Weather Report as of mid-June
- Latest weather report as provided to the SC avocado growers (but it works for us ordinary folks too...
Weather: 30-Day Outlook For California's Coastal & Valley Areas
Synopsis...A warm sea surface temperature anomaly exists along 35 - 47N in the Pacific from the 165W to 135W, but the sea surface is still a little colder than normal near the southern California coast and southwestward between Baja California and Hawaii.
On the 7th and 8th we had the expected spike of hot temperatures (107-113 degrees) in the interior sections of central and northern California. This hot and dry event was followed by thunderstorms with dry lightning. High evapotranspiration was observed during the hot days in northwest California valleys.
In the Near-Term - Southern California Avocado Region, June 12-25...
The current weather pattern indicates troughing and cool, coastal eddy conditions. The coolest period will be from the 15th to the 19th. During the 20th to 25th, a warm-up is expected as we return to a more seasonable and dry summer pattern.
June 26 to July 11...Southern California Avocado Region...
Normal marine layer conditions are expected. At issue this season would be the occasional periods of shallow marine layer and hot conditions in the foothills and coastal hills.
Monsoonal thunderstorms are not expected to develop until a well developed deep flow begins from the southern Gulf of California into southeastern California and Arizona. Such conditions are not expected to develop until after about July 11.
Seasonal Outlook/El Niño Update... (July 12 - September 30)
We are currently seeing a weak, cold La Niña condition (colder than normal sea surface) off the coast of Peru. +About mid-summer (late July), weak El Niño conditions are expected to begin, and this is expected to lead to an increase in El Niño conditions through fall and winter months and into the spring months of 2014.
We will begin the transition to El Niño and warmer than normal sea surface temperatures off to the southwest and southern coast of Mexico in late August and September.
This will tend to shift the focus of tropical cyclone activity to the Pacific side of Mexico with a possible later season bloom of tropical cyclones off the south coast of Mexico and southern Baja California.
Such conditions will transport moisture north along the western portions of Mexico and Baja. Eventually we should see some increase in moisture with thunderstorms into California and Arizona as the monsoonal pattern increases in the mid and late summer months.
Southern California Avocado Region...(July 12 - September 30)
We will transition to monsoonal southeastern flow conditions in the middle of July accompanied by thunderstorms in the mountains and deserts as is normal.
In Mexico, there will be support for some tropical cyclones in early July near the south coast of Mexico. As the season develops, we should see a more typical active period of tropical cyclones off the south coast of Mexico.
This will cause moisture to recurve north along western Mexico into southern California and Arizona to produce thunderstorms. In southern California, such storms may affect the avocado regions in late July, August, and in September.
As El Niño develops, more cutoff lows will be possible in September off Baja and southern California causing more frequent thunderstorm activity over southern California.
also online at http://www.californiaavocado.com/latest-greensheet-edition