Lexington, Massachusetts, USA
69.4°F
20.8°C
Muggy
Clear
Tonight: Lo 68 °F
Sunday: Hi 97 °F
Dew Point:
66.7°F
Humidity:
91%
Barometer:
mb
Rain Rate: 0.00 in/hr
Rain Today: 0.00 in
Rain Saturday: 0.02 in
Visibility: 10 miles
Wind:
Now: Calm
Avg: Calm
Gusts: 1 mph
Alerts active nearby in: Central Middlesex County, MA; Cheshire, NH; Eastern Franklin, MA; Eastern Hampden, MA; Eastern Hampshire, MA; Eastern Hillsborough, NH; Eastern Kent, RI; Eastern Norfolk, MA; Hartford, CT; Interior Rockingham, NH; Northern Bristol, MA; Northern Worcester, MA; Northwest Middlesex County, MA; Northwest Providence, RI; Southeast Middlesex County, MA; Southeast Providence, RI; Southern Worcester, MA; Suffolk, MA; Tolland, CT; Western And Central Hillsborough, NH; Western Essex, MA; Western Kent, RI; Western Norfolk, MA; Western Plymouth, MA; Windham, CT
Issued by:
National Weather Service Boston / Norton, MA
Point Forecast Updated Sat May 21, 2022 6:53pm EDT
Near record high temps with Heat Indices between 95 and 100 degrees are expected Sunday away from the south coast. A few strong to severe thunderstorms are possible from mid-afternoon into the early hours on Sunday across interior southern New England. A return to cooler/seasonable temps follows Monday into mid-week with dry weather. Warmer temps and humidity return by the end of the week along with the risk for a round of showers and thunderstorms with a cold front on Friday.
Mostly Clear then Patchy Fog
Lo 68 °F
Patchy fog after 4am. Mostly clear, with a low around 68. Southwest wind around 3 mph.
Sunny then Chance Showers And T-Storms
Hi 97 °F
A chance of showers and thunderstorms after 3pm. Sunny, with a high near 97. Southwest wind 2 to 17 mph. Chance of precipitation is 30%.
Showers And T-Storms Likely then Mostly Cloudy
Lo 61 °F
Showers and thunderstorms likely before 11pm. Mostly cloudy, with a low around 61. West wind 9 to 15 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.
Mostly Sunny
Hi 74 °F
Mostly sunny, with a high near 74. North wind 7 to 12 mph.
Mostly Cloudy
Lo 54 °F
Mostly cloudy, with a low around 54. North wind around 7 mph.
Mostly Sunny
Hi 66 °F
Mostly sunny, with a high near 66. Northeast wind 7 to 10 mph.
Mostly Cloudy
Lo 47 °F
Mostly cloudy, with a low around 47. Southeast wind 2 to 9 mph.
Partly Sunny then Slight Chance Rain Showers
Hi 70 °F
A slight chance of rain showers after 4pm. Partly sunny, with a high near 70. Southeast wind 3 to 10 mph.
Chance Rain Showers
Lo 54 °F
A chance of rain showers. Mostly cloudy, with a low around 54. South wind 5 to 9 mph. Chance of precipitation is 40%.
Chance Rain Showers
Hi 70 °F
A chance of rain showers. Mostly cloudy, with a high near 70. South wind 5 to 9 mph. Chance of precipitation is 40%.
Chance Rain Showers
Lo 59 °F
A chance of rain showers. Mostly cloudy, with a low around 59. South wind around 8 mph. Chance of precipitation is 50%.
Chance Rain Showers
Hi 77 °F
A chance of rain showers. Mostly cloudy, with a high near 77. South wind 7 to 14 mph. Chance of precipitation is 50%.
Chance Rain Showers
Lo 60 °F
A chance of rain showers. Mostly cloudy, with a low around 60. Southwest wind 7 to 13 mph. Chance of precipitation is 50%.
Chance Rain Showers
Hi 76 °F
A chance of rain showers. Mostly sunny, with a high near 76. West wind 8 to 12 mph. Chance of precipitation is 40%.
