Discussion: Saturday Middle ON - starts from 2:30pm

Saturday Middle to Take Place this Afternoon
As the air quality has improved somewhat, and may get a bit better this afternoon with slightly increased west winds, we have decided to hold the Middle event this afternoon.

Air quality is at the moment still in the range described as "everyone may begin to experience health effects if they are exposed for 24 hours." Each orienteer should make his or her own decision about whether it is safe enough to participate.

Please add 4.5 hours to your start time for the Middle, as starts will begin at 2:30 PM.

Packets will be available beginning at 1:30 PM.

The dinner at Northstar will begin at 6:00 PM today, and awards will start shortly after 7:00. Since we are pressed for time this afternoon, we have extended the schedule: you will still get freshly-made pizza if you arrive by 7:00, and food will available until 8:00. As a reminder, the dinner is outdoors.

Plan for tomorrow
A decision will be made tomorrow morning around 6:00 AM; watch for an announcement shortly after that time.

Tahoe 2021 committee

What is the "air quality index" (or even the "category") going to be during the race?

Current AQI at Prosser Dam just south of the venue is 191. It has dropped considerably from this morning, when it was just over 400. 191 is in the "Unhealthy" category (take precautions) while 400 is in the "Hazardous" category (stay inside).

Interactive map of air quality sensor data is here:

https://fire.airnow.gov/

The next sensor NW of Little Truckee Summit at Sierraville is still reading 250 "Very Unhealthy." That one is at the S end of a valley and closer to the Dixie complex.

Here's the chart of AQI (PM2.5 fine particulate matter) vs time over the past 7 days at the Prosser site just north of Truckee:



An unfortunate wind change this weekend brought it in very quickly.

Here's a link to the Pacific Northwest geocolor satellite animation - most recent 96 frames. Everything white/brown over CA, NV, and UT today is smoke.

It didn't feel too bad running out there this afternoon

I thought it was very tough on the lungs. I pretty much coughed nonstop for a half hour after finishing...

I've been coughing since waking up. Intermittently, but noticeable.

Wow, you can see the Dixie smoke plumes...

There's an AQI monitoring station on Sage Hen rd 2km SW of the Long Distance drop-off/parking area on hwy 89. Here's the chart as of 10 PM PDT this evening. Air quality has been steady at about 170 "unhealthy" since noon. So right now conditions are the same as they were today at the middle:



To check the current conditions at this monitoring site use the following link, zoom in to Truckee and find the site on Sage Hen road just north of town:

https://fire.airnow.gov/

That monitoring station was one of the control locations for the model event.