When the Weather Is Fine

Director

• 
  Han Ji Seung

Executive Producer

• 
  Oh Hwan Min

Screenwriter

• 
  Han Ga Ram

Main Role

• 
  Park Min Young

  Mok Hae Won

  Main Role
• 
  Seo Kang Jun

  Im Eun Seob

  Main Role

Support Role

• 
  Lee Jae Wook

  Lee Jang Woo [Eun Seob's friend]

  Support Role
• 
  Kim Hwan Hee

  Im Hwi [Eun Seob's sister]

  Support Role
• 
  Moon Jung Hee

  Shim Myung Yeo [Hae Won's aunt]

  Support Role
• 
  Im Se Mi

  Kim Bo Young [Hae Won's former friend]

  Support Role
• 
  Jin Hee Kyung

  Shim Myung Joo [Hae Won's mother]

  Support Role
• 
  Nam Gi Ae

  Yoon Yeo Jung [Eun Seob's mother]

  Support Role
• 
  Kang Shin Il

  Im Jong Pil [Eun Seob's father]

  Support Role
• 
  Lee Seon Hee

  Choi Soo Jung [Myung Yeo's friend]

  Support Role
• 
  Choo Ye Jin

  Kwon Hyeon Ji [Hwi's friend]

  Support Role
• 
  Lee Tae Hyung

  Bae Geun Sang [Goodnight book club member]

  Support Role
• 
  Han Chang Min

  Jung Seung Ho [Goodnight book club member]

  Support Role
• 
  Lee Young Suk

  Jung Gil Bok [Seung Ho's grandfather]

  Support Role
• 
  Hwang Geon

  Cha Yoon Taek [Editor / Myung Yeo's ex-boyfriend]

  Support Role
• 
  Kim Dae Geon

  Kim Young Soo [Hwi's crush]

  Support Role
• 
  Yang Hye Ji

  Ji Eun Shil [Jang Woo's first love]

  Support Role
• 
  Lee Bong Ryun

  Jang Ha Nim [Pharmacist]

  Support Role
• 
  Shin Hyun Jong

  [Village chief]

  Support Role
• 
  Choi Yun Seol

  Ji Yun [High school alumnus]

  Support Role
• 
  Park Han Sol

  Joo Hee [Bo Yeong's classmate]

  Support Role
• 
  Lee Ha Eum

  Kim Sul Ah

  Support Role
• 
  Gu Bon Jin

  Inspector Kim (Ep. 15)

  Support Role

Guest Role

• 
  Gu Da Song

  Na Gyung [Cello student] (Ep. 1)

  Guest Role
• 
  Noh Jae Hoon

  Park Joong Hee [High school alumnus] (Ep. 1, 6)

  Guest Role
• 
  Yoon Ji Hye

  Choi Ji Young [High school alumnus] (Ep. 1, 6)

  Guest Role
• 
  Moon Yong Il

  Yoon Jo [High school alumnus] (Ep. 1, 6)

  Guest Role
• 
  Kim Young Sun

  [Na Gyeong's mother] (Ep. 1)

  Guest Role
• 
  Lee Yoo Jung

  [Music Institute owner] (Ep. 1)

  Guest Role
• 
  Seo Dong Oh

  [High school alumnus] (Ep. 1, 16)

  Guest Role
• 
  Cha Yoo Joo

  [High school alumnus] (Ep. 1, 6)

  Guest Role
• 
  Park Seo Kyung

  Mok Hae Won [Young] (Ep. 2, 11-12, 14)

  Guest Role
• 
  Lee Young Ran

  Yoon Hye Ja [Hae Won's grandmother] (Ep. 2, 3, 5, 12)

  Guest Role
• 
  Uhm Hye Soo

  [Hae Won's classmate] (Ep. 2-3)

  Guest Role
• 
  Park Jung Eon

  Kim Jung Eun [Judge] (Ep. 3, 5, 12)

  Guest Role
• 
  Im Yu Ran

  [Student's mother] (Ep. 3)

  Guest Role
• 
  Choi Ji Yeon

  Ji Yeon [City Hall employee] (Ep. 4, 11, 14)

  Guest Role
• 
  Park Ji Won

  Choi Min Jung [City hall employee] (Ep. 4, 9)

  Guest Role
• 
  Ahn Soo Ho

  [Jang Woo's boss] (Ep. 4, 7, 14)

