California lettuce supplies should tighten later this fall, as Salinas finishes early and fewer growers ship from Huron.

Growing weather in the late summer and early fall had been volatile enough as it was through early October — then a hot streak hit, said Mark McBride, salesman for Salinas, Calif.-based Coastline Produce.

Temperatures topped 100 degrees in some areas — and stayed in the high 60s or low 70s at night — during the hot spell, which lasted three or four days, McBride said.

“That combination doesn’t do anything good for crops. It reduced some yields immediately, and I expect to see more going forward. It’s been a crazy year.”

Seed stem and puffier heads are among the risks associated with abnormally hot growing weather, McBride said.

Tip burn, scalding and even some mildew also have affected plants, said Jason Lathos, commodity manager for Salinas-based Church Bros. LLC.

“You’ve seen a checklist of defects on iceberg,” Lathos said. “Everyone’s had a bit of everything.”

What concerns Lathos more than quality, however, is how much Mother Nature has pushed up the Salinas deal.

“We were seven, then 10, then 14 days ahead of schedule. We’ve gotten good at pushing fields to handle the small gaps, but when you’re talking about multi-week — we’re not that good.”

As a result, the deal will likely gap at the end of October, as the Huron deal ramps up for Church Bros. and others in late October.

“We’re in uncharted waters. It’s never been like this in Salinas.”

And with fewer growers planting lettuce in the Huron region, which bridges the Salinas and desert deals for many, because of water shortages, Salinas will have to stretch even further this year, which could be complicated by the difficult growing weather, McBride said.

“There’s a certain amount of risk this time of year — there are only so many weeks left. There are just a few left in Huron. That’s been greatly reduced in past years. The rest of us are going later in Salinas and starting earlier in the desert.”

Coastline expects to kick off its Yuma, Ariz., desert deal about Nov. 10. Salinas will likely wrap up the same week.

“There may be a bit of overlap,” McBride said.

With the up-and-down weather, McBride said markets could easily have strengthened significantly — but they haven’t.

“Demand has been steady. I’m kind of surprised we haven’t seen more of a reaction and higher prices.”

But McBride said he’s fine with that. When prices get too high, shoppers can get turned off, sending demand in the other direction.

“They’re still at consumer-friendly prices.”

On Oct. 7, the U.S. Department of Agriculture reported prices of $15-16.56 for film-lined cartons of iceberg 24s from Salinas, up from $12.56-13.75 on Sept. 30, 2013. October prices were not issued in 2013 because of the government shutdown.