...A STATISTICAL PREVIEW OF CARIBOU'S MAY WEATHER...

During the month of May the average high temperature climbs from 56 degrees on the 1^st to 68 by the end of the month.  The average low temperature rises from 36 degrees on the 1^st to 45 by the end of the month.

The warmest temperature ever observed during the month of May was 96 degrees on May 22, 1977.  The coldest temperature ever observed in May was 18 degrees on may 2, 1974. The high of 96 tied with June 29, 1944 for the all-time warmest temperature ever observed at Caribou since weather records began in 1939.   

Measurable snowfall (0.1” or greater) is observed on average of once every 3 years during the month of May.  A trace of snow is observed on average of about 75 percent of the time during the month of May…so seeing a few flakes of wet snow in May is by no means an unusual event.  A snowfall of an inch or more has occurred 4 times (1981-2010) during the month of May.  The greatest calendar day snowfall of 5.8 inches was observed on May 8, 1967.

The average date of the last freeze is May 15^th.  Since 1940 the earliest date of the last freeze was April 27, 1989.  The latest date of the last freeze was June 12, 1950.  Typically there will be the threat of at least a light frost until around Memorial Day. 

Thunderstorms become an increasing threat during the month of May with an average of 2 days when a thunderstorm is observed at the airport in Caribou.  Severe weather also becomes an increasing threat with severe thunderstorms observed somewhere across northern Maine about every other year during the month of may. 

The outlook from the Climate Prediction Center for May indicates that there are no strong climate signals that point toward an unusually warm or cool month.  There are also no strong climate signals that point toward it being an unusually wet or dry month.