  Guest Role
• 
  Lee Se Rang

  [City Hall employee] (Ep. 4, 11, 14)

  Guest Role
• 
  Jeon Yu Lim

  Shim Myung Joo [Young] (Ep. 5)

  Guest Role
• 
  Yoon Sang Hwa

  Park Hin Dol [Century Seorim bookstore] (Ep. 5-6, 9, 16)

  Guest Role
• 
  Seo Tae Hwa

  Mok Joo Hong [Hae Won's father] (Ep. 5, 11-12, 15)

  Guest Role
• 
  Ok Chan Yu

  Im Eun Seob / Kim Jin Ho [Young] (Ep. 5, 8-10)

  Guest Role
• 
  Jung Nan Hee

  [Florist] (Ep. 5, 13-14)

  Guest Role
• 
  Jun Eun Mi

  [Prison officer] (Ep. 5)

  Guest Role
• 
  Kim Young Dae

  Oh Young Woo [High school alumnus / Barista] (Ep. 5, 6, 16)

  Guest Role
• 
  Kim Hong Bin

  Shim Myung Yeo [Young] (Ep. 6, 8, 11)

  Guest Role
• 
  Kim Hye Hwa

  [Kim Jin Ho's mother] (Ep. 7-8, 10)

  Guest Role
• 
  Kim Chae Hyun

  [Bo Young's co-worker] (Ep. 7)

  Guest Role
• 
  Jeon Yeong In

  Bo Gook (Ep. 8)

  Guest Role
• 
  Ahn Dong Goo

  Cha Yun Taek [Young] (Ep. 8, 11)

  Guest Role
• 
  Oh Ja Hun

  Lee Jang Woo [Young] (Ep. 9)

  Guest Role
• 
  Kim Na Mi

  Shin Young Chun [Author] (Ep. 9, 11, 13)

  Guest Role
• 
  Kang Jin Hwi

  Gil Dong [Eun Seob's Uncle] (Ep. 9-10)

  Guest Role
• 
  Yoo Joo Won

  [School kid who teases Eun Sub] (Ep. 9)

  Guest Role
• 
  Shin Young Kyu

  [Waiter] (Ep. 10)

  Guest Role
• 
  Keum Dong Hyun

  [Billiard Hall owner] (Ep. 10)

  Guest Role
• 
  Lee Seo An

  Jo Young Mi [Jang Woo's blind date] (Ep. 11)

  Guest Role
• 
  Uhm Tae Ok

  [Mourner] (Ep. 11)

  Guest Role
• 
  Yoo Soon Woong

  [Bookstore landlord] (Ep. 11)

  Guest Role
• 
  Bae Min Jun

  [Teenager on bench] (Ep. 12)

  Guest Role
• 
  Yoon Boo Jin

  [Friend of Bo Young's mother] (Ep. 13)

  Guest Role
• 
  Oh Se Eun

  Song Je In [Yeong Su's classmate] (Ep. 14-15)

  Guest Role
• 
  Choi Chung Ja

  [Villager] (Ep. 14)

  Guest Role
• 
  Kim Bi Bi

  [Ophthalmologist] (Ep. 14)

  Guest Role
• 
  Jeon Young

  [Ji Eun Shil’s mother] (Ep. 14)

  Guest Role
• 
  Kim Nu Rim

  Im Hwi [Transfer student] (Ep. 16)

  Guest Role
• 
  Park In Chun

  [Journalist] (Ep. 16)

  Guest Role
• 
  Hong Boo Hyang

  [Mi Yeon's mother] (Ep. 16)

  Guest Role
• 
  Ahn So Ye

  [Village kid]

  Guest Role
• 
  Shin Dong Hoon

  [City Hall employee]

  Guest Role
• 
  Seo Han Sol

  [Young Woo's friend]

  Guest Role
• 
  Kim Yun Jeong

  [High School student]

  Guest Role
• 
  Yoo Ok Joo

  [Kim Bo Young's mother]

  Guest Role
• 
  Yoon Felix

  Park Hin Dol [Young]

  Guest Role

Unknown

• 
  Shin Hye Ji Unknown
• 
  Kim Hye Ji Unknown
• 
  Son Sang Bin Unknown
• 
  Han Ji Won Unknown
• 
  Park Seo Bin Unknown
• 
  Kang Sung Chan Unknown
• 
  Min Chae Min Unknown