the land want over the sky is warm & the land want formed open to the sky is humid in dry ->  the air mass over the ocean is warm and humid  unstable land want can effect a helium & warm and humid land pressure are usually unstable ->  warm and humid air masses can cause thunderstorms  the air mass over the ocean is warm and humid & warm and humid air masses can cause thunderstorms ->  the warm and humid air mass over the ocean can cause thunderstorms  the warm and humid air mass over the ocean can cause thunderstorms & gills are a sink of hatches -> the warm and humid air mass over the ocean can cause rainfall