Windows in Mississippi swell, sweat, and leak because the air stays wet and the storms come in sideways. A wood sash in an older town house that will not close in August is not a fogged ranch unit and not a coastal opening that took wind-driven rain. Say which one you are standing in front of.
River humidity swells the meeting rail until the latch misses, then a dry week shrinks it and the sash rattles. Summer coils that chill without drying the room leave the glass running with water, and the stool stays dark. Fog between panes means the seal is gone. Painted-shut cords in Vicksburg, Natchez, and Columbus plaster walls fail quietly until the lower sash drops. Those are different jobs.
On the coast, rain is blown at the window the way a hose would be aimed at it. The glass can be whole while the sill and the wall cavity are soaked. Inland hail may pit an older screen and leave the unit itself intact, or it may crack a pane on the exposed side. Brick-veneer flanges that were caulked instead of flashed weep into the opening every strong storm. The stain under the apron is the proof.
Look after the rain, not only during it. A bubble in plaster, soft wood at the corners, or mildew on the stool means the path is already open. If the bedroom window must still open, say so. If the only goal is to stop water, say that too. Count the bad openings in plain words. A whole-house speech about drafts wastes the call when one west wall is the problem.
Call with the town, the floor, and the wall that faces the weather. Delta cottage, pine-belt ranch, bluff house, or a coastal cottage on piers. Say whether the sash is wood, metal, or a later insert, and whether the water came over the meeting rail or around the frame. Mention if the trim is soft. The trade starts from that opening, not from a wish for a quieter room. Call the number on this page.