Golden Gate Weather Services

For the past 5 months, the Oceanic Niño Index (ONI) has been stuck in the middle of the Weak El Niño category (i.e., +0.50 and +1.0) and the models are keeping it in that range through the end of the year!  Going back to 1950 (https://ggweather.com/enso/oni.htm) there are only three back-to-back years with kind of similar patterns, but none close enough in my estimation to be reasonable analogs. They were 1968-69 to 1969-70, 1986-87 to 1987-88, and 2014-15 to 2015-16.  California precipitation patterns related to El Niño years can be found at https://www.ggweather.com/ca_enso/ca_elnino.html. 


 


Current SST Temperatures with Niño Region insets


Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather

After well above normal February and March rainfall, percentages in April across most of California dropped to well below normal. However, season-to-date numbers are still mostly above normal, and in many locations their seasonal (July 1 to June 30) normals have already been reached. See https://ggweather.com/seasonal_rain.htm and https://ggweather.com/water/.





Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather

“ STORM” by George R. Stewart, should be REQUIRED READING if you are a meteorologist, meteorology student, deal with or communicate California weather, anyone whose day-to-day activities in California are impacted by the weather or just a weather enthusiast. I have just finished rereading it for probably the 5^th time and couldn’t put it down.

I first read “Storm” when I was an NWS meteorologist intern in 1975 and identified with one of the characters in the book, the Junior Meteorologist (JM) at the Weather Bureau in San Francisco. Over the years, I have given or loaned copies to over a dozen friends and colleagues and even though it was written in 1941, the meteorology is still sound and incredibly insightful. Likewise, the impact of a storm across California for 12 days in a winter where there had been early talk of a drought resonates strongly with this year’s headlines. Interwoven throughout the book are the interactions between the weather, the utilities, railroads, commerce, the airlines and people, which are just as relevant today as they were almost 80 years ago.



Please, do yourself a favor and track down a copy. It’s in many libraries, plus I often find copies squirreled away in used bookstores and there are numerous versions available on Amazon and now on AUDIBLE. (When you finish “Storm”, read Stewart’s “Fire” which looks at another timely topic, the impact of a wildfire in the Sierra Nevada.)

Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather 

How did the 2018-2019 Winter Outlooks that were issued last fall compare with reality? This year, in addition to looking at the CPC forecasts, several outlooks from the private sector were added for comparison. In all of the outlooks I see big-time errors; begging the question is there "skill" and "value" in these products? See http://ggweather.com/cpc/2019/


Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Phone: (408) 379-7500
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather

2018-2019 CALIFORNIA WATER BY THE NUMBERS

It's should be no surprise that abundant rainfall this season has translated into a pretty bright picture for water supplies across the Golden State. 

The latest Drought Monitor shows California with its least amount of drought-impacted area since 2011. With only 0.60% in the Moderate Drought category (D1) and 9.56% in D0 (Abnormally Dry), California is at its most drought free since 8-30-2011. 

 The latest California Precipitation Snapshot shows rainfall already approaching or above normals for the entire is rainfall season (July 1 to June 30).

Of particular note is the 8-Station Northern Sierra Index, with state's largest reservoirs, which is now at 128% of normal and just 2.33" shy of their seasonal normal of 54.52".

  
And all of the above translates into California reservoir levels close to or exceeding historical averages for this time of year. 


Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather

Historically, February 5th is the snowiest day of the year in San Francisco and the Bay Area. Of the 11 days when snow has been recorded near sea level in San Francisco, twice before on February 5th. In 1887 and again in 1976. (https://www.ggweather.com/sf/snow.htm)


The event on February 5, 1887, was the snowiest on record with over 3 inches in the downtown area of the City.  This is well documented in Mark McLaughlin's wonderful  "San Francisco Snowstorms" document (http://thestormking.com/Sierra_Stories/San_Francisco_Snowstorms/san_francisco_snowstorms.html)


And the last time there was an accumulation of snow near sea level in San Francisco was on February 5, 1976, with up to an inch downtown and 5" on Twin Peaks. (Spectacular photograph below: Art Frisch, SF Chronicle), 



The forecast conditions for tomorrow, February 5, 2019, do NOT look like a repeat of either one of the previous snow events. But the combination of much colder air moving into the region and continued bands of showers overnight should at least whiten the hills above 2000' and in some areas, especially inland possibly down to into the 1000' to 1500' range.

Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather

The first 16 days of January have seen great rainfall recoveries across California from recent storms. Most locales have jumped by about 20% versus their Jan. 1st %-of-normal numbers. The very important 8-Station N Sierra Index (8SI) has jumped to 89% of normal while both Redding and Sacramento are now just above normal. For others see below or https://www.ggweather.com/water/.

Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather



 

With no rain in the forecast through the end of the year, here are some updates on where California stands precipitation-wise. Most of the state north of the Tehachapis is about 75% of normal, while to the south it is averaging from near to slightly above normal.

Through Dec 31, San Francisco will be at 5.95 inches or 65% of normal. This is the 63rd driest out of the 170 seasons dating back to 1849. Looking at the 30 seasons that had this value plus/minus an inch, the corresponding end of the rainfall season (Jul 1 through Jun 30) totals ranged from 11.06" to 27.86". This breaks down further with 6 seasons at < 60% of normal, 11 seasons at 61-80% of normal, 8 seasons at 81-100% and 5 seasons in the 100 to 120 percent of normal. 

https://www.ggweather.com/water/
 





Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Email: jnull@ggweather.com
Web: http://ggweather.com
Twitter: @ggweather