42.2120, -71.1140

1. Sat2 PM56°97%28 mph
2. 3 PM56°98%28 mph
3. 4 PM56°98%28 mph
4. 5 PM56°99%26 mph
5. 6 PM57°99%24 mph
6. 7 PM56°99%23 mph
7. 8 PM56°100%21 mph
8. 9 PM55°100%21 mph
9. 10 PM56°100%22 mph
10. 11 PM56°100%22 mph
11. Sun12 AM57°100%21 mph
12. 1 AM57°100%21 mph
13. 2 AM57°100%20 mph
14. 3 AM57°100%20 mph
15. 4 AM57°100%21 mph
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17. 6 AM58°98%22 mph
18. 7 AM58°97%23 mph
19. 8 AM59°94%24 mph
20. 9 AM59°92%24 mph
21. 10 AM60°92%23 mph
22. 11 AM60°92%23 mph
23. 12 PM61°91%22 mph
24. 1 PM61°93%22 mph
25. 2 PM61°94%21 mph
26. 3 PM61°94%20 mph
27. 4 PM60°95%20 mph
28. 5 PM60°95%18 mph
29. 6 PM60°95%17 mph
30. 7 PM59°94%16 mph
31. 8 PM59°94%15 mph
32. 9 PM60°98%15 mph
33. 10 PM60°98%16 mph
34. 11 PM59°97%16 mph
35. Mon12 AM59°98%16 mph
36. 1 AM59°99%15 mph
37. 2 AM59°98%15 mph
38. 3 AM58°99%15 mph
39. 4 AM58°99%15 mph
40. 5 AM58°96%15 mph
41. 6 AM58°90%15 mph
42. 7 AM59°81%14 mph
43. 8 AM59°79%14 mph
44. 9 AM60°85%14 mph
45. 10 AM61°92%15 mph
46. 11 AM62°99%15 mph
47. 12 PM62°98%14 mph
48. 1 PM62°98%13 mph

Scroll sideways for more hours. Pick an hour for every number.

1. TodaySep 2659°53°Patchy Fog100%1.49 inwind 28 mph · gusts 46 mph
2. SunSep 2764°57°Patchy Fog100%3.08 inwind 24 mph · gusts 44 mph
3. MonSep 2862°55°Rain Showers99%1.14 inwind 16 mph · gusts 23 mph
4. TueSep 2965°55°Slight Chance Rain Showers then Mostly Cloudy63%0.01 inwind 7 mph · gusts 14 mph
5. WedSep 3071°57°Partly Sunny3%wind 3 mph · gusts 9 mph
6. ThuOct 175°60°Mostly Sunny3%wind 8 mph · gusts 16 mph
7. FriOct 274°57°Partly Sunny13%wind 9 mph · gusts 18 mph
8. SatOct 368°53°24%wind 7 mph · gusts 13 mph
9. SunOct 468°54°National Blend40%0.22 inwind 8 mph · gusts 16 mph
10. MonOct 565°47°National Blend39%0.46 inwind 8 mph · gusts 17 mph
11. TueOct 661°46°National Blend13%0.10 inwind 8 mph · gusts 15 mph
12. WedOct 7~62°47°Model mean
13. ThuOct 8~61°52°Model mean0.11 in
14. FriOct 9~61°52°Model mean0.02 in
15. SatOct 10~61°46°Model mean
16. SunOct 11~71°56°Model mean

• Feels like56°
• WindENE 28 mphgusts 39 mph
• Radar over this pointno reading
• Humidity90%
• Dew point53°
• Pressure—
• UV index—
• Air quality—
• Visibility2.3 mi
• Sunrise and sunsetSunrise · Sunset
• Moonrise6:22 PMMoonset 6:27 AM
• Moon phaseFull moon100% lit

NOAA’s weighted blend of every model it runs, to eleven days, with the chances the grid above does not carry. Where the local office’s grid reaches, its figure sits beneath the blend’s; where it does not, the blend stands alone.

1. TodaySep 2661°55°NWS grid 59° / 53°rain 100%thunder 25%wind 21 mph · gusts 40 mph
2. SunSep 2765°57°NWS grid 64° / 57°rain 100%thunder 39%1.98 inwind 21 mph · gusts 35 mph
3. MonSep 2865°55°NWS grid 62° / 55°rain 99%thunder 19%0.80 inwind 13 mph · gusts 22 mph
4. TueSep 2968°55°NWS grid 65° / 55°rain 27%0.01 inwind 6 mph · gusts 13 mph
5. WedSep 3073°57°NWS grid 71° / 57°rain 8%wind 3 mph
6. ThuOct 175°59°NWS grid 75° / 60°rain 10%wind 8 mph · gusts 16 mph
7. FriOct 275°56°NWS grid 74° / 57°rain 13%wind 9 mph · gusts 18 mph
8. SatOct 369°54°NWS grid 68° / 53°rain 22%wind 6 mph · gusts 12 mph
9. SunOct 468°54°Beyond the NWS gridrain 40%0.22 inwind 8 mph · gusts 16 mph
10. MonOct 565°47°Beyond the NWS gridrain 39%0.46 inwind 8 mph · gusts 17 mph
11. TueOct 661°46°Beyond the NWS gridrain 13%0.10 inwind 8 mph · gusts 15 mph

Each line is one model’s own forecast at its own grid cell: three kilometers for HRRR, a quarter of a degree for the global models, which can sit a few hundred meters above or below the town. Where they agree the forecast is settled; where they part is where it is not.

