Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Sacramento California
917 am PDT Sat Aug 1 2015
a cooling trend continues into Sunday. Daytime highs near normal
today and at or below normal much of next week. Scattered
mountain thunderstorms through Monday as monsoon moisture is
pulled northward...elsewhere continued dry.
some isolated thunderstorms popped up over west end of the valley
and moved over Southern Lake County. That activity continues to
move northward elsewhere showers are popping up over the
mountains with the most heavily concentrated area located over the
Burney Basin. Thunderstorms should be developing over the Sierra
range by 11 am this morning. Today and tonight should be the most
active time for thunderstorms. After Sunday most of the activity
look to push to east of the crest. There is still some uncertainty
for Tuesday but a weak shortwave may trigger some activity mainly
over the northern half of the forecast area.
Strong Delta breeze is helping to keep inland temperatures a
little bit cooler today. Moderate to strong Delta breeze is
expected to continue the next several days.
Extended discussion (wednesday through saturday)
Weak trough forecast along the West Coast during the extended
period while the strong upper ridge is centered well to our east
over the Great Plains. Westerly flow aloft is likely to keep
thunderstorm chances east of the Sierra crest through much of the
period, however, a weak closed low in the base of the trough is
forecast to approach the region late in the week and may bring an
increased chance for deep convection over the higher terrain.
Temperatures will be close to average for early August.
VFR conds next 24 hours exc scattered MVFR conds vicinity thunderstorms and rain over mountains. Southwesterly
winds 25-35 kts carq Strait and West Delta through 12z sun. Elsw, winds
generally less than 10 kts exc becmg southerly 10-20 kts in the SAC valley