diff --git a/docs/networking.md b/docs/networking.md
index c9a98d5012..e5403ca4ff 100644
--- a/docs/networking.md
+++ b/docs/networking.md
@@ -125,6 +125,20 @@ spec:
 
 Note that it is possible to break the cluster networking if flags are improperly used and as such this option should be used with caution.
 
+### Configuring Weave NPC EXTRA_ARGS
+
+Weave-npc (the Weave network policy controller) allows you to customize arguments of the running binary by setting the EXTRA_ARGS environmental variable.
+This can be used for debugging or for customizing the logging level of weave npc.
+
+```
+spec:
+  networking:
+    weave:
+      npcExtraArgs: "--log-level=info"
+```
+
+Note that it is possible to break the cluster networking if flags are improperly used and as such this option should be used with caution.
+
 ### Configuring Weave network encryption
 
 The Weave network encryption is configurable by creating a weave network secret password.
diff --git a/k8s/crds/kops.k8s.io_clusters.yaml b/k8s/crds/kops.k8s.io_clusters.yaml
index b424b598a1..268b49159f 100644
--- a/k8s/crds/kops.k8s.io_clusters.yaml
+++ b/k8s/crds/kops.k8s.io_clusters.yaml
@@ -2788,6 +2788,7 @@ spec:
                       format: int32
                       type: integer
                     netExtraArgs:
+                      description: Extra arguments that are passed to weave-kube
                       type: string
                     noMasqLocal:
                       format: int32
@@ -2799,6 +2800,9 @@ spec:
                       description: NPCCPURequest CPU request of weave npc container.
                         Default 50m
                       type: string
+                    npcExtraArgs:
+                      description: Extra arguments that are passed to weave-npc
+                      type: string
                     npcMemoryLimit:
                       description: NPCMemoryLimit memory limit of weave npc container.
                         Default 200Mi
diff --git a/pkg/apis/kops/networking.go b/pkg/apis/kops/networking.go
index cbcb0be2c9..0275fd0f5e 100644
--- a/pkg/apis/kops/networking.go
+++ b/pkg/apis/kops/networking.go
@@ -67,6 +67,7 @@ type WeaveNetworkingSpec struct {
 	ConnLimit    *int32 `json:"connLimit,omitempty"`
 	NoMasqLocal  *int32 `json:"noMasqLocal,omitempty"`
 	NetExtraArgs string `json:"netExtraArgs,omitempty"`
+	NpcExtraArgs string `json:"npcExtraArgs,omitempty"`
 
 	// MemoryRequest memory request of weave container. Default 200Mi
 	MemoryRequest *resource.Quantity `json:"memoryRequest,omitempty"`
diff --git a/pkg/apis/kops/v1alpha1/networking.go b/pkg/apis/kops/v1alpha1/networking.go
index 2ba5d5ee8b..659c0ec7c6 100644
--- a/pkg/apis/kops/v1alpha1/networking.go
+++ b/pkg/apis/kops/v1alpha1/networking.go
@@ -67,6 +67,7 @@ type WeaveNetworkingSpec struct {
 	ConnLimit    *int32 `json:"connLimit,omitempty"`
 	NoMasqLocal  *int32 `json:"noMasqLocal,omitempty"`
 	NetExtraArgs string `json:"netExtraArgs,omitempty"`
+	NpcExtraArgs string `json:"npcExtraArgs,omitempty"`
 
 	// MemoryRequest memory request of weave container. Default 200Mi
 	MemoryRequest *resource.Quantity `json:"memoryRequest,omitempty"`
diff --git a/pkg/apis/kops/v1alpha1/zz_generated.conversion.go b/pkg/apis/kops/v1alpha1/zz_generated.conversion.go
index 46c0b4dd3e..556bbac2bc 100644
--- a/pkg/apis/kops/v1alpha1/zz_generated.conversion.go
+++ b/pkg/apis/kops/v1alpha1/zz_generated.conversion.go
@@ -4853,6 +4853,7 @@ func autoConvert_v1alpha1_WeaveNetworkingSpec_To_kops_WeaveNetworkingSpec(in *We
 	out.ConnLimit = in.ConnLimit
 	out.NoMasqLocal = in.NoMasqLocal
 	out.NetExtraArgs = in.NetExtraArgs
+	out.NpcExtraArgs = in.NpcExtraArgs
 	out.MemoryRequest = in.MemoryRequest
 	out.CPURequest = in.CPURequest
 	out.MemoryLimit = in.MemoryLimit
@@ -4874,6 +4875,7 @@ func autoConvert_kops_WeaveNetworkingSpec_To_v1alpha1_WeaveNetworkingSpec(in *ko
 	out.ConnLimit = in.ConnLimit
 	out.NoMasqLocal = in.NoMasqLocal
 	out.NetExtraArgs = in.NetExtraArgs
+	out.NpcExtraArgs = in.NpcExtraArgs
 	out.MemoryRequest = in.MemoryRequest
 	out.CPURequest = in.CPURequest
 	out.MemoryLimit = in.MemoryLimit
diff --git a/pkg/apis/kops/v1alpha2/networking.go b/pkg/apis/kops/v1alpha2/networking.go
index e607676a01..d7e300f3d4 100644
--- a/pkg/apis/kops/v1alpha2/networking.go
+++ b/pkg/apis/kops/v1alpha2/networking.go
@@ -67,6 +67,7 @@ type WeaveNetworkingSpec struct {
 	ConnLimit    *int32 `json:"connLimit,omitempty"`
 	NoMasqLocal  *int32 `json:"noMasqLocal,omitempty"`
 	NetExtraArgs string `json:"netExtraArgs,omitempty"`
+	NpcExtraArgs string `json:"npcExtraArgs,omitempty"`
 