Issued by:
National Weather Service Boston / Norton, MA
Updated Sat May 21, 2022 6:53pm EDT
000 FXUS61 KBOX 220147 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 947 PM EDT Sat May 21 2022 .SYNOPSIS... Near record high temps with Heat Indices between 95 and 100 degrees are expected Sunday away from the south coast. A few strong to severe thunderstorms are possible from mid-afternoon into the early hours on Sunday across interior southern New England. A return to cooler/seasonable temps follows Monday into mid-week with dry weather. Warmer temps and humidity return by the end of the week along with the risk for a round of showers and thunderstorms with a cold front on Friday. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... 930 PM Update... Fairly quiet evening across the region with temperatures falling back into the 60s and 70s for the most part. Coolest spot remains ACK where the temp is 57F and conversely the warmest is BDL at 80F. Overall the forecast does remain on track tonight and we only had to modify near term temperatures to bring back in line with the observations. Satellite shows clear skies and a bank of low stratus north of Cape Ann. We do still expect low stratus and fog to redevelop along the coast tonight, but not as extensive at last night. Overall forecast remains in good shape. Please see previous discussions for more information. 630 PM Update... Sea-breeze circulation beginning to weaken as winds begin to prevail out of the south/southwest for this evening. Temperature still in the low 60s at BOS, may see a warm up in the city this evening as winds shift to the south/southwest and push that cool maritime air offshore. Elsewhere temperatures remain hot in the upper 80s to low 90s across the interior. We are past peak heating and thus should begin to see temperatures start falling soon. Temperatures will remain mild tonight across the interior with lows struggling to fall below 70 degrees. Closer to the coast expect temps to fall to the low to mid 60s. May see some patchy fog develop near the coastal areas of The Cape Islands tomorrow morning as well. See previous discussion for more details. Previous Discussion Tonight... * Unseasonably mild & a bit muggy tonight Upper level ridging centered to our south will remain in control of our weather tonight. Despite an EML in place along with impressive instability; upper level ridging and a capping inversion will keep us dry tonight. Low risk of a spot shower/t-storm across far northwest MA this evening; but it would be short-lived if it even happened so opted not to include in the forecast. The main story tonight will be unseasonably mild and somewhat muggy conditions. Low temperatures should only drop into the middle to upper 60s except near the south coast, Cape and Islands where onshore flow will result in overnight lows in the upper 50s and lower 60s. Surface winds tonight will be light; but from a south to southwest direction. This will confine any risk of low clouds and fog to mainly the Cape/Islands. Across the rest of the region; mainly clear skies should prevail with perhaps just brief patchy ground fog/haze in the typically prone spots. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... Highlights... * Near Record Highs generally in the 93 to 98 degree range Sun to the northwest of a Providence to Taunton line * A few strong-severe t-storms possible across the interior between 2 & 10 pm Sun with locally damaging wind gusts Details... Sunday... 1) Heat & Humidity A hot day is on tap for Sunday with near record high temperatures generally northwest of a Providence to Taunton line. While 850T are around +19C on Sunday; which is a few degrees cooler than today we expect surface temps to be higher. The reasons for this are that we are not expecting the low clouds that we saw this morning; so temperatures will be off to the races much earlier. In addition, mixing will be much better than today and we expect southwest wind gusts of 20-25 mph with perhaps a few gusts near 30 mph. So we are thinking that high temperatures will generally be in the 93 to 98 degree range northwest of a Providence to Taunton area. This includes Boston; which unlike today will have a westerly component to the wind and their temperature will respond. Dewpoints will be a few degrees lower than today; given better mixing. However, Heat Indices on the order of 95 to 100 degree are expected. While these readings are just a few degrees higher than the forecast high temperatures; The Heat Advisory remains valid and will continue away from the south coast. Temps will be cooler near the south coast, Cape and Islands generally in the 70s to the lower 80s given the modified marine airmass with the gusty southwest winds. 