sentences:  Iceland, especially inland and during winter, is frequently subject to abrupt and dramatic changes in weather that can sharply reduce visibility, as well as rapidly increasing wind speed and precipitation, and shift temperature.Generally, wind speeds tend to be higher in the highlands, but topographical features can aggravate winds and cause strong gusts in lowland areas.Wind speed in the lowlands reaches on 10–20 days per year, but on upwards of 50 days per year in places in the highlands.