There may be a tiny bit of rain next week, but don't count on it coming anywhere close to solving the water supply questions that have hovered over the North Coast since spring.

For one thing, the parched earth is likely to soak up most of what falls as a storm system expected to hit Canada head-on skirts Sonoma and Mendocino counties, water officials say.

For another, the shifting forecast is less optimistic than it was even a few days ago, when it looked as if a whole inch of rainfall might be possible, meteorologists say.

The likelihood now is a fraction of an inch over a few hours late Monday or Tuesday, and maybe Wednesday, forecasters said.

"With my hay crops, the seed is just sitting in the ground waiting for the rain," said Sonoma County farmer Jim Groverman.

Groverman, who is well known for his pumpkin patch and corn maze off Highway 101 in Petaluma, also grows hay and silage. He said a weak rain storm, as expected next week, won't do much to get local grass growing.<NO1><NO>

"We need to get this grass started so we don<NO1><NO>'t get a big rain and get a lot of erosion," he said. "For the livestock guys, it's kind of tough. It would be nice to have the green grass by now."

The last measurable rainfall in Santa Rosa came on Sept. 30, when Santa Rosa received 0.08 inch of rain. Since the weather year began on July 1, the city has received a half-inch of rain, with most of that falling Sept. 23, according to Press Democrat records. In an average year, Santa Rosa normally receives 2.47 inches of rain in the same time frame.

The last significant rain in Sonoma County fell Dec. 23, when the area was drenched with 2.37 inches in one day.

The need to beef up storage in reservoirs is far greater than a single rainstorm can likely address, particularly with the fall chinook salmon run on the horizon raising the prospect of increased releases from Lake Mendocino, Sonoma County Water Agency personnel said.

A look at the reservoir north of Ukiah tells the story. The water level is alarmingly low, with just over 34,000 acre feet of stored water and vast patches of lake bottom around it, thanks in large part to an extremely dry spring.

The lake, the principal water source for communities and agricultural users from Healdsburg to Ukiah, is at its fourth-lowest level since 1959, and a sizable chunk of it is silt, agency personnel said.

Meanwhile, chinook salmon, though in small numbers yet, have begun migrating up the Russian River and are encountering shallow spots near Healdsburg that may need to be remedied, though water already is being released daily from Lake Mendocino at a rate of about 125 cubic feet per day, said Pam Jeane, assistant water agency general manager.

A larger number of the threatened fish are believed to be waiting off-shore, outside the mouth of the river in Jenner. With the breaching of the sandbar in the estuary Thursday and the potential for cooling temperatures and a bit of rain, they are expected to head upstream in greater numbers in the coming weeks, she said.

"At this point, it's not critical," Jeane said of the water supply. "We are planning on getting some rainfall.

"However, we have been very, very clear with the (wildlife) resource agencies about our concern about if we don't get any rainfall and what that means in terms of both" fish and humans, she said.

Jeane and agency spokesman Brad Sherwood said the situation would be far worse had consumers not answered the call to conserve over the summer months.

"We could be in pretty dire straits right now, and it made a very large difference for us," Jeane said. "And it gave us some flexibility this fall.

They urged residents to continue now, aided perhaps by the declining need for outdoor irrigation.

Sherwood also held out a possible incentive, saying residents who use less water in their homes over the winter also will reduce their sewer bills, which are based partly on water consumption.

"We're not out of the woods yet," he said.

(Staff Writer Martin Espinoza contributed to this report. You can reach Staff Writer Mary Callahan at 521-5249 or mary.callahan@pressdemocrat.com.)