Labor Day weather across northern and eastern Maine has varied significantly over the years.  The holiday is celebrated on the first Monday in September, and can thus occur from the 1^st through the 7^th of September.   Normal high temperatures at Caribou (Bangor) drop from 71F (75F) on the 1^st to 69F (73F) by the 7^th.  Normal low temperatures are in the upper 40s at Caribou and low 50s at Bangor.

The warmest temperature ever observed during the first week of September at Caribou is 92F, which was observed on September 1, 2010.  The coolest temperature ever observed was 30F, which was observed on September 3, 1976.  There have been a number of days throughout the years when the high temperature has failed to get out of the 50s during the first week of September.  On September 6, 1948, the high was only 48F. The wettest day ever observed during the first week of September was September 6, 1979, when 3.08” of rain fell.

At Bangor, the warmest temperature ever observed during the first week of September was 99F, on September 7, 1945.  The coolest temperature ever observed was 33F, on September 6, 2000, and also on September 7, 1942.  There have been a number of days throughout the years when the high temperature has failed to get out of the 50s during the first week of September. The wettest day ever observed during the first week of September was September 4, 2010 when 3.31” of rain fell.