A question that someone here might be able to help with please:

Is it possible to get any idea of the likely pressure gradient
associated with wind over relatively short distances, eg 500-1000m - say
one end of a level field to the other?

Presumably there has to be some difference in pressure for the wind to
blow at all, but I'm guessing that even for a significant say 20kt wind
blowing directly along the length of the field then the difference over
1km might be relatively tiny, say 0.1mb?