diff --git a/tests/testthat/_snaps/date-atus.md b/tests/testthat/_snaps/date-atus.md
index e817980..f991266 100644
--- a/tests/testthat/_snaps/date-atus.md
+++ b/tests/testthat/_snaps/date-atus.md
@@ -154,3 +154,25 @@
         <int> <date>     <date>   <dbl>
       1  2019 1972-01-01 NA          NA
 
+# date_atus picks correct day to exceed 20
+
+    Code
+      date_atus
+    Output
+      # A tibble: 1 x 4
+      # Groups:   year [1]
+         year start_date end_date    atus
+        <int> <date>     <date>     <dbl>
+      1  2019 1972-01-01 1972-01-02    20
+
+# date_atus picks correct day to exceed 600
+
+    Code
+      date_atus
+    Output
+      # A tibble: 1 x 4
+      # Groups:   year [1]
+         year start_date end_date    atus
+        <int> <date>     <date>     <dbl>
+      1  2019 1972-01-01 1972-01-31   600
+
diff --git a/tests/testthat/test-date-atus.R b/tests/testthat/test-date-atus.R
index 2b78645..09dad3f 100644
--- a/tests/testthat/test-date-atus.R
+++ b/tests/testthat/test-date-atus.R
@@ -117,3 +117,33 @@ test_that("date_atus NA if not enough data to reach", {
     date_atus
   })
 })
+
+test_that("date_atus picks correct day to exceed 20", {
+  data <- tibble::tibble(
+    date = seq.Date(
+      from = as.Date("2019-01-01"),
+      to = as.Date("2019-12-31"),
+      by = "day"),
+    temperature = c(0, rep(20, 364)))
+  
+  date_atus <- date_atus(data, start_date = as.Date("2019-01-01"), atu = 20)
+  
+  expect_snapshot({
+    date_atus
+  })
+})
+
+test_that("date_atus picks correct day to exceed 600", {
+  data <- tibble::tibble(
+    date = seq.Date(
+      from = as.Date("2019-01-01"),
+      to = as.Date("2019-12-31"),
+      by = "day"),
+    temperature = c(0, rep(20, 364)))
+  
+  date_atus <- date_atus(data, start_date = as.Date("2019-01-01"), atu = 600)
+  
+  expect_snapshot({
+    date_atus
+  })
+})