Calapooya Trail, Oregon Weather Forecast Discussion

128
FXUS66 KMFR 012136
AFDMFR
Area Forecast Discussion
National Weather Service Medford OR
236 PM PDT Wed Oct 1 2025
.DISCUSSION (Today through Tuesday)...
Overview:
Rounds of isolated showers are expected through today, tomorrow, and
to a lesser extent on Friday. These chances are closely tied to an
upper level system that will essentially park around Vancouver
Island through this stretch providing upper level support.
Temperatures will generally be cooler through this stretch compared
to normal values, and we may need to consider frost/freeze products
for the eastside later this week. Sunday into early next week we
will see temperatures trend upwards near normal, but still expecting
cold nights on the eastside. A dry stretch looks to start Friday and
continue through at least early next week.
Further Details:
Water vapor imagery depicts a strong closed low off shore from
Vancouver Island. The placement of the low is ejecting PVA over the
forecast area, and the combination of moisture advection and
lift/energy aloft will produce isolated showers across the area as
this low remains parked in this generally vicinity for the next
couple of days. This will produce light rainfall under isolated
showers these next two days. Not expecting much--if any--lightning
but we could see very isolated strikes Thursday afternoon. By
Friday, this low will start to push onshore and start to develop
into a long wave trough consuming much of the CONUS by Sunday.
Showers activity is expected to lessen much on Friday with chances
confined to east/southeastern portions of the forecast area as
dynamics shift eastward. In fact, wouldn`t be surprised if these
PoPs on Friday get lowered or were removed completely from the NBM
on future runs.
Barring any changes, conditions are expected to turn dry Friday with
precipitation chances ending. These conditions will likely continue
into early to middle of next week. The one caveat is Monday when a
low slides down from Canada. Models vary on the placement of this
low which will have some impact across the region as to where
precipitation will end up being. For example, there are stark
differences between the GFS and European models on the placement and
evolution of this low. That said, nearly all ensemble members are
indicating dry conditions, so confidence is high we will remain dry
this weekend and early next week.
-Guerrero
&&
.AVIATION (18Z TAFs)...
A combination of showers, fluctuating ceilings, and breezy
conditions will be evident through this cycle. Ceilings and whether
showers impact terminals or not will be the most uncertain given the
isolated nature of showers today. That said, a combination of IFR
and MVFR conditions may develop this cycle as an upper level low
remains in place near Vancouver Island.
-Guerrero
&&
.MARINE...Updated 200 PM PDT Wednesday, October 1, 2025...The
main change was to shorten the current Small Craft Advisory to
expire during Thursday evening rather than early Friday morning.
Currently, south winds are diminishing, but high and steep swell
dominated seas will remain near a 12 to 15 ft  at 13 seconds peak
through tonight. Seas then gradually diminish beginning Thursday,
but remain steep through Thursday evening. Seas continue to diminish
but the dominant wave period also decreases Friday into early
Saturday.
With the development of a thermal trough, north winds near or above
advisory strength and steep seas are likely Saturday  into Sunday
night. -DW
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...CA...None.
PACIFIC COASTAL WATERS...Small Craft Advisory until 9 PM PDT Thursday
     for PZZ350-356-370-376.
&&
$$

NWS MFR Office Area Forecast Discussion