Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 291530
Area Forecast Discussion
National Weather Service Sacramento CA
830 AM PDT SUN MAY 29 2016
Very warm weather expected this week as high pressure strengthens.
A few afternoon showers or thunderstorms possible along the Sierra
Mainly clear skies across interior NorCal this morning.
Temperatures will inch up a few more degrees today as high
pressure strengthens a bit. Still enough moisture and instability
for another round of afternoon and early evening showers and
thunderstorms over the Sierra to the south of Tahoe. No updates.
Another warm day in store for interior NorCal today as high
pressure ridging over the Eastern Pacific begins building into the
West Coast. Highs today: valley in the low 90s, delta in the mid
70s to mid 80s, foothills in the 80s, mountain highs in the 60s
and 70s. There`s another chance for Sierra convection this
afternoon due to low pressure lingering over SoCal. However, any
showers or thunderstorms that develop will likely be limited to
the higher elevations of the Sierra south of Tahoe.
Memorial Day and Tuesday will kick off the week with hot
afternoons. High pressure will strengthen over NorCal on Monday
and Tuesday causing the peak of this current warming trend.
Valley highs will be in the mid to upper 90s. A few locations may
even top out around 100 degrees on Tuesday when daytime highs
measure 10 to 15 degrees above normal.
By Wednesday, the high pressure will begin to shift eastward and
weaken. This will finally allow temperatures to gradually cool,
but only by a few degrees. Residents should still be prepared for
a hot day with valley highs in the mid to upper 90s with 70s and
80s across higher terrain. Keep in mind to stay well hydrated for
the first half of this week as many of us are not used to the hot
.EXTENDED DISCUSSION (THURSDAY THRU SUNDAY)...
Models continue to show strong high pressure over the western
U.S. bringing above normal temperatures through the extended
period. Daytime highs will climb slowly to more than 15 degrees
above normal by Saturday. Models fairly consistent in positioning
an upper low off the Socal coast Thursday and Friday. This will
result in southeast flow aloft and GFS, ECMWF and GEM models all
painting some convective precipitation over the northern Sierra
each afternoon. Therefore...have included a slight threat of
afternoon and evening thunderstorms in this region Thursday
through Saturday. Models diverge by next Sunday in both dealing
with the Closed low off the Socal coast and a Pacific frontal
system possibly approaching the Pacific Northwest coast. Depending
on the upper lows position...northern Sierra could see another day
of showers next Sunday. The second feature of approaching frontal
system now not looking as likely with 06z run of GFS already
backing off on this idea. Either way, should see a little cooling
most areas early next week.
VFR conditions next 24 hours TAF sites. Isolated thunderstorms
possible afternoon and evening hours over the northern Sierra
crest. Sustained winds generally below 15 knots.