Monday, April 3, 2017

March 2017 Summary


A wet March that was colder than February

Somebody better check the calendar because it seems that somebody switched the weather for February and March.  In fact for only the 5th time in the 100 years of records in the region, the average temperature was lower in March than it was in February (the last time this happened was in 1984).

The overall temperature was almost half a degree below average, but this is still within the average range.  However, this was the first time there was an overall temperature that was even a little below the average since April of last year.

It was a wet month with 90.2 mm of total precipitation compared to the average of 61.0 mm.  Interestingly, even with the cooler temperatures, a lot of that precipitation came down as rain instead of snow.  We only got 12 cm of snow compared to the average of 26.5 cm, this brings the total for the season up to 125 cm which is less than the 150 cm average for the end of March.


Summary for March 2017:
Maximum Temperature 17.1°C
Minimum Temperature -15.4°C
Average Daily High Temperature 2.7°C (Long term average 3.6°C)
Average Daily Low Temperature -5.6°C (Long term average -5.6°C)
Total Precipitation 90.2 mm (Long term average 61.0 mm)


(Long term averages based on 1981-2010 data for the Waterloo Wellington Airport)

Saturday, March 4, 2017

February 2017 Summary

The warmest February ever 

In what should not be a surprise to anyone, it was the warmest February that we have experienced in the 100+ years of records in the region.  The first half of the month saw temperatures that oscillated both above and below zero, but it was not until the 18th that the crazy heat came in.  The month ended with 12 days where the high temperature was over zero including some days that were over 15 degrees above the average.

Overall the temperature was 4.4 degrees above average which was almost half a degree more than the previous warmest February back in 1998.  The high of 15.1°C on the 23rd was the highest February temperature we have ever seen in the region, in second place was the 15.0°C which happened the day before.

The precipitation total was 68.0 mm, just enough to put it into the above average range.  Given the high temperatures, it is not surprising that we got about half the average amount of snow during the month (17.5 cm compared to 30.3 cm).  Even though the last 2 months have only seen half the average snowfall, the snowy December means that that the total snowfall of 113 cm is only a little less than the 125.6 cm we would expect at this point in the snowfall season.


Summary for February 2017:
Maximum Temperature 15.1°C
Minimum Temperature -15.3°C
Average Daily High Temperature 3.4°C (Long term average -1.2°C)
Average Daily Low Temperature -5.6°C (Long term average -9.7°C)
Total Precipitation 68.0 mm (Long term average 54.9 mm)


(Long term averages based on 1981-2010 data for the Waterloo Wellington Airport)

Friday, March 3, 2017

2017 Weather Station Contest is on!


The 2017 edition of the UW weather station contest is now on!

Can you guess for the first time the first time the weather station will record a temperature of 20C?

Find out all the details and enter the contest here:

http://weather.uwaterloo.ca/2017_contest/contest.html

Don't delay - you have to enter the contest by Wednesday, March 8th, 2017 at 2:00 pm.

Thursday, February 2, 2017

January 2017 Summary

A wet, warm, and “dreary” January

There were four cold days in the first part of the month, but that was about it for the really cold weather.  As well as a few days in the high single digits we also saw 12 days in a row above zero, which is something that we haven’t seen in January since 1944.  Put that all that together and it is not surprising that overall it was over 3 degrees above average, making it the warmest January since 2006.

With the 111.2 mm of precipitation in the month it was the second highest total in the last 18 years (2013 had a bit more with 114.7 mm), while most of it (81.4 mm) fell during the very wet first half of the month.  Of that precipitation there was only 20 cm of snow, less than half of the average of 43.7 cm.

Then we get to the “dreary” question.  The background is that at the UW weather station we measure the amount of incoming solar radiation, which is correlated to the number of hours of sunshine but not technically exactly the same thing.  Also keep in mind that this is the only source of this kind of data in the area, so records only go back to the start of the weather station in 1998, unlike precipitation and temperature which have records going back to 1915. 

So based on what we measure, the overall average of 47 Watts per square metre of incoming solar radiation was the lowest January value in the history of the station and much lower than the average of 81.7 W/m2.  Also I made an arbitrary and non-scientific criteria that if a day never had a reading of over 200 W/m2 then it was a “dreary” day.  Using this, the number of dreary days we had was 13 this January putting it well above the average of 7.5 and again the most we have seen in that past 19 years.


