5-day weather forecast Boston Sep 12, 2026

25°14° · Sunny

Weather forecast Boston Saturday Sep 12, 2026: sunny, temperature from 14 °C to 25 °C.

Precipitation probability 26%. Wind up to 3.61 m/s (gusts 9.33 m/s). Air humidity 30–84%, atmospheric pressure 763–767 mm Hg, UV index up to 6.2.

Weather Alerts

MinorSep 8, 01:49 PM — Sep 9, 08:00 AMTranslate with Google

Small Craft Advisory issued September 8 at 1:49PM EDT until September 10 at 8:00PM EDT by NWS Boston/Norton MA

Small Craft Advisory

* WHAT...Southwest winds 10 to 20 kt with gusts up to 25 kt and waves around 2 feet expected. * WHERE...Boston Harbor. * WHEN...From 8 PM Wednesday to 8 PM EDT Thursday. * IMPACTS...Conditions will be hazardous to small craft.

Inexperienced mariners, especially those operating smaller vessels, should avoid navigating in hazardous conditions.

5 days at a glance — tap a day to open it

Sunrise 06:21
Sunset 18:59

New Moon3% illuminated
Moonrise 07:55 · Moonset 19:26

Chart

Table

← Fri, Sep 11

Sat, Sep 12, 2026

Forecast from 14 °C to 25 °C and precipitation

Temperature & Precipitation
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Temperature (°C)	16	16	16	15	14	15	14	14	16	18	20	23	23	24	25	25	24	23	20	19	18	17	16	16
Precipitation (mm/hr)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Cloud cover and precipitation probability

Cloud cover & Rain chance
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Cloud cover (%)	0	0	0	0	0	0	4	0	5	11	4	5	0	0	5	25	100	100	76	100	70	98	100	100
Rain chance (%)	1	1	3	1	2	3	5	5	2	1	1	1	1	0	1	2	10	10	9	12	7	15	23	26

Wind speed and direction

Wind & Wind gust
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Wind (m/s)	1.31	1.39	1.19	1.81	2.11	1.31	1	1	0.89	1.61	0.89	0.81	1.81	1.39	1.39	2	2.19	1.69	3.31	2.81	3.61	3.39	3	2.81
Wind gust (m/s)	1.72	1.81	1.31	2.61	3.61	1.42	1.83	1.81	1.19	2.03	1.22	2.61	2.14	2.64	2.72	2.89	3.53	4.14	5.11	7.11	9.33	9.33	8.94	8.72
Wind direction (°)	NNW 329°	NW 321°	NW 322°	NW 319°	NW 326°	NW 307°	SE 146°	SSE 147°	W 262°	WNW 296°	NW 309°	SW 218°	E 91°	E 98°	E 86°	E 83°	ESE 104°	SSE 159°	ESE 116°	S 184°	S 189°	S 190°	SSW 197°	SSW 196°

Air humidity

Humidity
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Humidity (%)	46	44	54	45	47	57	67	66	52	40	33	38	31	30	30	33	36	39	52	49	46	63	79	84

Atmospheric pressure

Pressure
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Pressure (mm Hg)	764	764	763	764	765	764	766	767	764	767	767	764	767	767	767	766	766	766	766	767	767	767	767	767

Ultraviolet index

UV Index
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
UV Index	0	0	0	0	0	0	0	0	0.6	1.7	3.2	4.8	6	6.2	5.5	4	2.4	1	0.3	0	0	0	0	0

Air quality & pollen

Air quality is available for the first three days only.

← Fri, Sep 11

Sat, Sep 12, 2026

Boston on the map

Data Sources & Methodology

Our weather forecasts are powered by a professional weather data provider that aggregates data from national weather services, satellite observations, radar networks, and over 80,000 weather stations worldwide. Forecast data is updated multiple times daily. We convert raw data into clear summaries — wind speed in m/s, pressure in mmHg — so you can plan your day with confidence.

Learn more about our methodology →