SoftwareSerial buffer size

I deleted:

char tempSlaveChars[numCharsSlave];        // temporary array for use when parsing
char messageFromSlave[numCharsSlave] = {0};

And changed this:

strtokIndx = strtok(tempSlaveChars, "*");     // get the first part - the string

to this:

 strtokIndx = strtok(receivedSlaveChars, "*");     // get the first part - the string

I believe this is what you suggested me.

This is what goes through now:

Rain sensor: 1
Sensor light: 2.22
Sensor humidity: 3.33
Sensor temperature: 4.44
API rain: 5.55
API temperature: 6.66
API temperature feels: 7.77
API humidity: 8
API wind: 123456789012345678901234567890123456789012345678901234
API weather: 12345678901234567890123456789
API Text tomorrow: 12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
API Text tomorrow night:

I am using Arduino Mega for the master. Woulnd't that have more SRAM than the Uno?

Also, when changing numCharsSlave to 600, I receive this:

Rain sensor: 1
Sensor light: 2.22
Sensor humidity: 3.33
Sensor temperature: 4.44
API rain: 5.55
API temperature: 6.66
API temperature feels: 7.77
API humidity: 8
API wind: 123456789012345678901234567890123456789012
API weather:
API Text tomorrow:
API Text tomorrow night: