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Area forecast discussion 
National Weather Service Medford or
300 am PDT Sat may 30 2015

Discussion...a similar pattern sets up today compared with
yesterday...but with increased instability...broad but weak to
moderate upper level divergence and a weak short wave cycling
through the area around maximum heating there should be increased
thunderstorm activity this afternoon into the evening. Even though
an increase is convective activity is expected...the thunderstorm
coverage that does develop is expected to still be isolated. On
Sunday the cold front approaches the region with greatly increased
southerly flow feeding warm moist air into the area. This will
combined with increased upper divergence and very strong low level
Theta-E convergance as several short waves cycle through...this
should bring a chance of scattered thunderstorms from the coastal
range to a little east of the Cascades into the late evening. With
the increasing jet contribution and lingering elevated instability
thunderstorms could linger into overnight...especially in the
northern Cascades before the cold front brings much cooler and
stable air in Monday.


Aviation...for the 30/06z taf cycle...expect MVFR/IFR ceilings along
the coast in the marine layer the rest of tonight through much of
Saturday. MVFR ceilings to should develop in the Umpqua basin around
krbg about 12z, but are likely to erode by 17z or 18z. The rest of
the area will be VFR tonight through Saturday, though isolated
thunderstorms will develop from the higher terrain of Southeast
Jackson County to Klamath and Northern Lake counties. -Bpn


Marine...updated 800 PM PDT, Friday, 29 may 2015...seas of 4-5 feet
with gentle to moderate northerly breezes will persist over most of
the waters through Saturday night. Weak low pressure will move into
the waters Sunday and Monday with some showers. Winds will shift
into the south for a while Monday, then shift to southwesterly as
the low moves northward and onshore. Even so, they should remain
light enough for seas to remain low. A thermal trough is expected to
redevelop as early as Wednesday and is likely to bring moderate to
strong north breezes and wind driven seas back to the area Thursday
and Friday. Spilde


Mfr watches/warnings/advisories...


Pacific coastal waters...none.



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