![National Oceanic and Atmospheric Administration](/build/images/header/noaa.d87e0251.png)
![National Weather Service](/build/images/header/nws.4e6585d8.png)
![United States Department of Commerce](/build/images/header/doc.b38ba91a.png)
Area Forecast Discussion
Issued by NWS Boston, MA
Issued by NWS Boston, MA
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
475 FXUS61 KBOX 190201 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 1001 PM EDT Thu Jul 18 2024 .SYNOPSIS... Broad area of high pressure to build into Southern New England through Friday evening. This will bring significantly lower humidity levels compared to the past several days, along with dry weather and seasonable temperatures. Chances for showers and storms along with increased humidity return next week with timing still uncertain. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 10PM Update: Surface high pressure continues to build in behind the cold front that brought all the showers and thunderstorms last evening. Dewpoints are already dropping into the upper 50s to low 60s for much of SNE. With clear skies and calm winds overnight, low temps are still on track to drop into the upper 50s to low 60s. 315 PM Update: Drier NW flow is starting to take root across Southern New England. Although still pretty humid over the Cape and Islands (e.g. dewpoints in the upper 60s to low 70s) with a few showers dotting the southern nearshore waters, look across western and central MA and most of northern CT and you`ll find dewpoint temperatures crashing into the upper 50s to lower 60s. Thus, a FAR more refreshing airmass is gradually filtering into the entirety of Southern New England as high pressure is ridging in from the west. Tranquil evening in store for Southern New England, and overall a really nice midsummer evening is on tap. Dewpoints should commonly dip into the 50s (which many individuals would describe as comfortable on the humidity scale, and it`s been a long time coming over where we`ve been for the past week-plus). We could see a bit of a freshening to NW breezes early tonight but should settle in around 5-10 mph for the late evening and overnight. While decent radiational cooling is anticipated under clear skies and though many areas saw rain yesterday, the combo of falling dewpoints and enough of a northwest breeze should mitigate fog or mist development. Lows tonight in the upper 50s/around 60 in the interior, with lower to mid 60s for eastern MA and RI. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... 315 PM Update: High pressure remains in control of our weather to close out the workweek. Full sun, dry weather, seasonable temps and comfortable humidity levels are on tap, setting the stage for a spectacular midsummer day to kick off the weekend. Easing NW winds on Friday gives way to seabreezes along both coasts following the typical start timing climatology around late morning to early afternoon. Clear skies and light winds for the evening could allow for patchy fog development Friday night in the favored river valleys, and there is some increase in moisture levels along the immediate south coast Friday night so areas along the south coast could be another potential development spot. Highs on Friday in the mid 80s inland, upper 70s near the coast. Lows in the mid 50s to lower 60s on Friday evening. But certainly far more tolerable from a humidity perspective. && .LONG TERM /SATURDAY THROUGH THURSDAY/... The weekend continues to look dry and pleasant with high temperatures in the mid to upper 80s across the area. Dewpoints through the weekend are expected to remain in the 60s. Not much in terms of rain or storm chances through Sunday, but CAPE values of 100-200 J/kg in northern and northwestern MA could help encourage some very isolated showers. Saturday looks relatively cloudy with skies mostly clearing going into Sunday afternoon. Winds over the weekend look mostly calm with a possible seabreeze moving in Sunday afternoon across Boston and NE MA. Winds on Monday and Tuesday look pretty calm but variable throughout the day with another chance at a seabreeze in the afternoons for the same areas. SW flow aloft looks to return going into next week, bringing with it increased moisture and chances for showers and storms. Guidance is suggesting greater chances for showers and storms from Wednesday night into Thursday, though there isn`t much confidence in the timing just yet due to the spread between the ensembles and deterministic models still present. CSU ML probs currently have SNE under a 0.05-0.15 chance for severe on Wednesday and Thursday, so this will be something to continue to monitor. Temperatures throughout the week are looking to remain in the 80s for most of the area, aside for a slight dip into the upper 70s for parts of central into eastern MA and most of RI. Even past this, there are possible severe chances on Thursday into Friday; the GFS in particular has a trough progressing from the Great Lakes into Vermont and New Hampshire, bringing with it CAPE values from 120-400 J/kg across SNE and continued strong SW flow. The ECMWF keeps this trough in the Great Lakes region through the end of this period for the time being. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight...High confidence. VFR. Winds initially out of the WNW, but shift to the NW around 10 kts. Could briefly gust to 20 kts through roughly 03Z, but should decouple and settle in around 5-10 kt for overnight. Friday and Friday Night: High confidence. VFR. Easing NW winds during the day on Friday. Localized sea breezes developing roughly 15-17Z. Light winds for Friday evening. KBOS TAF...High confidence in TAF. VFR through the period. Seabreeze Fri starting 15-17Z. KBDL TAF...High confidence in TAF. VFR through the period. Outlook /Saturday through Tuesday/... Saturday through Monday: VFR. Monday Night: VFR. Slight chance SHRA, isolated TSRA. Tuesday: VFR. Chance SHRA, isolated TSRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Through tonight: High confidence. Winds diminishing, SW becoming NW then N Thu night behind the front. Seas over south coastal waters will be 5-6 feet today, diminishing overnight. Showers and a few t-storms continue into the early afternoon, especially southern waters. Friday: High confidence. Winds 5-10 kts. Seas 2-4 feet. Outlook /Saturday through Tuesday/... Saturday through Monday: Winds less than 25 kt. Monday Night: Winds less than 25 kt. Slight chance of rain showers. Tuesday: Winds less than 25 kt. Chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 2 PM EDT Friday for ANZ254>256. && $$ SYNOPSIS...Loconto/Hrencecin NEAR TERM...Loconto/KP SHORT TERM...Loconto LONG TERM...Hrencecin AVIATION...Loconto/BL/Hrencecin MARINE...Loconto/Hrencecin