FLUCTUATIONS FROM THE NORMAL TEMPERA- 

 TURE AND PRECIPITATION AT LOS ANGELES, 

 CALIFORNIA, DURING THE YEAR NINETEEN 

 THIRTEEN. 



By Ford A. Carpenter, LL. D., 

 Local Forecaster, U. S. Weather Bureau. 



The year 1913 will go down in the meteorological history 

 of the United States as one long to be remembered. Many 

 temoeratiire and rainfall records were equalled and exceeded 

 in Southern California, and especially in Los Angeles and 

 vicinity. The cause and character of the cold weather of 

 Tanuarv. the phenomenally heavy rainfall in February, and 

 the high temperatures in September, all form interesting 

 topics for study. These wide departures from the normal 

 suggest that there may be truth in the oft-repeated assertion 

 that there is a change in the climate, so at the close of this 

 paner will be found the author's views on the stability of the 

 climate. 



Taking up the three phases of unusual meteorological de- 

 partures from the normal chronologically, the first to be con- 

 sidered will be the extraordinarily low temperatures at the be- 

 ginning of the year 1913. 



The January Cold-Wave. 



The unusually cold weather of the first week in January, 

 1913, established new temperature records in nearly all por- 

 tions of California. In the citrus districts of Southern Cali- 

 fornia it will be remembered chiefly because of the damaging 

 efifect of the frost. From a close study of weather conditions 

 as shown by plant growth, horticulturalists as well as mete- 

 orologists are convinced that the low temperatures in South- 

 ern California on January 5, 6 and 7 have not been equalled 

 in some portions of this district for over a century. For ex- 

 ample, the century-old cactus hedge, planted by the early 

 mission fathers, at San Jacinto, California, was destroyed by 

 the cold weather in January. 



This portion of the Pacific coast is remarkably free from 

 atmospheric conditions which bring cold-waves. This is not 

 true of the region to the south and east, as a study of the tem- 

 perature records of Texas, Louisiana, Mississippi and Florida, 

 shows. The accompanying weather maps for January 6th and 

 7th, show the formation and growth of remarkable aerial 

 eddies and resultant temperatures. On the morning of the 

 seventh it will be observed that the dominating high area 

 produced zero temperatures far south into Arizona and dan- 



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