306 H. Gibbons on the Climate of San Francisco for 1855. 
to west before sunrise, and bringing showers of rain and hail 
through the day. 
The first week of January was cold and rainy. On the 6th 
the mercury fell to 33°, the coldest weather of the entire winter. 
Snow was visible on the coast mountains. For the remainder of 
the month the sky was almost cloudless, and the temperature 
moderate, ranging from 49° to 59° at noon, until the 20th, after 
which the range was from 60° to 72°—the highest point reached 
by the thermometer in January since the commencement of my 
observations in 1850. The warmest morning in the month was 
57° and the coldest noon 48°. The mean temperature at sunrise 
was 44°71, at 9 a. m. 499-39, at noon 57°-29, at 10 vp. m. 469°87, 
Mean of extremes 51°-00. Proportion of clear sky 69 per cent. 
Thirteen days were entirely or nearly clear, and five entirely 
cloudy. Four foggy mornings. Rain fell on nine days, quantity 
4:52 in. Winds NW and N nineteen days, NE and E one day, 
SE and S seven days, SW and W four days. Land winds 65 
per cent., sea winds 35. High winds on two days. Light breezes 
on twenty-nine days. 
Mean of barometer: sunrise 29°869 in., 9 a. m. 29885 in., 
noon 29°860 in., Hep p. Mm. 29°867 in. Maximum 30-12 in., min- 
imum 29:40 in 
oe or two slight frosts occurred. The winds were very ight, 
seldom rising op abe a moderate breeze. "They prevailed from 
N and NW, and South. On the 19th and 20th a brisk gale from 
the north swept over the entire State, attended with a falling 
barometer, and followed by heavy rains, which by this time 
were much needed. An unusual quantity fell, Pie — month. 
The thermometrical means were, at sunrise 50°-25. mu. 55°°04, 
noon 63°-29, 10 p. mM. 52°°'32. Mean of acmtrernes: "56° Ya 
72°, and the minimum 41°, Warmest morning 56°, coldest 
noon 56°. Proportion of clear sky 60 per cent. Whole days 
clear thirteen, cloudy five. Fog on two mornings and one 
evening. Rain on nine days; oti 4 4-64 in. Winds N and 
ric means, “sunrise 29:849, 9a. m. 29° 857, noon, "29-936, 
10. m. 29850. Extremes 30:06 and 29°48. 
arch.—Mean temperature at sunrise 519-77, 9 a. M 67°81, 
sie 67°-03, 10 p. wm. 53°-68. Mean of extremes, 59°-40. High- 
Pe ‘temperature 78°, lowest 44°. Warmest morning 5 
oon 69°. “Proportion of clear sky 53 percent, cloudy 47. Only 
iver days were clear from morning to night, and four were 
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