Summary for January 2017:
Maximum Temperature 8.2°C
Minimum Temperature -20.9°C
Average Daily High Temperature -0.1°C (Long term average -2.6°C)
Average Daily Low Temperature -6.4°C (Long term average -10.3°C)
Total Precipitation 111.2 mm (Long term average 65.2 mm)

(Long term averages based on 1981-2010 data for the Waterloo Wellington Airport)

Sunday, January 22, 2017

Longest January streak of above zero days in a while

As of January 22nd we have had 8 days in a row of days with above zero temperatures and the current forecast is for 4 more.  If we get to 12 days it will be longest streak of above zero days since we had 13 back in 1944 from Jan 19 to 31.

Note that this only counts days in January, for instance 2007 started with 8 days above zero, but this was after 23 to end off 2006, so the total streak there was 31 days, just not all in January.

Tuesday, January 10, 2017

2016 Summary

University of Waterloo Weather Station Annual Summary - 2016

Considering that April was the only colder than average month during the year, it is not that surprising that 2016 came in as one of the warmest we have seen in the 100 years of weather records in the region.  Overall the average temperature was 8.69ºC putting it behind only 2012 and 1998.

The year started off in the middle of the very warm winter of 2015-16 resulting in the first 3 months being all warmer than average, this included a high temperature of 14.2ºC on the third of February which was the highest February temperature we have seen in the region.

Things turned around in April with the only colder than average month of the year that was also the fourth coldest April in the region’s weather records.

The warm end of the Spring in May transitioned into the hottest summer we have had since 1955 and the third highest overall.  The 19 days above 30ºC during the summer contributed to the 27 we had in total for year, this is much more than the average of 8, but much less than the 49 we saw in 1955.

This then continued into the fall with September to November all coming in at over 2.5 degrees higher than average including: September being the warmest since 1959 and the fifth hottest overall and November the sixth warmest and the most days over 10ºC at 20.  But as we have seen a lot of warm Fall seasons lately, this Fall wasn’t that significant even these really warm temperatures.

As often happens there were wet and dry months during the year, for 2016 the year started with a few average months for precipitation.  Then March came in over twice as wet than average, but this quickly changed as for the most part it was a very dry summer.  It would have been historically dry if not for a 10 day period in August when almost 150 mm fell, this resulted in August being the 7th wettest all time.

For the rest of the year we saw pretty much average precipitation which helped in putting the final total within the average range.  The final total came in within the average range at 891.0 mm, which is a little below the average of 916.3 mm.

As for snowfall, we saw 100.5 cm of snow since the beginning of January, which is about average for that time of year.  But the 75.5 cm in the second half of the year (mostly from December which saw almost twice the average for the month) put the total for 2016 of 176.0 cm which is above the annual average of 159.7 cm.

So the final story of 2016 is the overall heat during the year and how dry it was during most of the summer.  But there wasn’t a whole lot in terms of extreme events, in fact in the list of extremes that are listed on the next page there was not one that was exceeding during this past year (of course this will get harder as more data is added to the record, but usually we have seen at least one or two extremes every year).


Summary for 2016:

Average Daily High Temperature: 14.10°C (average 12.05ºC)
Average Daily Low Temperature: 3.28°C  (average 1.94ºC)
Total Precipitation: 891.0 mm (average 916.3 mm) 

(averages are calculated from 1981-2010 data for the Waterloo-Wellington Airport)
Click on the image below to see the temperature chart:

Click on the image below to see the precipitation chart:

Tuesday, January 3, 2017

December 2016 Summary

A wet and snowy December with average temperature 

There was a much colder than average week in the middle of December that was offset by a warmer start and finish to the month, resulting in an overall temperature of 0.3 degrees above average.  This put the month within the average range for only the second time this year compared to 1 below average month and 9 above.

The precipitation was nicely within the average range for most of the month, but a few storms in the last week (including the rain on Boxing Day) resulted in the total finishing above average.  The total of 91.0 mm was well above the average of 71.2 mm.

With a total snowfall of 73 cm, it was the snowiest since 2008 (when we had 95.5 cm) and almost double the average of 37.2 cm.


Summary for December 2016:
Maximum Temperature 8.6°C
Minimum Temperature -14.9°C
Average Daily High Temperature -0.3°C (Long term average 0.2°C)
Average Daily Low Temperature -5.6°C (Long term average -6.8°C)

Total Precipitation 91.0 mm (Long term average 71.2 mm)

(Long term averages based on 1981-2010 data for the Waterloo Wellington Airport)