Temperatures in Pleasanton today are forecast to reach a high of 67 degrees by mid-day, tying the record set in 1958. That would be a welcome high compared to the record low of only 21 degrees set for this date in 1961.

The National Weather Service predicts this could also be the last day of near-record highs of the winter months as the thermometer dips into the low to mid-60s for the rest of the week.

The good news of more warm temperatures is clouded by a report yesterday that California's mountain snowpack was among the driest on record for Jan. 3, the California Department of Water Resources said.

The mountain snow that melts into reservoirs, streams and aquifers in the spring and summer provide approximately one-third of the water for the state's households, farms and industries.

"Fortunately, we have most of winter ahead of us, and our reservoir storage is good," Department of Water Resources Director Mark Cowin said.

State water managers said they are cautiously optimistic about this year's water supply.

Manual and electronic readings today determined the snowpack's statewide water content is 19% of the Jan. 3 average and only 7% of the average April 1 measurement when the snowpack is normally at its peak before the spring melt.

Readings were taken this morning at four locations at elevations between 6,500 and 7,600 feet near Echo Summit in the Sierra.

The snow depth was zero at the 7,600-foot Alpha station and 7.1 inches at 6,700-foot Lyons Creek.

Electronic readings indicate the water content in the northern mountains is 21% of normal for Jan. 3 and 8% of the April 1 seasonal average, according to the DWR.

Water content in the central Sierra is 13 percent of normal for today's date and 5% of the April 1 average.

The southern Sierra numbers are 26% of average for Jan. 3 and 9% of the April 1 average.

On Wednesday, the Department of Water Resources said the snowpack water content statewide at the end of an unusually dry December is only 24% of normal for that date. On Dec. 27, 2010, the statewide snowpack water content was 202% of average.

"Thanks to good reservoir storage left over from last winter's storms, we anticipate an adequate water supply next summer," Cowin said.

"Our initial estimate is that we'll be able to deliver 60% of the slightly more than 4 million acre-feet of water requested from the State Water Project, and we hope to increase the percentage as winter storms develop," Cowin said last week.

An acre-foot is 325,851 gallons, enough to cover one acre to a depth of one foot.

The snowpack surveys are conducted on the first of the month from January to May.

The manual surveys supplement and check the accuracy of real-time electronic readings from sensors in the state.