diff --git a/java-monitoring/README.md b/java-monitoring/README.md
index 6ed7b0632ede..9e00bae6b8ee 100644
--- a/java-monitoring/README.md
+++ b/java-monitoring/README.md
@@ -195,7 +195,7 @@ Java is a registered trademark of Oracle and/or its affiliates.
 [kokoro-badge-link-5]: http://storage.googleapis.com/cloud-devrel-public/java/badges/google-cloud-java/java11.html
 [stability-image]: https://img.shields.io/badge/stability-stable-green
 [maven-version-image]: https://img.shields.io/maven-central/v/com.google.cloud/google-cloud-monitoring.svg
-[maven-version-link]: https://central.sonatype.com/artifact/com.google.cloud/google-cloud-monitoring/3.31.0
+[maven-version-link]: https://central.sonatype.com/artifact/com.google.cloud/google-cloud-monitoring/3.33.0
 [authentication]: https://github.com/googleapis/google-cloud-java#authentication
 [auth-scopes]: https://developers.google.com/identity/protocols/oauth2/scopes
 [predefined-iam-roles]: https://cloud.google.com/iam/docs/understanding-roles#predefined_roles
diff --git a/java-monitoring/google-cloud-monitoring/src/main/resources/META-INF/native-image/com.google.cloud.monitoring.v3/reflect-config.json b/java-monitoring/google-cloud-monitoring/src/main/resources/META-INF/native-image/com.google.cloud.monitoring.v3/reflect-config.json
index 5021e69939b8..8d247d01bd5d 100644
--- a/java-monitoring/google-cloud-monitoring/src/main/resources/META-INF/native-image/com.google.cloud.monitoring.v3/reflect-config.json
+++ b/java-monitoring/google-cloud-monitoring/src/main/resources/META-INF/native-image/com.google.cloud.monitoring.v3/reflect-config.json
@@ -944,6 +944,15 @@
     "allDeclaredClasses": true,
     "allPublicClasses": true
   },
+  {
+    "name": "com.google.monitoring.v3.AlertPolicy$Severity",
+    "queryAllDeclaredConstructors": true,
+    "queryAllPublicConstructors": true,
+    "queryAllDeclaredMethods": true,
+    "allPublicMethods": true,
+    "allDeclaredClasses": true,
+    "allPublicClasses": true
+  },
   {
     "name": "com.google.monitoring.v3.BasicSli",
     "queryAllDeclaredConstructors": true,
diff --git a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicy.java b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicy.java
index 75474ed83751..e790ffcf1918 100644
--- a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicy.java
+++ b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicy.java
@@ -46,6 +46,7 @@ private AlertPolicy() {
     conditions_ = java.util.Collections.emptyList();
     combiner_ = 0;
     notificationChannels_ = com.google.protobuf.LazyStringArrayList.emptyList();
+    severity_ = 0;
   }
 
   @java.lang.Override
@@ -274,6 +275,193 @@ private ConditionCombinerType(int value) {
     // @@protoc_insertion_point(enum_scope:google.monitoring.v3.AlertPolicy.ConditionCombinerType)
   }
 
+  /**
+   *
+   *
+   * <pre>
+   * An enumeration of possible severity level for an Alert Policy.
+   * </pre>
+   *
+   * Protobuf enum {@code google.monitoring.v3.AlertPolicy.Severity}
+   */
+  public enum Severity implements com.google.protobuf.ProtocolMessageEnum {
+    /**
+     *
+     *
+     * <pre>
+     * No severity is specified. This is the default value.
+     * </pre>
+     *
+     * <code>SEVERITY_UNSPECIFIED = 0;</code>
+     */
+    SEVERITY_UNSPECIFIED(0),
+    /**
+     *
+     *
+     * <pre>
+     * This is the highest severity level. Use this if the problem could
+     * cause significant damage or downtime.
+     * </pre>
+     *
+     * <code>CRITICAL = 1;</code>
+     */
+    CRITICAL(1),
+    /**
+     *
+     *
+     * <pre>
+     * This is the medium severity level. Use this if the problem could
+     * cause minor damage or downtime.
+     * </pre>
+     *
+     * <code>ERROR = 2;</code>
+     */
+    ERROR(2),
+    /**
+     *
+     *
+     * <pre>
+     * This is the lowest severity level. Use this if the problem is not causing
+     * any damage or downtime, but could potentially lead to a problem in the
+     * future.
+     * </pre>
+     *
+     * <code>WARNING = 3;</code>
+     */
+    WARNING(3),
+    UNRECOGNIZED(-1),
+    ;
+
+    /**
+     *
+     *
+     * <pre>
+     * No severity is specified. This is the default value.
+     * </pre>
+     *
+     * <code>SEVERITY_UNSPECIFIED = 0;</code>
+     */
+    public static final int SEVERITY_UNSPECIFIED_VALUE = 0;
+    /**
+     *
+     *
+     * <pre>
+     * This is the highest severity level. Use this if the problem could
+     * cause significant damage or downtime.
+     * </pre>
+     *
+     * <code>CRITICAL = 1;</code>
+     */
+    public static final int CRITICAL_VALUE = 1;
+    /**
+     *
+     *
+     * <pre>
+     * This is the medium severity level. Use this if the problem could
+     * cause minor damage or downtime.
