The station is based on an ESP-01 WiFi module connected to a BME280 (air pressure, humidity and temperature) and a MAX44009 (light) sensor module using the I2C bus. It operates in deep sleep mode to conserve power and transmits its data over the WIFI at 15 minute wake up intervals. It runs on one 18650 rechargeable battery via a MCP1700 3.3V regulator as the ESP-01 has a maximum recommended voltage of 3.3V.
The software now alerts by email when battery voltage starts to drop.
Note – temperature recording is highly inaccurate during daytime. The case for the station has a perspex cover. When the sun comes out it becomes a mini-greenhouse.


Battery voltage = 3.4 V
Last read – 2021-11-30 09:51:28
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Pressure Temperature Humidity Light Intensity
1003.4 mb 4.6 °C 92.4 % 1273.0 lux
Data graphed for last 24 hours
Data graphed for last 28 days
Raw data for the past 24 hours.

Pressure (mb) Temperature (°C) Humidity (%) Light (lux) Date/Time
1007.1 0.3 89.1 2154.2 2021-11-29 10:15:37
1006.9 0.3 88.8 1468.8 2021-11-29 10:29:55
1006.7 0.7 88.6 2350.1 2021-11-29 10:44:14
1006.1 1.6 87.2 3133.4 2021-11-29 10:58:34
1005.8 2.1 85.6 5483.5 2021-11-29 11:12:51
1005.7 2.0 85.0 3133.4 2021-11-29 11:27:10
1005.4 3.3 85.1 3916.8 2021-11-29 11:41:31
1005.0 3.7 84.7 4308.5 2021-11-29 11:55:50
1004.8 3.9 84.3 6266.9 2021-11-29 12:10:08
1004.5 4.8 82.9 6266.9 2021-11-29 12:24:28
1004.3 5.4 81.6 5091.8 2021-11-29 12:38:49
1004.1 4.8 83.0 3525.1 2021-11-29 12:53:05
1004.0 5.2 83.4 4308.5 2021-11-29 13:07:24
1003.9 5.6 84.3 3133.4 2021-11-29 13:21:43
1003.8 5.6 85.5 3133.4 2021-11-29 13:36:02
1003.6 5.9 86.6 2937.6 2021-11-29 13:50:21
1003.6 5.8 87.9 2154.2 2021-11-29 14:04:38
1003.4 6.1 89.1 1762.6 2021-11-29 14:18:57
1003.6 6.0 90.0 979.2 2021-11-29 14:33:15
1003.7 6.1 90.8 1273.0 2021-11-29 14:47:33
1003.5 5.9 91.0 1077.1 2021-11-29 15:01:50
1003.7 6.1 91.7 587.5 2021-11-29 15:16:09
1003.8 6.0 92.0 342.7 2021-11-29 15:30:28
1004.0 6.3 92.4 146.9 2021-11-29 15:44:46
1004.3 6.0 92.6 45.9 2021-11-29 15:59:04
1004.8 6.1 92.8 5.4 2021-11-29 16:13:21
1004.5 6.5 93.0 0.8 2021-11-29 16:27:42
1004.7 6.2 93.0 0.0 2021-11-29 16:41:59
1005.0 6.1 93.1 0.0 2021-11-29 16:56:16
1005.1 5.7 92.9 0.0 2021-11-29 17:10:33
1005.3 5.6 92.9 0.0 2021-11-29 17:24:51
1005.3 5.4 92.9 0.0 2021-11-29 17:39:09
1005.6 5.1 92.8 0.0 2021-11-29 17:53:27
1005.7 5.2 92.8 0.0 2021-11-29 18:07:45
1005.8 4.8 92.7 0.0 2021-11-29 18:22:03
1005.9 5.1 92.9 0.0 2021-11-29 18:36:20
1005.9 4.9 92.8 0.0 2021-11-29 18:50:38
