Answer
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
Heavy rains and severe, cold wind may justify combining prayers in winter when they cause hardship for people to attend congregational prayers.
Answering your question, Dr. Muhammad Salama, PhD, Islamic Studies in English, Associate Professor at the Faculty of Islamic Sciences al-Madinah International University (Mediu), states:
Winter itself is not a justification for combining prayers (Zhuhr and Asr together and Maghrib and Isha together).
However, heavy rains and severe, cold wind may justify combining prayers in winter when they cause hardship for people to attend congregational prayers.
Thus, this rukhsah (license) is given to those who attend congregational prayers and find it difficult in these bad conditions to attend every congregational Prayer.
Heavy rains was a reason for combining prayers during the lifetime of Prophet Muhammad (peace be upon him). Ibn Abbas said: “The Messenger of Allah combined Zhuhr and Asr together and Maghrib and Isha together in Medina without being in a state of danger or rainfall.” (Muslim)
This implies that combining prayers during rainfalls was practiced widely. Severe and cold wind is analogous to heavy rainfalls, according to the Hanbalite School of Fiqh.
Almighty Allah knows best.