This is a breaking news update, previous story below. Stay with ABC7 for the latest on this developing news.
A fierce summer storm packed a punch overnight, bringing a non-stop lightning show to all parts of the Bay Area. But firefighters say all that lightning combined with extreme heat sparked multiple fires.
RELATED: Rare thunderstorms hit Bay Area, with lightning filling the sky amid heat wave
"All the six fires we had were caused by lightning," said East Contra Costa Fire Marshal Steve Aubert.
Those fires grew into the "Deer Zone Fire" in East Contra Contra County. As of Sunday afternoon, the fire had burned 300 acres and was 0% contained.
Ryan Bell and his family live on Morgan Territory Road, where residents were being urged to prepare to evacuate if needed.
"It's constantly a fire concern here, plenty of dry vegetation. We try to keep a fire break across the property," Bell said.
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In Livermore, Alameda County Fire units worked to contain a vegetation fire in Sycamore Park, likely sparked by lightning. The fire was stopped at 50 acres.
CAL FIRE tweeted, "responded to 11 fires since 1 a.m. in Santa Cruz and San Mateo Counties. Most presumed to have started from lightning strikes. Forward progress has been stopped on most of these fires, we're working to get more resources, stretched thin due to heavy fire activity."
Contra Costa County firefighters needed help too.
"We need choppers but demand is high around the state," said Aubert.
The heat on Sunday was intense for firefighters.
RELATED: Lightning, rare thunderstorms hit Bay Area sparking fires and causing power outages
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Take a look at the dozen of fires sparked by lightning across the Bay Area below:
EAST BAY
In the East Bay, Livermore crews are battling the Arroyo Fire that's holding at 50 acres and is 50% contained.
Crews were battling another vegetation fire at Sycamore Grove Park in Livermore. The fire was stopped at approximately 50 acres with no injuries.
Contra Costa Fire says multiple agencies are fighting several fires in Morgan Territory, off Marsh Creek Road which is being called the Deer Zone Fire. Four fires are burning 325 acres, officials say.
Fire officials say two of the smaller fires have been contained but the larger one has burned nearly 100 acres. They say all of the fires were sparked by lightning around 6 a.m.
VIDEO: Timelapse video shows Deer Zone fire burning in East Bay
Timelapse video shows Deer Complex fire burning in East Bay
Contra Costa CWS tweeted that CAL FIRE is warning residents living on the upper portion of Morgan Territory Rd. to prepare to evacuate.
Officials say no evacuation has been ordered at this time, however, it is possible one may become necessary.
Contra Costa Co. Fire is advising people there is a lot of smoke in the area and to not call 911 to report the smell of smoke.
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CAL FIRE SCU tweeted that crews have been battling 8-10 different fires throughout the unit since 3 a.m. Sunday.
SOUTH BAY/PENINSULA
In the South Bay, CAL FIRE CZU tweeted crews responded to 11 fires since 1 a.m. (7 in Santa Cruz Co, 4 in San Mateo Co). Most presumed to have started from lightning strikes.
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Crews in San Jose responded to a 2-alarm apartment fire that was sparked by lightning. Fire officials were able to quickly put out the fire and contain it to one unit.
Crews are also battling the Marsh Fire on Arroyo Hondo Road and Oakridge Road in Santa Clara County. The 585-acre blaze is made out of 3 fires, officials say.
NORTH BAY
In Marin county, firefighters say lightning started a fast moving grass fire which came dangerously close to an apartment complex in Corte Madera.
Crews are working several small lightning fires. Smoke Is visible on Mount Tam below Throckmorton Station.
Crews are also responding to a possible lightning caused fire by Devils Gulch Fire Road near Samuel P. Taylor State Park. No evacuation orders or warnings are in place.
The National Weather Service has extended the Bay Area's Red Flag Warning until Monday morning.
In a tweet, NWS said more thunderstorms are expected to develop and lightning strikes will likely lead to new fire starts.
Stay with ABC7 News for the latest details on this developing story.
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