Analytics Thresholds

The monitor application uses several numeric thresholds to determine when to raise alerts and warnings. These constants are defined in src/analytics/thresholds.ts and can be adjusted without modifying any other file.

Threshold Constants

Constant	Default Value	Description
TEMP_OVERHEAT_C	40	Temperature in degrees Celsius above which a node is flagged as overheating.
TEMP_RAPID_CHANGE_PER_MIN	2.0	Rate of temperature change in degrees Celsius per minute that triggers a rapid-change warning.
PRESSURE_RAPID_DROP_PER_MIN	0.5	Rate of pressure drop in hPa per minute that triggers an alert.
NODE_OFFLINE_SECONDS	60	Seconds since the last received packet before a node is considered offline.
NODE_STALE_SECONDS	30	Seconds since the last received packet before a node is considered stale (still online, but slow to report).
MIN_POINTS_FOR_TREND	3	Minimum number of data points required before a trend (rising, falling, stable) is computed.

How Thresholds Are Used

Temperature Alerts

The computeSensorInsights() function checks each temperature node’s current reading and rate of change:

• If the latest temperature exceeds TEMP_OVERHEAT_C, an overheating anomaly flag is raised.
• If the rate of temperature change exceeds TEMP_RAPID_CHANGE_PER_MIN, a rapid change warning is raised.

Pressure Alerts

• If the rate of pressure decrease exceeds PRESSURE_RAPID_DROP_PER_MIN, a rapid pressure drop alert is raised. Rapid pressure drops can indicate approaching severe weather.

Node Health

The computeNodeHealth() function uses the time thresholds:

• If a node has not been heard for longer than NODE_STALE_SECONDS, it is marked as stale (amber warning).
• If a node has not been heard for longer than NODE_OFFLINE_SECONDS, it is marked as offline (red alert).

Trend Detection

The computeSensorInsights() function will not compute trend direction or rate of change until at least MIN_POINTS_FOR_TREND data points are available for a given sensor. This prevents misleading trends from insufficient data.

Modifying Thresholds

To change a threshold, edit src/analytics/thresholds.ts:

// Example: raise the overheat threshold to 50 degrees C
export const TEMP_OVERHEAT_C = 50;

// Example: require more data points before showing trends
export const MIN_POINTS_FOR_TREND = 5;

Changes take effect immediately in development mode (via hot reload) or after the next build.