Weston, Massachusetts, USA
52.9°F
11.6°C
Cool
Mostly Cloudy
Tonight: Lo 46 °F
Friday: Hi 56 °F
Dew Point: 47.3°F
Humidity: 81%
Barometer:
mb
Rain Rate: 0.00 in/hr
Rain Today: 0.00 in
Rain Wednesday: 0.81 in
Visibility: 10 miles
Wind:
Now: Calm
Avg: 0 mph
Gusts: 3 mph
Issued by:
National Weather Service Boston / Norton, MA
Point Forecast Updated Thu May 9, 2024 6:10pm EDT
High pressure to the north brings mainly dry and mild conditions this afternoon. Some showers are possible this evening into early Friday as low pressure tracks to the south, otherwise drier and cooler for much of Friday as NE winds develop. Cooler than normal this weekend with rain chances increasing Saturday night and Sunday, then milder temperatures return early next week but an unsettled pattern persists.
Mostly Cloudy then Chance Rain Showers
Lo 46 °F
A chance of rain showers after 1am. Mostly cloudy, with a low around 46. East wind 5 to 8 mph. Chance of precipitation is 30%.
Chance Rain Showers then Mostly Cloudy
Hi 56 °F
A chance of rain showers before 11am. Mostly cloudy, with a high near 56. Northeast wind 6 to 12 mph. Chance of precipitation is 30%.
Mostly Cloudy
Lo 42 °F
Mostly cloudy, with a low around 42. Northeast wind 5 to 10 mph.
Partly Sunny
Hi 56 °F
Partly sunny, with a high near 56. Northeast wind 6 to 10 mph.
Slight Chance Rain Showers
Lo 42 °F
A slight chance of rain showers after 10pm. Mostly cloudy, with a low around 42. Northeast wind 3 to 8 mph. Chance of precipitation is 20%.
Chance Rain Showers
Hi 58 °F
A chance of rain showers before 2pm, then a chance of showers and thunderstorms. Mostly cloudy, with a high near 58. Northeast wind around 6 mph. Chance of precipitation is 30%.
Partly Cloudy
Lo 44 °F
Partly cloudy, with a low around 44. South wind around 8 mph.
Mostly Sunny then Slight Chance Rain Showers
Hi 68 °F
A slight chance of rain showers after 5pm. Mostly sunny, with a high near 68. Southwest wind 7 to 14 mph.
Chance Rain Showers
Lo 52 °F
A chance of rain showers. Mostly cloudy, with a low around 52. Southwest wind around 14 mph. Chance of precipitation is 30%.
Chance Showers And T-Storms
Hi 75 °F
A chance of rain showers before 11am, then a chance of showers and thunderstorms. Partly sunny, with a high near 75. Southwest wind 12 to 17 mph. Chance of precipitation is 30%.
Chance Showers And T-Storms
Lo 56 °F
A chance of showers and thunderstorms. Mostly cloudy, with a low around 56. South wind 12 to 17 mph. Chance of precipitation is 40%.
Chance Rain Showers
Hi 66 °F
A chance of rain showers. Mostly cloudy, with a high near 66. Southeast wind around 12 mph. Chance of precipitation is 40%.
Chance Rain Showers
Lo 53 °F
A chance of rain showers. Mostly cloudy, with a low around 53. Northeast wind around 12 mph. Chance of precipitation is 40%.
Chance Rain Showers
Hi 69 °F
A chance of rain showers. Partly sunny, with a high near 69. Northeast wind around 13 mph. Chance of precipitation is 50%.
