The station today
Three miles from the Bay and eight from the crest of the Santa Cruz Mountains. The Bay is close enough to moderate the temperature. The Santa Cruz Mountains stand between Palo Alto and the Pacific, holding back most of the marine layer and fog and wringing out much of the rain before it arrives. So the summers are mild and dry, the fog is lighter than on the coast, and the rain is far less than the ridge gets.
The Instruments
This machine
- Signal quality
- 100%
- Transmitter battery
- OK
- Console battery
- 3.9 V
- Host
- charlemagne5t
- Operating system
- Linux 6.18.39+rpt-rpi-2712
- Server uptime
- 24 d 2 h 53 m
- WeeWX uptime
- 13 m
- VM size
- —
- VM RSS
- —
- Shared
- Data
- —
- WeeWX
- 5.5.0
- Skyfield
- 1.55
- Python
- 3.13.5
- Skin
- Tempestas 1.11.3
Credits
Data we are given
- ForecastsNWS
- KMUX radarNWS
- GOES-18 / WestNOAA
- Tide harmonicsNational Ocean Service
- EphemerisJet Propulsion Laboratory
- Star catalogESA Hipparcos
- Star namesIAU WGSN
- Twilight definitionsUSNO
The software underneath
Art and marks
Written here
All but the skin are published WeeWX extensions anyone can install. Each was written for this station to be its first user, and being used here every day is why they work.
PurpleAir readings carry the EPA correction and the 2024 EPA AQI update.
Where these observations go
The photographic recordnewest first · click any photograph to enlarge
The rooftop today
The computer rack today
Tempestas is born
LiveSeasons, the skin behind the site, is completely rewritten and renamed Tempestas, Latin for weather and season.
Carbon dioxide reporting goes live
AirGradient Open Air
Also tracking TVOC and NOx.
Weather station returned to the rooftop
The primary station and the TB3 rain gauge went back up. The secondary Vantage Pro2 and the TB7 did not.
Rooftop construction
Foam roof and solar array
Solar supports in and the deck stripped on April 10.
Foam sprayed April 23. Panels up May 1.
Construction shows up in the data
UV, solar radiation and wind speed/direction affected
The station spent six weeks off the roof. Its UV, solar radiation and wind readings for that period are compromised.
Bulky Davis consoles replaced by Envoys
Servers move to Raspberry Pi 5
A mix of NUC 7i5 and older Raspberry Pi servers becomes Raspberry Pi 5 8 GB throughout. Web traffic is served from a Google Compute Engine instance.
PurpleAir Flex installed
PurpleAir PA-II-Flex
Retired May 25, 2024
The rooftop before the foam roof and solar
Primary station at right, secondary in the background, TB3 in the foreground and the TB7 behind it.
HyQuest TB7 backup rain gauge installed
Off the roof April 10, 2025 — still on site, not operational
Second Davis Vantage Pro2 Plus installed
Davis Vantage Pro2 Plus 6163
Designated primary September 18, 2022
The station reading on this site today.
HyQuest TB3 rain gauge installed
An integrated siphon holds the calibration across a wide range of rainfall intensity. The gauge behind the rain numbers today.
RainWise industrial rain gauge installed
An eight-and-a-half-inch collector.
Retired November 24, 2022
RainWise rain gauge installed
An eight-inch collector, to the NWS specification for statistical accuracy. In service seven weeks.
Retired November 23, 2020
Davis air quality sensor installed
Davis AirLink
Evaluated alongside the PurpleAir rather than replacing it.
Retired February 15, 2023
Second weather station installed
Davis Vantage Pro2 Plus 6163
Primary September 5, 2020 · secondary September 18, 2022
Installed for testing, primary four days later. UV and solar radiation enter the record here.
Off the roof April 10, 2025 — still on site, not operational
Air quality reporting goes live
PurpleAir PA-II-SD
Two laser particle counters in one housing, each checking the other. The PA-II-SD, the Classic and the Classic Plus are successive revisions of the same sensor, so PurpleAir monitoring here has been continuous from this date.
Seismograph upgraded
Raspberry Shake 3D — R24AE, AM network
Still the instrument behind the Seismograph tab today.
Infrasound monitor goes live
Raspberry Boom — RE991, AM network
Measures sound frequencies below 20 Hz, which is below the limit of human hearing, and minute shifts in air pressure, measured in pascals (Pa), through a precision microbarometer.
Retired November 24, 2022
Seismograph goes live
Raspberry Shake 4D — R3C71, AM network
Four channels — one geophone and a three-axis accelerometer.
Recording until it was retired, May 27, 2024
PaloAltoWeather.com goes live
A vanilla install of the WeeWX weather software package with its unmodified Seasons skin.
Reporting to the National Weather Service begins
Station F4751, APRSWXNET/CWOP
From this day the station is part of the national observation network, not just a private record.
See this station on weather.gov
RainWise weather station installed
RainWise Mark III-LR
The instrument the whole record starts with. Everything measured here before September 2020 came from this station.
Retired September 18, 2022
Thumbnails until you ask for one. The full-size photograph is fetched when you open it, and not before.