textproduct: Boston / Norton

WHAT HAS CHANGED

No significant changes to the forecast.

KEY MESSAGES

- Dry and increasingly warm through the remainder of the week.

- Unsettled and cooler conditions this weekend into early next week.

DISCUSSION

KEY MESSAGE 1...Dry and increasingly warm through the remainder of the week.

Continued confidence in a stretch of dry weather through the workweek as a broad upper level ridge of high pressure builds over the central and eastern CONUS. Kept the short term forecast largely the same as high pressure appears to be working in on schedule.

Story of the week will be increasing temperatures as 850 mb temperatures incrementally warm to between +13C and +15C by Thursday and Friday. While these temperatures alone would support highs in the lower to middle 80s, west-northwest flow aloft descending from the higher terrain of western Massachusetts should promote compressional warming/downsloping. Probabilities for >90 degree high temperatures Thursday and Friday have decreased somewhat as guidance is honing in on more mid and high-level cloud cover. Still, the latest Heat Risk guidance shows level 2/5 values across the interior Thursday and Friday. These values suggest temperatures that may become warm enough to affect those who are sensitive to heat, such as those without adequate access to cooling and hydration.

KEY MESSAGE 2...Unsettled and cooler conditions this weekend into early next week.

One day later, and the details of the forecast this weekend into early next week are not much clearer. Still noting timing variabilities within the guidance suite.

Looking toward the weekend, forecast confidence lowers due to variability among guidance. The broad thinking remains that surface high pressure shifts offshore, mid-level heights fall, and cooler temperatures advect aloft. The GFS is most aggressive with its mid level trough heading into this weekend when compared to its international counterparts. Will continue to favor a probabilistic/ensemble approach for this portion of the forecast.

ALl that said, still thinking that much of southern New England could remain dry Saturday. Northern and western MA would be most at risk for a later afternoon shower. Increasing risk for showers Saturday night and especially Sunday as a low pressure makes its closest approach. Favoring drier weather for Monday and Tuesday. A more noticeable cooldown, although still near normal for early June, is anticipated for Sunday into Tuesday.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/

Forecaster Confidence Levels...

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

Through Wednesday Night...High confidence.

VFR. Dry conditions through Wednesday. Overnight, light to calm winds prevail, followed by light northwest winds across interior locations as high pressure settles into the region on Wednesday. Sea breeze redevelops Wednesday morning between 14 and 16z.

KBOS...High confidence in TAF.

VFR through the TAF period. Sea breeze continues through 02z followed by light winds overnight and then a weak sea breeze between 14 and 16z Wednesday.

KBDL...High confidence in TAF.

VFR. Light to calm winds overnight becoming light northwest Wednesday.

Outlook /Thursday through Sunday/...

Thursday: VFR. Breezy.

Thursday Night: VFR.

Friday: VFR. Breezy.

Friday Night: VFR.

Saturday: VFR. Breezy. Slight chance SHRA.

Saturday Night: VFR. Chance SHRA, slight chance TSRA.

Sunday: Mainly VFR, with local IFR possible. Breezy. Chance SHRA.

MARINE

Forecaster Confidence Levels...

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

Through Wednesday...High confidence.

In general, conditions today through Wednesday will support tranquil boating conditions as surface high pressure remains the dominant feature. Dry conditions persist into Wednesday. Winds become light and somewhat variable on Wednesday as high pressure settles over the region. However, colder sea surface temperatures relative to warmer land temperatures will promote onshore winds across waters near the immediate coast. Seas of 1 to 3 feet on Wednesday.

Outlook /Thursday through Sunday/...

Thursday: Winds less than 25 kt.

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

Friday: Winds less than 25 kt. Seas locally approaching 5 ft.

Friday Night: Winds less than 25 kt. Seas up to 5 ft.

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

Saturday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers, slight chance of thunderstorms.

Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers.

BOX WATCHES/WARNINGS/ADVISORIES

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