Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Joaquin Valley - Hanford California
200 PM PDT Sat Aug 30 2014
clearing skies and slight cooling tonight as an upper-level
trough moves through the area. Temperatures rebound by Monday as
high pressure once again dominates the weather pattern.
satellite loops show a band of middle and high clouds moving through
central California. These clouds are associated with an upper-level
trough the Pacific northwest and northern California this afternoon.
The 12z models are in good agreement with the trough digging into
the Great Basin tonight...and the northern rockies Sunday.
Breezy conditions developed below the Tehachapi Pass this morning...
with gusts to around 45 miles per hour at Cache creek...as the trough moves
into the northern half of the state. At this time...the strongest
gusts were confined to the Cache Creek Area...but likely will expand
into the Mojave area this evening as the upper-level jet along the
back side of the trough aligns better with the Tehachapi Pass. The
winds are expected to diminish toward daybreak Sunday as the trough
moves east and the surface-pressure gradients begin to relax.
The upper-level ridge over the Desert Southwest/northern California
is forecast to build into California behind the trough. 500-mb
heights over central California will rise above 5880 meters Sunday
night...and remain high through Labor Day.
An upper-level trough is forecast to drop into the Pacific northwest
Tuesday. This will weaken the ridge and drop 500-mb heights over
central California below 5850 meters by 12z /0500 PDT/ Wednesday...
and below 5820 meters by 12z Thursday. The trough is forecast to
linger over northern California through the latter half of the week.
500-mb heights over California are forecast to rise slightly by the
end of the week as a closed low tries to form in the base of the
The initial trough will cool temperatures into the lower to middle 90s
Sunday. Temperatures will warm several degrees Labor Day as the
ridge builds into California. Temperatures will drop a few degrees
Wednesday as the next trough drops into northern California...then
little change Thursday and Friday with the trough nearly stationary.
Temperatures are forecast to warm slightly Saturday as the low
closes over northern California and 500-mb heights rise over the
central part of the state.
Then middle-level clouds might bring a few sprinkles to the higher
elevations of the southern Sierra Nevada tonight and Sunday
morning...but any significant quantitative precipitation forecast is unlikely. Beyond Sunday
morning...both the 12z GFS and European model (ecmwf) are dry for the next seven
Aviation... gusts up to 45 miles per hour below the passes and canyons of the
Kern County mountains through 12z Sunday. Otherwise...VFR conditions
will prevail across the central California interior during the next
Air quality issues...
The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is medium.
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 08-30 109:1988 80:1957 81:2007 49:1966
kfat 08-31 107:2007 69:1964 75:2007 50:1887
kfat 09-01 107:1888 73:1964 76:2007 51:1964
Kbfl 08-30 108:1988 80:1957 80:2007 45:1912
kbfl 08-31 111:1967 79:1966 80:2007 45:1912
kbfl 09-01 107:1902 74:1964 79:2007 53:1901