No trick, tonight marks the end of Daylight Saving Time here in California. (Actually, the official time is 2AM Sunday…)
Don’t forget to turn your clocks back one hour before you go to bed.
And a treat for family safety. October is Fire Prevention Month, so “fall back” time is a good reminder to change the batteries in your smoke detectors and carbon monoxide alarms. I also stick a small label on each alarm with the date I installed a new battery, as another reminder.
Saturday morning, I’m headed up to the Condor Lookout to replace the weather station with a new one. This should make the data more reliable on the web page. Look for it to be back sometime Saturday afternoon (Halloween).
An area of low pressure centered over southern Nevada/northern Arizona combined with a 1036 millibar Eastern Pacific high about 600 miles off the southern Oregon coastline will produce a very steep pressure gradient along the northern and central coast of California.
Consequently, moderate gale to fresh gale (32-46 mph) northwesterly winds with gusts near 50 mph will develop along the coastline later today. Wind speeds in the coastal valleys and interior will reach strong to gale force (25-38 mph) levels with gust as high as 45 mph by this afternoon.
Note: Condor Lookout weather station on Hi Mountain in the Los Padres National Forest – which has an elevation of 3,190 feet – may see wind gust more than 60 mph.
Today’s high temperatures will be as much as 20 degrees cooler than yesterday’s and well below seasonal normal’s. Temperatures will range between the high 50s along the coast to the low to mid 60s in the coastal valleys and interior under hazy sunshine.
http://www.sanluisobispo.com/682/story/888467.html
The storm that hit the Central Coast on Tuesday was unlike any other October storm since records have been kept, with many one-day rainfall records for the month broken, especially in the northern part of San Luis Obiso County.
The last time we received over an inch of rain in one day in October occurred on Oct. 19, 2004, when a cold front passed over San Luis Obispo County.
The Diablo Canyon Ocean Lab rain gauge recorded 1.5 inches of precipitation in just six hours.
On Monday, we saw a storm developing in the eastern Pacific; later that day it would further intensify before moving toward British Columbia.
This low-pressure system produced a steep pressure gradient along the West Coast with the surface charts showing the isobar lines tightly spaced together.
The southerly winds in many locations, especially in the northern part of the county, reached over 50 mph.
And on the newly installed Condor Lookout weather station on Hi Mountain in the Los Padres National Forest — which has an elevation of 3,190 feet — wind gusts reached 85 mph.
The associated warm front arrived on Tuesday morning producing a steady rain.
The rain continued over the next 24 hours as another very-slow-moving weather front from the west passed our area.
It was hard to call this a cold front because there wasn’t really any cold air associated with this system, and there wasn’t much of a wind shift.
Feeding into this weather system were the remnants of former superTyphoon Melor that had slammed into Japan earlier in the month.
The upper-level charts indicated an extremely strong jet stream centered directly over the Big Sur coastline.
This jet acted like a conveyor belt, bringing in tropical moisture from the eastern Pacific.
The south to southwesterly winds pushed air masses higher as they hit the coastal mountains, causing more rain to fall.
Meteorologists call this “orographic enhancement.”
Farther south in the county, the rainfall totals slowly decreased.
The San Luis Obispo County Water Resources rain gauge on the top of Rocky Butte near San Simeon recorded 13.7 inches of rain.
E-mail that I received from readers reported between 7 and 10 inches along Highway 41 between Morro Bay and Atascadero.
I had one report of 10.5 inches in See Canyon.
The SLOweather.com rain gauge in the hills near Los Osos Valley Road and Foothill Boulevard recorded 7.7 inches, while Cal Fire Station 15 — the former South Bay Fire Department in Los Osos —recorded 5.2 inches.
The Diablo Canyon Ocean Lab rain gauge recorded 2.5 inches; further south in Nipomo the San Luis Obispo County Water Resources rain gauges ranged from 1.1 and 2.4 inches.
Nacimiento Lake went from 9 percent of capacity to 18 percent in 24 hours. That’s what I call a rainstorm.
This week’s forecast
Saturday morning’s northeasterly (offshore) winds produced warm and clear weather along the coastline and in the coastal valleys, while fog and mild temperatures developed in the interior.
The winds shifted out of the northwest (onshore) yesterday late morning producing cooler temperatures and giving relief to many soccer players.
A weak cold front will brush Northern California this morning with a few rain showers.
The main effect of this cold front along the Central Coast will be increasing northwesterly (onshore) winds along with variable mid to high-level clouds today.
The onshore flow will bring night and morning coastal low clouds and fog along with cooler temperatures.
Another, stronger weather system will push through Northern California on Monday and will bring rain as far south as the Bay Area.
