That's More Like It!

24 degrees for a high...now that's more like it. The heat wave finally ended today as a cold front pushed through the region bringing with it some much needed rain. With all of the moist, humid air that was in place Environment Canada was a little concerned about the potential for very heavy rain. A rainfall warning was issued but the rain, although heavy at times, did not amount to a staggering figure. The rain was needed though and did its part in cleaning up the air that had become very polluted over the last few days. The never ending smog advisory was finally lifted today as all of that excess carbon has been flushed from the atmosphere and will most likely be end up as "rain dust" on your car. The most noticeable change associated with this frontal passage will be the "cool down." The thing you have to remember about cold fronts is that the term "cold" is relative. They should be called "relatively cold fronts." Temperatures to the west of that front are still above seasonal but are cooler than the 33 and 34 degree highs we've been subjected to over the last few days. Luckily, how hot it "feels" when you step outside and has more to do with the "dew point temperature" which look to drop in a big way.
















The Dew Point is the temperature you have to lower a parcel of air to for dew to form or for 100% relative humidity to occur. The higher the dewpoint the more humid the air and the hotter it feels. Looking at the map above you can see the difference in dewpoint temperatures between Peterborough and Sudbury. Since the cold front moved through Sudbury well before Peterborough the humidity there was lowered and the dew point temperature was only 13.5 degrees (shortly before 5pm). Peterborough's dew point was an even 21 degrees. Although it was 27 degrees in Sudbury (compared to 23 at that time in Peterborough) it actually felt warmer here in the "Peter Patch." With the humidity it felt 32 here compared with 30 degrees in Sudbury despite the 4 degree difference with the actual temperature. It is the lack of humidity and lower dew point temperatures that we can really look forward to over the weekend...enjoy!

Heat Wave!

I think this picture says it all. Andrea sent this picture in from Pandy Bear’s Bed & Breakfast in Fenelon Falls. It may look frightening but keep in mind that thermometer is likely a little off. Direct sunlight or even heat radiated from your home can affect a thermometer’s accuracy but with the humidity it at least felt that warm stepping out of the house. This has been a hot stretch of weather to say the least. The warm-up started on Saturday. After a cool Canada Day (Thursday) and a seasonal Friday we shot up to 29.7 degrees on Saturday afternoon. Saturday was followed by a 31 degree high on Sunday (30.8 degrees) and the hot streak continued from there. Even though the hot weather started on Saturday the “heat wave” did not officially start until Monday as Environment Canada defines a heat wave as three consecutive days in excess of 32 degrees. Monday’s high was 33 degrees as was Tuesday’s. With today’s high exceeding 32 degrees (with humidity feeling into the 40’s) what we have been suffering through can now “officially” be called a heat wave. A heat wave that does not look to end until Friday. Friday’s high is expected to top out in the low to mid twenties and some much needed rain is also expected. There is light at the end of this long, hot and muggy tunnel.

What is the Humidex?

Today was a hot one! By 9am is was 29 degrees and by 3pm we topped out at 33 degrees. As hot as it was, the heat was not the big story today, it was the humidity. You may have heard me talking about a "humidex" value in the 40's today or that it actually feels over 44 degrees today (which it did). If you've ever asked yourself why does humidity make it feel warmer or "what the heck is the humidex?" Well, hopefully this video helps to answer those questions...