NIPIKA

2 hours of rain and nothing more

​Aurélie, Jeremy and Juris headed out from the RHS at ~9:20 MDT. On the way we observed rain along the Sinclair Pass, again close to the Kootenay Valley viewpoint. Part way down Settler’s Road rain started to occur. We arrived on site at 10:00 MDT with some heavier than typical rain intensity. Temperatures felt a lot cooler with more moisture in the air - a stark difference from yesterday on site. Observations began at 16:00 UTC and at 16:30 UTC, I observed the highest intensity of rain I have seen here so far. With discussion with Aurélie and Jeremy we settled on an intensity of 3. Oddly, the parsivel still called this light rain. Both Aurélie and I were a bit surprised, as we decided that the parsivel at Fortress would have recorded more than -Ra, given this intensity. After discussion with the rest of the team at Fortress we determined that the METAR code that the parsivel outputs might not be the best indicator of intensities and we will need to stick to the raw spectra data.

It was overcast for the full duration of my two hour stretch of observations, but the clouds would become darker and lower, or the opposite and would lift and brighten.  Overall, I noticed more midlevel nimbostratus clouds. At 1730 UTC I could see looking to the SW over the Stanford range that clouds were forming on the base of the mountain, within the next few 10 minute time steps these clouds quickly rose moving along the range towards towards the N. This made sense as the anemometer was showing winds coming from the S. 

Looking at 1828 UTC I observed the same phenomena with clouds moving alongside the Mitchell Mountain Range heading N. By the end of my observation shift, precipitation ended. During Aurélie’s stretch of observations (1810 to 2000 UTC) weather conditions remained very similar at the site. Negligible to light winds coming from South were observed, along with an overcast sky, darker toward south and little brighter at Mitchell range.
​
- Juris

As observed earlier by Juris, some well defined low level clouds moving from south to north were noticed alongside Stanford mountain. On the opposite direction, low level clouds were also forming toward Mitchell range, optically thin at the beginning. They reached the same thickness and were white and opaque in colour.

- Aurélie

Despite the lack of rain, the team was able to work on a few things. The time-lapse camera was moved to a new location, now facing NW, with a good view of all the instruments including the trailer and solar panels, with the Stanford range in the background. Aurélie reorganized and cleaned the truck.

- Juris

​Recent Geonor weighing gauge data was inspected following yesterday's re-leveling. Leveling resulted in slight shifts in offset for frequency and the subsequent depth values between sensors, however the range of measurement across sensors remains unchanged. Further site visits will require an eventual re-calibration and estimation of the apparent accumulation caused by thermal fluctuation in the sensors. 

- Jeremy

Our last observation was taken at 2310 UTC and by that point the cloud cover had lifted, and it was noticeably warmer with the sun rays shining through the cloud.

​- Juris

Field Participants: Jeremy Morris, Aurélie Desroches-Lapointe & Juris Almonte

FORTRESS 

A grey and rainy day

Charlie and I (Hilary) arrived on site at Fortress around 1550 UTC to start taking observations at 1600 UTC. It rained on the way along the highway with varying intensities (sometimes moderate-heavy), but by the time we reached the Fortress gates it was light and was light all the way up the road. Rain was variable throughout the day – generally light to moderate, but at times heavier. Rain stopped around 2210 UTC and we took our last observation at 2300 UTC.
​
- Hilary
 
Field Participants: Hilary Smith & Charlie Hébert-Pinard 

NIPIKA

A hot day on site

With a switch in personnel at Nipika yesterday (Jeremy and Aurélie now on site), we all opted to take advantage of the hot weather to do a full site orientation; going over protocols, checking up on the instruments and doing a full data download. 

Prior to leaving Radium Hot Springs, Silver Star radar was showing convective cells to the south of the radar, though we were unable to see any Cb clouds from the valley. Skies were blue with scattered cumulus clouds. We (Jeremy, Aurélie and Juris) arrived at Nipika for 2147 UTC.