+     * </pre>
+     *
+     * <code>ERROR = 2;</code>
+     */
+    public static final int ERROR_VALUE = 2;
+    /**
+     *
+     *
+     * <pre>
+     * This is the lowest severity level. Use this if the problem is not causing
+     * any damage or downtime, but could potentially lead to a problem in the
+     * future.
+     * </pre>
+     *
+     * <code>WARNING = 3;</code>
+     */
+    public static final int WARNING_VALUE = 3;
+
+    public final int getNumber() {
+      if (this == UNRECOGNIZED) {
+        throw new java.lang.IllegalArgumentException(
+            "Can't get the number of an unknown enum value.");
+      }
+      return value;
+    }
+
+    /**
+     * @param value The numeric wire value of the corresponding enum entry.
+     * @return The enum associated with the given numeric wire value.
+     * @deprecated Use {@link #forNumber(int)} instead.
+     */
+    @java.lang.Deprecated
+    public static Severity valueOf(int value) {
+      return forNumber(value);
+    }
+
+    /**
+     * @param value The numeric wire value of the corresponding enum entry.
+     * @return The enum associated with the given numeric wire value.
+     */
+    public static Severity forNumber(int value) {
+      switch (value) {
+        case 0:
+          return SEVERITY_UNSPECIFIED;
+        case 1:
+          return CRITICAL;
+        case 2:
+          return ERROR;
+        case 3:
+          return WARNING;
+        default:
+          return null;
+      }
+    }
+
+    public static com.google.protobuf.Internal.EnumLiteMap<Severity> internalGetValueMap() {
+      return internalValueMap;
+    }
+
+    private static final com.google.protobuf.Internal.EnumLiteMap<Severity> internalValueMap =
+        new com.google.protobuf.Internal.EnumLiteMap<Severity>() {
+          public Severity findValueByNumber(int number) {
+            return Severity.forNumber(number);
+          }
+        };
+
+    public final com.google.protobuf.Descriptors.EnumValueDescriptor getValueDescriptor() {
+      if (this == UNRECOGNIZED) {
+        throw new java.lang.IllegalStateException(
+            "Can't get the descriptor of an unrecognized enum value.");
+      }
+      return getDescriptor().getValues().get(ordinal());
+    }
+
+    public final com.google.protobuf.Descriptors.EnumDescriptor getDescriptorForType() {
+      return getDescriptor();
+    }
+
+    public static final com.google.protobuf.Descriptors.EnumDescriptor getDescriptor() {
+      return com.google.monitoring.v3.AlertPolicy.getDescriptor().getEnumTypes().get(1);
+    }
+
+    private static final Severity[] VALUES = values();
+
+    public static Severity valueOf(com.google.protobuf.Descriptors.EnumValueDescriptor desc) {
+      if (desc.getType() != getDescriptor()) {
+        throw new java.lang.IllegalArgumentException("EnumValueDescriptor is not for this type.");
+      }
+      if (desc.getIndex() == -1) {
+        return UNRECOGNIZED;
+      }
+      return VALUES[desc.getIndex()];
+    }
+
+    private final int value;
+
+    private Severity(int value) {
+      this.value = value;
+    }
+
+    // @@protoc_insertion_point(enum_scope:google.monitoring.v3.AlertPolicy.Severity)
+  }
+
   public interface DocumentationOrBuilder
       extends
       // @@protoc_insertion_point(interface_extends:google.monitoring.v3.AlertPolicy.Documentation)
@@ -3503,6 +3691,7 @@ public interface ForecastOptionsOrBuilder
          * found to violate the threshold, and the violation is observed in all
          * forecasts made for the configured `duration`, then the time series is
          * considered to be failing.
+         * The forecast horizon can range from 1 hour to 60 hours.
          * </pre>
          *
          * <code>
@@ -3521,6 +3710,7 @@ public interface ForecastOptionsOrBuilder
          * found to violate the threshold, and the violation is observed in all
          * forecasts made for the configured `duration`, then the time series is
          * considered to be failing.
+         * The forecast horizon can range from 1 hour to 60 hours.
          * </pre>
          *
          * <code>
@@ -3539,6 +3729,7 @@ public interface ForecastOptionsOrBuilder
          * found to violate the threshold, and the violation is observed in all
          * forecasts made for the configured `duration`, then the time series is
          * considered to be failing.
+         * The forecast horizon can range from 1 hour to 60 hours.
          * </pre>
          *
          * <code>
@@ -3604,6 +3795,7 @@ public static final com.google.protobuf.Descriptors.Descriptor getDescriptor() {
          * found to violate the threshold, and the violation is observed in all
          * forecasts made for the configured `duration`, then the time series is
          * considered to be failing.
+         * The forecast horizon can range from 1 hour to 60 hours.
          * </pre>
          *
          * <code>
@@ -3625,6 +3817,7 @@ public boolean hasForecastHorizon() {
          * found to violate the threshold, and the violation is observed in all
          * forecasts made for the configured `duration`, then the time series is
          * considered to be failing.
+         * The forecast horizon can range from 1 hour to 60 hours.
