Lexington, Massachusetts, USA
Point Forecast Updated Sat Apr 20, 2024 9:22am EDT
Clouds briefly decrease tonight, but increase again on Sunday as a fast-moving frontal system moves through. This should bring another round of light rain showers, but there is a chance for isolated thunderstorms across portions of CT, RI and south of the Mass Pike in MA Sunday afternoon and night. Showers diminish Sunday night, setting the stage for a mild and dry start to the work week. More unsettled by mid week, with a large degree of uncertainty revolving around temperatures and precipitation timing.
Rain Showers
Hi 61 °F
Rain showers and patchy fog. Cloudy, with a high near 61. Southwest wind 6 to 9 mph. Chance of precipitation is 100%. New rainfall amounts between a tenth and quarter of an inch possible.
Chance Rain Showers then Patchy Frost
Lo 36 °F
A chance of rain showers before 8pm, then patchy frost. Partly cloudy, with a low around 36. West wind 5 to 10 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.
Patchy Frost then Mostly Sunny
Hi 59 °F
Patchy frost before 7am. Mostly sunny, with a high near 59. West wind 6 to 14 mph, with gusts as high as 25 mph.
Mostly Clear
Lo 39 °F
Mostly clear, with a low around 39. West wind 8 to 12 mph, with gusts as high as 22 mph.
Sunny
Hi 57 °F
Sunny, with a high near 57. Northwest wind 12 to 15 mph.
Clear
Lo 34 °F
Clear, with a low around 34. West wind 3 to 12 mph.
Mostly Sunny
Hi 62 °F
Mostly sunny, with a high near 62. Southwest wind 5 to 14 mph, with gusts as high as 24 mph.
Mostly Cloudy then Slight Chance Rain Showers
Lo 44 °F
A slight chance of rain showers after 5am. Mostly cloudy, with a low around 44. South wind 13 to 16 mph, with gusts as high as 28 mph.
Rain Showers Likely
Hi 59 °F
Rain showers likely. Mostly cloudy, with a high near 59. South wind 14 to 17 mph. Chance of precipitation is 60%.
Rain Showers Likely
Lo 36 °F
Rain showers likely before 5am. Mostly cloudy, with a low around 36. West wind around 17 mph. Chance of precipitation is 60%.
Mostly Sunny
Hi 52 °F
Mostly sunny, with a high near 52. Northwest wind around 17 mph.
Partly Cloudy
Lo 36 °F
Partly cloudy, with a low around 36. West wind 12 to 16 mph.
Mostly Sunny
Hi 58 °F
Mostly sunny, with a high near 58. Northwest wind around 13 mph.
Partly Cloudy
Lo 39 °F
Partly cloudy, with a low around 39. Northwest wind 8 to 13 mph.
Updated Sat Apr 20, 2024 9:22am EDT
000 FXUS61 KBOX 140213 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 1013 PM EDT Sat Apr 13 2024 .SYNOPSIS... Clouds briefly decrease tonight, but increase again on Sunday as a fast-moving frontal system moves through. This should bring another round of light rain showers, but there is a chance for isolated thunderstorms across portions of CT, RI and south of the Mass Pike in MA Sunday afternoon and night. Showers diminish Sunday night, setting the stage for a mild and dry start to the work week. More unsettled by mid week, with a large degree of uncertainty revolving around temperatures and precipitation timing. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... 1005 PM Update: Earlier scattered showers have continued to dissipate, but still dealing with a good deal of cloud cover and westerly winds around 10-15 mph (around 20 mph Cape and Islands) with gusts 20-30 mph. Brought hourly temps up by 3-5 degrees over inherited forecast thru early overnight to account for slow cooling under clouds and the breezes with this update, but cloud cover should begin to decrease more significantly after midnight coinciding with eastward passage of 500 mb trough axis into the Canadian Maritimes. That also should bring easing gust speeds too, although sustained winds still will run around 10 mph for most of the night. Forecast for second half of the night seems to reflect these expectations well and made no changes there with this update. Previous Discussion... A smattering of diurnal showers continues across much of southern New England this afternoon driven largely by the broad trough passing overhead. The axis of said trough (now just east of the region) will continue to march east through the evening as the shortwave lifts out. This loss of synoptic forcing together with loss of daytime heating will mean diminishing showers and cloud coverage toward sunset, with skies really clearing after 2-3AM. As mid level heights briefly rise we'll end the night and start Sunday with mostly clear skies. While winds will remain breezy overnight, temps should drop several degrees compared to lows last night under the cooler air mass, into the upper 30s/low 40s. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... If you get outside during the morning hours tomorrow you should be able to get enjoy party sunny skies, though an approaching warm front and associated mid level trough will mean skies quickly cloud over after noon. It will be followed quickly by a cold front as the weak surface low passes overhead or just to our north Sunday afternoon and evening. Given the 30-60 kt LLJ passing just offshore and a modest PWAT plume of ~1 inch this frontal system should bring anywhere from a few hundredths of an inch to a half inch of rain. Hi- resolution guidance is in general agreement that we'll see two distinct rounds of rain: first some light warm advection showers in the late morning/early afternoon followed by a lull and then a round of heavier rain accompanying the cold front Sunday evening. Where confidence is lower is how much drying we'll