The instrumentation at Nipika was in fine form upon initial inspection. Juris provided Aurélie and Jeremy with an overview of site operations before the team got to work conducting data downloads and inspecting sensors. Data from the MRR and disdrometer, and timelapse images were collected. Weather station data downloads were conducted and all sensor outputs inspected. It was determined that the snow-photography booth was unlikely to see further use and therefore was dismantled. 

Time was taken to inspect the Geonor all-precip weighing gauge to determine causes for variance across transducers, and subtle spikes in output. The collection bucket was levelled via sensor height adjustments to ensure each transducer shared equal weights from the bucket. All wiring was inspected for loose connections, none were found. The group identified the location of each sensor with respect to sun exposure, which was deemed not to be the cause of spikes given that sensor 1 (the spikiest) was the most northern unit. Review of existing research on thermal sensitivity of Geonor transducers will further determine an approach for managing the diurnal noise in depth measurements. Lastly, sensor calibration tests will likely be conducted to ensure the frequency-depth calculations are being offset properly.

The team finished up there, and dipped their toes in the Kootenay river before hitting the road. While travelling to Radium, some convective precipitation was observed at Kootenay valley view point (highest point of drive) and spotted some darling ursine beasts along the way.

-Jeremy

Field PEEPS: Jeremy Morris, Aurélie Desroches-Lapointe, & Juris Almonte

FORTRESS
 
A beautiful and sunny day

Charlie and I (Hilary) spent the beautiful day today downloading data and catching up on some administrative tasks. We headed to Fortress Junction around 1600 UTC where we made sure the car was in tip top shape and sat in the sun while waiting for 8 days of data to download. After around 45 minutes, the downloads were completed and we left for our site at the top of Fortress. We arrived and began downloading another 8 days of data. It was a beautiful day at Fortress and the sun was very bright and very warm. It was interesting to see how much snow has melted since the last time we were there – our site looks almost snow free! We ensured that there was ample space left on the brick and double checked the file format of the LiDAR data. We also tried to troubleshoot Cam 26 and make sure that all the cords were properly connected, however it still wasn’t working - we couldn’t figure out an obvious solution to this problem and decided to leave it in case we messed up Cam 27. After the downloads were completed with our instrumentation, we went towards the powerline instrumentation where we downloaded the MRR data and made sure that everything was plugged into the shed.

Once all of our tasks were completed, upon Mel's suggestion, we walked up to the ridge overlooking Fortress. It was still very snowy but it was lovely view of our surroundings. We saw some beautiful views of the mountains that surround us that we can't see from our trailer because of the buildings and trees. We even saw our little trailer and research site! It made us realize that we take for granted the stunning area in which we are so privileged to be working. 

We left Fortress to head back to BGI around 2030 UTC. At BGI we backed up and uploaded the data to google drive.
 
It’s a big relief to have all the data up to date and that all instrumentation is working after a few days not in the field!
 
-Hilary
 
Field Participants: Hilary Smith & Charlie Hébert-Pinard 

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

Convective storms all around, except for the valley​

We arrived with cumulus clouds overhead. It was evident that we had a bit of precipitation overnight given some muddy sections driving into the site on km 14 of Palliser road.  Selina confirmed this by looking at the geonor data, which showed amounts of ~1.4 mm around 0600 am MDT.

The whole day was spent watching a variety of cloud types, including Cumulonimbus, nimbostratus, cirrus and towering cumulus, 

Little precipitation was observed at Nipika, with very light precipitation beginning around 1720 UTC and occurring intermittently till around 2010 UTC. Precipitation rates never increased above an intensity of 1. We did observe precipitation on the slopes of the Mitchell Range (East) and with more over the Stanford Range (West).

Throughout most of the afternoon clear blue skies were observed overtop of our site within the valley. This blue sky gap in the clouds fluctuated in width between the two mountain ranges. Many times we thought the cells would make their way towards us, but alas, they would appear to dissipate and virga was observed before the cells reached us. For the most part, winds would fluctuate between westerly and northerly. Though winds were often calm within the valley, there were also some gusty moments likely from outflows of the storms.

