You can use the Windows magnifier to make the windicator as big as you like, but it gets a bit pixellated at high magnifications.
Another advantage of using the magnifier for this is you can put the magnifier lens wherever you want on the screen...
NOTE : I don't think this works with overlays as the magnifier window is always on top.
HOW TO :
1.) Open up the game and Windows 10 settings.
2.) In Windows 10 settings click on Ease of Access then Magnifier in the left pane.
3.) On the Magnifier page (leave the magnifier set to off for the moment) choose the Zoom level you want. (This can be modified later if set too high or low initially).
4.) Next set the Magnifier View to Docked. Underneath that set the Magnifier to Follow the Mouse Pointer.
5.) Go back to the top of the page and turn the magnifier to On.
6.) If the magnifier lens is stuck to one of your screen edges, move your mouse over the lens until it changes to a move cursor, then click and drag it away from the screen edge. The magnifier lens should then change to a smaller undocked window.
7.) Go back to the game and set the game window size/position up for playing and start a game just to set up the wind indicator.
8.) Hover your cursor over the wind arrow so that it appears in the magnifier window. You can adjust the zoom level by pressing the Windows key & '+' to zoom in or the Windows key & '-' to zoom out. When you are happy with the zoom level and position of the image in the magnifier window, let go of the mouse and don't move it.
9.) Use Alt + Tab on your keyboard to go back to the Windows 10 magnifier settings page. Then use the Tab key to highlight the Mouse Pointer option, when selected, hit the spacebar to uncheck it. If you accidently go past the mouse pointer check box, use Shift + Tab to go back.
10.) Now you can use the mouse again. Go back to the game to re-position / re-size the magnifier window to what you want.
11.) Done! You can close the magnifier settings page if you wish.