Long Range Weather Forecast (June 2012)

(Blog Written by Donald Sutherland)

June 2012 Forecast:

Although past transitions to possible El Niño conditions have witnessed a chilly summer, it appears that the current transition will witness at least the first month of summer turning out warmer than normal across much of North America.

Key Assumptions:
• Neutral ENSO conditions are likely to prevail through much or all of June
• The AO will likely be near neutral (with variability in negative and positive ranges)
• The PNA will likely be predominantly positive (but generally < +1)

The top analog was 1969. Both 1953 and 2009 were close behind.

The charts on which my June idea is based are:

Left: Composite temperature anomalies based on ENSO/Teleconnection Analogs.
Right: Observed Decadal Temperature Change for June

Posted Image

Some of the greatest warm anomalies in the East occurred during the 6/20-30 timeframe, especially in 1953 and 1969. The leading analogs do not clarify the ENSO situation going foward, but they maintain the theme that odds lean toward the develop of an El Niño. 1953 saw neutral ENSO conditions. 1969 and 2009 witnessed the onset of El Niño conditions.

Based on the combination of the composite teleconnection analogs, observed notable warmth in the Arctic region, and the observed decadal temperature changes, my thoughts for June are as follows:

Much of North America will likely be warmer than normal. A portion of northern Canada could be near to somewhat above normal. Part of the West Coast, probably somewhere in California to perhaps the Pacific Northwest could be cooler than normal.