Tomorrow there will be a race in the area which will bring  around 200-300 people to the Nipika area. We had a public visitor who had stopped by during a training session. It was delightful to know that he was a fellow earth scientist, who had completed his MSc in glacier hydrology at the University of Calgary - what a small world!

- Juris Almonte

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

FORTRESS

Convective storms, no snow 

Yesterday André & I went back to Alberta, after many days spent at Nipika. 2 hours only after our arrival at BGI, we were ready to take our first nightshift, as a convective storm was supposed to bring precipitation over Fortress that night, and possibly the 2 following days.
On our way to Fortress, we made a carsonde, but we didn't find any transition zone. There was no more rain when we arrived on site.
We started taking observations at 05.00 UTC. During the night we observed a light rainfall starting around 06.00 UTC, and increasing to become moderate around 08.30 UTC, before finally ending around 09.20 UTC.
With nothing else visible on the radar, we decided to stop taking observations at 10.00 UTC and got back to BGI to catch up with some sleep, tired but also a bit frustrated. After missing the snow for so long while we were at Nipika, we were pretty excited about the possibility of finally getting some snow, but we can't report anything else than rain at most moderate during that night.

- Cécile

Hilary and I left BGI on Friday morning at around 1400UTC, observing light rain on our way to Fortress Mountain. Seeing along the way that a few mountain tops were foggy, we did a Car-sonde on our way up the mountain and, at 1433UTC, caught the beginning of a transition at the altitude of 1693m where we observed a small amount of solid/mixed particles among the rain. Mixed precipitation was occurring from that point to the top with increasing amount relative to rain. We started taking observations at 1450 while Fortress top was receiving a mixture of rain, graupel and iced particles. Being at the top until 2300UTC, we witnessed three episodes of precipitation, respectively from our arrival (1440) to 1640, from 1900 to 2020 and finally from 2130 to our departure (2240UTC). This 1st one was characterized with rain mixed with graupel and unrimed partially iced particles mainly at a light-to-moderate intensity. On the 2nd episode, we observed light rain followed by moderate to intense mixture of rain and pellets (iced and liquid core). The 3rd one consisted of lighter rain only, reaching moderate intensity. Negligible to light northerly winds were noticed during the day, often weaker during precipitation. Between those events, we had nice weather characterized by sunny with partially to completely overcast sky. Since we couldn’t take macrophotos, we tried to figure out an efficient way to take close-up pictures with the Olympus camera. Results were good, as we’ve been able to capture small details on fabric and on snowpack. Edges of the pictures were still blurred which suggest that we need a little more practice.

- Aurélie

​André & I went back to Fortress to replace Hilary & Aurélie. We noticed a really heavy rainfall while we were driving to Fortress, but it stopped when we arrived on top of the mountain, and Hilary & Aurélie confirmed that they didn't get any of it.
We started taking observations at 22.50 UTC. After a whole night spent hoping for some snow without any result, we still believed that we could have a chance to get some during the day, as the girls got some just before we arrived. But to our great despair, not only didn't we get any snow, but neither did we get any rain. We kept taking observations for some time, as the radar was showing some important convective cells close to us, but those cells remained very stationary and were diminishing. Moreover the most recent update of GEM 2.5 didn't plan any precipitation for the rest of the day, so we decided to go back to BGI and check the radar from there, just to make sure we wouldn't miss anything. For now (0500 UTC), we still haven't see any major change. We will get up early tomorrow morning, to check what the radar looks like, and get prepared to go on the field, as the storm was originally supposed to be the strongest during that day.

- Cécile Carton

Field participants: André Bertoncini, Cécile Carton, Hilary Smith & Aurélie Desroches-Lapointe

NIPIKA

The SPADE Queen has arrived at RHS

​At 0930 MDT (1530 UTC) Julie arrived for coffee at Nipika. We were delighted to have our first Zoom meeting with Julie in the flesh, no longer was she a voice coming to us from hundreds of kilometres away. After some great conversations, we departed for Nipika at 1115 MDT (1715 UTC), a convoy of two cars threading through a steady stream of ore trucks and forestry vehicles, rushing through work after the holiday weekend. After a great little tour of our trailer and our host of weather instruments, Julie joined us on our outdoor patio for some conversations. As a grand finale, we took Julie to see the now turquoise Kootenay River rushing through a canyon that is located within 200m of our site. At the end of Settlers’ Road we reluctantly bid farewell to Julie and Hadleigh as they drove off to BGI at 1300 MDT (1900 UTC). Stephen, Cécile, and Selina returned to Radium Hotsprings at 1330 MDT (1930 UTC).

