Point Forecast: 2 Miles WSW Portola Valley CA  37.37N 122.25W (Elev. 1473 ft)	Last Update: 5:07 am PDT May 19, 2025

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Weather Elements Weather/Precipitation Temperature (°F) Dewpoint (°F) Heat Index (°F) Surface Wind  ktmphkm/hm/s Sky Cover (%) Precipitation Potential (%) Relative Humidity (%) Rain Thunder Fog Trans. Wind  ktmphkm/hm/s 20ft Wind  ktmphkm/hm/s

48-Hour Period Starting: 7am Mon, May 19 20258am Mon, May 19 20259am Mon, May 19 202510am Mon, May 19 202511am Mon, May 19 202512pm Mon, May 19 20251pm Mon, May 19 20252pm Mon, May 19 20253pm Mon, May 19 20254pm Mon, May 19 20255pm Mon, May 19 20256pm Mon, May 19 20257pm Mon, May 19 20258pm Mon, May 19 20259pm Mon, May 19 202510pm Mon, May 19 202511pm Mon, May 19 202512am Tue, May 20 20251am Tue, May 20 20252am Tue, May 20 20253am Tue, May 20 20254am Tue, May 20 20255am Tue, May 20 20256am Tue, May 20 20257am Tue, May 20 20258am Tue, May 20 20259am Tue, May 20 202510am Tue, May 20 202511am Tue, May 20 202512pm Tue, May 20 20251pm Tue, May 20 20252pm Tue, May 20 20253pm Tue, May 20 20254pm Tue, May 20 20255pm Tue, May 20 20256pm Tue, May 20 20257pm Tue, May 20 20258pm Tue, May 20 20259pm Tue, May 20 202510pm Tue, May 20 202511pm Tue, May 20 202512am Wed, May 21 20251am Wed, May 21 20252am Wed, May 21 20253am Wed, May 21 20254am Wed, May 21 20255am Wed, May 21 20256am Wed, May 21 20257am Wed, May 21 20258am Wed, May 21 20259am Wed, May 21 202510am Wed, May 21 202511am Wed, May 21 202512pm Wed, May 21 20251pm Wed, May 21 20252pm Wed, May 21 20253pm Wed, May 21 20254pm Wed, May 21 20255pm Wed, May 21 20256pm Wed, May 21 20257pm Wed, May 21 20258pm Wed, May 21 20259pm Wed, May 21 202510pm Wed, May 21 202511pm Wed, May 21 202512am Thu, May 22 20251am Thu, May 22 20252am Thu, May 22 20253am Thu, May 22 20254am Thu, May 22 20255am Thu, May 22 20256am Thu, May 22 20257am Thu, May 22 20258am Thu, May 22 20259am Thu, May 22 202510am Thu, May 22 202511am Thu, May 22 202512pm Thu, May 22 20251pm Thu, May 22 20252pm Thu, May 22 20253pm Thu, May 22 20254pm Thu, May 22 20255pm Thu, May 22 20256pm Thu, May 22 20257pm Thu, May 22 20258pm Thu, May 22 20259pm Thu, May 22 202510pm Thu, May 22 202511pm Thu, May 22 202512am Fri, May 23 20251am Fri, May 23 20252am Fri, May 23 20253am Fri, May 23 20254am Fri, May 23 20255am Fri, May 23 20256am Fri, May 23 20257am Fri, May 23 20258am Fri, May 23 20259am Fri, May 23 202510am Fri, May 23 202511am Fri, May 23 202512pm Fri, May 23 20251pm Fri, May 23 20252pm Fri, May 23 20253pm Fri, May 23 20254pm Fri, May 23 20255pm Fri, May 23 20256pm Fri, May 23 2025

Date	05/19																	05/20
Hour (PDT)	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06
Temperature (°F)	54	56	59	62	65	68	69	69	70	68	67	65	62	58	56	55	53	53	52	50	49	49	48	49
Dewpoint (°F)	42	44	45	46	46	49	50	50	52	51	50	49	48	47	46	45	45	45	44	43	42	42	41	41
Heat Index (°F)
Surface Wind (mph)	8	9	9	10	11	11	11	13	14	15	16	18	18	18	14	9	8	9	9	9	9	9	7	7
Wind Dir	N	N	N	N	N	N	NNW	NW	WNW	WNW	WNW	WNW	WNW	WNW	WNW	W	W	W	W	WNW	W	W	WNW	W
Gust			18	20	20	20	20	18	21	24	25	30	32	33	34	31	30	29	28	26	22	21	18
Sky Cover (%)	8	3	3	2	2	2	2	1	1	2	4	3	7	12	15	11	11	15	14	14	14	16	16	11
Precipitation Potential (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Relative Humidity (%)	64	63	60	55	51	51	51	51	53	54	55	57	61	65	68	70	73	73	74	75	77	77	77	75
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date																		05/21
Hour (PDT)	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06
Temperature (°F)	50	51	54	57	58	61	63	64	64	64	62	60	57	54	52	51	50	50	49	49	48	47	47	48
Dewpoint (°F)	42	43	44	44	44	45	46	47	47	46	45	44	43	42	42	42	41	41	41	40	40	39	39	39
Heat Index (°F)
Surface Wind (mph)	7	6	6	7	7	7	7	10	10	10	11	11	11	9	9	9	7	7	7	6	6	6	3	3
Wind Dir	W	NW	NW	WNW	WNW	WNW	WNW	WNW	WNW	WNW	W	W	W	W	W	W	W	W	W	W	W	W	NW	NW
Gust
Sky Cover (%)	14	15	8	6	4	4	4	2	2	2	5	5	5	6	6	6	6	6	6	6	6	6	7	7
Precipitation Potential (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Relative Humidity (%)	74	73	67	62	58	55	54	54	53	53	54	57	61	65	68	70	72	73	73	73	73	73	72	72
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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