May 2, 2016

This report covers conditions and observations made between Monday, April 4 and Sunday, May 1, 2016. The next scheduled report will be posted on Monday, June 6, 2016. In the event of any significant occurrences prior to that date, this site will be updated as soon as possible.

Our photos for the central region present an example of the Carmel variety near Modesto, followed by shots of the hail that fell in eastern Stanislaus County during the last week of the period.

While conditions during April were generally very supportive for the development of the 2016 crop, the period also brought a few days of adverse weather. Daily maximum temperatures varied widely, reaching into the mid and upper 80’s during the period’s opening week and again at mid-month. In between, readings ranged from the lower 60’s to mid and upper 70’s with coolest readings coinciding with the period’s wettest days. Morning low readings were a bit more stable, ranging predominately between the mid 40’s and mid 50’s.

Rain swept over the region on several days during the month, with the wettest periods recorded on the weekend on April 8-10. Though there were a few other brief, showery days, the month’s strongest storm built over the region on Wednesday, the 27th when thunderstorms brought strong winds, heavy rain and hail to areas of San Joaquin and eastern Stanislaus counties. Total rainfall accumulations for the period ranged from trace amounts to as much as 3.0 inches from the heaviest downpours. While there were some windy days during the period, with speeds reaching into the teens, the period’s strongest winds were recorded on the last weekend of the month, when gusts reached in excess of 35 mph.

The 2016 crop continues to develop in the central region, with only a few impacts from the adverse weather experienced during the final week of the month. Hail that fell in areas of San Joaquin County, from Manteca to Escalon caused few problems for growers in its path. However, heavy accumulations of larger hailstones that struck the area from Oakdale, south to Waterford and Hickman in eastern Stanislaus County did cause some nut loss and tree damage. Nuts damaged by the hail will continue to fall over the coming weeks.

Growers spent the period focused on irrigation and pest management. Deliveries of surface water have begun from local irrigation districts. While allocations of water from the federal Central Valley Project remain at 5% of contracted amounts, allocations from the State Water Project have been increased to 60%. Observers have reported that the irrigation season has begun in all areas of the region, though many growers have been able to delay irrigation as a result of the rain the region has received.

Growers in some areas of the region have reported increasing populations of Leaf-Footed Plant Bugs, which can cause severe damage to the crop through its feeding on the developing nuts. A few growers have reported that populations had built to the point requiring treatment. Growers are also watching populations of Peach Twig Borer, using pheromone traps to monitor the insect’s life cycle in order effectively time any control measures required.

Observers are reporting that the region’s orchards are growing heavy under the weight of the developing crop. Kernels have begun the solidification process, transitioning from a clear gel into a solid almond meat. Nuts that trees are unable to carry to maturity have nearly all been cast to the ground, a process that was aided by the blustery winds in the period’s final days.

By Mel Machado

Current weather at the National Weather Service
Jereme Fromm
KC Stone

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