May 25 - A wet day across the continental divide and a visit from Bjørn

NIPIKA​

Light rain throughout the day

​On our way to Nipika we decided to do a carsonde, however no transition was observed. Light rain was observed through the Sinclair Pass and within Kootenay Valley. The drive was stunning with the low cloud in the valley.

We arrived on site and started our first observations at 1620 UTC. There was light drizzle, with some light precipitation happening prior to our arrival, 

The buzz and cheer from bystanders and contestants of the Crazy Soles Nipika Race could be heard from the site every so often.

Probably the most exciting thing we found was our time-lapse camera which was found on the ground and the stake that held it there bent into the shape of an S (see picture below). Charlie played the detective role, determined to find the culprit of our fallen camera (don't worry it's still in great condition!). It happened to be a trailer that passed by, which accidentally knocked it over. The camera landed facing upward, giving us a few hours of beautiful clouds passing over Nipika. Selina quickly started working on getting a new stake up for our time-lapse camera. 

Precipitation throughout the morning was light overall. The clouds were often midway up the mountain ranges on both sides. However, as all the models predicted, higher precipitation rates would occur in the afternoon, which were observed from 1840 UTC to 1920 UTC, with an intensity from 1.5-3. The parsivel was recording light rain during the highest intensity periods. This is fairly high given how dry conditions we have observed over Nipika thus far. 

Precipitation ended at 2000 and we remained on site till we finished observations by 2200 UTC, with intermittent rays of sunshine striking our station. Radar was showing no precipitation heading towards us and the latest models were showing diminishing chance of precipitation over our area. 

- Juris

Field Participants: Selina Mitchell, Charlie Hébert-Pinard, & Juris Almonte

FORTRESS​

Perfect day for making a snowman

An early morning phone call from Juris woke me (Hilary) up and after a brief discussion, it was decided that a team would head out to the site at fortress. I woke up Cécile and we were on the road by 1130 UTC.

It rained on the way and we did a car sonde on the way up the road at 1200 UTC where we were able to observe a transition region. Once we arrived at the top, precipitation was mixed about 50% snow 50% rain.

Cécile took the first round of observations and observed some moderate snowfall, sometimes mixed with rain. Temperatures were around 2°C, which made it too warm to take macrophotography pictures of the very large aggregates of wet snow.

I took over observations and observed very large aggregates (> 1 cm) of rimed dendrites. Snow was still very wet, but definitely not mixed. (Perfect snowman making snow!) I could feel it getting colder outside so I was able to start taking pictures. The snow particles became smaller around 1620 UTC and we saw various particles such as columns, plates, and dendrites.

​Aurélie and André came to replace us at 1800 UTC. Cécile and I conducted another car sonde on the way down Fortress Road and were able to catch another transition region!
 
-Hilary

Aurélie and I arrived at the Fortress site at 18:00 UTC. By the time we arrived there it was snowing moderately, but with an incredible variety of different unrimed and lightly rimed hydrometeors – dendrites, irregulars hydrometeors, aggregates, columns, capped columns, plates, and 12-branches. The snowfall kept varying around moderate intensity during the afternoon until late afternoon (23:30 UTC) when the intensity started to decrease to light. With the decrease in intensity, the hydrometeors changed abruptly to unrimed and lightly rimed needles and some very isolated columns.

Interestingly the weather radar was not showing any precipitation over us, perhaps the shape of the needles and columns are not reflective enough to the radar beams.

The lower clouds cleared abruptly with the end of the precipitation event, however the sky was still cloudy above, with clouds’ base around the same height of the peaks surrounding our research site. After making sure that event was over, we went to the Powerline station to make sure the Pluvio weighing gauge and the MRR-2 installed there were working and everything was okay.

- André

 
​Field Participants: André Bertoncini, Aurélie Desroches Lapointe, Cécile Carton & Hilary Smith 

Nipika

Fortress