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FXUS66 KSTO 191015

Area Forecast Discussion
National Weather Service Sacramento CA
315 AM PDT Mon Aug 19 2019

Temperatures close to average early this week will return to above
average for the second half of the week. Dry weather pattern


Clear skies cover the region early this morning other than some
stratus nosing into the west Delta from the Carquinez Strait.
Current temperatures range from the mid to upper 40s in the colder
mountain valleys to the upper 50s and 60s across the Central

Very weak trough lingers across the region early this week
maintaining temperatures close to average for mid-August with
light to moderate onshore flow. Short-wave forecast to brush by to
the north on Wednesday, then high pressure will strengthen and
northerly flow develop in its wake leading to a return of above
average temperatures across the region.


To conclude the work week, mid-level heights will rebound after 
the passage of a longwave trough to the north. Gradual height 
rises are to continue into the weekend as an expansive upper ridge
takes shape over the southwestern U.S. The amount of warming this
pattern shift provides is unknown given differences in the global
ensembles. Most notably, the 00Z ECMWF ensemble mean has 
maintained the more stout ridge with 500-mb heights approaching 
the upper 590 dm range. Meanwhile, the 06Z/00Z GEFS ensembles 
deamplify the mid-latitude flow supporting less impressive daily 
temperatures. At this point, it is safe to say temperatures will 
remain above average from Friday through the weekend and into the 
start of next week. Current forecast highs support readings near, 
to slightly above the 100 degree mark in the Valleys while 80s can
be found in the mountains. These numbers equate to roughly 5 to 
10 degrees above climatology. Given some of the more robust ECMWF 
solutions, there may be room to raise these numbers. ~BRO


VFR conditions expected the next 24 hours. Some brief lower 
ceilings possible from marine stratus through 17Z, generally 
Sacramento westward. Gusty winds up to 30 knots possible across 
the Delta and its vicinity. Otherwise, typical diurnal wind 
patterns for summertime in NorCal are anticipated. ~BRO



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