No. God's knowledge must be altogether invariable because the knowledge of God is His substance (Q14, A4) and His substance is altogether immutable (Q9, A1).
The knowledge of God, however, would be variable if He knew enunciable things by way of enunciation, by composition and division, as occurs in our intellect. But He has instead knowledge of vision, according to which He is said to know those things which are in act in some period of time.
From the fact that He knows some things might be which are not, or that some things might not be which are, it does not follow that His knowledge is variable, but rather that He knows the variability of things.
If, however, anything existed which God did not previously know, and afterwards knew, then His knowledge would be variable. But this could not be; for whatever is, or can be in any period of time, is known by God in His eternity. Therefore from the fact that a thing exists in some period of time, it follows that it is known by God from eternity.