People have a tendency to instinctively run to inside a shelter or vehicle to avoid getting wet or drenched when it starts to rain all of a sudden. Some are worried about their appearances and get concerned about spoiling their hair or a costly makeup when the rain comes down pouring. These are, after all, simple concerns related to ones appearance and is in no way classifiable as a real fear of rain.
People with pluviophobia or ombrophobia develop increased anxiousness following a heavy rainfall weather forecast. In some cases people may want to stock household and other items as a preventive measure.
The most obvious reason for this phobia taking root is that a person has experienced a traumatic event or episode involving rain in the past, such as in childhood. In some cases, pluviophobia causes the phobic personality to lookout for signs of black clouds or even thunder and lightning, which may summon rain.
An immediate response from a person with fear of rain would be to take measures that would make it less likely for him or her to go out in the rain. Other pluviophobia causes include learned fear.
An pluviophobe would be more interested in weather reports to get clues of any impending rainfall. If the phobic person thinks there is even a small likelihood of rain falling, he or she may avoid venturing outside. He or she will feel secure in an enclosed environment such as home or work place, but may start to show pluviophobia symptoms such as panic if trapped outside in even a mild rainfall.
Treatment may include psychotherapy. Medications are not usually needed because it does not rain every day.