2) Strong to Severe Thunderstorm Risk across the Interior The other main concern will be for the development of a few strong to severe thunderstorms during the mid-late afternoon and evening hours across interior southern New England. A strong cold front and pre-frontal trough will be approaching from the west. 0 to 6 KM shear is rather marginal; generally on the order of 20 to 30 knots. In addition...the core of the EML currently in place will be shifting to our east. However, given the anomalous hot airmass in place SPC SREF is indicating high probs of MLCapes exceeding 2000 J/KG along with some low level convergence with the pre-frontal trough. Many high resolution CAMS seem to initiate a few showers and t-storms across the interior after 1 or 2 pm. Perhaps more in the way of activity by late afternoon/early evening as better convergence arrives with the approaching surface cold front. Given the anomalous heat; large temp/dewpoint spreads around 30 degrees are anticipated. This will increase the potential for locally strong to damaging wind gusts roughly between 2 and 10 pm across interior southern New England. We can not rule out a bit of small hail, but thinking locally strong-damaging wind is the main threat. This is supported by the NCAR ensembles as well as the CIPS analogs. Brief heavy rain/typical poor drainage street flooding is also a concern given Pwats on the order of 1.5 to 2 inches. The activity will move east; but should weaken on approach to the I-95 corridor Sunday evening given the later arrival time and increasing marine influence. So we feel the main severe weather threat will be across interior MA & CT. Sunday night... Scattered showers & t-storms weaken Sunday evening as the approach the I-95 corridor. Perhaps a few showers with a rumble of thunder survive, but not expecting much more than that. Otherwise...the rest of Sunday night will feature dry but significantly cooler weather returning. Low temps by daybreak Monday should be back down into the middle 50s to the lower 60s. && .LONG TERM /MONDAY THROUGH SATURDAY/... * Highlights * - Seasonable temperatures early in the week - Increasing temperatures and humidity mid-late week - Thunderstorms possible late week with a passing cold front Monday through Wednesday Anticyclonic flow around a large area of high pressure positioned north and west of New England will result in a northerly flow for the first half of the week. Predominantly northwesterly flow on Monday will support a seasonable day with high temps in the low 70s. By Tuesday the high pressure center is forecast to be due north of southern New England which will result in a more northeasterly flow into the region. This will allow cooler maritime air to advect into the region supporting below normal temperatures for Tuesday and Wednesday, especially along the coast where temperatures will be confined to the low 60s. Wednesday night through Saturday High pressure shifts east of the region late Wednesday/early Thursday bringing us back to a southerly flow pattern. Southerly flow will help lift a warm front through the region Wednesday night into Thursday with some showers and possibly a thunderstorm. Southerly flow persists into Thursday and Friday allowing for an increase in both temperatures and humidity. Temperatures may get back into the 80s Friday afternoon. Models in agreement that a cold- front will push through the region at the end of the week. With a warm/humid air mass in place, the potential will exist for this front to produce thunderstorms in southern New England. A lot of uncertainty at this time range, but will be monitoring the end of next week closely. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. 