The big question that comes up this time of year is whether we will have a hot or cool summer, which is more a question of climate forecasting than weather forecasting. That said, I always like to give climate forecasting a shot. My winter forecast of colder than normal with above normal ice and snow did pretty well. Here’s my take on the upcoming summer–
Three things stand out this summer- the beginning of an El Niño Pacific cycle, the beginning decline in the solar maximum (whose peak sunspot number been lower than several previous cycles), and the continued tendency of the jet stream to dip down as it has been doing for the past 10 months.
The El Niño usually results in wetter conditions for our area and the low solar maximum combined with the continued jet stream dip tendency suggests cooler than average temperatures.
This doesn’t mean that we won’t get hot periods during the summer; that’s what summer is all about. But the my general feeling is that this summer may be cooler than average with above normal precipitation.
Last night’s showers that interrupted the Phillies game were forecast to occur, but the chances were low probability. Low probability clearly doesn’t mean no probability. The showers were the result of an upper air cyclonic flow and a cool pool of cold air aloft, resulting in instability and lift.
Today’s NAM model continues with the possibility of instability showers developing between 2 PM and 7PM. —- expected to be widely scattered and somewhat more numerous in central NJ.
In fact, the NAM lifted index is forecast to be somewhat more unstable today, so scattered showers are likely, although not every area will see them.
The non-meteorological start of the summer season begins this weekend, and by Monday, it should feel like summer. A lingering reminder of the spring is still with us in the form of an upper air cyclonic flow, and this upper air feature will move away by Sunday.
Before then, the pool of cold air in the upper atmosphere may cause instability showers to form Saturday afternoon, although the models keep the higher likelihood to our north.
Beautiful weather– plenty of sunshine– for Sunday and Monday.
A warm front will move through this evening, with showers and perhaps a thunderstorm.
Milder temperatures and higher dew points follow. A generally unstable pattern through Saturday as a developing upper air trough allows instability showers especially Saturday afternoon. Things should dry out on Sunday, but the upper air trough may allow clouds to form Sunday afternoon.