          * </pre>
          *
          * <code>
@@ -3648,6 +3841,7 @@ public com.google.protobuf.Duration getForecastHorizon() {
          * found to violate the threshold, and the violation is observed in all
          * forecasts made for the configured `duration`, then the time series is
          * considered to be failing.
+         * The forecast horizon can range from 1 hour to 60 hours.
          * </pre>
          *
          * <code>
@@ -4070,6 +4264,7 @@ public Builder mergeFrom(
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4090,6 +4285,7 @@ public boolean hasForecastHorizon() {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4116,6 +4312,7 @@ public com.google.protobuf.Duration getForecastHorizon() {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4144,6 +4341,7 @@ public Builder setForecastHorizon(com.google.protobuf.Duration value) {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4169,6 +4367,7 @@ public Builder setForecastHorizon(com.google.protobuf.Duration.Builder builderFo
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4200,6 +4399,7 @@ public Builder mergeForecastHorizon(com.google.protobuf.Duration value) {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4225,6 +4425,7 @@ public Builder clearForecastHorizon() {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4245,6 +4446,7 @@ public com.google.protobuf.Duration.Builder getForecastHorizonBuilder() {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -4269,6 +4471,7 @@ public com.google.protobuf.DurationOrBuilder getForecastHorizonOrBuilder() {
            * found to violate the threshold, and the violation is observed in all
            * forecasts made for the configured `duration`, then the time series is
            * considered to be failing.
+           * The forecast horizon can range from 1 hour to 60 hours.
            * </pre>
            *
            * <code>
@@ -23511,6 +23714,49 @@ public com.google.monitoring.v3.AlertPolicy.AlertStrategyOrBuilder getAlertStrat
         : alertStrategy_;
   }
 
+  public static final int SEVERITY_FIELD_NUMBER = 22;
+  private int severity_ = 0;
+  /**
+   *
+   *
+   * <pre>
+   * Optional. The severity of an alert policy indicates how important incidents
+   * generated by that policy are. The severity level will be displayed on the
+   * Incident detail page and in notifications.
+   * </pre>
+   *
+   * <code>
+   * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The enum numeric value on the wire for severity.
+   */
+  @java.lang.Override
+  public int getSeverityValue() {
+    return severity_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * Optional. The severity of an alert policy indicates how important incidents
+   * generated by that policy are. The severity level will be displayed on the
+   * Incident detail page and in notifications.
+   * </pre>
+   *
+   * <code>
+   * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The severity.
+   */
+  @java.lang.Override
+  public com.google.monitoring.v3.AlertPolicy.Severity getSeverity() {
+    com.google.monitoring.v3.AlertPolicy.Severity result =
+        com.google.monitoring.v3.AlertPolicy.Severity.forNumber(severity_);
+    return result == null ? com.google.monitoring.v3.AlertPolicy.Severity.UNRECOGNIZED : result;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -23563,6 +23809,10 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (alertStrategy_ != null) {
       output.writeMessage(21, getAlertStrategy());
     }
+    if (severity_
+        != com.google.monitoring.v3.AlertPolicy.Severity.SEVERITY_UNSPECIFIED.getNumber()) {
+      output.writeEnum(22, severity_);
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -23622,6 +23872,10 @@ public int getSerializedSize() {
     if (alertStrategy_ != null) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(21, getAlertStrategy());
     }
+    if (severity_
+        != com.google.monitoring.v3.AlertPolicy.Severity.SEVERITY_UNSPECIFIED.getNumber()) {
+      size += com.google.protobuf.CodedOutputStream.computeEnumSize(22, severity_);
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -23667,6 +23921,7 @@ public boolean equals(final java.lang.Object obj) {
     if (hasAlertStrategy()) {
       if (!getAlertStrategy().equals(other.getAlertStrategy())) return false;
     }
+    if (severity_ != other.severity_) return false;
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -23720,6 +23975,8 @@ public int hashCode() {
       hash = (37 * hash) + ALERT_STRATEGY_FIELD_NUMBER;
       hash = (53 * hash) + getAlertStrategy().hashCode();
     }
+    hash = (37 * hash) + SEVERITY_FIELD_NUMBER;
+    hash = (53 * hash) + severity_;
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -23923,6 +24180,7 @@ public Builder clear() {
         alertStrategyBuilder_.dispose();
         alertStrategyBuilder_ = null;
       }
+      severity_ = 0;
       return this;
     }
 
@@ -24010,6 +24268,9 @@ private void buildPartial0(com.google.monitoring.v3.AlertPolicy result) {
         result.alertStrategy_ =
             alertStrategyBuilder_ == null ? alertStrategy_ : alertStrategyBuilder_.build();
       }
+      if (((from_bitField0_ & 0x00001000) != 0)) {
+        result.severity_ = severity_;
+      }
     }
 
     @java.lang.Override
@@ -24127,6 +24388,9 @@ public Builder mergeFrom(com.google.monitoring.v3.AlertPolicy other) {
       if (other.hasAlertStrategy()) {
         mergeAlertStrategy(other.getAlertStrategy());
       }
+      if (other.severity_ != 0) {
+        setSeverityValue(other.getSeverityValue());
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -24239,6 +24503,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000800;
                 break;
               } // case 170
+            case 176:
+              {
+                severity_ = input.readEnum();
+                bitField0_ |= 0x00001000;
+                break;
+              } // case 176
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -26856,6 +27126,116 @@ public com.google.monitoring.v3.AlertPolicy.AlertStrategyOrBuilder getAlertStrat
       return alertStrategyBuilder_;
     }
 
+    private int severity_ = 0;
+    /**
+     *
+     *
+     * <pre>
+     * Optional. The severity of an alert policy indicates how important incidents
+     * generated by that policy are. The severity level will be displayed on the
+     * Incident detail page and in notifications.
