diff --git a/jsonnet/kube-prometheus/kube-prometheus.libsonnet b/jsonnet/kube-prometheus/kube-prometheus.libsonnet
index 513bba9d4eb85088bbe2f07d8ad62f2bde63bafe..71715250f0b12831fc50590725f35c00936997c5 100644
--- a/jsonnet/kube-prometheus/kube-prometheus.libsonnet
+++ b/jsonnet/kube-prometheus/kube-prometheus.libsonnet
@@ -116,6 +116,7 @@ local configMapList = k3.core.v1.configMapList;
     kubeletSelector: 'job="kubelet", metrics_path="/metrics"',
     kubeStateMetricsSelector: 'job="kube-state-metrics"',
     nodeExporterSelector: 'job="node-exporter"',
+    fsSpaceFillingUpCriticalThreshold: 15,
     notKubeDnsSelector: 'job!="kube-dns"',
     kubeSchedulerSelector: 'job="kube-scheduler"',
     kubeControllerManagerSelector: 'job="kube-controller-manager"',
diff --git a/jsonnetfile.lock.json b/jsonnetfile.lock.json
index 769db3cc138204ffecf0965a101d37884906455b..fa05ae28c854ebb66b879053c48444698b363dc8 100644
--- a/jsonnetfile.lock.json
+++ b/jsonnetfile.lock.json
@@ -105,8 +105,8 @@
           "subdir": "docs/node-mixin"
         }
       },
-      "version": "92ea3c6a3f0ea2d1d55de168e65037e2313f9940",
-      "sum": "7vEamDTP9AApeiF4Zu9ZyXzDIs3rYHzwf9k7g8X+wsg="
+      "version": "0107bc794204f50d887898da60032da890637471",
+      "sum": "VKdF0zPMSCiuIuXWblSz2VOeBaXzQ7fp40vz9sxj+Bo="
     },
     {
       "name": "prometheus",
diff --git a/manifests/prometheus-rules.yaml b/manifests/prometheus-rules.yaml
index 522433d12e76b5a5961dd5d1c0f79f368d4afa57..aababcb5991e0ad776f3f3615ed5b7f3433f4969 100644
--- a/manifests/prometheus-rules.yaml
+++ b/manifests/prometheus-rules.yaml
@@ -330,7 +330,7 @@ spec:
         summary: Filesystem is predicted to run out of space within the next 4 hours.
       expr: |
         (
-          node_filesystem_avail_bytes{job="node-exporter",fstype!=""} / node_filesystem_size_bytes{job="node-exporter",fstype!=""} * 100 < 20
+          node_filesystem_avail_bytes{job="node-exporter",fstype!=""} / node_filesystem_size_bytes{job="node-exporter",fstype!=""} * 100 < 15
         and
           predict_linear(node_filesystem_avail_bytes{job="node-exporter",fstype!=""}[6h], 4*60*60) < 0
         and