If you are like many others today, the fact September has arrived is a bit tough to grasp.  Meteorological summer is over and Labor Day weekend begins tomorrow.  There are lots of facts both climatological and astronomical I could write about September, but today it’s the fact September brings peak tropical activity that is most relevant.

Now we have an unofficial final weekend of summer and a hurricane named Hermine colliding in a way that will impact many of your  holiday plans.  There are still numerous questions about the  way this meteorological story will unfold, so it’s important to check the latest forecast throughout the weekend.  What I am writing about now is based on the best information at present, but this will change in another 12 hours.

The latest track of Tropical Storm Hermine from the National Hurricane Center

The latest track of Hurricane Hermine from the National Hurricane Center

First, Saturday and Sunday look to be the best days of the weekend because any impacts from Hermine won’t move in until Sunday night or even Monday if they do.  There may be some cloudiness showing up on Sunday afternoon along the southern tier of Maine, but there’s also a chance the clouds hold off until Sunday night.

Monday remains the day any impact would arrive in southern Maine.  If you are headed south this weekend expect more influence on the weather from the tropical storm including wind and rain across the mid-Atlantic.

Here our chances for rain showers will increase Sunday night into Monday, with Monday being the day when rain is most likely, but still not definite.  The most likely areas to see rain would be coastal York and Cumberland counties, with inland areas remaining dry.

The American Model has been bringing Hermine closest to Maine, but all models keep most of the rain and wind away from the area

The American Model has been bringing Hermine closest to Maine, but all models keep most of the rain and wind away from the area

The problem  and reason I can’t be more sure of the weather for Sunday and Monday is because of two meteorological variables.  The first is high pressure over northern Maine.  The strength and exact configuration of this system will help determine how far north the rain and wind will travel.  The second is the strength of Hermine itself.  The storm could weaken over the weekend and end up just spinning off the mid-Atlantic coast, never bringing us much rain at all.  It could also remain a bit stronger and move farther north bringing a windswept rainstorm to part of the state, but this is less likely.  No matter what happens, southern New England will see the worst weather Sunday and Monday.

On Friday, as the storm continues to develop and we get a better idea of how the steering current of the atmosphere will carry Hermine, the forecast for Sunday and Monday will become clearer.   At this point I think it’s a good idea to plan on at least a cloudy finish to the weekend with possible rain.  Remember, we desperately need rain and missing this opportunity would just allow the drought to grow even longer.  It’s ironic high pressure has been keeping us dry all summer and now it might once again keep us from receiving some beneficial rain.

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