+     * </pre>
+     *
+     * <code>
+     * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The enum numeric value on the wire for severity.
+     */
+    @java.lang.Override
+    public int getSeverityValue() {
+      return severity_;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Optional. The severity of an alert policy indicates how important incidents
+     * generated by that policy are. The severity level will be displayed on the
+     * Incident detail page and in notifications.
+     * </pre>
+     *
+     * <code>
+     * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @param value The enum numeric value on the wire for severity to set.
+     * @return This builder for chaining.
+     */
+    public Builder setSeverityValue(int value) {
+      severity_ = value;
+      bitField0_ |= 0x00001000;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Optional. The severity of an alert policy indicates how important incidents
+     * generated by that policy are. The severity level will be displayed on the
+     * Incident detail page and in notifications.
+     * </pre>
+     *
+     * <code>
+     * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The severity.
+     */
+    @java.lang.Override
+    public com.google.monitoring.v3.AlertPolicy.Severity getSeverity() {
+      com.google.monitoring.v3.AlertPolicy.Severity result =
+          com.google.monitoring.v3.AlertPolicy.Severity.forNumber(severity_);
+      return result == null ? com.google.monitoring.v3.AlertPolicy.Severity.UNRECOGNIZED : result;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Optional. The severity of an alert policy indicates how important incidents
+     * generated by that policy are. The severity level will be displayed on the
+     * Incident detail page and in notifications.
+     * </pre>
+     *
+     * <code>
+     * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @param value The severity to set.
+     * @return This builder for chaining.
+     */
+    public Builder setSeverity(com.google.monitoring.v3.AlertPolicy.Severity value) {
+      if (value == null) {
+        throw new NullPointerException();
+      }
+      bitField0_ |= 0x00001000;
+      severity_ = value.getNumber();
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Optional. The severity of an alert policy indicates how important incidents
+     * generated by that policy are. The severity level will be displayed on the
+     * Incident detail page and in notifications.
+     * </pre>
+     *
+     * <code>
+     * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return This builder for chaining.
+     */
+    public Builder clearSeverity() {
+      bitField0_ = (bitField0_ & ~0x00001000);
+      severity_ = 0;
+      onChanged();
+      return this;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicyOrBuilder.java b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicyOrBuilder.java
index 5e8a65b28b4f..66ab9144266a 100644
--- a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicyOrBuilder.java
+++ b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertPolicyOrBuilder.java
@@ -682,4 +682,37 @@ java.lang.String getUserLabelsOrDefault(
    * <code>.google.monitoring.v3.AlertPolicy.AlertStrategy alert_strategy = 21;</code>
    */
   com.google.monitoring.v3.AlertPolicy.AlertStrategyOrBuilder getAlertStrategyOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * Optional. The severity of an alert policy indicates how important incidents
+   * generated by that policy are. The severity level will be displayed on the
+   * Incident detail page and in notifications.
+   * </pre>
+   *
+   * <code>
+   * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The enum numeric value on the wire for severity.
+   */
+  int getSeverityValue();
+  /**
+   *
+   *
+   * <pre>
+   * Optional. The severity of an alert policy indicates how important incidents
+   * generated by that policy are. The severity level will be displayed on the
+   * Incident detail page and in notifications.
+   * </pre>
+   *
+   * <code>
+   * .google.monitoring.v3.AlertPolicy.Severity severity = 22 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The severity.
+   */
+  com.google.monitoring.v3.AlertPolicy.Severity getSeverity();
 }
diff --git a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertProto.java b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertProto.java
index c0579be51495..6e763e1e8960 100644
--- a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertProto.java
+++ b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/java/com/google/monitoring/v3/AlertProto.java
@@ -107,7 +107,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
           + "monitoring/v3/mutation_record.proto\032\036goo"
           + "gle/protobuf/duration.proto\032\036google/prot"
           + "obuf/wrappers.proto\032\027google/rpc/status.p"
-          + "roto\"\222\"\n\013AlertPolicy\022\014\n\004name\030\001 \001(\t\022\024\n\014di"
+          + "roto\"\242#\n\013AlertPolicy\022\014\n\004name\030\001 \001(\t\022\024\n\014di"
           + "splay_name\030\002 \001(\t\022F\n\rdocumentation\030\r \001(\0132"
           + "/.google.monitoring.v3.AlertPolicy.Docum"
           + "entation\022F\n\013user_labels\030\020 \003(\01321.google.m"
@@ -123,105 +123,109 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
           + "\017mutation_record\030\013 \001(\0132$.google.monitori"
           + "ng.v3.MutationRecord\022G\n\016alert_strategy\030\025"
           + " \001(\0132/.google.monitoring.v3.AlertPolicy."
