July 4, 2020 – Dry weather with seasonable temperatures for the next week.
Discussion
Skies are clear across interior NorCal early this morning. Ft Ord
profiler shows a suppressed marine layer early this morning and
weaker Delta winds. Current temperatures are running 2 to 6
degrees warmer compared to readings observed early Friday.
Heights aloft will rise this holiday weekend as the PacNW trough
weakens and the southwest high nudges northward. This will lead to
a slight warming trend. Today’s highs will be within a degree or
two of normal north of I-80, and then up to 5 degrees above normal
along and south of I-80, except about 8 degrees above normal at
Delta locations due to the weaker marine influence. Mid 80s to
upper 90s are expected in the Valley and foothills. On Sunday,
models indicate a slight increase in Delta flow, but temperatures
will remain similar to today’s.
By early next week, ensembles depict the upper trough slowly
sagging southward into the region. Thus, the marine layer will
likely deepen with increased onshore flow and slightly below
normal highs. Forecast highs in the Valley will be in the low to
mid 90s, with upper 60s to low 80s over the mountains.
Extended Discussion (Wednesday through Saturday)
Ensemble means continue strong ridging over the central CONUS
while maintaining a weak trough along the West Coast later next
week. Dry weather with temperatures close to average is expected
to persist.