You can just reduce the resistor to keep the voltage within range over the expected temperature range.
Keep in mind that if the temperature sensor wires get shorted the MCU will likely be destroyed. It's also not very good to run long wires directly to the MCU pins.
I suggest adding a resistor of 1-5K in series with the ADC input and a capacitor from the ADC input to ground of 100nF X7R.
simulate this circuit – Schematic created using CircuitLab
Do pay attention to Equation 1 in the microcontroller datasheet to ensure that you are not exceeding the maximum sample rate for the input impedance (which will be your load resistor plus the series resistor I mentioned plus Radc - the 6K ADC sampling switch resistance). Since the AD590 sensors respond with glacial swiftness by ADC standards, you can simply keep the sample rate within reason and you won't lose any information.
Also note that you will not be able to get a full 3.3V out of the AD590 with only a 5V supply. Check the datasheet. You may be limited to 1V to get guaranteed accuracy.