DAYS 1-5 (APRIL 10-14)

I’m not sure if you’ve been keeping track, but this is going to be the 5th consecutive “nice weather” Saturday. Two caveats to start the day though: 1) Low level moisture is causing some fog and low clouds near the South Coast which may take some time to break and dissipate. 2) A band of cloudiness from mid level moisture is rolling across eastern MA and south central NH as of 7:45 a.m. and has even had a few sprinkles of rain falling from it. This band of clouds will thin and break with time, but other patches of clouds will be around today, so don’t expect 100% sun. Despite that, it’s going to be even warmer today in some areas I anticipated would be cooler (eastern coastal areas, for example). You can thank the break-down, or weakening, of an “omega block” that has been responsible for several days of really nice spring weather here (though it has down sides: high pollen count, high fire danger, and lowering water supply). Today, everybody gets into a southwesterly air flow a little stronger than I had previously expected as high pressure sinks to the south, so other than the cooling influence in coastal areas where a southwest wind travels over water first, it’s going to be a rather warm day for mid April, with many areas reaching or exceeding 70. Enjoy it if you can, but don’t get used to it! One of our famed “back-door” cold fronts is on the way, and will charge across the region from northeast to southwest during the early hours of Sunday, introducing a northeast to east wind and much cooler marine air, complete with low clouds and eventually areas of fog and drizzle. Some areas that are in the lower 70s this afternoon will find themselves around 25 degrees cooler, in the upper 40s tomorrow afternoon. While this is going on regionally, the larger scale pattern shift will allow low pressure that has been stuck to our west to finally move eastward, kind of. It’s not going to charge in here because it’s still being met with resistance from the high pressure ridge that is moving slowly to the east off the East Coast, and the trough’s surface low will be trying to send lobes of moisture eastward that run into dry air. One such lobe will bring an area of rain into the region on Sunday, but as it advances in it will also be falling apart, so while some areas may see rain from it, other areas may not see a drop from that and are more likely to get wet from the drizzle caused by the air flow from the ocean. Either way, plan on Sunday being far different weatherwise than today is, which is certainly the pick of the weekend for outdoor activity! Looking ahead to the first part of next week, back to more of springtime reality for the Northeast as a large upper low, once the western portion of the omega block, swirls over and just south of the region. While this low is not loaded with moisture, it is likely to keep us on the cooler and somewhat cloudier side for several days. Unfortunately it does not look like it will generate much in the way of rainfall, which we could use.

TODAY: Fog/stratus South Coast into mid morning, variable clouds elsewhere with a possible sprinkle of rain eastern MA into mid morning. Sun/cloud mix midday-afternoon. Highs 58-65 South Coast, 66-73 elsewhere. Wind SW 5-15 MPH.

TONIGHT: Increasing clouds. Lows 45-52. Wind SW up to 10 MPH shifting to NE 5-15 MPH overnight.

SUNDAY: Cloudy. Areas of fog and drizzle. Chance of light rain in the afternoon. Temperatures generally steady 45-52. Wind NE to E 5-15 MPH.

SUNDAY NIGHT: Cloudy. Periods of rain possible. Areas of fog and drizzle. Lows 40-47. Wind NE to E 5-15 MPH.

MONDAY: Mostly cloudy. Areas of fog and drizzle. Periods of rain possible. Highs 47-54, coolest coastal areas. Wind E 5-15 MPH.

MONDAY NIGHT: Mostly cloudy. Lows 40-47. Wind NE up to 10 MPH.

TUESDAY: Partly sunny. Highs 48-55. Wind NE to N 5-15 MPH.

TUESDAY NIGHT: Mostly cloudy. Lows 39-46. Wind N up to 10 MPH.

WEDNESDAY: Partly sunny. Highs 50-57. Wind N 5-15 MPH.

DAYS 6-10 (APRIL 15-19)

Upper level pattern crawls eastward, starting out with low pressure near and just east of the region and our region in a coolish and slightly unsettled pattern. Eventually ridging pushes eastward and we may warm up (still cooler coast) by the end of the period. No significant precipitation in sight.

DAYS 11-15 (APRIL 20-24)

I’m not crazy about the medium range guidance timing of large scale features. Based on this my current idea is to slow everything down from what is shown on guidance. This would keep us mostly dry into late April finally with a rain chance increasing later in the period. Low confidence on this outlook.