diff --git a/R/LogisticReg.R b/R/LogisticReg.R
index 439a38bafec162d6cba34b664204269d8679baa9..c0d914abd45843b6b23a41dae76b38371635a7ba 100644
--- a/R/LogisticReg.R
+++ b/R/LogisticReg.R
@@ -680,8 +680,12 @@ LogisticReg <- function(exp, obs, exp_cor = NULL, exp_lats, exp_lons, obs_lats,
    for (j in 1:length(lm1)) {
     window <- ((j-1)*k_out+1):((j-1)*k_out + k_out) # test the daily data of the corresponding year
     if (any(apply(df[window, ], 2, function (x) all(is.na (x))))) {
-      pred_vals_ls[[j]] <- array(rep(NA, length(window) * (length(probs_cat) + 1)), 
-                                    dim = c(length(window), length(probs_cat) + 1))
+      if( length(probs_cat) + 1 == 2) {
+        pred_vals_ls[[j]] <- rep(NA, length(window) ) 
+      } else {
+        pred_vals_ls[[j]] <- array(rep(NA, length(window) * (length(probs_cat) + 1)),
+                                       dim = c(length(window), length(probs_cat) + 1))
+      }
     } else {
       pred_vals_ls[[j]] <- predict(lm1[[j]], df[window,], type = "probs") 
      }