The past few days have not only been hot, but also unusually humid, too. The relative humidity has not even dropped below 45%, nor has the dew point really gone below 15°C at all! During the day, the DP was often above 17°C. Not surprisingly, severe thunderstorms have been rumbling through Central Alberta the couple of nights.
On Saturday, July 17, I saw a storm with what looked like a small rounded RFB with some cloud striations go over Edmonton, as I watched from the river valley. The RFB even seemed to have a small RFD notch. It was probably just becoming a supercell, as the EC radar did seem to confirm some supercellular structure. I did not see any hail, but the rain was quite heavy - up to 20-30 mm. And it was also quite electrified, too - with CGS roughly every 5 seconds or so.
Sunday July 18th was also hot and humid, too. I caught a very unmistakeable supercell on Environment Canada's radar during the late late afternoon not far from Whitecourt, AB. It was fairly large and had a large V-notch and a hook echo. That same supercell was also warned as having 2-3 cm hail (ping pong ball size) and was also splitting in two. A large thunderstorm (I don't think it was the same supercell that I caught on radar earlier that afternoon) also went just south of Edmonton, so I was able to see that thing to the south. It was lightning-active, with many CGs and some of them were forked, but with very little or no anvil crawlers. There was also what looked like an orphan anvil right beside the larger storm - and it was even spitting out a few CGs and ICs on occasion! The orphan anvil later merged with the main storm.
The anvil had mammatus arranged in "rows", and also had that "matted fur" look to it as the setting sun shone on it. Other cells were already blowing up to the west of the main storm and also becoming lightning active, too.
Later that evening close to midnight, INTENSE and BRILLIANT CGs were lighting up the sky to the west, then south and east as another cluster of storms went by. I did witness forked ones several times. Rain fell a couple of times at my place (in downtown), but not as heavily as the night before. On radar, the system to the south may have been a bow echo, with the northern part of it going by Edmonton and the most intense portion to the south going over Wetaskiwin. That southern storm showed some supercellular characteristics.
It is right now (5:00 pm MST) 23°C (73°F) - cooler than yesterday's 29°C (84°F), but the humidity is quite high, at 78% despite it not having rained since this morning. This means the dewpoint is at 19°C! Conditions are overcast at this time of writing. Not surprisingly, today looks like we will see yet more storms.
