Weather for New England and the Northeast

Area Forecast Discussion
National Weather Service Boston/Norton MA
245 PM EDT Sat Apr 18 2026

Synopsis
A cold front will cross the region Sunday, bringing widespread precipitation and a sharp drop in temperatures. High pressure builds in for the start of the work week, keeping things dry but unseasonably cool. A brief return to typical spring temperatures occurs Wednesday before another front cools us down for the end of the week.

What has Changed
Splashover to minor coastal flooding is now considered possible around the midnight high tide cycle for eastern coastal Massachusetts. Also, the gusts associated with the cold front will bring marginal small craft conditions to the southern waters. Otherwise, the forecast has not deviated from the previous discussion.

Key Messages
Nuisance coastal flooding, mainly splashover is possible tonight around the midnight high tide cycle for east coast of Massachusetts, including the island of Nantucket.

Steady rain arrives Sunday with the passage of a cold front and a period of breezy northwest winds. Turning much colder Sunday night.

Cooler than normal Monday. While generally dry weather is expected, a weak area of low pressure could bring clouds and scattered showers.

Seasonable temperatures Wednesday, though another cold front arrives and temperatures fall once more for the second half of the week.

Discussion
Key Message 1
Nuisance coastal flooding, mainly splashover is possible tonight around the midnight high tide cycle for east coast of Massachusetts, including the island of Nantucket.

Guidance this morning continues to point towards very minor coastal flooding for eastern Massachusetts and Nantucket during the overnight high tide cycle around midnight. The combination of onshore flow, which is wind blowing from the ocean toward the land, and the astronomical tides could lead to splashover to minor coastal flooding for most vulnerable low lying locations. As a result, the office has issued a Coastal Flood Statement. Please avoid any prone area and never drive through standing water.

Key Message 2
Steady rain arrives Sunday with the passage of a cold front and a period of breezy northwest winds. Turning much colder Sunday night.

The rest of Saturday and tonight should remain dry, however, a bank of stratus, which are low level flat clouds, off the coast will move onshore tonight. Expect low clouds and a few areas of drizzle, mainly across eastern Southern New England, through Sunday morning, in addition to areas of locally dense fog across eastern Massachusetts.
As for the rest of Sunday, expecting a raw and chilly day. In fact, high temperatures in the low to mid 50s degrees occur during the late morning, as a strong cold front will move through and send temperatures falling shortly thereafter.

This cold front brings widespread precipitation and a few rumbles of thunder with limited instability. Precipitation rates are moderate to heavy with PWATs, or Precipitable Water values which measure the total moisture available in the atmosphere, between 1.2 to 1.4 inches. Precipitation amounts are in the neighborhood of 0.25 to 0.50 inches with lower totals along and east of I-95.
Any convective showers, which are more intense bursts of rain caused by rising air, have potential for heavier precipitation. We cannot discount the HREF (High Resolution Ensemble Forecast) which shows potential for localized values above an inch. With much colder air advecting, or moving horizontally, into the region, snow showers remain possible for the highest terrain of western Massachusetts.
Do not expect any impacts, but a light coating on elevated surfaces remains possible. Associated with the cold front is a brisk northwest wind with gusts of 20 to 30 MPH late morning and early afternoon, which will lead to an overall raw and chilly feeling.
Clearing Sunday night with easing winds, temperatures fall into the low to mid 30s degrees, while the higher terrain of northern Worcester County and northwest Massachusetts dip into the upper 20s degrees.

Key Message 3
Cooler than normal Monday. While generally dry weather is expected, a weak area of low pressure could bring clouds and scattered showers.

The upper level trough, an elongated area of low atmospheric pressure, settles overhead Monday, and with it, unseasonably cold air moves in during CAA (Cold Air Advection, which is the movement of colder air into a warmer region). Temperatures at the 925 mb level, roughly 2,500 feet above the ground, fall below 32 degrees and may even dip to 23 degrees by Monday morning. Breezy west to northwest winds continue, and highs may not climb out of the upper 40s and low 50s degrees Monday afternoon.
These winds will start to diminish as high pressure approaches from the west, and lows Monday night may fall into the 20s degrees for much of southern New England.
Even with approaching high pressure, more guidance has started to latch onto a weak low pressure moving into the region Monday that could bring increased clouds and scattered showers. Ensemble members and deterministic models, which are individual computer simulations used to predict weather patterns, from different guidance suites have started to indicate some showers Monday as a result of this weak low, though confidence in this feature developing is still relatively low.
Outside of this, incoming high pressure should keep the region dry for much of the start of the week before it exits heading into Wednesday.

Key Message 4
Seasonable temperatures Wednesday, though another cold front arrives and temperatures fall once more for the second half of the week.

Some showers are a possibility once again heading into Wednesday morning as another shortwave, or a smaller scale weather disturbance, approaches, but more seasonable temperatures make a return as the trough early in the week exits.
Temperatures aloft recover to around 41 degrees with southwest flow returning, supporting more seasonable highs in the upper 50s to low 60s degrees.
Northwest flow makes a return towards Thursday and Friday in the wake of another front passing through sometime late Wednesday, and high pressure builds back in as ridging, an area of high pressure, approaches, which should keep the region dry yet chilly.