For temperature, it is usually easy to find some data, e.g. from reanalysis datasets (ERA-Interim). For rainfall several datasets are available, also in real time. See the replies to this question: https://www.researchgate.net/post/Can_I_get_a_free_source_of_daily_rainfall_data_for_the_entire_globe_Satellite_derived_data_can_also_serve_the_purpose

And also the dataset provided with this our paper recently published on JGR: https://www.researchgate.net/publication/261675491_Soil_as_a_natural_raingauge_estimating_global_rainfall_from_satellite_soil_moisture_data

Article Soil as a natural rain gauge: Estimating global rainfall fro...

you can download the weather database from your station going through this site...

i have checked it for my site by comparing the available data with the data obtained from the database.... This format database is specifically designed for SWAT model, but you can use change it... Here s the link:

http://globalweather.tamu.edu/

One more thing you can do is that, you can set the model for a area which is having nearly same characteristics as that of your study area, then after that you can validate the same model by using the data of your study area.. this type of study has been performed earlier for those watersheds which doesn't have enough data for performing calibration and validation...

if required i can sent you the paper....

You can download TRMM gridded rainfall data for your study area.

You can also try to generate a synthetic daily rainfall data based on the monthly data and the maximum precipitation in one day of that month. Some meteorological stations record other usefull parameters such as number of rainfall days in the month and the maximum precipitation fell in the month.

I did that for my thesis dissertation. You can find my thesis at this link

http://biomath.ugent.be/biomath/publications/download/matamorosdavid_phd.pdf

Hy,

You can find important data here http://freegisdata.rtwilson.com/