-Selina

Field Participants: Prof. Julie Thériault, Prof. Stephen Déry, Cécile Carton, Hadleigh Thompson, & Selina Mitchell.

FORTRESS

​A quick and fast moving storm

​When we looked at the forecast last night, it looked like we would have the day to get prepared for an overnight event the next night. So after having a relaxing morning, we looked at the radar and saw that there was a fast moving storm from SE Alberta moving towards Fortress! At the time it seemed to stall along the foothills of the Rockies. An impromptu decision to head out to Fortress was made, given we had some other errands to run on site. So, we quickly gathered our things and headed towards Fortress. We conducted a carsonde on the way and managed to capture a transition region! Once we got to the top of Fortress, there was light to moderate snowfall. We started taking observations at 1630 UTC on May 21. We saw some very beautiful hydrometeors! There was no riming at the beginning of our observations and so we were able to see the details on the large (~ 5 mm) dendrites that were falling. Snow became light around 1650 UTC, however we still saw some large dendrites and were able to take a few photographs (e.g. side planes). Particles became very heavily rimed as the small storm progressed and we made our last observation at 1800 UTC. After downloading the data at the top, we did a carsonde on the way down and captured another transition region. We stopped at Fortress Junction to download data and then headed back to BGI to prepare for the bigger storm that is still forecast for tonight. Stay tuned!

​-Hilary and Juris
 
Field Participants: Juris Almonte & Hilary Smith 

NIPIKA

A day with steady light rainfall

Cécile and Selina arrived at Nipika weather station at 0700 MDT (1300 UTC) to find an eerily quiet morning shrouded in fog. There was gentle precipitation throughout the morning. Although the fog never lifted entirely, at one point there was a faint outline of the sun, and birdsong erupted from the surrounding forest. The anemometer barely moved throughout the morning, and nor did the researchers as they huddled beneath the tarp in an unusually chilly temperatures ranging from 4-6°C. However, between observations, the researchers did manage to venture a couple hundred of metres to the west to visit a canyon where the Kootenay River was running luminescent green. Cécile and Selina enjoyed some mud bogging on the way to pass the torch to Hadleigh and André at Nipika Resort. The event follows with very light to light rainfall until it stopped completely at 1620 MDT. This event was markedly clearing from the southern quadrant, revealing the fresh snow that fell on the mountains above the Kootenay River valley.

- Selina and André

Field Participants: Cécile Carton, André Bertoncini, Hadleigh Thompson & Selina Mitchell

FORTRESS

A daytime event (May 18 MDT)

For a third consecutive day, Aurélie and I (Charlie) left BGI very early in the morning on May 18 to go into the field. Fortunately, the sun was already up before we left, precipitation was very light (almost negligible), and visibility was way better than the previous day. We even saw some elk on the side of the road during our drive! We started observations as soon as we arrived at 1300 UTC. The snow intensity was light to moderate, the temperature was around -2°C, and the wind was negligible. Conditions stayed fairly constant for the first few hours, which permitted us to observe lots of plates, columns with dendrites, plates or multiple plates, and aggregates of plates. We had a lull between 1730 UTC and 1930 UTC with had only a couple of flakes. It was hard to identify these flakes because they were already partially melted by the time they landed on the velvet pad. During the next hour, the intensity of the snowfall increased rapidly, and gave us lots of graupel and needles, before it stopped completely just in time for the arrival of Juris and Hilary.
 
