The day may start with a light predawn shower and end with a possible late afternoon or evening shower. But if the gradient wind has a southerly component in it,
Caribbean heat and moisture will build Cumulo Nimbus in the mountains with daytime heating. When daytime heating subsides due to western cloud cover or the setting
of the sun, storm cells can roll down to the north coast and off the lee sides of the capes. This will occur between 6p.m. and midnight, after which all goes clear.

Rising warm air creates most storm cells. These rotate CCW. Down-spikes from upper air occassionally create CW rotating cells. You will feel warm humid air preceeding the CCW cell but cool air from the CWs. If the harbor gets straddled by two cells, one CW and the other a CCW, up to 60 knots N or S wind can result.