September 18, 2018 at 10:07 am

October 2018 Looking to Have Rain Events for Southern California; Offshore Flow Last Week Of September?

by
1K+Shares

Rain?  What is that?  Water from the sky I say?  Many Southern Californians forget what the sight of rain is and when it comes it is a welcomed sight from paradise lost.  Many Octobers have gone without normal rainfall, but this one may not.  Read on for details.

Things will be pretty uneventful through the rest of the month, given we are in the hands of a dry offshore trough.  Most of the thunderstorm activity this week will be in Arizona, where I expect a number of thunderstorms to form.  Monsoon Season ended on the 15th of September so the Arizona event will be just a tropical moisture influx.  Sometimes events in September are pretty severe and it is also the best time to see a tornado so if in Arizona on Wednesday along I-10 and I-40 west of PHX/FLG then you could get a chance to see one.

The heatwave during the last week of September is weighing in right now on 50/50.  Changes in the Fall atmosphere are starting to show and this is when many longer range numbers start to get confused.  A long-wave trough diving in from Canada for the Central and Eastern United States.  This would mean that a ridge offshore Oregon and Washington would be responsible for this and thus the mean wind flow will be northwest to southeast with the low level flow being from northeast to southwest.. or.. a Santa Ana Wind Pattern.  Some of these numbers do show this.. and in turn elevated temperatures and fire risks.

Ongoing Ad Until End Month – The Southern California Weather Force has a member section with rain, wind, thunder, tornado etc models that are personally updated by me with each Santa Ana Wind or storm event.  You also can get e-mailed alerts via a slew of micro-climates.  Usually $50 a year the price has nearly been cut IN HALF as the discount that will go through till the end of September 2019.  This is a yearly discount that I do so if you are a monthly contributor of $5 or $6.50 then I would upgrade to this and do it yearly each fall and you’ll save more. 
Deal ends at the end of this month (September) so Click Here To Join or Upgrade Via The Member Section
Please remember if upgrading to CANCEL YOUR PAYPAL PAYMENTS. Login and cancel the reoccurring payments.

Some of the numbers do not and maintain with the warmer temperatures being during the first week of October.  Averaging all of them together does support the trough dropping into the West Coast during the last week of September, between 9/25 and 9/28 .. for elevated temps with an offshore wind pattern.  It however does not look like a major Santa Ana Wind Event.  Should this trough drop along the coast instead we would not get the heat+fire danger and maintain a cooler than average September thus far.

Longer range shows rainfall gradually being possible through October where last year we had 0.10″ of rain in Downtown Los Angeles in October.  This year the ‘average’ for my numbers is predicting a preliminary 0.6″ of rain, which is 5x more than last season and around normal for the month.  What we do not want to see between now and most of October is a major ridge forming and shoving storms east of here into Arizona, missing us.  This type of blocking pattern is similar to last year and we do not want to see that early in the season.  That is something I will be watching very carefully as we near the first storm.  First actual storm is slated between October 6th and the 25th should trends continue.  We do not want a pattern for weakening fronts as it hits down here while OR/Northern CA get slammed.  This will seal the fate of the coming season so fingers crossed.

This last rainfall season (2017-2018) was the driest for Los Angeles since 2006-2007 and the third driest since rainfall records began being kept in 1877.  Anything is going to be better than what we had last year and that was a La Nina year.. so fairly typical of a year for last season.  This season so far is maintaining neutral/weak El Nino and some of our best and worst seasons have come from that.  Best being 2004-2005 and worst being 2006-2007.  At the moment it is truly anyone’s guess which way we will head so I am reserving the final forecast for sometime in October when my final long range numbers come in as I needed Spring/Summer 2018’s numbers to complete the forecast on what type of season we will get.

EMAIL ALERTS?  Many micro-climate zones to choose from to get custom alerts from thunderstorm, wind, flood, surf, heat, cold, storm, and much more with the premium e-mail alert system, the most advanced zone alert system in Southern California – Click Here To Join!

SOUTHERN CALIFORNIA ONLY:  if it does not say “Liked”  LIKE The Page Below and join thousands of informed weather forecast viewers in our region for more of the updates! noticeable

BEHIND THE SCENES FORECASTS/UPDATE PAGE:  if it does not say “Liked”  LIKE The Page Below and join thousands of informed weather forecast viewers in our region for more of the updates! noticeable

VISIT THE MEMBER SECTION FOR 2017-2018 SEASON  – SIGN-UP OR READ ABOUT IT HERE AND GET ADVANCE UPDATES DURING WEATHER EVENTS THROUGH THE ADVANCED EMAIL ALERT SYSTEM FOR MICRO-CLIMATE ALERTS ISSUED HERE!

Click Here To Find Me On TWITTER.

Comments are closed.

wp_footer();