-Charlie
 
Juris and I (Hilary) arrived at Fortress Mountain to replace Charlie and Aurélie at 2038 UTC on May 18. We saw some rain on our drive from BGI, but it stopped completely by the time we reached the gate at the bottom of the road. When we arrived at the top of Fortress, precipitation was very light, almost negligible. We took over observations from Charlie and Aurélie and observed very small and very heavily rimed dendrites and irregulars. Winds were light from the SE. We were only able to take one photo over the course of our observations. Total precipitation accumulation over the course of the event was 3.6 cm with a SWE of 6.5 mm. We made our last observation at 2300 UTC and then left to head to Fortress Junction to download the data from this event and the previous events, and then to head back to BGI.

It was a very calm ending to a busy few days with lots of precipitation events. 
 
-Hilary
 
 
Field Participants: Juris Almonte, Hilary Smith, Charlie Hébert-Pinard, & Aurélie Desroches Lapointe 

​NIPIKA

May 16 & 17 (MDT)
 
We left Nipika at 11:20 AM (MDT) to take some rest, knowing that we would have to go back on site tonight for another night shift, to catch the 15 mm of total rain forecasted by the model GEM for the next 24 hours. After a whole night spent to get only 1 mm of rain or so, hopefully the weather will finally give us the dose of storm we are waiting for.
Team Nipika’s day started with the arrival of Cécile and Selina at noon (1800 UTC). Their arrival was greeted with light precipitation that continued for the duration of their shift. There were a wide variety of clouds, but the wind was but a whisper throughout the day. The usually rambunctious ground squirrels crawled along slowly beneath the gentle, but constant onslaught of precipitation. Meanwhile, the observers hid beneath a well-orchestrated tarp. Towards the end of the afternoon the precipitation grew a little more exciting, with a precipitation intensity of about 3 as we drove the truck out to Nipika Resort to meet up with Hadleigh and André at 1645 (2245 UTC). After this period, rainfall continued to be steady and light to moderate until it stopped quite sharply at 2130 MDT. During this event we were able to see some very interesting results from our Parsivel and Micro Rain Radar. Overall, Team Nipika received about 8 mm of precipitation throughout the day.

- Selina and André 

Field Participants: Cécile Carton, André Bertoncini, Hadleigh Thompson & Selina Mitchell

FORTRESS

May 16 & 17 (MDT) 

During our SPADE meeting on May 16 at 6 PM MDT, I discussed the GEM 2.5 model updates, however I (Juris) completely disregarded the radar and what was approaching. Thankfully, Stephen mentioned that precipitation was occurring to the South of our station and making its way north. We split into teams and made our way to Fortress as quickly as we could.

We (Hilary & Juris) arrived at Fortress by 0120 UTC on May 17 and began observations at 0130 UTC. We were curious about what the direction of the wind would be at top, given that the radar was showing a southerly flow. We weren’t surprised when we arrived on site to find that the winds were generally coming from the NW, which is more than often the case. We had mixed precipitation at the top at 0130, which transitioned to solid precipitation by 0200 UTC.

At 0340 UTC visibility became quite poor due to heavy fog and, finally, the switch in wind direction occurred that we were hoping for - some southerly to southeasterly winds! There was an organized heavier precipitation band (2-4 mm/h) situated along the foothills of the Rockies. There were moments of large aggregates and at 0405 UTC the parsivel measured aggregates up to 1.3 cm in diameter. By 0430 UTC, 1.5 cm of snow was measured on the snow depth board with a SWE of 1.5 mm.

Around 0420 UTC particles became much smaller and were often bouncing off the velvet pad. It remained very foggy with different types of precipitation, such as needles and rimed irregulars. Later in the evening at 0610 UTC, needles were observed and shortly after, at 0613 UTC, it transitioned to graupel. Pictures became easier to take as temperatures cooled off around 0840 and dipped below 0C.

-Juris

Early morning May 17 (MDT)

Aurélie & I (Charlie) left from BGI just before 0900 UTC but took a bit more time than usual to get to the site. The road was particularly foggy and we did a car sonde as soon as we observed the transition of rain to snow in Fortress Mountain. We experimented with our first night shift doing our observations in the dark. The snowfall intensity was pretty light almost all of our part of the event, except for a short peak of moderate snow around 1130 UTC. We observed mostly small hydrometeors, more precisely some beautiful fernlike dendrites, some rimed dendrites and a lot of needles! The weather conditions were stable; the temperature was between -2 and 1 degrees, the wind was very light from north and the visibility stayed very reduced. It was interesting to observe another event with north winds measured at the station even if Strathmore radar was showing cells coming from South.

