highcharts - add label by custom id - highcharts

Question

I have a sparkline chart of temperature sensor data,
Its a year of data sampled at every 1 min
I first load a blank chart, then I do a server call, bring the results back and display it by calling
getchart.addSeries({
name: thisGroup,
id: probeItem[0],
data: probeDataArray,
keys: ['x', 'y', 'specialId'],
there could be upto 20 series, and they all load on the screen one by one
This renders quite quickly, however I now need to add a label annotation where the temperature goes over a certain Value (i.e. in add a warning symbol when its alarm state)
Currently I'm looping through each point and seeing if its over a certain value:
currentSeries.points.forEach(function (point) {
However this is very slow.
I have an array of the alarms, and can reference them as
['x', 'y', 'specialId']
However I cannot see how I can add an annotation label by x,y or specialId.
I can only seem to add the label if i loop through all the points already rendered
Is there a way to add a label by using my Id's?
I also need to resize the graph and the labels to remain in the same place
Alternatively if this is not possible, is there anyway to add the labels as i'm adding the series?:
getchart.addSeries({
name: thisGroup,
id: CurrentGroupID,
dashStyle: 'ShortDot',
data: groupLogArray,
keys: ['x', 'y', 'specialId'],
showInNavigator: true, //this shows the series data in the small bottom navigator
point: {
events: {
click: function () {
//alert("test click");
}
}
}
});

Answer 1

You can add an annotation by x and y axis values:
chart.addAnnotation({
labels: [{
text: 'Alarm',
point: {
x: 2,
y: 3,
xAxis: 0,
yAxis: 0
}
}]
});
Live demo: http://jsfiddle.net/BlackLabel/k6trha3e/
API Reference: https://api.highcharts.com/class-reference/Highcharts.Chart#addAnnotation
As an alternative, you can also use data labels: http://jsfiddle.net/BlackLabel/n4586xzq/