
Average Daily Low Temperature -1.2°C (Long term average -0.8°C)
Total Precipitation 82.4 mm (Long term average 71.9 mm)

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

October 2025 Summary

A warm and dry October

After a hot start to the month, with temperatures getting close to 30°C, the rest of October was pretty close to average.  But this warm start to the month was enough to put the overall temperature a little more than a degree above average, putting it into the above average range.

The temperature first went below zero at 4:30 am on October 9, about 5 days later than the average.  The growing season is defined as the time between the last below zero temperature in the Spring to the first time it happens in the Fall.  This year the growing season was 153 days, less than the average of 160 days.

It was very dry during the first half of the month and although the second half saw some more precipitation, the total for October was only 49.8 mm, well below the average of 81.0 mm.  This was also reflected when looking at the daily totals where the wettest day only had 11.6 mm of precipitation.

This dry month put the total for the year of 747.6 mm very close the average of 750.6 mm.

Summary for October 2025:

Maximum Temperature 29.2°C
Minimum Temperature -3.1°C
Average Daily High Temperature 16.2°C (Long term average 14.2°C)
Average Daily Low Temperature 4.7°C (Long term average 4.6°C)
Total Precipitation 49.8 mm (Long term average 81.0 mm)

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

September 2025 Summary

A hot September that started out dry and then got wet

Although there wasn’t a day above 30°C in September, there were still lots of very warm days in the middle of the month, resulting in an overall temperature that was one degree above average.  But there was quite a contrast between the daily high temperatures (2.6 degrees above average) and the daily low temperatures (0.6 degrees below average).  In fact, the average daily high temperature of 24.6°C was the third highest for September in weather records in the region.

With only 10 mm of rain in the first 20 days of the month, it was looking like it could have been one of the driest Septembers on record.  But then we received 44.8 mm of rain on the 21st, which was the fourth wettest September day in the 25+ year history of the E.D. Soulis memorial weather station.  This was followed by a few more wet days, resulting in a total for the month of 88.0 mm, which is above the average of 75.6 mm.

The total precipitation so far this year is now 697.8 mm, just a bit above the average of 683.5 mm.

Summary for September 2025:

Maximum Temperature 28.8°C
Minimum Temperature 3.8°C
Average Daily High Temperature 24.6°C (Long term average 22.0°C)
Average Daily Low Temperature 9.7°C (Long term average 10.3°C)
Total Precipitation 88.0 mm (Long term average 75.6 mm)

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

August 2025 Summary

A dry month with average temperature and the hottest summer in 70 years

The month started out very warm, but this ended on the 16th with the temperature going back closer to average for a week and then the month ending with a week of below average temperatures.  All of this resulted in an overall temperature that was 0.3 degrees below the average, which is still within the average range.

August also started off very dry with less than 5 mm falling in the first half.  There were a few wetter days in the second half, but still the total only got up to 46.2 mm, which is well below the average of 66.5 mm.  This brought the total precipitation so far in 2025 (609.8 mm) back closer to the average (596.0 mm).  

As we are now past meteorological summer (June-July-August) we can say it was a very hot summer.  The temperature was over one and half degrees above average, this makes it the hottest since 1955 and the fourth warmest in the history of weather records in the region which go back to 1914.  There were 34 days above 30°C which is much more than average of 11.  While the total precipitation of 230.6 mm was just a bit above the average of 214.8 mm.

Summary for August 2025:

Maximum Temperature 32.6°C
Minimum Temperature 5.3°C
Average Daily High Temperature 25.9°C (Long term average 25.6°C)
Average Daily Low Temperature 13.3°C (Long term average 14.2°C)
Total Precipitation 46.2 mm (Long term average 66.5 mm)

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