As this cold front moves down the California coastline on Monday it will produce gentle and variable winds, a deep marine layer, drizzle and mild temperatures throughout our area.
The cold front will be followed by increasing northwesterly winds on Tuesday.
High pressure is expected to develop over the Great Basin late Tuesday producing gentle to moderate (8-18 mph) northeasterly(offshore) winds during the night and morning hours, followed by fresh to strong (19-31 mph) northwesterly winds along the shoreline during the afternoon hours.
This condition will lead to mostly sunny skies and above seasonable temperatures along the beaches and in the coastal valleys, while the interior could see areas of night and morning fog and cooler temperatures, a reversal of what normally transpires between the coastline and interior during spring and summer months.
Surf and sea report
This morning’s 4- to 6-foot northwesterly (300-degree deep-water) sea and swell (with a 5- to 11-second period) will become a 4- to 5-foot northwesterly swell (with an 8- to 11-second period) on Monday.
Increasing northwesterly winds will produce a 5- to 6-foot northwesterly (300-degree deep-water) sea and swell (with a 4- to 11-second period) on Tuesday through Wednesday.
A 968 millibar storm is forecast to develop 2,000 miles to the west of Oregon on Monday.
A 2-to-4-foot west-northwesterly (285-degree deep-water) swell (with a 20- to 22-second period) is forecast to arrive along our coastline late Wednesday, building to 10 to 12-feet (with a 16- to 18-second period) on Thursday.
This west-northwesterly swell will decrease to 8 to 10 feet on on Friday, followed by another increase in northwesterly swell next weekend.
Arriving from the southern hemisphere, a 1 foot southern hemisphere (245-degree deep-water) swell (with an 18-20 second period) will arrive along our coastline on Monday, increasing to 1 to 2 feet (with a 16-18 second period) on Tuesday through Wednesday.
Conservation tip
Use compact fluorescent lamps. You can lower your electric bills by converting to energy-efficient low-wattage compact fluorescent lighting.
To learn more, visit www.wecandothis.com.
John Lindsey is a media relations and nuclear communications representative for Pacific Gas and Electric Co. He is also a meteorologist who specializes in forecasting for San Luis Obispo County. Send him questions to pgeweather@pge.com.
You may have noticed that the outside weather from the Condor Lookout is, to be charitable, off. The inside temperature, humidity, barometric pressure, and battery voltage are all fine.
This indicates that the Davis Vantage Pro console which is connected to the WeatherElement interface is functioning, but is not receiving data transmissions from the outdoor Integrated Sensor Suite. That unit may have been damaged in the storm Tuesday evening.
We’ll know more as soon as someone returns to the site.
At 6 AM PDT Wednesday, in the 25 hours since the storm started, SLOweather has recorded a WHOPPING 7.51″ of rain! Also, wind gusts to 40 yesterday afternoon here and 85 (!) at the condor lookout station.
You can somewhat see the effect of orographic enhancement on rain totals across town. 2 miles east at the SLO City WRF, the storm total is 4.88, and 2 miles beyond that, at the Islay Hill station, 4.52″ and the PG&E Community center on Ontario Road, only 2.60″.
It usually takes several storm events to get any runoff here, but in 12 hours, the local creeks went from bone dry to raging.
(2:30 PM Monday, I fixed the bad links in this post.)
I’m sure you know by now of the unseasonably strong storm headed our way for tonight, Tuesday and Wednesday, There’s the potential for 1-4 inches of rain, and high winds.
Just in time for the storm, SLOweather.com, in affiliation with WeatherElement.com, is pleased to add the Condor Lookout’s weather station to our affiliates. Saturday, Katie and I took part in their annual work day, and installed a WeatherElement.com cellular Internet interface on the Lookout’s Davis Vantage Pro weather station. It’s updating every 30 seconds right now, and the link to the temporary data display is here.
John Lindsey, the NWS and my own WxSim forcast are all forecasting a change in the weather pattern and chance of rain early to mid week next week.
I’ll be out this weekend cleaning and checking my rain gauges, and replacing batteries in the wireless units.
I can see an accumulation of spider webs and dirt in my 4″ Stratus gauge, so I know they all need a little TLC before the winter rains. We have 4 gauges at SLOweather, 2 Davis Vantage Pro 2s, the 4″ Stratus gauge, and an “official” antique 8″ Standard Gauge.
Saturday’s full Harvest Moon rises locally in SLO at 6:13 PM PDT, a half hour before sunset at 6:43 PM PDT.
It truly becomes full just shy of 5 hours after it rises, at 11:10 p.m. Pacific Daylight Time.
Other names for this full moon are the Blackberry Moon, and the Blood Moon.