weather_comp.R

library(tidyverse)
library(lubridate)
library(weathercan)

# Lethbridge and Saskatoon
data <- weather_dl(station_ids = c(2265, 50091), 
                   start = "2012-01-01", end = "2018-08-15")

# Plot full data
data %>%
  ggplot(aes(x = time, y = temp, group = station_name, 
             colour = station_name)) +
  theme_bw() + 
  geom_line()

# Plot mid-September to mid-October from multiple years
data %>%
  filter(month %in% c("09", "10")) %>% 
  mutate(time = ymd_hm(paste0("2018-", strftime(time, format = "%m-%d %H-%M")))) %>% 
  filter(time >= ymd("20180915"), time <= ymd("20181015")) %>% 
  mutate(grp = paste0(station_name, year)) %>% 
  mutate(snow = str_detect(weather, "(s|S)now"),
         snow = if_else(is.na(snow), FALSE, snow),
         snow = factor(as.numeric(snow))) %>% 
  ggplot(aes(x = time, y = temp)) +
  theme_bw() + 
  geom_line(aes(group = grp, colour = station_name)) +
  theme(legend.position = 'top') +
  geom_point(aes(size = snow)) +
  scale_size_manual(values = c(0, 2))