Rainfall totals for Calif

reefuss12

New member
Tony. Can you give the statistics for rainfall in the month of May for Calif. for the last 20 - 30 years or so. Is this the wettest May? This latest storm seems like a record breaker. Or is it.
 
LA averages 0.31 inches rain in May. Only 11 out of 141 years have had as much as an inch. Current May is probably less than 1/4 inch so far with perhaps 1/2 inch possible between now and Sunday.

The 3 highest years:
1921, 3.57 inches
1998, 3.10 inches, http://bestsnow.net/19980514baldytc.HTML
1977, 3.03 inches
Baldy still had a base from the big El Nino when that storm hit in 1998, thus the powder morning referenced above. 1977 was the infamous western drought year, yet that May storm was substantial. It rained out 2 Dodger games (there have only been 17 rainouts since Dodger Stadium opened in 1962). Baldy opened for a weekend on about 3 feet from that storm. I was a dumb beginner, went up there on May 14 with no sunscreen and blistered my nose.

SF averages 0.59 inches rain in May. 28 out of 169 years had an inch or more. The 3.92 inches in 1998 is second highest to 4.02 inches in 1925.

May 1977 only rained 0.57 in SF but it definitely was widespread snow in the Sierra. It snowed 40 inches at the Central Sierra Snow Lab, second highest to 44 inches in 2010 since 1969. Mammoth did not record May snow back then, but I've seen Memorial Day most often quoted as 1977 closing day. I've also seen April 10 listed, which I suspect was true (only 90 inches snowfall Nov-Apr) but Mammoth then likely reopened from the May storm. I found data from a WRCC station in the White Mountains that got 50 inches snow in May 1977.

From Mammoth's own records the highest May totals are 38 inches in 2011 and 31 inches in 2005. Mammoth might get 1-2 feet from the upcoming 2 storms. Mammoth's May average is 11.6 inches, has only received 1.5 inches so far this May.
 
From https://www.mercurynews.com/2019/05/16/ ... ay-totals/

"Cities that eclipsed their monthly averages in the past 24 hours include Kentfield (1.48 inch average in May) and Santa Rosa (1.28-inch average in May)." Kentfield had 1.57" and Santa Rosa 2.17".

"On average, San Francisco receives .70 inches of rain in the month of May, while Oakland receives .77 inches and San Jose .51 inches. Before this current storm, the last time San Francisco, San Jose or Oakland recorded more than one-quarter of an inch of rain in May was 2011."

While SF had .53 and San Jose .36 yesterday, other locations in N CA had 1.5 to 5" and more is expected through early next week.
 
The storm dropped 4-18 inches at Squaw and 13 inches at Mammoth Main Lodge. Downtown LA had 0.48 inches rain. There are two more smaller storms forecast tonight and Tuesday.

Both CSSL and Mammoth average 11 inches May snow, so Mammoth is just above average now. Mammoth rates to finish May at least double average but still well short of record high. Per Mammoth Forum there were a lot of slides up top Friday.
 
Baldy got a few inches last night. Be nice if this cycle stays like this for the next 10 years. Thx for the stats.
 
Back
Top