-          + "AlertStrategy\032J\n\rDocumentation\022\017\n\007conten"
-          + "t\030\001 \001(\t\022\021\n\tmime_type\030\002 \001(\t\022\025\n\007subject\030\003 "
-          + "\001(\tB\004\342A\001\001\032\201\026\n\tCondition\022\014\n\004name\030\014 \001(\t\022\024\n"
-          + "\014display_name\030\006 \001(\t\022Z\n\023condition_thresho"
-          + "ld\030\001 \001(\0132;.google.monitoring.v3.AlertPol"
-          + "icy.Condition.MetricThresholdH\000\022U\n\020condi"
-          + "tion_absent\030\002 \001(\01329.google.monitoring.v3"
-          + ".AlertPolicy.Condition.MetricAbsenceH\000\022U"
-          + "\n\025condition_matched_log\030\024 \001(\01324.google.m"
-          + "onitoring.v3.AlertPolicy.Condition.LogMa"
-          + "tchH\000\022{\n#condition_monitoring_query_lang"
-          + "uage\030\023 \001(\0132L.google.monitoring.v3.AlertP"
-          + "olicy.Condition.MonitoringQueryLanguageC"
-          + "onditionH\000\022{\n#condition_prometheus_query"
-          + "_language\030\025 \001(\0132L.google.monitoring.v3.A"
-          + "lertPolicy.Condition.PrometheusQueryLang"
-          + "uageConditionH\000\0325\n\007Trigger\022\017\n\005count\030\001 \001("
-          + "\005H\000\022\021\n\007percent\030\002 \001(\001H\000B\006\n\004type\032\240\005\n\017Metri"
-          + "cThreshold\022\024\n\006filter\030\002 \001(\tB\004\342A\001\002\0227\n\014aggr"
-          + "egations\030\010 \003(\0132!.google.monitoring.v3.Ag"
-          + "gregation\022\032\n\022denominator_filter\030\t \001(\t\022C\n"
-          + "\030denominator_aggregations\030\n \003(\0132!.google"
-          + ".monitoring.v3.Aggregation\022e\n\020forecast_o"
-          + "ptions\030\014 \001(\0132K.google.monitoring.v3.Aler"
-          + "tPolicy.Condition.MetricThreshold.Foreca"
-          + "stOptions\0228\n\ncomparison\030\004 \001(\0162$.google.m"
-          + "onitoring.v3.ComparisonType\022\027\n\017threshold"
-          + "_value\030\005 \001(\001\022+\n\010duration\030\006 \001(\0132\031.google."
-          + "protobuf.Duration\022D\n\007trigger\030\007 \001(\01323.goo"
-          + "gle.monitoring.v3.AlertPolicy.Condition."
-          + "Trigger\022b\n\027evaluation_missing_data\030\013 \001(\016"
-          + "2A.google.monitoring.v3.AlertPolicy.Cond"
-          + "ition.EvaluationMissingData\032L\n\017ForecastO"
-          + "ptions\0229\n\020forecast_horizon\030\001 \001(\0132\031.googl"
-          + "e.protobuf.DurationB\004\342A\001\002\032\321\001\n\rMetricAbse"
-          + "nce\022\024\n\006filter\030\001 \001(\tB\004\342A\001\002\0227\n\014aggregation"
-          + "s\030\005 \003(\0132!.google.monitoring.v3.Aggregati"
-          + "on\022+\n\010duration\030\002 \001(\0132\031.google.protobuf.D"
-          + "uration\022D\n\007trigger\030\003 \001(\01323.google.monito"
-          + "ring.v3.AlertPolicy.Condition.Trigger\032\275\001"
-          + "\n\010LogMatch\022\024\n\006filter\030\001 \001(\tB\004\342A\001\002\022c\n\020labe"
-          + "l_extractors\030\002 \003(\0132I.google.monitoring.v"
-          + "3.AlertPolicy.Condition.LogMatch.LabelEx"
-          + "tractorsEntry\0326\n\024LabelExtractorsEntry\022\013\n"
-          + "\003key\030\001 \001(\t\022\r\n\005value\030\002 \001(\t:\0028\001\032\210\002\n Monito"
-          + "ringQueryLanguageCondition\022\r\n\005query\030\001 \001("
-          + "\t\022+\n\010duration\030\002 \001(\0132\031.google.protobuf.Du"
-          + "ration\022D\n\007trigger\030\003 \001(\01323.google.monitor"
-          + "ing.v3.AlertPolicy.Condition.Trigger\022b\n\027"
-          + "evaluation_missing_data\030\004 \001(\0162A.google.m"
-          + "onitoring.v3.AlertPolicy.Condition.Evalu"
-          + "ationMissingData\032\373\002\n PrometheusQueryLang"
-          + "uageCondition\022\023\n\005query\030\001 \001(\tB\004\342A\001\002\0221\n\010du"
-          + "ration\030\002 \001(\0132\031.google.protobuf.DurationB"
-          + "\004\342A\001\001\022<\n\023evaluation_interval\030\003 \001(\0132\031.goo"
-          + "gle.protobuf.DurationB\004\342A\001\001\022n\n\006labels\030\004 "
-          + "\003(\0132X.google.monitoring.v3.AlertPolicy.C"
+          + "AlertStrategy\022B\n\010severity\030\026 \001(\0162*.google"
+          + ".monitoring.v3.AlertPolicy.SeverityB\004\342A\001"
+          + "\001\032J\n\rDocumentation\022\017\n\007content\030\001 \001(\t\022\021\n\tm"
