Significant Weather Weekly Outlook Update
No hazardous weather is likely for southern New England through the holiday weekend. This message aims to discuss briefly yesterday’s (Wednesday’s) weather and provide an overview for the coming holiday weekend.
Wednesday Thunderstorms
Conditions appeared most ripe for potentially strong to severe thunderstorms yesterday afternoon and evening across CT, RI, and southeast MA due to an unstable air mass and approaching cold front. Showers and thunderstorms did finally move across that region yesterday mid to late evening with the heavier showers and embedded thunderstorms along the south coast. An upper-level trough and weak surface low pressure moved ENE along a sagging cold front late Wednesday and provided a focus for the showers and embedded thunderstorms across southern portions of southern New England last night. My suspicion is that subsidence (descending air) ahead of that upper-level trough may have inhibited thunderstorm development for a time Wednesday afternoon in spite of steep low level lapse rates. By the time the atmospheric environment became more favorable for convection, the daytime heating had been lost and the front had time to sag further south. That reduced the instability and risk of stronger thunderstorms. That upper-level trough and weak surface low pressure wave along the front were relatively subtle but still organized enough to modulate the location and timing of convective weather.
Memorial Day Weekend
Various numerical weather prediction models have come into better agreement for at least Friday through Sunday. Friday and Saturday look to be dry. Temperatures should be near normal for this time of year on Friday but likely below normal Saturday due to the combination of increasing clouds and onshore breezes. Essentially all models bring a wave of surface low pressure Saturday night from the mid-Atlantic region and along the front that had sagged a little south of New England (and may reverse course as a warm front that moves north to near our south coast). Although there are variations in model timing, it looks like fairly widespread rain of varying intensities Saturday night through most, if not all, Sunday as this system moves through. Memorial Day itself may feature drier weather but there’s considerable uncertainty. While some models dry southern New England out on Monday, others bring a secondary upper trough through our area with additional showers. For those with outdoor plans, suggest you check later forecasts from the National Weather Service (available at weather.gov/box for most of southern New England).
Next Message
Since hazardous weather does not appear likely this weekend, the next message will probably be the weekly significant weather outlook scheduled for Monday. I will include a discussion on the outlook for this coming hurricane season in that message. The National Oceanic and Atmospheric Administration (NOAA) issued its seasonal hurricane activity outlook today. The NOAA outlook (like outlooks from other entities including Colorado State University that initiated such projections many years ago), notes that El Nino conditions may suppress hurricane activity to some extent due to increased vertical wind shear from a subtropical upper-level jet. Will discuss further in the coming Monday’s weekly significant weather outlook.
About this Blog and Disclaimer
The National Weather Service monitors the weather 24/7 and updates forecasts, watches, and warnings as necessary. For most of southern New England, refer to your local Weather Forecast Office for the latest forecast/warning information at weather.gov/box. For information from other Weather Forecast Offices, go to weather.gov and click on the location of interest on the map.
The frequency of this blog will depend upon the nature of the weather threat and availability of the author. Thus, for the latest information on weather forecasts and warnings, refer to the National Weather Service, which monitors and forecasts the weather 24/7.
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The BHOSC maintains a continuous daily observation record that dates from February 1, 1885 without interruption and provides educational information on weather and climate to area students and the community at large. Your support of BHOSC is much appreciated and enables this nonprofit organization to maintain the long-term climate record at the Blue Hill Observatory (longest continuous record in North America) and provide valuable educational resources on weather and climate via outreach to schools, site visits/tours, webinars, and conferences. For more information on the Blue Hill Observatory and Science Center, explore bluehill.org.
Message issued May 21, 2026 by:
Bob Thompson
Retired National Weather Service Meteorologist
Blue Hill Observatory and Science Center Board member
