[Solved] How to calculate a condition using dplyr?

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As I understand it, you want a column that checks if the temperature deviates by 5 – 6 degrees (if the temp is greater than 10) and another column to check if it is differs by 7 degrees or more.

The current code you are using seems to identify the coldwave values correctly, although is including the severe_coldwave values as well.

You could add another check for the severe weather, similar to what is already coded, and set any is_coldwave values to FALSE if the weather is severe.

This will set values that deviate from 5-6.5 degrees to is_coldwave and more than 6.5 to is_severe_coldwave

df_out <- df %>%
  as_tibble() %>% # for easier viewing 
  mutate(day = format(as.Date(df$Date, format="%Y-%m-%d"), format="%m-%d")) %>%
  tidyr::pivot_longer(cols = -c(Date, day), 
                      names_to = "Stations", values_to = "MinT") %>%
  left_join(df_summarise_all %>% rename(mean_MinT = value), 
            by = c('day' = 'day', 'Stations' = 'variable')) %>%
  mutate(is_coldwave = MinT < ifelse(mean_MinT < 10, mean_MinT - 4, mean_MinT - 5))%>%
  mutate(is_severe_coldwave = MinT <= ifelse(mean_MinT < 10, mean_MinT - 5.5, mean_MinT - 6.5 ##values differing by 7 or more are is_severe_coldwave
                                              )) %>% 
  mutate(is_coldwave= ifelse(is_severe_coldwave == T, F, is_coldwave))  ##values labeled is_coldwave and is_severe_coldwave updated so that is_coldwave = F

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solved How to calculate a condition using dplyr?