-Charlie

Afternoon May 17 (MDT)

When Hilary and I (Juris) first arrived at 1811 UTC, precipitation was light and it appeared as though precipitation was making its way eastward across the foothills of the Rockies. Snow intensity was heavier (4) with aggregates of dendrites and stand alone needles. Blanketed precipitation occurred across all the continental divide.

However, it was noticeable that although the radar was showing light blue across the continental divide, the Kananaskis valley down Hwy 40 often showed no precipitation according to the radar (screenshot). This continued on, whereby the Kananaskis valley was evidently clearing, while the Columbia valley was blanketed in stratiform precipitation.

Temperatures starting at 1904 UTC on May 17 were hovering around 0°C +/- 0.2°C until May 18 at 0047 UTC. These temperatures made it hard to take photos. It was especially noticeable when temperatures climbed slightly above 0°C because the particles melted too quickly on the velvet pad, whereas when temperatures were just below 0°C, we found that it was possible to take pictures. Particles became large aggregates around 0210 UTC on May 18 and we were able to take some really beautiful pictures for about half an hour (maybe even our best photos yet!). The snow ended suddenly around 0250 UTC and we took our last observation at 0300 UTC and headed home. 

-Juris

Field Participants: Hilary Smith, Juris Almonte, Charlie Hébert-Pinard & Aurélie Desroches Lapointe

NIPIKA

Liquid Precipitation

Hadleigh, Selina, André & I (Cécile) arrived at Nipika at 10:46 PM (MDT). After a quick check-up of the instruments, which were functioning well, we organized ourselves in regard of the long night of observations we were about to live.

André and Hadleigh took the first shift until 0900 UTC. They didn't see anything other than a small drizzle and at most a light rainfall which didn't last more than a few minutes. But when Selina and I took over the observations, we noticed around 0940 UTC rainfall that lasted for about one hour, and got stronger, until reaching its maximum around 1000 UTC. It had bigger droplets and a medium falling speed, which is probably a first since we started taking observations at this site 3 weeks ago.

After that episode and for the rest of the night, drizzle and light to very light rainfall were back again. The wind was almost nonexistant during our shift, and we reached a minimum temperature of 7°C, which was actually pretty bearable for a whole night outdoors.

We left Nipika at 1720 UTC to take some rest, knowing that we would have to go back on site tonight for another night shift, to catch the 15 mm of total rain forecasted by the model GEM for the next 24 hours. After a whole night spent to get only 1 mm of rain or so, hopefully the weather will finally give us the dose of storm we are waiting for.

- Cécile

Field Participants: Hadleigh Thompson, Selina Mitchell, André Bertoncini & Cécile Carton

FORTRESS

Mixed Precipitation

Juris and I (Hilary) left BGI for Fortress shortly after 0400 UTC on May 16. We noticed some radiation fog near the ground on the way over and temperatures were above 0C. We arrived at the Fortress gate around 0435 UTC. We thought there was a possibility that precipitation could be mixed at the top, so we conducted a carsonde on the road up. Precipitation was liquid throughout the drive and we were disappointed that it was not an interesting car sonde. However, just before the parking area at the top of Fortress we noticed mixed precipitation! We took note of the altitude and time, then parked the car and finished the sonde.
 
We started taking observations at 0500 UTC. Precipitation began as mixed and very light, then became solid as the night progressed. Winds were light and pretty heavy fog rolled into the area for about half an hour around 0510 UTC. Precipitation was mostly liquid until 0930 UTC when it became solid, which consisted of mainly rimed dendrites and aggregates. From 1110 UTC precipitation consisted of small particles, but were noticeably 3D in structure, with some riming. For example, a radiating assemblage of plates was observed at 1150 UTC, although not photographed.
 
