A Look Ahead to the Upcoming Spring and Summer Months

 The beginning of April started strong with temperatures actually sitting above average and it wasn't until the middle, the 14th to be exact, that we fell below and remained there.  So just what does the rest of spring and summer look like in terms of temperatures?

At least for the beginning of the last week of April it appears as if temperatures will sit slighty above average with the upper 60s in the forecast for Monday and Tuesday before falling back into the low 60s towards the middle of the week.  A strong jet streak (stronger winds within the jetstream) will push into the Pacific Northwest later this weekend.  What that will do is help develop a trough in the western parts of the U.S. while a ridge builds across the eastern Great Lakes and East Coast.  This will also increase our chances for above average precipitation during that period as we'll be pulling a little more moisture in from the Gulf of Mexico with each system that passes.  Those warmer temperatures, unfortunately, appear to be short-lived as we look into May, June and possibly July.

Looking over the next couple of months I feel as if the remainder of spring and even the beginning of summer will fall below average in terms of temperatures.  La Nina was in full force during the winter of 2010-2011.  We are slowly starting to see temperatures around the equator in the Pacific warm which would indicate a return to ENSO (El Nino Southern Oscillation) neutral conditions by June.  Another indicating factor that makes be believe we may be running a little on the cooler side is when looking at the forecast NAO (North Atlantic Oscillation) and AO (Arctic Oscillation) they fall negative by the beginning of May.  The AO is a difference in air pressure between the Arctic and the mid-latitudes.  When the AO is positve, air pressure over the Arctic is low and pressure over the mid-latitudes is high.  The prevailing winds keep extremely cold air in the Arctic.  But when the AO is negative the pressure gradient weakens.  The air pressure over the Arctic is not as low and not as high in the mid-latitudes.  This enables Arctic air to slip south and warm air to move north.  The same thinking can be applied to the NAO.  When I see both of them turn negative towards the first of May it makes me think we will have some cooler days awaiting us.

As far as the rest of spring and summer look a lot of the climate models have either ENSO neutral or even cool conditions for May, June and July and then either staying neutral or warming (which could be a sign of El Nino returning) by August, September and October.  With that, my gut wants to tell me that overall we will likely see a cool spring and summer and could hold off on the heat until the end of summer and even early fall.  Now I don't think that every single day during that time frame will be cool.  We will probably see our fair share of heat and even severe weather.  Chief Meteorologist Ty Shesky brought up a valid point that there could be other factors that will influence our weather locally.  He noted that we should keep an eye on the drought situation developing in the southern Plains because a drier soil and strong southwest flow would allow temperatures to warm closer to home.  However, we might not see many times when the flow is from the southwest if the jetstream does in fact reside to our south.  It will be interesting to see how the next couple of months pan out and see if my prediction does in fact hold some truth.