Testing the Rain Sensor

I woke up on October 6th (Lisbon, Portugal) to find my balcony totally wet from the rain. The top of my Tempest was covered in big raindrops… BUT…

i) I received no rain alerts
ii) In the app history, no rain accumulation was shown.
iii) I’ve done a check of the data using the REST API. The observations do not show any accumulation or precipitation events (items 12 and 13 in the list below).

Tempest (type=“obs_st”)
Observation Layout
0 - Epoch (Seconds UTC)
1 - Wind Lull (m/s)
2 - Wind Avg (m/s)
3 - Wind Gust (m/s)
4 - Wind Direction (degrees)
5 - Wind Sample Interval (seconds)
6 - Pressure (MB)
7 - Air Temperature ©
8 - Relative Humidity (%)
9 - Illuminance (lux)
10 - UV (index)
11 - Solar Radiation (W/m^2)
12 - Rain Accumulation (mm)
13 - Precipitation Type (0 = none, 1 = rain, 2 = hail)
14 - Average Strike Distance (km)
15 - Strike Count
16 - Battery (volts)
17 - Report Interval (minutes)
18 - Local Day Rain Accumulation (mm)
19 - Rain Accumulation Final (Rain Check) (mm)
20 - Local Day Rain Accumulation Final (Rain Check) (mm)
21 - Precipitation Aanalysis Type (0 = none, 1 = Rain Check with user display on, 2 = Rain Check with user display off)

Today, October 7th, I tested the sensor by (i) pouring water on the Tempest using a cup and (ii) tapping my fingers on the top of the Tempest.

As I did these, I was running a program that captured the UDP messages from the HUB.

I’m happy to report that both the pouring of water and tapping of fingers were detected - I checked UDP messages from the hub and also did some calls via the REST API.

By the way, the tapping of fingers was detected as hail…

Ok, so far so good…

The part that is sucky…
i) only some rain events are reported via alerts in the app… or maybe not all alerts/notifications are sent or received.

ii) Watching the UDP data from the hub, if I start pouring water or tapping my fingers, a message is not sent out immediately… The “rain” event is only sent out with the rest of the observation data - sent once a minute… By the time the message reaches the app, 2 minutes or more may have gone by… not really useful for any home automation or real-time action… Will do more investigation to make sure I’m not missing something…

So, when you pour water on it, or tap with your finger, you are NOT seeing the ‘evt_precip’ message on UDP?

	  "serial_number": "SK-00008453",
	  "hub_sn": "HB-00000001",


This is think is standard behaviour to stop notification spamming. If the rain is stopping and starting with a few minutes between each “event”, you won’t get a new notification for every time it starts raining. There is some timeout that must elapse before a new rain notification is triggered.

This is not normal. You should get the evt_precip message as indicated by @btst.online

Hi Sam,
I’ve done the finger-tapping, water-pouring test about 20 times. I’ve only ever seen the “evt_precip” message once.

I’m attaching a capture (UDP) where I did the following:
i) started running the capture program
ii) waited for a msg of type “obs_st”… see line/msg 10. You can see that “Precip Accumulated” is 0.000000 and “Precipitation Type” is 0 (0==none).
iii) waited about 30 seconds before I started pouring water from a cup. Poured for over 5 seconds.
iv) waited to receive another “obs_st” msg. see line/msg 50. You can see that “Precip Accumulated” is 0.405694 and “Precipitation Type” is 1 (1==rain).

Notice that there is no “evt_precip” message in-between the two “obs_st” messages.

haptic_sensor_test_20201007_udp_capture.txt (6.7 KB)

Yeah, definitely not normal.
@WFstaff, @dsj needs to weigh in on why you are not getting the evt_precip message…

Hi johnny. The evt_precip (aka “rain start”) message is only fired if no rain has been detected in the past 15 minutes. You can also cycle the power on the Tempest to reset that. Please make sure either of those events occurs before running your test and if you still don’t see the evt_precip message, something’s definitely fishy.

PS: Light finger taps will probably work better than pouring water - a steady stream of water may not be detected as rain

PPS: Also keep in mind that UDP is a “best effort” protocol and messages can get dropped on busy Wi-Fi networks (I know you said you tried it 20 times so that’s probably not the issue)

PPPS: I moved this to #developers since it’s not a normal “owner” use case :slight_smile:


I think that may be exactly what’s happening!!.. I will test again and give an update… in the #developers section.

I really appreciate the great support


I didn’t know that. I thought the timeout was an app level behaviour rather than a hub level behaviour. Good to know!