Issued by:
National Weather Service Boston / Norton, MA
Updated Thu May 9, 2024 6:10pm EDT
000 FXUS61 KBOX 092011 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 411 PM EDT Thu May 9 2024 .SYNOPSIS... High pressure to the north brings mainly dry and mild conditions this afternoon. Some showers are possible this evening into early Friday as low pressure tracks to the south, otherwise drier and cooler for much of Friday as NE winds develop. Cooler than normal this weekend with rain chances increasing Saturday night and Sunday, then milder temperatures return early next week but an unsettled pattern persists. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... IR satellite imagery shows a band of moisture moving in which has moved over the southern half of SNE this afternoon increasing cloudcover and allowing some very light returns to bloom on the radar mainly off shore. Overall the dry day will continue for most of the region thanks to some subtle mid level ridging and a drier airmass further north, but we will see some scattered showers moving into northeast MA this evening on cool NE flow. Not everyone in northeast MA will see a shower, and they will be transient in nature. The more widespread showers tonight will occur over the southern and western parts of the region as a subtle shortwave passes overhead providing enough synoptic lift acting on the ~1" PWAT plume to produce rain showers overnight, generally light (a few tenths to a few hundredths). && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... Tonight... As mid level trough amplifies over the Gt Lakes, backing flow aloft will bring increasing moisture northward into SNE. However, there is uncertainty regarding how far north and east showers will get across SNE as best moisture will remain to the SW. Best chance for a period of rain tonight will be from western MA to RI closest to best moisture, with decreasing probs further NE into portions of eastern and NE MA. Lows will be in the 40s tonight, with increasing NE winds along the south coast and Cape/Islands as low pres moves off the mid Atlc coast. Friday... Some lingering showers are possible Fri, especially across SW portions of SNE, but drier air will gradually move in from the north during the day as high pres builds south into eastern New Eng. This may lead to partial sunshine developing across portions of northern and eastern MA. NE flow will result in cooler temps Fri with highs mostly in the 50s, with some lower 60s possible in the CT valley. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Highlights * Dry for much of Sat, but there could be some spotty showers across the interior late. * Hit or miss showers and perhaps a few rumbles of thunder on Sun. Could have some graupel/small hail with any stronger storms. * Dry for much of Mon with a return of seasonable temps. * Unsettled late Mon into midweek as a frontal boundary slides through. Though there is considerable uncertainty in how exactly things will evolve. Saturday... Stuck under cyclonic flow through this timeframe with a trough over the central Great Lakes early on Sat and a shortwave ridge over the eastern Great Lakes/Mid Atlantic. The shortwave ridge builds into southern New England by the afternoon, while the trough digs into the eastern Great Lakes/Mid Atlantic. The ridge axis slides offshore Sat eve. A weak high nudges into our region through much of this timeframe. A broad low slides into the eastern Great Lakes late in the day. Overall anticipating that the weather will be dry and quiet for much of the day albeit still unseasonably cool due to onshore flow. The onshore flow coupled with height falls later on Sat and diurnal heating could bring some spotty showers during the afternoon. Not super confident on this as forcing is quite weak and AOA measurable 24 hr QPF probs continue to diminish per EPS/GEFS and GEPS guidance from run to run. Should have fairly cool air in place with onshore flow. At this point 925 hPa temps range from roughly 1-8 degrees Celsius with the mildest temps across the Berkshires. The NBM temps actually seemed pretty dialed in at this point, so haven't made any changes. Highs range from the low 50s along the east coast to the low 60s across the CT River Valley. Sunday... The trough over the eastern Great Lakes late on Sat will lift into and perhaps through portions of New England during this period. There is potential that we get a cutoff beginning to set up over the region. A broad low will be in place nearby or over southern New England during this timeframe. Think this is our next opportunity for hit/miss showers and perhaps a few thunderstorms. We really do not have a whole lot of moisture to work with as EPS/NAEFS situational awareness tables indicating that PWATs are around -0.5 to -1 STD below model climo. This translates to PWATs roughly around 0.5". Though we do have anomalously low 500 hPa height overhead (-2 STD per both SATA tables). The 500 hPa trough/cutoff overhead is also quite cold with temps of -20 to -25 degrees Celsius. This in combination with diurnal heating should result in hit/miss shower and thunderstorm activity. Given the cold core in place do think there could be some graupel/small hail if any more vigorous showers/storms can develop. Should note that mid level lapse rates are around 5-7 degrees Celsius with low level lapse rates around 5-8 degrees Celsius. Though these lapse rates really depend on the deterministic model being viewed, so there is considerable uncertainty given the weak forcing. Deep layer shear in the 0-6 km layer is quite low at this point, so not anticipating any strong/severe storms. Though given the environment think there could be some small hail pending how much instability is in place. The