Observations

We had quite the rain storm the other night here in Halifax. My personal gauge recorded 75.6mm/hr at one point, around 6:10am. It certainly felt somewhat “tropical”, none of the little leaf shreds from next level winds but the rain rate was intense.

I have two weather stations on site, you can see the difference here between a tipping bucket unit (the WS-2902-D) and the haptic sensor in the GW2000. I didn’t have the chance to calibrate the 2000 for that kind of rain, perhaps now I have a guide post, but the 2902 has always been pretty solid and reliable and matches other units in the vicinity after an initial round of calibration.

I took a few screenshots of the storm from the Environment Canada website at the time, with details on the cell.

The current conditions run for the time in question:

You can see there’s that one bullseye in the radar return there over 64mm/h, in the red, and that must’ve been it, though it must’ve been in the process of dying out because the 55+mm rain totals petered out shortly thereafter.

Here are the totals after the fact from PWS stations measured against official local readings.

Something that totally caught my eye watching this front pass was what happened to the ocean temperature afterwards. It’s been somewhat balmy as of late ocean-temperature-wise, 15 or above on the Atlantic side, and yet as the land warmed in the sun on Sunday the ocean water temperature dipped significantly, 6 degrees in 12 hours, three degrees in just a two hour window within that 12 hours! Waves picked up, the wind switched to the SW and the temperature dropped like a rock. It recovered somewhat soon after… A dynamic environment to say the least, I had no idea ocean temperature changed so quickly, thinking of it as a more uniform thing, slowly morphing over time. With enough turbulence it’s clear, whatever “warmth” is there, it isn’t very deep.

Here’s the story from the official plot, fascinating.

The winds at the time:

At the Provincial level: