Big Change Ahead


500 millibar map (about 20,000 ft) for 7:00 p.m. CDT October 18
This weekend will mark the start of a significant change in the weather pattern across the U.S
Right now the eastern half of the country is chilly as a large upper low spins over the area. Out west, it has been very warm recently under an upper level ridge. Temperatures, for example, in northern California have been in the upper 80s and low 90s. Yesterday new high temperature records were set in San Francisco and Oakland.




RECORDS SET...

 LOCATION                NEW RECORD   OLD RECORD AND YEAR
 --------------------------------------------------------
 SAN FRANCISCO AIRPORT     86           85         1988
 OAKLAND DOWNTOWN          87           84         1974
 OAKLAND AIRPORT           87           83         1974
 MOUNTAIN VIEW             89           87         1995


A number of daily temperature records have been set in southern California as well. On Wednesday El Cajon reached 102°F, breaking the old record of 96°F set in 1996.

As this weekend progresses, the pattern will shift as the upper low lifts out of the Midwest, and a strong trough develops off the west coast.

Forecast 500 millibar map for 7:00 a.m. CDT Sunday, October 21.

What's this mean? Well, the central and eastern U.S. will enjoy a period of mild fall weather. October so far has been cooler than normal from the Rockies eastward, and near to above normal west of the Rockies.


The west coast, from Washington south through northern California, will be in for a period of stormy, cool weather.



Do you have a question you would like answered or suggestions on topics you would like to see in future blog posts?  Feel free to email me your questions and suggestions at hberg74@gmail.com

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