textproduct: Boston / Norton

WHAT HAS CHANGED

No significant changes to the forecast.

KEY MESSAGES

- More seasonable temperatures, dry weather and comfortable humidities through tonight. Scattered pop-up showers across far western New England later Wednesday afternoon.

- High astronomical tides with less than a foot of storm surge could cause minor coastal flooding for the late evening high tides tonight.

- Gusty southerly winds with some showers and perhaps a few thunderstorms Thursday. Watching the severe weather potential too, but right now thinking main threat will be to our southwest.

- Beautiful stretch of weather Friday through Monday with warm afternoons and comfortable humidity.

DISCUSSION

KEY MESSAGE 1...More seasonable temperatures, dry weather and comfortable humidities through tonight. Scattered pop-up showers across far western New England later Wednesday afternoon.

Southern New england remains stuck between a nearly stationary low pressure across Nova Scotia and a weak high pressure across the central Appalachians. This will maintain a weak northwest to west flow across our region, except for local sea breezes late this morning into this evening. Thinking this should be a slightly later start to the seabreeze than is typical, more like early afternoon than mid morning. A more robust south wind is expected for Wednesday. Still thinking most of the day remains dry, but cannot dismiss the idea of a few pop-up afternoon showers across western MA. Not looking like much instability given the relatively lower surface dewpoints and high temperatures mainly in the 70s. Will need to monitor this over the next day.

KEY MESSAGE 2...High astronomical tides with less than a foot of storm surge could cause minor coastal flooding for the late evening high tides tonight.

Mostly splashover with minor coastal flooding observed with the late evening high tide. The higher of two diurnal high tides will remain the late evening one. Expecting overall tide heights to slow decrease over the course of this week. With the expectation for more localized minor coastal flooding, opted to continue the Coastal Flood Statements instead of Coastal Flood Advisories. That said, have the greatest concern for the typical spots like Morrissey Blvd. Low lying areas around Nantucket have also had some issues the past few high tide cycles. It's possible an Advisory may be needed here for another tide cycle, but will let later shifts evaluate further.

KEY MESSAGE 3...Gusty southerly winds with some showers and perhaps a few thunderstorms Thursday. Watching the severe weather potential too, but right now thinking main threat will be to our southwest.

Low pressure tracking northeast across Quebec will allow a pre- frontal trough/cold front to approach our region from the west on Thursday. Ahead of these features, a modest southwest LLJ of 45 to 55 knots will develop. This coupled with mixing will result in gusty southerly winds of 25 to 35 mph developing. High temperatures probably top out in the upper 70s to the middle 80s for most locales.

We do expect some showers to impact the region very late Wed night into the first half of Thu morning with a warm front crossing the region. Then we may see another round of scattered showers and perhaps a few t-storms Thu afternoon/evening with the actual cold front/shortwave. We will need to watch the risk for severe weather too given strong wind fields. But right now thinking that the main risk for this looks to be to our southwest where better instability resides.

KEY MESSAGE 4...Beautiful stretch of weather Friday through Monday with warm afternoons and comfortable humidity.

Two closed upper level lows just south of Hudsons Bay will result in height fields lower than normal Friday into this weekend across the Northeast. This will suppress deeper moisture to our south and result in a beautiful stretch of weather. High temperatures will generally be between 75 and 85 with comfortable humidity. Overnight low temperatures will mainly be in the 50s to the lower 60s.

Generally dry weather is on tap over this time period too. Some northern stream energy may result in a few brief diurnally driven spot showers, but for the most part dry weather is expected.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

Forecaster Confidence Levels...

Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent.

Today...High confidence.

VFR. NW winds this morning at 5-10 kts, continuing for the inland terminals. Winds shift SSW for PVD and Cape/Island terminals mid-afternoon. Local seabreezes develop this afternoon along the east coast (BOS). Timing is moderate confidence, but should more likely develop between 17-20Z. Winds shift back toward S/SSW 00-03Z.

Tonight...High Confidence.

VFR. Light SW winds less than 10 kts.

Wednesday...High Confidence.

VFR. Mid-level ceilings developing through the day. Winds SSW 5-10 kts for most terminals. S/SSE winds for BOS around 8-12 kts.

KBOS Terminal...Moderate confidence (sea breeze timing). Sea breeze develops more likely between 17-20Z. Earliest 16Z and latest 21Z. Low probability that sea breeze remains just offshore. KBDL Terminal...High confidence in TAF.

Outlook /Wednesday Night through Saturday/...

Wednesday Night: VFR.

Thursday: Mainly VFR, with local IFR possible. Windy with local gusts up to 30 kt. Chance SHRA, slight chance TSRA.

Thursday Night: VFR. Breezy. Slight chance SHRA.

Juneteenth through Saturday: VFR. Breezy.

MARINE

Forecaster Confidence Levels...

Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent.

Through Wednesday: High confidence.

Winds and seas to remain below Small Craft Advisory thresholds through Wednesday. Could see some gusts around 20 kt this afternoon around the Cape and islands, especially across the southern coastal waters.

Outlook /Wednesday Night through Saturday/...

Wednesday Night: Winds less than 25 kt. Areas of seas approaching 5 ft.

Thursday: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Areas of rough seas. Chance of rain showers.

Thursday Night: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Rough seas up to 9 ft. Chance of rain showers.

Juneteenth through Friday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Slight chance of rain showers.

Saturday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft.

BOX WATCHES/WARNINGS/ADVISORIES

CT...None. MA...None. RI...None. MARINE...None.