Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Medford or
310 am PDT Tuesday Mar 11 2014
Discussion...an upper ridge will build in over the Pacific
northwest over the next couple of days, then begin to flatten out
middle week, and finally be replaced by zonal upper flow toward the
end of the week. This will result in dry weather through the week.
Given this pattern, little was changed in the forecast this
morning. The primary focus was on improving the temperature and
Speaking of wind, offshore flow will increase as the ridge builds
today and tonight and then peak as the ridge peaks in intensity
Tuesday. The models are forecasting at least breezy winds in most
locales by later this afternoon and this evening, and this
includes portions of the Rogue Valley. We're not expecting enough
wind for advisories over most of the area, but with both the
Medford/Klamath Falls and Medford/Redding gradients approaching 7
mbs late this afternoon and evening, stronger winds are possible
through the southern end of the Rogue Valley around Ashland. I
hoisted a Wind Advisory for this afternoon through tonight for
the Ashland area.
Gradients decrease during the day Tuesday and this allows winds to
ease over the valleys, but they will continue to blow through the
mountains until the ridge axis finally moves inland Tuesday night.
It looks like we're in for a stretch of dry and mild weather with
the next chance of rain coming Friday, and even that is likely to
be north of US. The next real threat of widespread rain probably
won't come until next week. -Wright
Aviation...based on the 11/06z taf cycle...
VFR will prevail across much of the area overnight into Tuesday. Due
to recent rainfall, expect areas of IFR fog/low clouds to develop in
some of the west side valleys early Tuesday morning lasting through
about 17-18z. This is most likely at krbg, but could also occur in
the rogue and Illinois valleys. Brief IFR may also occur along the
coast, but shouldn't last more than a couple of hours. A strong
pressure gradient developing across the area Tuesday will cause
gusty east/southeast winds over the terrain, the east side and
valleys that are prone to such winds. Gustiest winds will likely be
during the afternoon at klmt, where gusts to 30kt are possible.
Marine...a thermal trough developing along the Oregon coast will
bring increasing north winds and are expected to be strongest beyond
5 nm from shore in the area from Cape Blanco southward. Could not
rule out a few gust near 35 kts this afternoon and evening, but
should remain below that mark most hours. Steep wind driven seas are
also expected due to moderate north winds. Gusty north to northeast
winds will peak at Small Craft Advisory levels of 25 to 30 knots this
afternoon and evening then taper off tonight into Wednesday morning.
Small Craft Advisory level seas are expected across the area.
However for areas beyond 10 nm from shore from Port Orford south,
seas are expected to become very steep and build to hazardous seas
Then the next frontal system will remain well north of the waters
but it will generate a rapidly increasing long period west to
northwest swell Wednesday night through Wednesday night. Seas
will diminish Thursday into Friday. Then another frontal system
will remain north of the waters and produce an increasing west to
northwest swell Saturday into Sunday. -Petrucelli
or...Wind Advisory from 11 am this morning to 5 am PDT Wednesday for
Pacific coastal waters...Small Craft Advisory for winds from 5 PM
this afternoon to 5 am PDT Wednesday for pzz350-356-370.
Small Craft Advisory for hazardous seas from 2 PM this afternoon
to 5 am PDT Wednesday for pzz350-356-370.
Small Craft Advisory for winds from 8 am this morning to 5 am
PDT Wednesday for pzz376.
Hazardous seas warning from 2 PM this afternoon to 11 PM PDT
this evening for pzz376.
Small Craft Advisory for hazardous seas from 8 am this morning
to 5 am PDT Wednesday for pzz376.