Here we go again. Another couple of very cool days, featuring clouds and rain. Interestingly, June 2015 also started on a very cool note, with the first couple of days not reaching 50 at Logan International Airport. That month ended up being very wet, with about 5 inches of rain. Indeed, if you are looking for sunshine and warm weather, June can disappoint.
You can thank (or curse) the jet stream for this wet and cool pattern. This flow of air at about 30,000 feet continues to take a big dip over New England and when this happens the weather turns foul.
Storms, also known as low pressure systems, rotate counter-clockwise and often bring clouds and showers. Watch the loop below a couple of times. Notice that swirl in the atmosphere heading for the Great Lakes? That is a piece of upper-level energy that will help to keep that dip — meteorologists call it a trough — in the jet stream in place over the Northeast. These energy packets also help to ignite additional rainfall areas as they move through the upper-level flow.
Monday morning one area of showers brought about a quarter-inch of rainfall to the area. A new area of rain will fall overnight and early Tuesday. The forecast radar loop below has some areas of red and orange that indicate possible thunderstorms embedded within heavier showers. This means at least another half-inch of rainfall, perhaps even an inch and a half in some areas.
As this next system becomes stronger, it will allow winds to increase off the ocean. Winds may be strong enough for a few scattered tree branches to come down, and that can always lead to power issues. The other result of the marine air will be very cool temperatures. The coldest June 6 on record in Boston is 52 degrees. Highs Tuesday will be around this number.
When does it end?
Focus on the radar loop one more time. See how, in the beginning, (date is on top) the rainfall is rotating around over Southern New England? Notice how, by the end of the loop, the rain is moving south. This is the beginning of the end of this pattern. As high pressure builds in from Canada, it will push the clouds and showers south and east. The clearing will be slow at first, with only a few breaks in the clouds Wednesday along the coast. By Thursday and into the weekend, temperatures will recover closer to seasonal averages. I can’t rule out a shower sometime early in the weekend as the air becomes warmer, but after Wednesday morning the trend is much drier.
Next week: The warmth returns
While shutting down the shower activity will make many of you happy, I know a bit of warmth would also be appreciated. All the models agree next week is going to be significantly warmer. Some models have 80s and even 90s arriving here, but even the least warm of the models has upper 70s and lower 80s. This will occur with mainly sunny skies