00Z TAF Update... Through 06Z VFR. Possible IFR/LIFR visibilities at Cape/Islands terminals where fog may redevelop prior to 06Z. Sea-breeze at Boston should fade and transition to a south/southwesterly flow in the next 2 to 3 hours. Some uncertainty in that department, but expect a southerly flow by 03Z. Tonight...High Confidence. VFR conditions should generally prevail outside a bit of patchy ground fog possible overnight in the typically prone spots. The exception might be the Cape & Islands where some IFR-LIFR conditions in low clouds/fog may impact those areas for a portion of the night. Light S winds. Sunday...High Confidence. Mainly VFR conditions expected. However, scattered showers and t-storms are expected to develop across interior southern New England during the mid to late afternoon hours. A few storms may be contain brief heavy rain and locally strong wind gusts. The activity will weaken as it approaches the Boston to Providence corridor, but some may survive in a weakened form by early evening. SW wind gusts of 20 to 25 knots are expected to develop by afternoon but may be briefly stronger in any thunderstorm. Sunday night...High Confidence. Scattered showers and t-storms weaken as they approach the I-95 corridor during the evening. Otherwise, VFR except for perhaps some low clouds/fog in the evening across the Cape/Islands before the cold front crosses the region. SW winds early in the evening will shift to the northwest at 5 to 15 knots by late evening/overnight. KBOS TAF...High Confidence in TAF. Medium confidence in end time of sea-breeze this evening. KBDL TAF...High Confidence in TAF. Outlook /Monday through Thursday/... Monday through Tuesday: VFR. Breezy. Tuesday Night: VFR. Wednesday: Mainly VFR, with local MVFR possible. Slight chance SHRA. Wednesday Night: Mainly MVFR, with local VFR possible. Chance SHRA. Thursday: Breezy. Chance SHRA. && .MARINE... Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Tonight...High Confidence. Upper level ridging in place will keeps winds/seas below small craft thresholds tonight. However, main concern for mariners will be for fog re-developing mainly across our southern waters. Sunday and Sunday night...High Confidence. Southwest wind gusts of 20 to 25 knots will develop by Sunday afternoon ahead of an approaching cold front. Strongest of those winds will likely be near shore given better mixing over the land. It is marginal, but we may need some near shore small craft headlines in the afternoon for gusty winds/choppy seas. Winds shift to the northwest late Sunday night behind the cold front; with perhaps some more marginal small craft wind gusts of 20 to 25 knots. This time the strongest wind gusts will be over the open waters; so perhaps some marginal small craft headlines may be needed for a few or our eastern waters. Outlook /Monday through Thursday/... Monday through Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Tuesday: Winds less than 25 kt. Areas of seas approaching 5 ft. Tuesday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Wednesday: Winds less than 25 kt. Areas of seas approaching 5 ft. Wednesday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers. Thursday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain showers. && .CLIMATE... Daily record high temperatures... Sat May 21st... BOS 93F (1921) PVD 93F (1996) BDL 93F (1996) ORH 88F (1975) Sun May 22nd... BOS 93F (1959) PVD 94F (1941, 1992) BDL 95F (1992) ORH 90F (1911, 1992) Monthly record high temperatures... BOS 97F (05/26/1880) PVD 96F (05/26/2010) BDL 99F (05/26/2010, 05/20/1996) ORH 94F (05/26/2010) && .BOX WATCHES/WARNINGS/ADVISORIES... CT...Air Quality Alert until 11 PM EDT this evening for CTZ002. Heat Advisory until 8 PM EDT Sunday for CTZ002>004. MA...Heat Advisory until 8 PM EDT Sunday for MAZ003>006-010>018-026. RI...Air Quality Alert until 11 PM EDT this evening for RIZ001>008. Heat Advisory until 8 PM EDT Sunday for RIZ001>004. MARINE...None. && $$ SYNOPSIS...Frank/RM NEAR TERM...Frank/Gaucher/RM SHORT TERM...Frank LONG TERM...RM AVIATION...Frank/RM MARINE...Frank/RM CLIMATE...
Radar images courtesy Weather Underground / Intellicast.
UV Index forecast high for today: 8 Very 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:
0.02 in
Saturday:
0.66 in
May:
14.23 in
2022
44.2 in
Season Snow:
12:00am
69.4°F
High today:
12:00am
69.4°F
Low today:
4:50pm
85.6°F
High Saturday:
6:14am
58.8°F
Low Saturday:
12:00am
66.7°F
High dew pt today:
4:50pm
72.5°F
High dew pt Saturday:
4:50pm
92.2°F
High heat index Saturday:
None
Wind gust today:
12:04am
8 mph
Wind gust Saturday:
First Light:
4:44am
Sunrise:
5:17am
Sunset:
8:07pm
Twilight ends:
8:40pm
Daylight length:
14 hours 50 minutes
Phase:
Waning Gibbous (57%)
Moon rise:
1:50am
Moon set:
11:56am