30-Day Weather Outlook for March 27, 2017, to April 27, 2017
Summary- We have a brief break in the wet pattern for a few days. The tendency for troughing near and west of N California continues, even as we approach the normal end of the season. Forcing for troughs occurring from the N and north-central coast and WSW-ward is from the sea surface temperature anomaly (SSTA) pattern W of north-central Calif. Forcing for troughs over SE Calif, NW Mexico and Arizona and S Great Basin may still be related to the currently weak El Niño, although the seasonal factors that affect El Niño’s influence are decreasing with the approach of summer.
In the Near Term – March 30 - April 13… The NOAA/CPC outlook for April 4-10th shows a turn to mild but wetter normal conditions in coastal Calif, but continued showery conditions or frequent rain events for the Sierras.
In the southern California avocado growing areas from Santa Barbara County to San Diego County, most of the rain activity remains north of SOCAL. A little light rain or drizzle occurs in coast and valley areas on March 30th and April 5-11th. A few light showers occur in the Tehachapi Mountains on March 30th and again April 5-11th.
Summary – April 14-28… In the southern California avocado growing areas, from San Luis Obispo south, the southern branch of westerlies may redevelop in late Apr, and induce development of cutoff lows or fronts. There are showery episodes which appear minor. In late Apr there will be below normal temperatures for southcentral Calif, and some of this could also affect S Calif.
Seasonal Outlook / El Niño Update...April 29 – June 1, 2017… Troughing is still possible to some extent, with some drizzly mornings during May. El Niño influence is minimal, but sea surface temperature anomaly pattern in the east Pacific off northern California continues to support troughing near the coast. Currently, we look for a better than average chance for some late season showers in N and central Calif and drizzle/light rains into San Diego County during at least the first half of May.
Current guidance for temperatures supports warmer than normal conditions in N Calif for most of May. Eventually we develop warmer than normal conditions through SOCAL, but probably not occurring until the last 10-12 days of May.
...Alan Fox, Fox Weather LLC...