New England Weather This Week: Drier

This week will certainly be a change in pace from last week as ridging and high pressure dominates to start the week. Some unsettled weather will enter the picture later in the week, but still nothing like last week.

MONDAY-WEDNESDAY

The beginning of this week will feature a Rex Block setup over the eastern United States. This occurs when an area of high pressure is located directly north of an area of low pressure. The high blocks the low from making a quick exit. In this case, New England is under the ridge of the high pressure with the low pressure system sitting over the South. This changes up the weather pattern from our previous block, which resulted in plenty of rain. This block will continue to bring New England dry and quiet weather.

Below: 500mb height anomaly showing a ridge built over southern Canada and the northeast with a trough over the southeast:

The pressure gradient will strengthen between the high and low on Monday. This will create a breezy southwest wind and allow temperatures to warm from the weekend. Surface high pressure over the Gulf of Maine and a backdoor cold front will create a decent temperature contrast on Tuesday. The coastal plain will likely get held to the 60s with the immediate coast remaining in the 50s. Inland areas will push well into the 70s to near 80°.

Below: Temperature departure from average Tuesday afternoon:

Wednesday will likely see clouds increasing from southwest to northeast during the day as the Rex Block breaks down. As this pattern breaks down, it will allow the low pressure system over the south to meander northward. Showers on Wednesday will be most likely over western New England with a majority of the region likely seeing a mainly dry day, at least until late in the day.

THURSDAY & FRIDAY

The Rex Block will likely fully collapse by Thursday, allowing for a period of large-scale, upper-level troughing to take hold across the northeast. The closed low pressure system over the Great Lakes will likely transition to more of an open wave as it crosses New England, meaning the system will not have a distinct center of circulation. This will allow for periods of scattered showers from Wednesday night through Friday.

With an open wave, forcing for showers will be weak while moisture increases. This means washout potential is low and extended periods of dry weather remain likely between the showers in any given location within New England. Humidity will be on the increase late this week as well, with dew points pushing into the 60s. This will provide some juice for the potential of thunderstorms Friday as instability also increases.

Temperatures will generally be in the 70s during this time with 60s along the coastal plain as an onshore continues. It will likely feel stickier during this time as humidity increases to its highest levels of the young season so far. With dew points climbing into the low to mid 60s, the afternoon may have a bit of a summer feel despite the lack of hot temperatures.

Below: GFS showing potential dew points Friday afternoon:

WEEKEND

The wave of low pressure passing New England Thursday and Friday will move east for the weekend. This will be replaced by an upper-low sliding eastward from the Great Lakes into southeast Canada. This will keep the chances for scattered showers and thunderstorms in the picture through the weekend.

As is the case for Thursday and Friday, washout potential remains low. Saturday could play out similar to Friday and Sunday will be dictated by the timing of the low pressure moving eastward. At this point, it's near impossible to time out when the highest shower chances will be late this week and into the weekend.

Below: Current weather map for Saturday (May 17):

BEYOND

Signs are pointing toward a cooler end to May relative to seasonal averages. After this upcoming weekend, there could be a sustained period of cooler weather across the northern United States as troughing continues to dominate. While exact temperatures are hard to say at this point, New England could see plenty of highs in the 50s and 60s through most of next week.