+          + "ime_type\030\002 \001(\t\022\025\n\007subject\030\003 \001(\tB\004\342A\001\001\032\201\026"
+          + "\n\tCondition\022\014\n\004name\030\014 \001(\t\022\024\n\014display_nam"
+          + "e\030\006 \001(\t\022Z\n\023condition_threshold\030\001 \001(\0132;.g"
+          + "oogle.monitoring.v3.AlertPolicy.Conditio"
+          + "n.MetricThresholdH\000\022U\n\020condition_absent\030"
+          + "\002 \001(\01329.google.monitoring.v3.AlertPolicy"
+          + ".Condition.MetricAbsenceH\000\022U\n\025condition_"
+          + "matched_log\030\024 \001(\01324.google.monitoring.v3"
+          + ".AlertPolicy.Condition.LogMatchH\000\022{\n#con"
+          + "dition_monitoring_query_language\030\023 \001(\0132L"
+          + ".google.monitoring.v3.AlertPolicy.Condit"
+          + "ion.MonitoringQueryLanguageConditionH\000\022{"
+          + "\n#condition_prometheus_query_language\030\025 "
+          + "\001(\0132L.google.monitoring.v3.AlertPolicy.C"
           + "ondition.PrometheusQueryLanguageConditio"
-          + "n.LabelsEntryB\004\342A\001\001\022\030\n\nrule_group\030\005 \001(\tB"
-          + "\004\342A\001\001\022\030\n\nalert_rule\030\006 \001(\tB\004\342A\001\001\032-\n\013Label"
-          + "sEntry\022\013\n\003key\030\001 \001(\t\022\r\n\005value\030\002 \001(\t:\0028\001\"\255"
-          + "\001\n\025EvaluationMissingData\022\'\n#EVALUATION_M"
-          + "ISSING_DATA_UNSPECIFIED\020\000\022$\n EVALUATION_"
-          + "MISSING_DATA_INACTIVE\020\001\022\"\n\036EVALUATION_MI"
-          + "SSING_DATA_ACTIVE\020\002\022!\n\035EVALUATION_MISSIN"
-          + "G_DATA_NO_OP\020\003:\227\002\352A\223\002\n.monitoring.google"
-          + "apis.com/AlertPolicyCondition\022Fprojects/"
-          + "{project}/alertPolicies/{alert_policy}/c"
-          + "onditions/{condition}\022Porganizations/{or"
-          + "ganization}/alertPolicies/{alert_policy}"
-          + "/conditions/{condition}\022Dfolders/{folder"
-          + "}/alertPolicies/{alert_policy}/condition"
-          + "s/{condition}\022\001*B\013\n\tcondition\032\327\003\n\rAlertS"
-          + "trategy\022f\n\027notification_rate_limit\030\001 \001(\013"
-          + "2E.google.monitoring.v3.AlertPolicy.Aler"
-          + "tStrategy.NotificationRateLimit\022-\n\nauto_"
-          + "close\030\003 \001(\0132\031.google.protobuf.Duration\022r"
-          + "\n\035notification_channel_strategy\030\004 \003(\0132K."
-          + "google.monitoring.v3.AlertPolicy.AlertSt"
-          + "rategy.NotificationChannelStrategy\032B\n\025No"
-          + "tificationRateLimit\022)\n\006period\030\001 \001(\0132\031.go"
-          + "ogle.protobuf.Duration\032w\n\033NotificationCh"
-          + "annelStrategy\022\"\n\032notification_channel_na"
-          + "mes\030\001 \003(\t\0224\n\021renotify_interval\030\002 \001(\0132\031.g"
-          + "oogle.protobuf.Duration\0321\n\017UserLabelsEnt"
-          + "ry\022\013\n\003key\030\001 \001(\t\022\r\n\005value\030\002 \001(\t:\0028\001\"a\n\025Co"
-          + "nditionCombinerType\022\027\n\023COMBINE_UNSPECIFI"
-          + "ED\020\000\022\007\n\003AND\020\001\022\006\n\002OR\020\002\022\036\n\032AND_WITH_MATCHI"
-          + "NG_RESOURCE\020\003:\311\001\352A\305\001\n%monitoring.googlea"
-          + "pis.com/AlertPolicy\022/projects/{project}/"
-          + "alertPolicies/{alert_policy}\0229organizati"
-          + "ons/{organization}/alertPolicies/{alert_"
-          + "policy}\022-folders/{folder}/alertPolicies/"
-          + "{alert_policy}\022\001*B\305\001\n\030com.google.monitor"
-          + "ing.v3B\nAlertProtoP\001ZAcloud.google.com/g"
-          + "o/monitoring/apiv3/v2/monitoringpb;monit"
-          + "oringpb\252\002\032Google.Cloud.Monitoring.V3\312\002\032G"
-          + "oogle\\Cloud\\Monitoring\\V3\352\002\035Google::Clou"
-          + "d::Monitoring::V3b\006proto3"
+          + "nH\000\0325\n\007Trigger\022\017\n\005count\030\001 \001(\005H\000\022\021\n\007perce"
+          + "nt\030\002 \001(\001H\000B\006\n\004type\032\240\005\n\017MetricThreshold\022\024"
+          + "\n\006filter\030\002 \001(\tB\004\342A\001\002\0227\n\014aggregations\030\010 \003"
+          + "(\0132!.google.monitoring.v3.Aggregation\022\032\n"
+          + "\022denominator_filter\030\t \001(\t\022C\n\030denominator"
+          + "_aggregations\030\n \003(\0132!.google.monitoring."
