Forecasting Love and Weather

KMA meteorologist Jin Ha-kyung struggles with the hardships of her work as the agency fails to forecast a hailstorm that struck the capital area, amidst the pressure of her upcoming marriage with co-employee Han Ki-joon. Junior meteorologist Lee Shi-woo, who was one of the very few staff who saw earlier the possibility for hail, tries to convince the headquarters of a potential late afternoon rainshower. Ha-kyung discovers Ki-joon sleeping with weather journalist Chae Yoo-jin, who later breaks up with her boyfriend Shi-woo.

Two months later, Ha-kyung is promoted upon the resignation of her predecessor, and Shi-woo is transferred to the KMA headquarters for his excellent forecasting skills; Ki-joon and Yoo-jin are married. Ha-kyung, Shi-woo and other KMA meteorologists try to pinpoint the cause of the near-freezing temperatures in the Korean peninsula amid the spring season. Ha-kyung and Ki-joon clash at work over who inherits their apartment. Later, Ha-kyung and Shi-woo have a drink and talk about the two people who messed up with both of their love lives.

After having a drunken one-night stand, Ha-kyung and Shi-woo agree to pretend nothing at all happened between them. The KMA is pressured by fisherfolks to lift the Wind Wave Warning (풍랑경보 pungnanggyeongbo)^[25][26] that has been in effect for two days. Ha-kyung insists extending the Warning until there is enough evidence for it to be downgraded to Wind Wave Advisory (풍랑주의보 pungnangju-uibo)^[25][26] or be lifted entirely. Later, Ha-kyung starts having feelings for Shi-woo, who admits that he would not ask her out if she has no feelings for him.

Ha-kyung seemingly refuses to be involved in a new workplace romance despite she and Shi-woo admitting their feelings for each other. After a massive pile-up due to radiation fog over the peninsula, Ha-kyung and Shi-woo get tangled in an awkward argument on how to issue their fog advisories. Yoo-jin writes a news article about the lack of an official fog advisory in KMA's system of weather advisories (기상특보 gisangteukbo), which she discussed without providing proper context and puts the KMA in a bad light. Ha-kyung and Shi-woo team up in crafting a feature refuting Yoo-jin's biased article.

Ki-jun finds it difficult to let go of Yu-jin's lie. Unrest grows within Ha-kyung's team, and Um Dong-han struggles to focus at work.

Ha-kyung grows wary of Si-woo's secrets after running into him at a motel. News about her mother sends her hurrying to the hospital.

After an uneasy convorsation with Yu-jin, Ki-jun seeks sage advice. While looking for a place to crash, Si-woo finds someone else in need of a home.

As temperatures boil over outside, so do emotions as another uncovered truth pushes the animosity between Si-woo and Ki-jun to new heights.

Ha-kyung narrates about the uncertainty of the weather forecasting, especially when it comes to the rainy season arriving. She does not want to take anything for granted. Bothered to no end by the sight of Ha-kyung and Si-woo together, Ki-jun tails them on their day-off. Meanwhile, Yu-jin wonders where he is. When Ki-jun finally makes it home, Yu-jin is annoyed because he missed his mother's birthday. The next day in office, there is still uncertainty regarding the rain at the weather station, so they need to report on the delay. Si-woo does not think they should make a hasty announcement, but Ki-jun challenges him. The chief director asks both men to debate their theories so they can publish an appropriate statement. Yu-jin interviews Ha-kyung one-on-one about the weather miscalculation, but brings up the rumors that she is dating Si-woo afterwards. She admits he is innocent, charming, smart, and good looking. Ha-kyung asks Yu-jin why she broke up with him if he is a good person. Yu-jin tells Ha-kyung that Si-woo does not believe in marriage. Meanwhile, Ki-jun tells Si-woo that Ha-kyung does not date anyone who does not consider marriage.

Ha-kyung faces intensifying pressure from her mother to get married. A pesky reporter lurks around the office in search of a good story. Eum notices that his daughter is on a field-trip to the KMA and excitedly catches up with her but Eom Dong-han's wife she is not impressed about Bo-mi going to the KMA. She wants him to tell their daughter not to go and to call off the whole event. When information about a heat spike has been mistakenly uploaded onto the online portal. Myung-joo is in charge of this and she profusely apologizes as they hurriedly work to take it down but Butcher Heo notices it flash up on the portal and inevitably starts writing up a story of his own. The next morning, the Director General is unhappy with news of the incorrect heat spike has become a public interest, as Yu-jin talks with Heo-in the cafeteria is terrible. packs up her things and decides she and Ki-Jun should take some time apart.

Ha-kyung sends Si-woo on an assignment to the Jeju island Typhoon Center. Si-woo clearly shows displeasures but then agrees with a smile. Meanwhile, Ki-jun tells Yu-jin not to leave for a "break" or it will be over between them. She sticks to her decision and leaves the apartment. Um Dong-han is happy to see his daughter Bo-mi at work while Um Dong-han's wife looks at a petition for a divorce. Later on, Bo-mi has an allergic reaction and collapses in the bathroom. She ends up at the hospital, and the wife berates Um Dong-han for giving their daughter processed meat at the cafeteria. Si-woo meets Ha-kyung, and she tells him they should try and make it work. However, the next day, Ha-kyung is devastated when she learns that Si-woo has left for Jeju island. Ha-kyung blames Ki-jun for these and believes if it was not for the wounds he created, she would not have sent Si-woo away.