longer term convective allowing guidance, ie the NCAR MPAS and C- SHiELD do show max vertically integrated graupel spottiness over the Northeast of 0.1 to roughly 0.5 inches. Though again appears very hit/miss in nature. Could have a bit of MUCAPE in place, but guidance all over the place. Most robust is with the NCAR MPAS with a few hundred J/kg over western MA/CT. Stay tuned for future updates. Monday through Wednesday... Still caught under cyclonic flow through this timeframe with a cutoff in place over Quebec/Ontario/Hudson Bay. A ridge axis flattens out as it is building into the Mid Atlantic on Mon. A shortwave begins lifting in on Tue and behind it a deeper trough may slide in for Wed. A weak high nudges in for a good portion of Monday before a frontal boundary slides in late in the day. The front may still be sliding in on Tue or overhead and into Wed. Dry and quiet weather anticipated for much of Mon with high pressure nudging into our region from offshore of the Mid Atlantic. Late in the day some guidance begins sliding a front in, but lots of discrepancy here. So, have just stuck with the NBM at this point in time. We should rebound temp wise quite nicely to more seasonable values, ie readings in the 60s to low 70s. The front will still be overhead and perhaps working its way through on Tue/Wed. Though there is a lot of uncertainty in how things evolve as a deeper low could ride along the front bringing us heavier rains or kicking the front offshore. Ensemble guidance is also spread with the EPS a bit more amped up (like the ECWMF) with moderate/high probs (30-80 percent) of 24 hr QPF AOA 0.5 inches into Wed. The GEPS/GEFS show low probs (10-30 percent) of the same QPF binning. The EPS even showing some low probs of 24 hr QPF AOA 1 inch. Something to keep an eye on as we get closer, but for now think that the NBM suffices. Temperatures trending near to above normal through this period. && .AVIATION /20Z THURSDAY THROUGH TUESDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 18Z TAF Update: This afternoon...Moderate confidence. VFR. N wind around 10 kt turning NE during the afternoon. Tonight...Moderate confidence. MVFR cigs expanding westward across western and central SNE terminals. Low prob for IFR. MVFR expected to stay out of eastern MA terminals but confidence is only moderate. Scattered showers developing, especially across western half New Eng. NE wind 5-15 kt. Friday...Moderate confidence. Cigs improving to VFR from NE to SW as drier air works in from the N. A few showers possible, mainly from SW MA and CT to the south coast. Friday night...moderate confidence. NE winds diminishing overnight. VFR except for marginal MVFR cigs over the Cape and islands. KBOS TAF...Moderate confidence in timing of wind shift to NE. KBDL TAF...High confidence in TAF today. Outlook /Saturday through Tuesday/... Saturday: VFR. Breezy. Slight chance SHRA. Saturday Night: Mainly VFR, with local MVFR possible. Slight chance SHRA. Sunday: Mainly VFR, with local MVFR possible. Slight chance SHRA, isolated TSRA. Sunday Night: VFR. Monday through Monday Night: VFR. Breezy. Slight chance SHRA. Tuesday: VFR. Breezy. Chance SHRA, isolated TSRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Through Friday night... Northeast winds below 20 kt may increase with gusts 20-25 kt tonight into Fri, especially over south coastal waters as low pres tracks to the south. Seas build to near 5 ft over the eastern outer waters late tonight into Friday night. A SCA may be needed for eastern MA waters toward Saturday but conditions are marginal. Outlook /Saturday through Tuesday/... Saturday through Sunday: Winds less than 25 kt. Seas up to 5 ft. Slight chance of rain showers. Sunday Night through Monday: Winds less than 25 kt. Areas of seas approaching 5 ft. Monday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Slight chance of rain showers. Tuesday: Moderate risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Slight chance of rain showers, isolated thunderstorms. && .TIDES/COASTAL FLOODING... High astronomical tides coupled with onshore flow may result in some splashover/very minor coastal flooding during the overnight high tide cycle tonight. However, wind/waves do not appear high enough to result in a significant issue. The daytime high tides are lower and do not pose a threat for coastal flooding. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...None. && $$ SYNOPSIS...BW/BL NEAR TERM...BW SHORT TERM...BW LONG TERM...BL AVIATION...BW/BL MARINE...BW/BL TIDES/COASTAL FLOODING...
Radar images courtesy Weather Underground / Intellicast.
UV Index forecast high for today: 6 High
Current (Estimated): 0 None
Note: Rain measured automatically by weather station. Rain totals do not necessarily include melted frozen precipitation.
For more accurate, manually measured rain data, see the Local Precip Data page.
0.00 in
Rain Rate (/hr):
0.00 in
Rain Last 60 min:
0.00 in
Rain Today:
0.81 in
Wednesday:
1.52 in
May:
25.45 in
2024
1:42pm
66.4°F
High today:
7:26am
51.1°F
Low today:
3:51pm
58.8°F
High Wednesday:
5:40am
48.6°F
Low Wednesday:
5:40am
48.6°F
Low wind chill Wednesday:
1:58am
54.5°F
High dew pt today:
3:51pm
57.9°F
High dew pt Wednesday:
12:30pm
16 mph
Wind gust today:
4:41pm
10 mph
Wind gust Wednesday:
No alerts/warnings active for Central Middlesex County.
Alerts active nearby in: Coastal Rockingham, NH; Coastal Waters extending out to 25 nm South of Marthas Vineyard and Nantucket; Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 nm South of Block Island; Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 nm
First Light:
4:58am
Sunrise:
5:29am
Sunset:
7:54pm
Twilight ends:
8:26pm
Daylight length:
14 hours 25 minutes
Phase:
Waxing Crescent (4%)
Moon rise:
6:07am
Moon set:
10:19pm