Weather

Cool Pattern Returns For A While

There are numerous showers with some embedded downpours this morning over central Maine as a storm system over southern Canada moves slowly north. In southern New England, generally clear skies were ushered in behind this same system as the showers here ended during the overnight.

Our weather pattern has changed and what’s old is new again. We are in many ways back to the pattern we saw last month, with a cool core of air in the northeast section of the country. Remember, March also was a fairly dry month due to the flow from Canada.

Now, it is a week away from May and the sun is as strong as it would be during August. It’s virtually impossible to have highs in the 20s as we did for much of March. That said, it can remain chillier than you might like, mostly in the 50s to perhaps near 60 at times over the next 7 to 10 days.

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The map below, which shows temperatures May 1, clearly indicated how the coolest air is going to be here in the east. Map after map I looked at this morning continues this pattern of cooler-than-average temperatures.

cool in the east.png

Morning lows will reach the 30s to lower 40s during this period and there will be some frost and even freezes in places. This could be an issue with some growers of fruit trees if the blossoms open and those places reach 28 degrees or lower.

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I was walking earlier this morning and noticed a few apple blossoms had popped open.

Meteorology Of The Clouds and Possible Showers

The air is somewhat unstable today. This term means clouds and even showers can form due to the heating of the ground. What happens scientifically is the ground becomes warm quickly this time of year, and then the air is heated just above it. This warm air then rises into the cool air above and eventually, if it gets high enough, forms clouds and sometimes showers. It’s basically like a little hot-air balloon surrounded by cool air. The bigger the difference between the air temperature at the ground and the air temperature at say 10,000 and 18,000 feet, the greater the potential for clouds, showers, or even thunderstorms. If the air rising is cooler than the surrounding air, it’s stable and clouds are hard to come by.

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Today there is little question the clouds will pop up quickly later this morning. There could be a shower, but northern areas are most at risk.

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I’ll be updating the weekend forecast here and on Twitter. Please follow me there.

I don’t foresee any major rain storms during this period as the flow from the northwest will prevent any significant amounts of moisture from making into the New England.
The weekend is looking nice for outdoor activities in April, but it will be on the cool side of average. I can’t totally rule out a shower in the middle of the day Saturday, but if you do get one it won’t last very long.

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