Boston Climate: Cooler March-May=Higher Risk of Cool Summer

[donsutherland1]

Based on historic patterns pertaining to the temperatures in March through May, in general, the cooler March through May is, the more likely a cooler than normal summer lies ahead.

A rough risk assessment is as follows from the historical data:

<b>Risk of a cooler than normal summer:</b>

MAM Mean: 48.5° or above: Low to Moderate
MAM Mean: 47.0° to 48.4°: Moderate
MAM Mean: Below 47°: High
MAM Mean: Below 45°: Extremely High

Here's how the last 15 Years (1989-2003) fared:

MAM Mean: 48.5° to 49.9°: 2/6 summers were cooler than normal
MAM Mean: 47.0° to 48.4°: 3/6 summers were cooler than normal
MAM Mean: Below 47°: 3/3 summers were cooler than normal

<b>Note: </b>MAM=March-April-May

At this point, assuming May finishes 1° or above normal--something that I expect--Boston would have a mean temperature of 48.5° or above for the March through May period.

At this time, I continue to believe Washington, DC through Boston will see a warmer than normal but not extreme summer.