Three boys were in hospital, two with serious head injuries, after a tree fell on them.
The trio of nine-year-olds were waiting to use the practice nets at Spencer Cricket Club in Earlsfield, south west London, when the tree crashed down.
The boys, one of whom suffered leg injuries, were rushed to hospital and the club suspended all play.
Monique Wilkinson, 33, was staging a birthday party for her three-year-old daughter at her home when she heard the tree fall.
Reliving the horror, she said: "We could see the kids stuck under the tree and there were a lot of people around. It's terrible. These kids play on the field every weekend.
"The air ambulance landed in the field across the road from us and there were four or five ambulances in total. The emergency services seemed to have everything under control. Another tree came down on this road earlier in the day which shows how bad the winds were."
The incident happened on Saturday after strong winds buffeted parts of south London.
A statement from the club said the boys' conditions were being assessed and: "Naturally, the club's thoughts are with those young ones and their families.
"As soon as we have had word from the hospital and the parents we shall be issuing another statement.
"In the meantime, all cricket at the ground has been suspended."