Summer waiting for Modesto's May rains to end

If April showers bring May flowers, what do May showers bring?

Though the spate of cool April and May weather is delaying the growth and harvest of some plants, many are enjoying the more bearable late-spring temperatures.

The continuation of moderate temperatures throughout the Northern San Joaquin Valley also means residents aren't using much air conditioning or heating, which equates to reduced utility bills.

That could continue with the likely return of showers today and a lingering chance of rain through Friday, said National Weather Service forecaster Johnnie Powell.

Once the storm system passes through, temperatures should reach the low 70s by Friday and low 80s by Monday, making the Memorial Day weekend warmer, but not too hot.

"It makes it nice to have summer delayed a bit," said Powell, noting that summer officially begins June 21.

He said it's rare to have showers this late in May and that it's hard to tell if the next few days will be the last rainy days of spring. Seven years out of 10, the rain has stopped by this time, he said.

Monday's high temperature topped out at 70 degrees. Last year, May 24 reached 76, according to Melissa Williams, spokeswoman with the Modesto Irrigation District.

In 2009, May averaged 71 degrees. With seven days left, May is averaging 63 degrees this year.

MID officials have noticed a dip in power demand this year, Williams said, citing the cooler weather and economy as likely reasons.

"We've had a slow start to the irrigation season due to the cool, windy and wet conditions," Williams added. "Irrigation demand is fairly low right now."

Farmers have reported scattered delays in winter crop harvesting, said Milton O'Haire, Stanislaus County's assistant agricultural commissioner-sealer.

Some have seen more apricots than usual drop off trees, he said, and some cherries, which are sensitive this time of year, are splitting because of too much water.

"It's nothing really major, but we're looking at a little bit more rain, so we'll look out if that will cause any problems," O'Haire said.

For home gardeners, experts advise patience with seasonal fruits and vegetables such as tomatoes, squash, beans, melons, peppers, herbs and lettuce, many of which have been planted.

The lower temperatures will slow growth but are not deadly. Plants are in danger only when overnight temperatures near freezing, said Ed Perry, farm adviser at the Stanislaus County University of California Cooperative Extension. The lows this week are forecast to be close to 50.

"Plants will continue to grow, and (low) temperatures for a lot of vegetables aren't bad," Perry said.

Gardeners should watch for certain diseases that thrive under wet, cool conditions, especially powdery mildew, which can be seen on plant leaves. Grapes are most susceptible, Perry said. It can be treated with sulfur or neem oil.

Perry warned against overwatering plants. With lower temperatures, plants don't need as much irrigation.

Bee staff writer Michelle Hatfield can be reached at or 578-2339.

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