+          + "v3.Aggregation\022e\n\020forecast_options\030\014 \001(\013"
+          + "2K.google.monitoring.v3.AlertPolicy.Cond"
+          + "ition.MetricThreshold.ForecastOptions\0228\n"
+          + "\ncomparison\030\004 \001(\0162$.google.monitoring.v3"
+          + ".ComparisonType\022\027\n\017threshold_value\030\005 \001(\001"
+          + "\022+\n\010duration\030\006 \001(\0132\031.google.protobuf.Dur"
+          + "ation\022D\n\007trigger\030\007 \001(\01323.google.monitori"
+          + "ng.v3.AlertPolicy.Condition.Trigger\022b\n\027e"
+          + "valuation_missing_data\030\013 \001(\0162A.google.mo"
+          + "nitoring.v3.AlertPolicy.Condition.Evalua"
+          + "tionMissingData\032L\n\017ForecastOptions\0229\n\020fo"
+          + "recast_horizon\030\001 \001(\0132\031.google.protobuf.D"
+          + "urationB\004\342A\001\002\032\321\001\n\rMetricAbsence\022\024\n\006filte"
+          + "r\030\001 \001(\tB\004\342A\001\002\0227\n\014aggregations\030\005 \003(\0132!.go"
+          + "ogle.monitoring.v3.Aggregation\022+\n\010durati"
+          + "on\030\002 \001(\0132\031.google.protobuf.Duration\022D\n\007t"
+          + "rigger\030\003 \001(\01323.google.monitoring.v3.Aler"
+          + "tPolicy.Condition.Trigger\032\275\001\n\010LogMatch\022\024"
+          + "\n\006filter\030\001 \001(\tB\004\342A\001\002\022c\n\020label_extractors"
+          + "\030\002 \003(\0132I.google.monitoring.v3.AlertPolic"
+          + "y.Condition.LogMatch.LabelExtractorsEntr"
+          + "y\0326\n\024LabelExtractorsEntry\022\013\n\003key\030\001 \001(\t\022\r"
+          + "\n\005value\030\002 \001(\t:\0028\001\032\210\002\n MonitoringQueryLan"
+          + "guageCondition\022\r\n\005query\030\001 \001(\t\022+\n\010duratio"
+          + "n\030\002 \001(\0132\031.google.protobuf.Duration\022D\n\007tr"
+          + "igger\030\003 \001(\01323.google.monitoring.v3.Alert"
+          + "Policy.Condition.Trigger\022b\n\027evaluation_m"
+          + "issing_data\030\004 \001(\0162A.google.monitoring.v3"
+          + ".AlertPolicy.Condition.EvaluationMissing"
+          + "Data\032\373\002\n PrometheusQueryLanguageConditio"
+          + "n\022\023\n\005query\030\001 \001(\tB\004\342A\001\002\0221\n\010duration\030\002 \001(\013"
+          + "2\031.google.protobuf.DurationB\004\342A\001\001\022<\n\023eva"
+          + "luation_interval\030\003 \001(\0132\031.google.protobuf"
+          + ".DurationB\004\342A\001\001\022n\n\006labels\030\004 \003(\0132X.google"
+          + ".monitoring.v3.AlertPolicy.Condition.Pro"
+          + "metheusQueryLanguageCondition.LabelsEntr"
+          + "yB\004\342A\001\001\022\030\n\nrule_group\030\005 \001(\tB\004\342A\001\001\022\030\n\nale"
+          + "rt_rule\030\006 \001(\tB\004\342A\001\001\032-\n\013LabelsEntry\022\013\n\003ke"
+          + "y\030\001 \001(\t\022\r\n\005value\030\002 \001(\t:\0028\001\"\255\001\n\025Evaluatio"
+          + "nMissingData\022\'\n#EVALUATION_MISSING_DATA_"
+          + "UNSPECIFIED\020\000\022$\n EVALUATION_MISSING_DATA"
+          + "_INACTIVE\020\001\022\"\n\036EVALUATION_MISSING_DATA_A"
+          + "CTIVE\020\002\022!\n\035EVALUATION_MISSING_DATA_NO_OP"
+          + "\020\003:\227\002\352A\223\002\n.monitoring.googleapis.com/Ale"
+          + "rtPolicyCondition\022Fprojects/{project}/al"
+          + "ertPolicies/{alert_policy}/conditions/{c"
+          + "ondition}\022Porganizations/{organization}/"
+          + "alertPolicies/{alert_policy}/conditions/"
+          + "{condition}\022Dfolders/{folder}/alertPolic"
+          + "ies/{alert_policy}/conditions/{condition"
+          + "}\022\001*B\013\n\tcondition\032\327\003\n\rAlertStrategy\022f\n\027n"
+          + "otification_rate_limit\030\001 \001(\0132E.google.mo"
+          + "nitoring.v3.AlertPolicy.AlertStrategy.No"
+          + "tificationRateLimit\022-\n\nauto_close\030\003 \001(\0132"
+          + "\031.google.protobuf.Duration\022r\n\035notificati"
+          + "on_channel_strategy\030\004 \003(\0132K.google.monit"
+          + "oring.v3.AlertPolicy.AlertStrategy.Notif"
+          + "icationChannelStrategy\032B\n\025NotificationRa"
