Today’s the first day of summer.

And to mark it, Mother Nature is rolling out the first heat wave of the year featuring five consecutive days of 100-degree plus days.

It starts today with the National Weather Service predicting a high of 103 degrees.

While daily  temperatures will pass the century mark through Saturday, the highest two days are expected to be Friday and Saturday with a high of 104 degrees.

It is expected to dip down to a high of 99 degrees by Sunday.

The highs will stay in the mid to high 90s through June 30. After that they will peak in the low 90s before jumping back into the mid-90s with a high of 96 on the Fourth of July. Temperature peaks are expected to stay in the mid to high 90s through the end of July flirting within a degree or two of 100 degrees during the final six days of July.

To escape the heat, you’ll have to head to the coast or the Sierra crest.

San Francisco is not expected to breach 70 degrees through Saturday. It will be a tad warmer in Santa Cruz with the high reaching into the mid-70s.

Yosemite Valley at 3,966 feet won’t offer much of a respite. The highs there are expected to be in the high 80s and low 90s until Sunday when it may get as hot as 101 degrees.

Sonora Pass at 9,623 feet will top off in the mid-70s. The tradeoff is on Thursday, Friday and Saturday there is a change of afternoon thundershowers.

This week will be the first extended heat wave test of California’s precarious power grid.

It also will be the first heat wave where peak demand pricing is in effect Monday through Friday from 4 to 9 p.m. when the temperature is at the highest as is power demand.

The California Public Utilities Commission pushed PG&E and other utilities to up the kilowatt hour cost during peak hours in a bid to prevent heavy demand from forcing power outages.

In the San Joaquin Valley air conditioning makes up the lion’s share of summer energy consumption. That means the switch to time-of-use rate plans can led to higher PG&E bills.

New rate plans increase the price of electricity during peak hours from 4 to 9 p.m. Off-peak hours from 9 p.m. to 4 p.m. have lower rates. The peak pricing applies to use Monday through Friday and only a few holidays.

If you don’t manage — essentially reduce — electricity use during peak hours — you can see a sizeable jump in your PG&E based on comparable usage from last summer.

Peak power demands during heat waves and extremely hot days such as the 103-degree high forecast for today push available supplies to the limit last summer in California

Even without a blistering heat wave during peak use hours this summer between 4 and 9 p.m. weekdays, models cited by the CPUC, California Energy Commission, and the California Independent System Operator show the Golden State has a solid chance of coming up short 1,700 megawatts.

Based on historic use, power may need to be cut to 1.3 million California households. That translates roughly to 4 million people or a tenth of all Californians possibly being without electricity.

The situation was not created by PG&E or other power providers.

Instead, it is by the inability for the regulatory mandated shift to green power to keep up with demand.

The three agencies have noted if wildfires, a heat wave, drought conditions, smoky/cloudy skies, and winds all align the shortfall could easily hit 5,000 megawatts. That translates into 3.75 million homes.

The rates charged are higher during the peak period in an effort to encourage consumers to shift their electric load to off-peak hours when electricity is cheaper.

Regulations dictate 100 percent carbon-free electricity by 2045 with the attached benchmark of being 60 percent by 2030.

The state has pushed hard to force the plug to be pulled on additional carbon-based power as well as nuclear power to the tune of 6,000 megawatts by 2025.

Manteca cooling

center opens today

Due to high temperatures, the Manteca Cooling Center at the Manteca Transit Center, 220 Moffat Blvd, will open today from 1 to 9 p.m.

Activation of the Cooling Center is subject to change as weather conditions change.

The cooling center is being opened to help Manteca residents stay cool during potentially dangerous hot weather expected though Saturday. If you know anyone who needs shelter from the heat, you are asked to relay this information.  

Bottled water will be available. Masks will be provided if needed.

Do not go to the cooling center if you have a fever, if you have been exposed to or are exhibiting symptoms of COVID-19, or if you have been ordered to quarantine or isolate.

E-mail mantecacwc@mantecagov.com with any questions or concerns.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com

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