The importance of orography was also noted when winds were generally observed from the NNW, while the flow as it appeared on Strathmore radar was very different, showing a predominantly southerly flow.  
 
We (Hilary & Juris) left Fortress Mountain around 1220 UTC and conducted another carsonde heading down as Aurélie and Charlie mentioned they observed a transition from rain to snow heading up the road to replace us. At the top we had solid precipitation at 2076 m with temperatures near 0-1°C, mixed precipitation at an elevation of 1922 m with a temperature of 0.5°C. Mixed precipitation became rain at 1823 m with temperatures at ~1.6°C

-Hilary & Juris

Aurélie and I (Charlie) arrived on site at 1200 UTC for the second half of the event. It was already light to moderate snow at the top and a rain to snow transition has been observed on the way up the mountain. Between 1500 and 1630 UTC, we observed some transitions of different precipitation types, starting with capped columns, followed by unrimed dendrites, then aggregates, then rimed particles and needles, ending with graupels and a large amount of needles. Even with those important hydrometeor type changes, the weather conditions stayed pretty consistent during all of our part of this event. The wind was negligible, temperature was a bit over zero, the visibility was moderate to poor and the snow fall intensity was always light to moderate.

We notice that the Strathmore Radar was indicating no precipitation at Fortress at 1620 UTC and even after that time, it seemed like nothing was coming, new cells were appearing at the border. Although we did not observe any interruption of precipitation from 1200 UTC to our departure at 1930 UTC.

-Charlie

Field Participants: Charlie Hébert-Pinard, Aurélie Desroches Lapointe, Juris Almonte & Hilary Smith

NIPIKA
​
Cloud clears over the course of the morning

Hadleigh and André arrived at Nipika at 1130 UTC, after negotiating the forestry road and the early start of logging trucks on Settlers road. No precipitation was observed aside from two 1 minute episodes of exceptionally light drizzle. It appeared that precipitation was possibly falling onto the surrounding hills but resulting in virga above the Nipika site in the bottom of the valley.

The highlight of the morning was observing the clearing of the high cloud to the west and bright blue of the morning sky. 

-Andr​é
​
Field Participants: Hadleigh Thompson & André Bertoncini

FORTRESS
​
No precipitation 

Aurélie & Charlie headed out to Fortress to be on site for 1130 UTC as suggested by Hilary and Juris. No precipitation was observed for the entire duration at Fortress, and they left at 1500 UTC to head to Fortress Junction Service (FJS) to download data. 

The Strathmore radar shed some light on the importance of orography. From 1330 UTC to 1440, it appeared that the continental divide acted as a barrier for systems to move over to the eastern side, whereby the radar did not detect any precipitation on the eastern side of the divide near Fortress Mountain. Perhaps it was moving eastward, but was drying and warming as it moved down the leeside of the divide. The lack of precipitation was a bit disappointing, however very neat to see how important orographic features are to localized precipitation. 

Hilary and Juris had the pleasure of showing Lynn Martel, a mountain writer focused on stories of people in the mountains, around our Fortress field sites. The three of us intercepted Aurélie and Charlie at FJS and we took turns explaining the various instruments used to understand precipitation events. We also discussed what we do as field researchers and explained how our project was a comparative study between two major areas; at Nipika Mountain Resort on the western side and Fortress area on the eastern side. 

Aurélie and Charlie headed back to BGI after a long morning, while Hilary, Lynn and Juris drove up Fortress Mountain to give Lynn a tour of our trailer setup, macrophotography setup, and the rest of the instruments used for SPADE. Sun was shining with cumulus clouds overhead. Around 1800 UTC, the three women headed down the mountain and returned to BGI. 

​-Juris

Field Participants: Aurélie Desroches-Lapointe, Charlie Hébert-Pinard, Juris Almonte & Hilary Smith

Thank you to Lynn for joining us in the field and for taking an interest in our field project and for writing an article on SPADE on the Rocky Mountain Outlook. Stay tuned!

For more information on Lynn Martel and her projects check out: http://lynnmartel.ca/