Port Costa, CA Current Weather Conditions

Current weather observations and 72-hour history for Port Costa, CA. • View 5-Day Forecast ›

▼Current Conditions — Port Costa, CA

NAPA (KAPC)

Cloudy

55.4 F

Humidity:	94%
Wind Speed:	W 10.4 mph
Barometer:	29.94 in
Dewpoint:	53.6 F
Visibility:	10.00 mi
Precip:	--
Heat Index:	NA
Wind Chill:	NA

Sep 21 2026, 11:30 PM PDT

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▼Hourly Observation History — Port Costa, CA

Time	Wind (mph)	Vis (mi)	Weather	Precip (in)	Temperature (F)		Relative Humidity	Wind Chill (F)	Heat Index (F)	Pressure
Time	Wind (mph)	Vis (mi)	Weather	Precip (in)	Air	Dwpt	Relative Humidity	Wind Chill (F)	Heat Index (F)	altimeter (in)	sea level (mb)
11:30 PM PDT	W 10.4	10.00	Cloudy	--	55.4	53.6	94%	NA	NA	29.94	1013.9
11:20 PM PDT	W 10.4	10.00	Cloudy	--	55.4	53.6	94%	NA	NA	29.94	1013.9
11:15 PM PDT	W 8.1	10.00	Cloudy	--	55.4	53.6	94%	NA	NA	29.94	1013.9
11:10 PM PDT	W 6.9	10.00	Cloudy	--	55.4	53.6	94%	NA	NA	29.94	1013.9
11:00 PM PDT	NW 6.9	10.00	Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:50 PM PDT	9.2	10.00	Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:45 PM PDT	8.1	10.00	Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:40 PM PDT	6.9	10.00	Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:30 PM PDT	W 9.2	10.00	Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:25 PM PDT	9.2	10.00	Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:15 PM PDT	W 8.1	10.00	Cloudy	--	57.2	55.4	94%	NA	NA	29.95	1014.2
10:10 PM PDT	6.9	10.00	Mostly Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
10:05 PM PDT	8.1	10.00	Mostly Cloudy	--	57.2	55.4	94%	NA	NA	29.95	1014.2
10:00 PM PDT	SW 6.9	10.00	Mostly Cloudy	--	57.2	53.6	88%	NA	NA	29.95	1014.2
09:50 PM PDT	SW 8.1	10.00	Mostly Clear	--	57.2	53.6	88%	NA	NA	29.95	1014.2
09:40 PM PDT	10.4	10.00	Mostly Clear	--	57.2	53.6	88%	NA	NA	29.95	1014.2
09:35 PM PDT	SW 9.2	10.00	Clear	--	55.4	53.6	94%	NA	NA	29.95	1014.2
09:20 PM PDT	SW 8.1	10.00	Mostly Clear	--	57.2	53.6	88%	NA	NA	29.95	1014.2
09:15 PM PDT	SW 9.2	10.00	Mostly Clear	--	57.2	53.6	88%	NA	NA	29.95	1014.2
09:05 PM PDT	SW 8.1	10.00	Partly Cloudy	--	57.2	53.6	88%	NA	NA	29.94	1013.9
09:00 PM PDT	SW 8.1	10.00	Partly Cloudy	--	57.2	55.4	94%	NA	NA	29.94	1013.9
08:50 PM PDT	SW 10.4	10.00	Clear	--	57.2	53.6	88%	NA	NA	29.94	1013.9
08:45 PM PDT	SW 10.4	10.00	Clear	--	57.2	53.6	88%	NA	NA	29.94	1013.9
08:40 PM PDT	SW 11.5	10.00	Clear	--	57.2	53.6	88%	NA	NA	29.94	1013.9
08:35 PM PDT	SW 10.4	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.94	1013.9
08:30 PM PDT	10.4	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.94	1013.9
08:25 PM PDT	12.7	10.00	Mostly Clear	--	59.0	55.4	88%	NA	NA	29.93	1013.5
08:15 PM PDT	13.8	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.93	1013.5
08:10 PM PDT	11.5	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.93	1013.5
08:05 PM PDT	15.0	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.93	1013.5
