Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Joaquin Valley - Hanford California
352 PM PST Sat Dec 27 2014
Update...air quality issues updated.
continued mostly clear skies as weak high pressure dominates. Some
patchy late night through early morning fog possible on Sunday as
well as some areas of frost.
Discussion...upper level northwesterly flow over the region
brought mostly clear skies and near normal temperatures to the
region this afternoon. Temperatures in the valley reached the middle
50s...while the desert locations warmed into the upper 40s.
Temperatures are forecast to warm a few degrees by the evening
Little change in the weather pattern overnight...with patchy frost
possible once again through many of the valley and foothill
locations. Forecast confidence is only medium with regards to
overnight low temperatures...as middle level clouds may impact part
of the region. If clouds do move over the area...the overnight
lows will likely be warmer than forecast and prevent frost
Northwest flow will continue to dominate the weather pattern
through early Tuesday morning...before an upper trough drops
southwest toward central California from the Great Basin. The
upper trough is forecast to become a closed low on Tuesday
afternoon over southern Nevada and central California. The closed low
will then move south into Southern California into Wednesday
before ejecting east Thursday into Friday.
This closed low will have a few impacts to the region. The first
will be the possibility of rain and low elevation snow. Cold air
will filter into the region behind the upper low dropping snow
levels significantly from Tuesday into Wednesday. Precipitation
is forecast to move into Mariposa and Tuolumne counties along the
Sierra Nevada with snow levels around 3500 feet early Tuesday
morning. The chance for precipitation will shift south on
Tuesday...with a least a slight chance of rain/snow for much of
the area Tuesday afternoon into Wednesday morning. By Wednesday
afternoon all chances for rain/snow will be confined to Tulare and
Kern County. Snow levels will fall to between 2000 and 2500 feet
Tuesday night into Wednesday...with light snow accumulation
possible. This low is relatively moisture starved...so if it does
rain or snow...only light accumulation is possible.
Forecast confidence is only medium at this time with the middle week
upper low. Ncep's ensemble mean forecast is indicating only medium
predictability. Additionally...the naefs probability of
precipitation is indicating very low chances of measureable
One thing we are confident about are the cold temperatures.
Daytime high temperatures through the valley will be around 5
degrees below normal...with readings in the upper 40s to low 50s.
Overnight low temperatures will also near the freezing mark...and
possibly even colder as we near the event.
Please continue to monitor the forecast for the latest
Otherwise...upper level northwest flow returns to the area Friday
into the weekend with near normal temperatures and dry weather.
in the San Joaquin Valley...local MVFR visibilities in mist from 06z
through 18z sun. Otherwise...VFR conditions can be expected throughout
the central California interior during the next 24 hours.
Air quality issues...
on Sunday December 28 2014... fireplace/wood stove burning
status is: no burning unless registered in Fresno... Kern...
Kings and Madera counties.
Further information is available at valleyair.Org
The level of certainty for days 1 and 2 is medium.
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 12-27 72:1991 37:1908 55:1977 23:1962
kfat 12-28 66:1945 35:1908 54:1977 24:1962
kfat 12-29 69:1949 36:1908 54:1977 24:1990
Kbfl 12-27 72:1991 39:1933 56:1977 23:1930
kbfl 12-28 73:1977 40:1908 58:1977 24:1930
kbfl 12-29 73:1956 40:1929 57:1977 22:1929