Scientific Forecaster Discussion
fxus66 khnx 232339
Area forecast discussion
National Weather Service San Joaquin Valley - Hanford California
439 PM PDT Tue may 23 2017
Update...updated air quality issues.
temperatures begin to cool through the week, with this afternoon
and early evening the hottest period of the forecast. A few
showers and thunderstorms will remain possible over the highest
terrain the next few days. A building ridge allows for a warm up
at the end of the weekend.
today should be the last of triple digit heat, as Lemoore had
already crossed 100f earlier this afternoon. As the Rex block
across the Pacific breaks down, closed upper low pressure will
open and approach the coast, with jet Max rounding the southern
periphery of the former block perhaps delivering near Wind
Advisory criteria gusts across the coastal ridges and deserts
into Wednesday afternoon and Wednesday night. A cool down
continues through the week with the change in the pattern.
Elevated instability may just be sufficient enough to produce
some high elevation showers and thunderstorms late today and
tomorrow. 0.01" or greater probabilities from calibrated esrl
ensembles are a little farther south tomorrow and closer to 30
percent, so Wednesday afternoon features a slightly better chance
Flatter pattern into the weekend leads to more normal like
high temps, before deepening trough south of Alaska helps to pump
heights again along the West Coast, with temps warming. The
warmup and additional instability will lead to at least slight
chances for showers and thunderstorms across the High Sierra again
at the end of the forecast. Guidance has shown a small cool bias
with regards to heat in the longer term, so we may again be
experiencing triple digits to start the next work week. However
naefs height and temperature anomalies are forecast to be somewhat
less than what is being observed with our current event.
local IFR possible over the Sierra Nevada crest due to mountain
obscurations from isolated thunderstorms during this afternoon and
into early this evening. VFR conditions are otherwise expected
across the central California interior during the next 24 hours.
Air quality issues...
on Wednesday may 24 2017... unhealthy for sensitive groups in
Fresno... Kern... Kings... Madera and Tulare 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.
Certainty levels include low...medium...and high. Please visit
www.Weather.Gov/hnx/certainty.Php for additional information
an/or to provide feedback.