08:00 PM PDT	17.3	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.93	1013.5
07:55 PM PDT	17.3	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.92	1013.2
07:50 PM PDT	17.3	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.92	1013.2
07:45 PM PDT	16.1	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.92	1013.2
07:40 PM PDT	17.3	10.00	Clear	--	59.0	55.4	88%	NA	NA	29.92	1013.2
07:25 PM PDT		10.00	Clear	--	59.0	55.4	88%	NA	NA	29.92	1013.2
07:20 PM PDT		10.00	Clear	--	59.0	55.4	88%	NA	NA	29.92	1013.2
07:10 PM PDT	18.4	10.00	Clear	--	60.8	55.4	82%	NA	NA	29.91	1012.9
07:05 PM PDT	17.3	10.00	Clear	--	60.8	55.4	82%	NA	NA	29.91	1012.9
07:00 PM PDT	17.3	10.00	Clear	--	60.8	55.4	82%	NA	NA	29.91	1012.9
06:50 PM PDT		10.00	Clear	--	60.8	55.4	82%	NA	NA	29.91	1012.9
06:45 PM PDT	16.1 G 21.9	10.00	Clear	--	60.8	55.4	82%	NA	NA	29.91	1012.9
06:35 PM PDT	S 17.3 G 25.3	10.00	Clear	--	60.8	55.4	82%	NA	NA	29.90	1012.5
06:25 PM PDT	19.6	10.00	Clear and Windy	--	62.6	55.4	77%	NA	NA	29.90	1012.5
06:15 PM PDT	17.3	10.00	Clear	--	62.6	55.4	77%	NA	NA	29.90	1012.5
06:05 PM PDT	S 19.6	10.00	Clear and Windy	--	62.6	55.4	77%	NA	NA	29.90	1012.5
06:00 PM PDT	18.4 G 24.2	10.00	Clear	--	62.6	55.4	77%	NA	NA	29.89	1012.2
05:50 PM PDT	19.6	10.00	Clear and Windy	--	62.6	55.4	77%	NA	NA	29.89	1012.2
05:45 PM PDT		10.00	Clear	--	62.6	55.4	77%	NA	NA	29.89	1012.2
05:40 PM PDT	G 27.6	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
05:35 PM PDT	S 17.3	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
05:30 PM PDT	S 17.3 G 24.2	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
05:25 PM PDT	S 16.1 G 21.9	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
05:10 PM PDT	G 27.6	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
05:05 PM PDT	17.3	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
05:00 PM PDT	S 18.4	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
04:50 PM PDT	S 18.4 G 25.3	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.90	1012.5
04:40 PM PDT	16.1	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
04:30 PM PDT	18.4	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.90	1012.5
04:25 PM PDT	18.4	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.90	1012.5
04:20 PM PDT		10.00	Clear	--	64.4	55.4	73%	NA	NA	29.90	1012.5
04:10 PM PDT	18.4	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
04:05 PM PDT		10.00	Clear	--	64.4	55.4	73%	NA	NA	29.90	1012.5
04:00 PM PDT	18.4	10.00	Clear	--	66.2	55.4	68%	NA	NA	29.89	1012.2
03:50 PM PDT	S 17.3	10.00	Clear	--	64.4	55.4	73%	NA	NA	29.89	1012.2
03:40 PM PDT	19.6	10.00	Clear and Windy	--	66.2	55.4	68%	NA	NA	29.90	1012.5
03:30 PM PDT	17.3	10.00	Clear	--	66.2	55.4	68%	NA	NA	29.90	1012.5
03:25 PM PDT		10.00	Clear	--	66.2	55.4	68%	NA	NA	29.90	1012.5
03:20 PM PDT		10.00	Clear	--	66.2	55.4	68%	NA	NA	29.90	1012.5
03:05 PM PDT	15.0	10.00	Clear	--	66.2	55.4	68%	NA	NA	29.91	1012.9
03:00 PM PDT	16.1	10.00	Clear	--	66.2	55.4	68%	NA	NA	29.91	1012.9
02:50 PM PDT	17.3	10.00	Mostly Clear	--	66.2	55.4	68%	NA	NA	29.91	1012.9