Paper 1 



Se^temttE ~ Ex t rat ro pi ca I storm activity in the North Atlantic 

 was Less frequent than usual this month because of a strong 

 (+13 mb anomaly) surface hiqh in this area. One storm/' bred in 

 the Denmark Strait/ brought England 4 inches of rain in 24 hours/ 

 with winds to 76 knots; it was the worst in 25 years but did not 

 break the drought as the water ran off the dry soil. 



In the Pacific, the surface pressure ^as louier than usual/ and 

 the high was displaced westward. The Aleutian low was 7 mb 

 deeper than normal/ sustaining strong westerly winds. Hurricane 

 Kathleen/ the first tropical cyclone to hit California in 

 37 years/ brought heavy rain to eight western States. Over 

 2 inches of rain fell in Death Valley/ ana in the San Joaquin and 

 Imperial Valleys crop losses were severe. 



The mean 7CG mb circulation showed a three-lob ed pattern/ with 

 closed lows over the Alaska Peninsula/ Baffin Island/ and Franz 

 Josef Land. Strong zonal westerlies persisted over the Pacific 

 north of 4GiM. The trouqh deepened off California and the 

 downstream riage lay over the Rockies. The trough over eastern 

 North America deepened. The persistent ridge over Europe 

 retrograded and a trough became established over Scandinavia and 

 the British Isles/ extending toward the Azores. 



October - host of the North Atlantic storms occurred in the 

 second half of the month/ following the historical tracks from 

 the Gulf of St. Lawrence to south of Iceland or from the 

 U.S. east coast to northern Europe. The pressure centers were 

 near their long-term mean locations/ but were more intense than 

 normal. A trough extended from a -12 mt anomaly center over 

 Land's End southeastward across France. A high north of the 

 olack Sea ridqed to a +14 mb anomaly over northern Norway. 

 Surface pressure on the North Atlantic west of 5CW was within 

 1 mb of the climatological mean. 



There were fewer storms than normal in the Gulf of Alaska. They 

 originated farther east and south than usual and tracked toward 

 British Columbia. The pressure pattern resembled the long-term 

 mean/ but with a counterclockwise shifting of centers. There was 

 a -6 mb anomaly center near SDK/ 175W/ ana a +7 mb anomaly center 

 south of Si t ka . 



At 700 mb the Aleutian low persisted over Bristol Bay/ but the 

 Pacific subtropical high/ and consequently the area of strong 

 zonal westerlies/ retrograded 30 deg of longitude from its 

 position of the previous month/ and a strong ridge developed over 

 Kamchatka. The upper air pattern in this area was tighter than 

 normal/ and wind flow was more intense. The mean trough over the 

 eastern Pacific intensified/ the ridge over the Rocky Mountains 

 persisted/ and the trouqh over the eastern United States 

 deepened. A Large area of negative height anomaly/ with a -127 m 



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