The modern language you are looking for is called modern Fortran 2018. Fortran 2008 and 2018 have everything a numerical computing project would need and so many features that many other languages mentioned here lack (including extremely pleasant array-syntax which has inspired all other languages such as MATLAB, Python, R, Julia, ..., even C++ numerical ...
As a former Fortran programmer I did a small online review several weeks ago into current trends for scientific programming.
To begin with, despite its age and its sometimes archaic style of programming, because of its huge legacy, Fortran isn't being directed to the trash can in a hurry. It's going to be used for a long time to come.
Like you, others have ...
I am presently working on exactly this.
I am using climate reanalysis data, to fill in the 'empties' since my climate stations are far away from each other. Or, sometime, I have N/A's in my series that I would like to fill-in or relate.
From the Copernicus site:
Climate reanalyses combine past observations with models to generate consistent time series of ...
Right now, I think that Julia makes the cut, because it provides a great tradeoff between "fast scripting" and "high-performance scientific computing".
But I am willing to hear other people's opinions, perhaps I have overlooked something.