1006.1 4.1 92.4 0.0 2021-11-29 19:04:54
1006.3 3.2 91.9 0.0 2021-11-29 19:19:11
1006.2 3.1 92.2 0.0 2021-11-29 19:33:29
1006.4 2.8 92.1 0.0 2021-11-29 19:47:46
1006.5 3.0 92.2 0.0 2021-11-29 20:02:03
1006.4 3.8 92.6 0.0 2021-11-29 20:16:22
1006.3 3.9 92.6 0.0 2021-11-29 20:30:41
1006.5 3.4 92.3 0.0 2021-11-29 20:44:58
1006.7 3.3 92.3 0.0 2021-11-29 20:59:15
1006.8 3.7 92.5 0.0 2021-11-29 21:13:33
1006.9 3.7 92.5 0.0 2021-11-29 21:27:51
1007.0 3.9 92.5 0.0 2021-11-29 21:42:10
1007.0 4.0 92.5 0.0 2021-11-29 21:56:28
1006.9 3.9 92.5 0.0 2021-11-29 22:10:45
1007.2 3.9 92.5 0.0 2021-11-29 22:25:05
1007.2 4.2 92.5 0.0 2021-11-29 22:39:23
1007.3 4.2 92.6 0.0 2021-11-29 22:53:42
1007.5 3.9 92.5 0.0 2021-11-29 23:07:59
1007.6 4.1 92.6 0.0 2021-11-29 23:22:18
1007.5 4.1 92.6 0.0 2021-11-29 23:36:36
1007.4 4.1 92.7 0.0 2021-11-29 23:50:54
1007.6 4.0 92.7 0.0 2021-11-30 00:05:12
1007.9 3.9 92.7 0.0 2021-11-30 00:19:30
1008.0 3.7 92.6 0.0 2021-11-30 00:33:47
1008.1 3.6 92.6 0.0 2021-11-30 00:48:05
1007.9 3.4 92.6 0.0 2021-11-30 01:02:22
1008.0 3.2 92.5 0.0 2021-11-30 01:16:39
1007.7 3.2 92.5 0.0 2021-11-30 01:30:57
1007.6 3.2 92.5 0.0 2021-11-30 01:45:15
1007.7 3.1 92.5 0.0 2021-11-30 01:59:32
1007.7 3.1 92.5 0.0 2021-11-30 02:13:50
1007.5 3.2 92.6 0.0 2021-11-30 02:28:08
1007.4 3.2 92.6 0.0 2021-11-30 02:42:26
1007.3 3.2 92.6 0.0 2021-11-30 02:56:44
1007.1 3.2 92.6 0.0 2021-11-30 03:11:02
1007.0 3.2 92.6 0.0 2021-11-30 03:25:20
1006.9 3.1 92.6 0.0 2021-11-30 03:39:37
1006.8 3.0 92.6 0.0 2021-11-30 03:53:55
1006.6 3.0 92.5 0.0 2021-11-30 04:08:12
1006.6 3.0 92.5 0.0 2021-11-30 04:22:29
1006.3 3.0 92.6 0.0 2021-11-30 04:36:47
1006.1 3.0 92.6 0.0 2021-11-30 04:51:05
1005.9 3.0 92.6 0.0 2021-11-30 05:05:23
1005.8 3.1 92.6 0.0 2021-11-30 05:19:40
1005.5 3.1 92.6 0.0 2021-11-30 05:33:58
1006.3 3.2 92.6 0.0 2021-11-30 05:48:16
1006.2 3.2 92.6 0.0 2021-11-30 06:02:34
1006.1 3.0 92.6 0.0 2021-11-30 06:16:51
1006.0 3.1 92.6 0.0 2021-11-30 06:31:09
1005.9 3.0 92.6 0.0 2021-11-30 06:45:26
1005.8 3.1 92.7 0.0 2021-11-30 06:59:44
1005.6 3.1 92.7 0.0 2021-11-30 07:14:04
1005.4 3.2 92.7 0.0 2021-11-30 07:28:21
1005.2 3.3 92.7 0.0 2021-11-30 07:42:40
1005.0 3.3 92.8 2.3 2021-11-30 07:56:58
1005.0 3.4 92.8 15.3 2021-11-30 08:11:14
1004.5 3.5 92.8 73.4 2021-11-30 08:25:34
1004.5 3.5 92.8 146.9 2021-11-30 08:39:52
1004.3 3.7 92.8 367.2 2021-11-30 08:54:11
1003.9 3.9 92.7 587.5 2021-11-30 09:08:31
1003.8 4.1 92.6 685.4 2021-11-30 09:22:50
1003.7 4.3 92.6 979.2 2021-11-30 09:37:09
1003.4 4.6 92.4 1273.0 2021-11-30 09:51:28