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fxus66 ksto 192311 
afdsto

Area forecast discussion
National Weather Service Sacramento California
411 PM PDT Thu Oct 19 2017



Synopsis...
rain chances along with High Mountain snow and gusty winds this
evening and Friday. This will be followed by a warming trend early
next week with above normal temperatures through the week.

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Discussion...
strong frontal band with quick burst of precip will shift east
over norcal late this afternoon and evening. Snow levels will
start off high above 8000 feet..but drop rapidly after midnight
falling to below 6000 feet. This will cause a quick transition
from rain to snow over the Sierra which is likely to cause a
period of hazardous travel along Interstate 80 and Highway
50...especially after 2 am. From 3 to 6 inches of snow possibly
locally higher amounts will accumulate by Friday morning. Rainfall
amounts up to 1.50 will be possible over the mountains...0.25 to
0.50 over the valleys. This will be the first widespread rain
event over many of the fresh fire burn scars...ash and floatable
debris may clog drains and small streams. Residents near burn
scars should monitor flood prone areas for any water rises. Wind
gusts to 30 mph will be possible over the northern and central
Sacramento Valley this evening.

Trough will shift east Friday and Saturday, lingering moisture
will will keep a few showers over the mountains through Saturday
morning. High temperatures in the 60's Friday will warm back into
the 70's Sunday...as high pressure re-builds over norcal.

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Extended discussion (monday through thursday)
high pressure continues to dominate over California through the
extended period. Warm and dry conditions will persist across the
forecast area with temperatures ranging 10-15 degrees above normal
through Thursday. Valley daytime temperatures will remain in the
mid to high 80s and the foothills and mountains will range from
the 70s to 80s. Could see gusty winds Monday in the western
Sacramento Valley as the ridge axis increases over the West Coast.
Hec &&

Aviation...
VFR conditions at taf locations. Valley and ridge winds beginning
to increase this afternoon, especially over the ridgetops and
North Sacramento valley. Gusts at taf sites could range between
15-25 kts, then decrease after 08z. Precipitation will move into
interior norcal around 00z and impact taf sites through Friday
morning with MVFR ceilings possible at times. Jbb/hec



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Sto watches/warnings/advisories...
Winter Weather Advisory from 11 PM this evening to 11 am PDT
Friday for West Slope northern Sierra Nevada-western Plumas

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