+          + "teLimit\022)\n\006period\030\001 \001(\0132\031.google.protobu"
+          + "f.Duration\032w\n\033NotificationChannelStrateg"
+          + "y\022\"\n\032notification_channel_names\030\001 \003(\t\0224\n"
+          + "\021renotify_interval\030\002 \001(\0132\031.google.protob"
+          + "uf.Duration\0321\n\017UserLabelsEntry\022\013\n\003key\030\001 "
+          + "\001(\t\022\r\n\005value\030\002 \001(\t:\0028\001\"a\n\025ConditionCombi"
+          + "nerType\022\027\n\023COMBINE_UNSPECIFIED\020\000\022\007\n\003AND\020"
+          + "\001\022\006\n\002OR\020\002\022\036\n\032AND_WITH_MATCHING_RESOURCE\020"
+          + "\003\"J\n\010Severity\022\030\n\024SEVERITY_UNSPECIFIED\020\000\022"
+          + "\014\n\010CRITICAL\020\001\022\t\n\005ERROR\020\002\022\013\n\007WARNING\020\003:\311\001"
+          + "\352A\305\001\n%monitoring.googleapis.com/AlertPol"
+          + "icy\022/projects/{project}/alertPolicies/{a"
+          + "lert_policy}\0229organizations/{organizatio"
+          + "n}/alertPolicies/{alert_policy}\022-folders"
+          + "/{folder}/alertPolicies/{alert_policy}\022\001"
+          + "*B\305\001\n\030com.google.monitoring.v3B\nAlertPro"
+          + "toP\001ZAcloud.google.com/go/monitoring/api"
+          + "v3/v2/monitoringpb;monitoringpb\252\002\032Google"
+          + ".Cloud.Monitoring.V3\312\002\032Google\\Cloud\\Moni"
+          + "toring\\V3\352\002\035Google::Cloud::Monitoring::V"
+          + "3b\006proto3"
     };
     descriptor =
         com.google.protobuf.Descriptors.FileDescriptor.internalBuildGeneratedFileFrom(
@@ -253,6 +257,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
               "CreationRecord",
               "MutationRecord",
               "AlertStrategy",
+              "Severity",
             });
     internal_static_google_monitoring_v3_AlertPolicy_Documentation_descriptor =
         internal_static_google_monitoring_v3_AlertPolicy_descriptor.getNestedTypes().get(0);
diff --git a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/proto/google/monitoring/v3/alert.proto b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/proto/google/monitoring/v3/alert.proto
index b746a5e47d52..8dafe88a235a 100644
--- a/java-monitoring/proto-google-cloud-monitoring-v3/src/main/proto/google/monitoring/v3/alert.proto
+++ b/java-monitoring/proto-google-cloud-monitoring-v3/src/main/proto/google/monitoring/v3/alert.proto
@@ -135,6 +135,7 @@ message AlertPolicy {
         // found to violate the threshold, and the violation is observed in all
         // forecasts made for the configured `duration`, then the time series is
         // considered to be failing.
+        // The forecast horizon can range from 1 hour to 60 hours.
         google.protobuf.Duration forecast_horizon = 1
             [(google.api.field_behavior) = REQUIRED];
       }
@@ -544,6 +545,25 @@ message AlertPolicy {
     repeated NotificationChannelStrategy notification_channel_strategy = 4;
   }
 
+  // An enumeration of possible severity level for an Alert Policy.
+  enum Severity {
+    // No severity is specified. This is the default value.
+    SEVERITY_UNSPECIFIED = 0;
+
+    // This is the highest severity level. Use this if the problem could
+    // cause significant damage or downtime.
+    CRITICAL = 1;
+
+    // This is the medium severity level. Use this if the problem could
+    // cause minor damage or downtime.
+    ERROR = 2;
+
+    // This is the lowest severity level. Use this if the problem is not causing
+    // any damage or downtime, but could potentially lead to a problem in the
+    // future.
+    WARNING = 3;
+  }
+
   // Required if the policy exists. The resource name for this policy. The
   // format is:
   //
@@ -641,4 +661,9 @@ message AlertPolicy {
 
   // Control over how this alert policy's notification channels are notified.
   AlertStrategy alert_strategy = 21;
+
+  // Optional. The severity of an alert policy indicates how important incidents
+  // generated by that policy are. The severity level will be displayed on the
+  // Incident detail page and in notifications.
+  Severity severity = 22 [(google.api.field_behavior) = OPTIONAL];
 }