 	// MemoryRequest memory request of weave container. Default 200Mi
 	MemoryRequest *resource.Quantity `json:"memoryRequest,omitempty"`
diff --git a/pkg/apis/kops/v1alpha2/zz_generated.conversion.go b/pkg/apis/kops/v1alpha2/zz_generated.conversion.go
index 06041c4bb1..f6f3ca575a 100644
--- a/pkg/apis/kops/v1alpha2/zz_generated.conversion.go
+++ b/pkg/apis/kops/v1alpha2/zz_generated.conversion.go
@@ -5181,6 +5181,7 @@ func autoConvert_v1alpha2_WeaveNetworkingSpec_To_kops_WeaveNetworkingSpec(in *We
 	out.ConnLimit = in.ConnLimit
 	out.NoMasqLocal = in.NoMasqLocal
 	out.NetExtraArgs = in.NetExtraArgs
+	out.NpcExtraArgs = in.NpcExtraArgs
 	out.MemoryRequest = in.MemoryRequest
 	out.CPURequest = in.CPURequest
 	out.MemoryLimit = in.MemoryLimit
@@ -5202,6 +5203,7 @@ func autoConvert_kops_WeaveNetworkingSpec_To_v1alpha2_WeaveNetworkingSpec(in *ko
 	out.ConnLimit = in.ConnLimit
 	out.NoMasqLocal = in.NoMasqLocal
 	out.NetExtraArgs = in.NetExtraArgs
+	out.NpcExtraArgs = in.NpcExtraArgs
 	out.MemoryRequest = in.MemoryRequest
 	out.CPURequest = in.CPURequest
 	out.MemoryLimit = in.MemoryLimit
diff --git a/upup/models/cloudup/resources/addons/networking.weave/k8s-1.12.yaml.template b/upup/models/cloudup/resources/addons/networking.weave/k8s-1.12.yaml.template
index e00ef788c5..3b4b0b3db8 100644
--- a/upup/models/cloudup/resources/addons/networking.weave/k8s-1.12.yaml.template
+++ b/upup/models/cloudup/resources/addons/networking.weave/k8s-1.12.yaml.template
@@ -211,6 +211,10 @@ spec:
                 fieldRef:
                   apiVersion: v1
                   fieldPath: spec.nodeName
+            {{- if .Networking.Weave.NpcExtraArgs }}
+            - name: EXTRA_ARGS
+              value: "{{ .Networking.Weave.NpcExtraArgs }}"
+            {{- end }}
           image: 'weaveworks/weave-npc:2.6.0'
           ports:
             - name: metrics
diff --git a/upup/models/cloudup/resources/addons/networking.weave/k8s-1.7.yaml.template b/upup/models/cloudup/resources/addons/networking.weave/k8s-1.7.yaml.template
index b55341ffa4..152fd0c67c 100644
--- a/upup/models/cloudup/resources/addons/networking.weave/k8s-1.7.yaml.template
+++ b/upup/models/cloudup/resources/addons/networking.weave/k8s-1.7.yaml.template
@@ -203,6 +203,10 @@ spec:
                 fieldRef:
                   apiVersion: v1
                   fieldPath: spec.nodeName
+            {{- if .Networking.Weave.NpcExtraArgs }}
+            - name: EXTRA_ARGS
+              value: "{{ .Networking.Weave.NpcExtraArgs }}"
+            {{- end }}
           image: 'weaveworks/weave-npc:2.6.0'
           ports:
             - name: metrics
diff --git a/upup/models/cloudup/resources/addons/networking.weave/k8s-1.8.yaml.template b/upup/models/cloudup/resources/addons/networking.weave/k8s-1.8.yaml.template
index cd83d8d026..d5113340a7 100644
--- a/upup/models/cloudup/resources/addons/networking.weave/k8s-1.8.yaml.template
+++ b/upup/models/cloudup/resources/addons/networking.weave/k8s-1.8.yaml.template
@@ -207,6 +207,10 @@ spec:
                 fieldRef:
                   apiVersion: v1
                   fieldPath: spec.nodeName
+            {{- if .Networking.Weave.NpcExtraArgs }}
+            - name: EXTRA_ARGS
+              value: "{{ .Networking.Weave.NpcExtraArgs }}"
+            {{- end }}
           image: 'weaveworks/weave-npc:2.6.0'
           ports:
             - name: metrics