SRX is not sharing the severity of the individual traps generated on the SRX device with the external SNMP server.

Traps are unsolicited messages from an SNMP agent to remote network management systems or trap receivers. Enterprises use SNMP traps as part of a fault-monitoring solution in addition to system logging. In Junos OS, we must configure a trap group to use SNMP traps.
 

In the group, we define the categories, with the defined category SRX will generate the traps and pass the information to the external server.
 

SRX device will not share the severity of the traps with the SNMP server. This is because SNMP traps are generated based on the category and not severity. Hence SRX cannot share the severity of the SNMP traps with the external SNMP server.