A recap of June and a look ahead to July…

Posted by Danielle Niles July 2, 2009 at 7:11 am

I think many of us can agree that the past month was not ideal in terms of the weather – unless ofcourse you like unseasonably cool temperatures and wet conditions. But with June officially behind us now, the hope is for warmer and brighter days for July. Unfortunately, today isn’t showing much promise in respect to making some improvements. While there will be some peeks of sunshine here and there today, this just adds “fuel to the fire” so to speak in regards to thunderstorm development. We’ve already been tracking showers and thunderstorms early this morning across parts of southern New England, and trend this afternoon will be for more thunderstorms to develop from south to north.

Tomorrow, we finally get rid of the east wind that has been plaguing us for days. Winds will shift out of the southwest and temperatures will be several degrees warmer than they have been (but still running below average). The threat for showers and thunderstorms will continue though, especially in the afternoon. The good news? The holiday weekend shows signs of improvement…

First let’s start off with a mini recap of the month of June. The graphic to the left shows a comparison between the normal amount of rainfall for the month of June and the actual amount received for this past month for a few locations across New England. Your eye is immediately drawn to the fact that we were several inches above the average for the month of June with the exception of Boston (which tied the average).

And it was not only a rainy month of June, but a cloudy one too. So if you’ve felt a little deprived of vitamin D, the gloomy weather may have played a role in that. Both Boston and Providence had not a single mostly sunny day during the entire month of June. Party sunny days, sure…but no days where the average cloud cover was 30% or less. The image to the left shows the percentage of mostly sunny days for the months of May and June combined (it was just too sad doing June alone). In any case, the results still show the fact that it’s been a bit of a dismal stretch here.

So what lies ahead for the month of July then? The Climate Prediction Center (CPC) releases a monthly outlook at the start of every month for a long range look at the precipitation and temperature forecast. A large scale trough (or dip) in the jetstream is forecast to position itself over the eastern half of the United States (pretty similar to the month of June). Now, the jet stream does a couple of different things: it aids in steering storms, and also acts like a thermostat. So with the jetstream positioned close by, storms will be likely to take tracks close to New England, meaning above normal precipitation amounts. New England will also be positioned on the northern side of the jetstream, which is the cooler side, meaning below average temperatures.

Keep in mind that it’s hard enough to predict the weather for the next several days, let alone a month in advance, and forecast accuracy tends to decrease with time. One has to wonder whether or not this weather will actually hold for another month. If we can get a slight shift in the upper level pattern than it could be a whole different ball game.