Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Medford or
214 am PDT Thursday Apr 2 2015
Discussion...there are still some low topped showers over the
coast and waters as well as some light upslope showers in the
mountains, but all of this is occurring under the radar (no pun
intended). While things will be much more stable today, we expect
to see isolated showers roaming these areas through this
afternoon, so low probability of precipitation remain. The temperature forecast has been
working out quite well, and the freeze warning for the Shasta
Valley appears to be on track again this morning. Winds have
lasted further into the night, so it may not be quite as cold
there as last night, but still below freezing over much of the
area. Winds will be weaker there tonight and Friday morning, so
one more night of freezing weather is expected tonight. West side
Oregon valleys have remained above frost/freeze thresholds as
expected, so no changes there.
Any remaining showers will dry up this evening, and then dry
weather is expected through Friday for most areas. The exception
will be along the coast where a front will bring rain later
Friday. This front does not look all that strong with rain mostly
confined north of the Umpqua Divide Friday night, but it will be
followed by cool air and lowering snow levels. While Saturday will
mostly be dry, a broad upper low will arrive Sunday bringing
valley rain and mountain snow off and on into the middle of next
week. As the previous shift noted, timing of the various features
within the low will be a challenge, but the models still hint at
a particularly wet system moving through the long wave trough in
the Monday time frame. While the details even with this system
vary between models, it is one to keep an eye on as it could
produce large amounts of snow in the mountains. Probability of precipitation have been
raised for much of the period between Sunday and Tuesday using a
blend of models. -Wright
Aviation...for the 02/06z taf cycle...from the Cascades
west...areas of MVFR ceilings will develop over the west side valleys
tonight with higher terrain obscured...clearing to VFR by late
Thursday morning and remaining VFR through Thursday evening. East
of the Cascades...VFR conditions will persist through Thursday
Marine...updated 900 PM PDT Wednesday 01 Apr 2015...offshore high
pressure will build into Thursday...then weaken Thursday night.
This will bring north winds to the area...but they will likely
remain below advisory criteria. A cold front will move onshore
Friday afternoon. Low pressure will then set up offshore...
bringing unsettled showery weather to the area through the
weekend. Winds will be mostly light except for gusty conditions
near showers. Another front will move onshore Monday...bringing
another round of moderate south winds and choppy seas to the
California...freeze warning until 9 am PDT this morning for caz081-281.
Freeze warning from 1 am to 9 am PDT Friday for caz081-281.
Pacific coastal waters...Small Craft Advisory for hazardous seas until 5 am PDT early
this morning for pzz356-376.
Small Craft Advisory for winds until 2 am PDT early this morning
Small Craft Advisory for winds from 2 PM this afternoon to 11 PM
PDT this evening for pzz376.
Small Craft Advisory for hazardous seas from 2 PM this afternoon
to 11 PM PDT this evening for pzz376.