NWS gridBlendHRRRGFSGEFS ± spreadECMWFECMWF AI

A ~ marks a high or low read from six-hourly steps, which miss the true extreme by a degree or two.

ECMWF ensemble meteogram

10 daysTemperature plume

No forecast has skill day by day past about two weeks, and this page does not print one. Where the models stop, the calendar takes over: the 1991 to 2020 normal for each date, the record high and low ever set on it, and where the Climate Prediction Center leans warm, cool, wet or dry over the coming weeks, the month and the season. A site that shows a high for a date three months out is showing you this normal with a wobble.

The forecast reaches Sun Oct 11, from the NWS grid, then the National Blend, then the mean of the global models. Beyond it the lines are the calendar.

Forecast high and lowNormal high and lowRecord high and lowCPC leans warmer than normal

None of these is a measurement. Each is a rating of the forecast ahead, and of what is happening at the point right now, against what the activity or the ailment is known to mind, and each names the figure that decided it. An ailment or a pest is rated as a risk, low to extreme; an activity, a chore or a journey as a condition, poor to ideal.

Each rating says which span it is for: the rest of today’s daylight, tonight, or the next 24 hours.

Tonight has no dark, clear hour without a bright moon in this forecast. Rated poor.

The last night runs past the end of the forecast and is rated on the hours it covers.

Dark is the sun 18 degrees below the horizon; where it never gets that low, 12 degrees, marked nautical. Clear is sky cover of 20% or less. A bright moon is one above the horizon with a quarter or more of its disc lit. Transparency in the table is estimated from surface humidity (70% and 85% mark fair and poor) and visibility, since the forecast carries no haze or high cloud moisture. Seeing and transparency by hour, where shown, are Environment and Climate Change Canada’s astronomy forecast (regional model; seeing from cloud, wind shear, turbulence near the ground and the surface temperature trend; transparency from the moisture through the whole air column), under the Open Government Licence - Canada. Dew is the air within 2 °C of its dew point. Excellent is four or more clear moonless hours with good transparency; good is three; fair is one, or two clear hours.

Golden hour is the sun between 6 degrees above the horizon and 4 degrees below it; blue hour is the sun between 4 and 6 degrees below. These are the definitions timeanddate.com and PhotoPills use. Directions are degrees clockwise from true north, where the sun’s upper edge and the moon’s center cross a flat horizon; hills and buildings change both. None means the sun does not reach that height on the day; all day means it stays inside the band.

This hour: no-fly (ground wind near or over your limit, wind at 400 ft near or over your limit, gusts near or over your limit, chance of rain, visibility under 3 miles (107.51), thunderstorms possible). No stretch of two good hours in the next three days.

Today: civil twilight for Part 107 6:06 AM to sunrise 6:36 AM, and sunset 6:35 PM to 7:05 PM. Anti-collision lighting is required in those minutes and at night.

Good Caution No-fly

Flight restrictions nearby

Reading the FAA’s temporary flight restrictions.

Flight restrictions on the map. TFRs are not the whole picture: controlled airspace around airports needs LAANC authorization. Check the FAA’s B4UFLY.

Wind at 400 ft is estimated from the 10 m forecast by the power law, with exponents for each Pasquill stability class (Irwin 1979, rural, as in EPA dispersion models; the class from wind, sun height and cloud, after Turner 1970); gusts keep the ground gust’s margin. Caution from three quarters of your limit; the default 24 mph is the wind resistance printed for common sub-250 g drones. 14 CFR 107.51: “The minimum flight visibility, as observed from the location of the control station must be no less than 3 statute miles” and at least “500 feet below the cloud”. 14 CFR 107.29: “No person may operate a small unmanned aircraft system during periods of civil twilight unless the small unmanned aircraft has lighted anti-collision lighting visible for at least 3 statute miles”; civil twilight is the 30 minutes before sunrise and after sunset, in Alaska the Air Almanac’s. Kp: SWPC’s scales say satellite navigation problems may occur at G3 (Kp 7) and navigation is “degraded for hours” at G4 (Kp 8); Kp 5 is the typical app warning. Typical limits, not rules: rain chance 30% caution and 60% no-fly, thunder 10% and 20%, below 0 °C caution and −10 °C no-fly, over 40 °C caution. Your drone’s manual and the airspace come first.

Hours fit for spraying, and the days dry enough for fieldwork and hay, read from this forecast’s wind, gusts, humidity, temperature and rain.