have between these rounds or if showers hang around much of the day. There remains potential for some rumbles of thunder ahead of the cold front as well, depending on how far the warm sector extends east into southern New England. Currently decent mid-level lapse rates (6.5- 7.5C/km) and a few hundred J/kg of CAPE extend into western CT/MA where the best chance of thunder will be in the afternoon, and the SPC has these locations under a Marginal Risk (level 1 of 5) of severe storms. Can't rule out a rumble of thunder along the immediate south coast later in the evening as the low passes. The cold front and line of rain/thunderstorms should move off of Cape Cod by midnight leaving rapidly clearing skies under drying NW flow. && .LONG TERM /MONDAY THROUGH SATURDAY/... Highlights: * Drying trend develops Monday and Tuesday * Mild start to the week, uncertainty in temperatures the second half of the work week * Unsettled conditions should return late Wednesday into next weekend Much of this portion of the forecast should feature a broad mid level over southern New England through early next week. A stronger mid level cutoff should move from Hudson Bay to the Saint Lawrence Valley during this time as well. We should catch a brief break beneath a ridge towards Wednesday. After then though, there is quite a bit of uncertainty in the synoptic details within the latest guidance suite. Have sketched out a general period of unsettled weather from late Wednesday into next Saturday, but fully expecting the timing details to change with later forecasts. Not much different at the surface. High pressure starts to build across southern New England for Monday, but is more in place for Tuesday. Thus, despite the trough aloft, thinking we will see dry weather with at least some sunshine. Will have to monitor the humidity, as this could be a setup for more diurnal clouds, at least for Monday. Then the aforementioned timing issues become more of a factor. High pressure should move off to the east, opening a path for a low pressure to impact our region sometime from late Wednesday into Thursday morning. This low pressure is currently projected to move offshore for Friday, but a warm front should be lingering nearby. A cold front should sweep most of the unsettled weather out over the North Atlantic for Saturday, assuming the current timing holds. Temperatures expected to be near to above normal through this portion of the forecast. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High- greater than 60 percent. Tonight: High confidence. VFR. Clearing skies by 06Z. West winds around 10-13 kt with diminishing gusts. Sunday: High confidence in trends, moderate in exact timing. Quick-moving frontal system from the Great Lakes spreads increasing/lowering cloud bases into the VFR/MVFR range. Best chance of scattered showers during the afternoon after 18z; there could be a rumble or two of thunder south and west of a BDL-PVD line later in the day but confidence is on the low side. W winds shift to SW then S around 10-12 kt. Sunday night: High confidence. VFR for most terminals except IFR in the high terrain of central MA (ORH) early, but cigs will be lifting region-wide. Showers move off of Cape Cod by 04Z. SW winds becoming lighter and turning to the NW after 06Z. KBOS TAF...High confidence in TAF. KBDL TAF...High confidence in TAF. Outlook /Monday through Thursday/... Monday: VFR. Breezy. Monday Night: VFR. Tuesday: VFR. Breezy. Tuesday Night: VFR. Wednesday: VFR. Chance SHRA. Wednesday Night: MVFR/IFR conditions possible. Breezy. SHRA likely. Thursday: MVFR/IFR conditions possible. Breezy. Chance SHRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. High confidence... Gusty SW to W wind gusts 25-30 kt on the eastern waters, and up to 35 kt on the southern nearshore and offshore waters. Winds subside later tonight. Seas will remain elevated and rough, around 7-10 ft on the outer waters. Sunday morning SW gusts ramp up again to around 15-20 kt with seas around 4-6 ft on Sunday. Winds gust to 20-30 kts during the early overnight hours, diminishing after midnight. Chance for a few t-storms on the far southern outer waters very late Sunday afternoon, but at least scattered showers develop during the afternoon on all waters. Outlook /Monday through Thursday/... Monday: Winds less than 25 kt. Local rough seas. Monday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Tuesday through Tuesday Night: Winds less than 25 kt. Wednesday: Winds less than 25 kt. Chance of rain showers. Wednesday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas locally approaching 5 ft. Chance of rain showers. Thursday: Moderate risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 2 AM EDT Sunday for ANZ230-236. Small Craft Advisory until 8 AM EDT Sunday for ANZ231-251. Gale Warning until 2 AM EDT Sunday for ANZ232-254>256. Small Craft Advisory until 8 PM EDT Sunday for ANZ233>235-237- 250. && $$ SYNOPSIS...Belk/BW NEAR TERM...Belk/Loconto/BW SHORT TERM...BW LONG TERM...Belk AVIATION...Belk/Loconto/BW MARINE...Belk/Loconto/BW
Point forecast:
https://api.weather.gov/gridpoints/BOX/65,93/forecast
Zone forecast:
https://api.weather.gov/zones/forecast/MAZ014/forecast
Hourly forecast:
https://api.weather.gov/gridpoints/BOX/65,93/forecast/hourly
Hourly detail:
https://api.weather.gov/gridpoints/BOX/65,93
Point detail:
https://api.weather.gov/points/42.4399,-71.2405
Alerts:
https://api.weather.gov/alerts?active=1&point=42.4399,-71.2405