textproduct: Boston / Norton

WHAT HAS CHANGED

Trended forecast drier tonight into Thursday.

KEY MESSAGES

- Cloudy with patchy fog tonight. Becoming sunny by Thursday afternoon. Near normal temperatures expected.

- Generally dry conditions expected through early next week, except a few low end chances for showers Sunday, with below average temperatures.

DISCUSSION

KEY MESSAGE 1...Cloudy with patchy fog tonight. Becoming sunny by Thursday afternoon. Near normal temperatures expected.

A weak low pressure passes by to our southwest tonight. A weak surface trough should also pass by around daybreak Thursday, eventually shifting winds to the west to northwest. This is a low chance for a few stray showers with this trough, but there does not appear to be much moisture to work with. At this time, favoring cloudy and drier conditions tonight into Thursday morning. Kept the mention of light showers out of this forecast update.

The clouds tonight and weak south winds should keep low temperatures closer to normal for late April, which then leads to near normal high temperatures once the sun breaks out during Thursday. Despite light north to northwest winds Thursday night, temperatures should stay near average.

Boundary layer mixing and lowering dew points will lead to possible fire weather concerns Thursday. Expecting gusty west to northwest winds of 15-25 mph and minimum relative humidity values of 25-35 percent. These conditions probably overlap for only a few hours before sundown.

KEY MESSAGE 2...Generally dry conditions expected through early next week, except a few low end chances for showers Sunday, with below average temperatures.

A rather stagnant upper-level pattern dominates through most of the weekend, bringing overall dry conditions to southern New England through the weekend. Ensemble guidance shows 850mb temperatures hovering near or just below 0C through Sunday, allowing for surface temperatures to remain below normal... generally in the mid to upper 50s. Guidance also continues to hone in on chances for brief rain showers Saturday night, but confidence remains low at this time as the airmass is projected to remain rather dry.

Expecting high temperatures to continue to climb into the high 50s or low 60s for the start of the next work week, with dry weather continuing.

AVIATION /00Z THURSDAY THROUGH MONDAY/

Forecaster Confidence Levels...

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

Tonight: Moderate confidence.

Ceilings deteriorate to MVFR/IFR, which should continue into the pre-dawn Thursday hours. Likely BR, but uncertain if we'll get low enough VISBY for FG. Winds go light southeast.

Thursday: High confidence.

Sub-VFR ceilings continue early but should begin to lift/scatter to VFR bases with winds becoming WSW 5-10 kt. Winds then shift NW and increase to 10-13 kt with gusts 22-25 kt late in the day.

Thursday Night...High confidence.

VFR. Ligth northwesterly winds 7-12 kts.

KBOS Terminal...Moderate confidence in TAF. Expecting CIGS to continue to drop to low-end MVFR through midnight. Low risk for IFR, but not usually the case with S winds becoming light SE overnight. VFR for Thursday.

KBDL Terminal...Moderate confidence in TAF. MVFR eventually lowers to IFR overnight. VFR by the Thursday morning push.

Outlook /Friday through Monday/...

Friday through Friday Night: VFR.

Saturday: VFR. Slight chance SHRA.

Saturday Night: Mainly VFR, with local IFR possible. Slight chance SHRA.

Sunday through Sunday Night: VFR. Slight chance SHRA.

Monday: VFR.

MARINE

Forecaster Confidence Levels...

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

High confidence through this weekend.

Relatively light winds and seas expected through Thursday night. Could be a few nearshore gusts up to 20 kt, but seas expected to remain less than 5 feet.

Outlook /Friday through Monday/...

Friday through Saturday: Winds less than 25 kt.

Saturday Night through Monday: Winds less than 25 kt. Slight chance of rain showers.

BOX WATCHES/WARNINGS/ADVISORIES

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