Trashy posted something a couple of days ago stating unequivocably that “no way… is Ottawa getting snow before Christmas day”. The long range forecast on Environment Canada’s website suggests it’s going to be cold enough for snow and the latest aviation forecast suggests there’s going to be periods of snow overnight::

TAF CYOW 221744Z 2218/2318 24007KT P6SM SCT030 BKN100 TEMPO 2218/2220 BKN030 OVC100
FM222000 23005KT P6SM OVC025 TEMPO 2221/2301 6SM -SHSNRA OVC020
FM230100 33005KT P6SM OVC020 TEMPO 2301/2310 4SM -SHSN
FM231000 34012KT P6SM OVC030
FM231500 33006KT P6SM SKC
RMK NXT FCST BY 222100Z=

For those who need a translation, it basically says starting at 4pm this evening (2100Z), there will periods of light rain showers and light snow showers until 10pm followed by periods of light snow showers until 5am tomorrow morning. I suppose there could be a thin layer of snow that hangs around until Christmas but I’m not too hopeful. If you believe the long range forecast, there will be periods of snow on Christmas Day, but it’s still a bit early to tell for certain.

I’ve been dragging myself around today, but I was attributing that to a long day yesterday and not enough sleep. A couple of hours ago I started to feel “out of sorts”, so I checked the Weather Office’s website and sure enough, the air pressure was climbing most of the last day and then dropping fairly steadily since mid-morning.

Given the forecast for the next twenty-four hours, which can be summarized as icky¹, it’s not surprising that the pressure’s dropping.

—

¹ ick·y  /ˈikē/  adj. a meteorological term describing unpleasant weather that typically includes low clouds and freezing rain.

For most of the day, yesterday, I had a headache that just wouldn’t go away. I took a look at the hourly weather observations and noted that the air pressure had been steadily dropping for several hours, as you can see from the graph.

My headache finally started to fade around 1730, after the pressure had stabilized.

I spent some time trying to take pictures of lightning Sunday evening and I had a few successful results, which I thought I’d share with people.

Sunday evening’s lightning VIEW SLIDE SHOW DOWNLOAD ALL

Regular readers will probably remember that I’ve written about the relationship between changes in air pressure and headaches on a number of occasions in the last few years, most recently in January. This morning, a friend of mine mentioned that she started the day with an optical migraine that morphed into a headache.  As it happened, I had a headache coming on at the time, so I took a quick look at Environment Canada’s website and noticed that the pressure over the last 24 hours had been steadily climbing. I took another look a few minutes ago and it seems to have peaked a couple of hours ago.

Taking a look at the surface analysis from 8am this morning, you can see a high pressure over southern Ontario. My guess is that it’s probably moved past us, which is why the pressure is starting to drop a bit. For reference, Ottawa is the red dot and the circle with X is the high pressure, just north of Lake Erie.

Anyone else plagued by headache, migraines or other things that might be caused by this?

My day started well enough:

I suspect that it’s not going to end as well. I’m flying back to Ottawa via Chicago and already my first flight has been delayed by the better part of two hours due to the weather in Chicago. Fortunately, I have a long time between flights, so I should be able to make my connection. Some of my fellow travellers are not as lucky.