Spraying windows

• Wed 1 PM to 8 PM 7 hours, every hour within the rules
• Thu 11 AM to 2 PM 3 hours, every hour within the rules
• Thu 4 PM to 9 PM 5 hours, every hour within the rules
• Fri 8 PM to Sat 12 AM 4 hours, every hour within the rules
• Sat 9 AM to 5 PM 8 hours, every hour within the rules

Good Marginal No

Field days

Spraying: sustained wind 3 to 10 mph, the range US extension services and most labels give; gusts no more than 15 mph (this page’s limit); delta T (air minus wet-bulb temperature) 2 to 8 °C preferred and 8 to 10 °C marginal, from GRDC guidance, with the wet bulb by Stull’s formula; no hour at a 30% chance of rain or 0.25 mm forecast during the rain-free time. Follow the product label, which overrides all of this. Field days: dry is no daytime hour at a 30% chance and under 1 mm all day, wet is 6 mm (0.25 in) or more; soil moisture is not in the forecast, so ground still wet from earlier rain is not accounted for. Hay drying marks a dry day with humidity down to 50% and a breeze of 5 mph or more.

The best-rated day this week is Saturday, rated best.

Periods in bold fall within an hour of sunrise or sunset. The weather’s side is the fishing index

Major periods are two hours centered on the moon’s passage overhead and underfoot; minor periods are one hour centered on moonrise and moonset: the conventional durations of John Alden Knight’s solunar tables (1936). The rating is this site’s: one point to start, two more within a day and a half of a new or full moon (one more within three and a half days), and one more when a period falls within an hour of sunrise or sunset. The theory has mixed support in fisheries research; the times are exact astronomy.

1. This Afternoon59° · 99% · NE 28 mph

   Patchy fog and showers and thunderstorms. Cloudy, with a high near 59. Northeast wind around 28 mph, with gusts as high as 46 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

2. Tonight55° · 100% · NE 20–24 mph

   Patchy fog and showers and thunderstorms. Some of the storms could produce heavy rain. Cloudy, with a low around 55. Northeast wind 20 to 24 mph, with gusts as high as 45 mph. Chance of precipitation is 100%. New rainfall amounts between 2 and 3 inches possible.

3. Sunday64° · 98% · NE 18–24 mph

   Patchy fog and showers and thunderstorms before 2pm, then patchy fog and showers and thunderstorms. Some of the storms could produce heavy rain. Cloudy, with a high near 64. Northeast wind 18 to 24 mph, with gusts as high as 44 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.

4. Sunday Night57° · 99% · NE 17 mph

   Patchy fog and showers and thunderstorms before 2am, then patchy fog and showers and thunderstorms. Cloudy, with a low around 57. Northeast wind around 17 mph, with gusts as high as 33 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

5. Monday62° · 99% · NE 12–15 mph

   Rain showers and patchy fog. Cloudy, with a high near 62. Northeast wind 12 to 15 mph. Chance of precipitation is 100%.

6. Monday Night55° · 93% · N 5–13 mph

   Rain showers. Cloudy, with a low around 55. North wind 5 to 13 mph. Chance of precipitation is 90%.

7. Tuesday65° · 15% · N 3–7 mph

   A slight chance of rain showers before 7am. Mostly cloudy, with a high near 65. North wind 3 to 7 mph.

8. Tuesday Night55° · 4% · NW 2 mph

   Mostly cloudy, with a low around 55. Northwest wind around 2 mph.

9. Wednesday71° · 1% · W 3 mph

   Partly sunny, with a high near 71. West wind around 3 mph.

10. Wednesday Night57° · 3% · SW 3 mph

    Mostly cloudy, with a low around 57. Southwest wind around 3 mph.

11. Thursday75° · 2% · SW 3–8 mph

    Mostly sunny, with a high near 75. Southwest wind 3 to 8 mph.

12. Thursday Night60° · 8% · SW 7 mph

    Partly cloudy, with a low around 60. Southwest wind around 7 mph.

13. Friday74° · 8% · W 6–9 mph

    Partly sunny, with a high near 74. West wind 6 to 9 mph.

14. Friday Night57° · 16% · NW 5–8 mph

    A slight chance of rain showers after 2am. Mostly cloudy, with a low around 57. Northwest wind 5 to 8 mph.

Written by the forecaster on duty for their own colleagues and for anyone who wants to know why the forecast says what it says. It is not edited for the public, so it uses the office’s shorthand; it is also the most honest thing any weather service publishes.

The national centers each publish a judgment the local grid does not carry. Read here at this exact coordinate.

The last spring freeze (32°F) usually comes around April 18 and the first fall freeze around October 26: a growing season of about 190 days.

One fall in ten brings a freeze by October 9; one spring in ten still has one after April 30.

Climate of 42.21, -71.11: normals, records and every month

The forecast office edits about sixty fields for every cell of its grid. The common ones are above; these are the rest, as the daily extreme, for anyone who needs the mixing height, the fire danger or the swell.

Each forecast day against the same calendar date at the nearest long-record station: the 1991 to 2020 normal, and the record high and low with the year they were set.