Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Joaquin Valley - Hanford California
224 PM PDT Tuesday Jul 7 2015
a weather disturbance will move across the region on Wednesday
night and Thursday...bringing the possibility of Westside and
Sierra showers and thunderstorms Wednesday evening and mainly in
the Sierra all day Thursday. Below normal temperatures and dry
conditions will stick around through the weekend with a gradual
warming trend early next week.
impressive vorticity maximum crossing the region at this time with best positive vorticity advection over
the east side of the Sierra and negative vorticity advection across our side. Have lowered
probability of precipitation significantly today across the Sierra.
WV imagery showing a closed low off the cencal coast at this time. The low
is projected to slowly move across cencal tomorrow afternoon and
Thursday before opening up and lifting NE late Thursday. Several
embedded vorticity maxes rotating around the main upper level low
center will play a key role for tstorm development tomorrow
afternoon and evening and again on Thursday. The h500 temperatures are
only around -14c which is not very impressive for strong to severe
storms and are not thinking that will be the case with the
system. Best instability is associated with the mountain areas.
Low level speed maximum coming around the base of the low center will
allow for increase surface pgrads and will produce locally strong
winds through the Pacheco and Cottonwood passes along the west
side of the valley. Guidance is going gusts to 50 miles per hour tomorrow
night as the low moves in. It will be short lived and will be very
Very good dynamics with the upper low will trigger convection on
Thursday across the Sierra with the GFS and NAM producing decent
quantitative precipitation forecast amounts as moisture will be wrung out as the low passes by.
Will monitor for burn scars flash flooding and expect wetting
rains across the Yosemite and Sequoia National Parks on Thursday.
With the cold core coming across we could even see snow above 11k
The low kicks NE as a baggy trough hangs off the coast and keeps
temperatures below or around normal with only a slight chance in the
Sierra through Saturday. Upper ridge is slow to retrograde Sunday
and Monday with warming trend and continued dry conditions.
local MVFR ceilings in isolated showers and thunderstorms over the
southern Sierra Nevada until 06z Wednesday and again after 19z on
Wednesday. Windy conditions possible along the coastal range after
16z Wednesday. Otherwise...VFR conditions will prevail throughout
the central California interior during the next 24 hours.
Air quality issues...
The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is high.
This information is provided as part of a trial project conducted
by the National Weather Service San Joaquin Valley - Hanford.
Certainty levels include low...medium...and high. Please visit
www.Weather.Gov/hnx/certainty.Php /all lower case/ for additional
information and/or to provide feedback.
site date hi_max:year lo_max:year hi_min:year lo_min:year
Kfat 07-07 111:1905 84:1891 76:2014 53:1903
kfat 07-08 115:1905 84:1983 81:1896 51:1891
kfat 07-09 113:1905 78:1936 81:2008 55:1983
Kbfl 07-07 114:1905 85:1983 81:1968 46:1903
kbfl 07-08 114:1905 85:1983 79:1907 50:1899
kbfl 07-09 113:1905 83:1980 84:2008 52:1923