Area Forecast Discussion
Issued by NWS Medford, OR
FXUS66 KMFR 261552
Area Forecast Discussion
National Weather Service Medford OR
852 AM PDT Wed Apr 26 2017
.UPDATE...Showers continue this morning across the area, but will
taper through the rest of the day. Web cams show snow levels of
around 5000 feet, which is right in line with the forecast, and
the Winter Weather Advisory continues for the Cascades north of
Crater Lake. Winds should pick up on the East Side today as well,
and wind advisory is in effect there through this evening. Once
this system passes, expect clear and warmer conditions through the
For more information, see the previous discussion below. -BPN
.AVIATION...26/12Z TAF CYCLE...A cold front will move through the
area this morning. Widespread IFR ceilings and visibilities will
impact coastal areas this morning with moderate rain and local LIFR.
Conditions there will begin to improve after the cold frontal
passage around 15Z, but a mix IFR and MVFR with lighter showers is
still expected through Wednesday afternoon. The coastal mountains
will remain obscured through late afternoon.
Inland, conditions will remain mostly MVFR with occasional rain and
higher terrain obscured into early afternoon. Local IFR is possible
with the frontal passage this morning. Precipitation will become
more showery in the afternoon into the early evening with a mix of
MVFR and VFR. Gusty west to northwest winds will develop east of the
Cascades this afternoon. Wind gusts to 30 kt are expected at KLMT,
which will likely lead to some bumpiness on takeoffs and approaches.
.MARINE...South winds will continue this evening as a quick
moving storm system passes over the region. Southerly winds will
persist into early Wednesday morning then winds will quickly turn to
the west, then to the north during the day Wednesday. The area will
then be under the influence of high pressure beginning Thursday and
Friday. This will tighten the pressure gradient offshore and result
in northerly small craft winds and a fresh short period swell.
Northerly winds are expected to continue into early next week.
Additionally, a westerly swell in the 10 to 12 second range will
persist through much of the forecast period. /CC
.PREV DISCUSSION... /Issued 331 AM PDT Wed Apr 26 2017/
DISCUSSION...Rain is spreading inland early this morning.
Precipitation at the coast range from around half an inch in Coos
County and around an inch in southern Curry County. Snow levels so
far are around 6000 feet and not quite as high as we had
anticipated. The occluded front will move inland early this
morning and will keep the snow levels around 5500-6000 feet. While
this is higher than the Siskiyou Pass, snow could accumulate on
Hwy 140 pass across the Cascades, and a winter weather advisory
was issued through 5 pm this afternoon for Oregon Zone 27 which is
the Cascades down to Crater Lake. Snow is expected across the
southern end of the Cascades as well but amounts are expected to
be less. Travels across Highway 66 and Dead Indian Memorial
Highway could also be impacted.
The front will also bring gusty west to southwest winds to areas
east of the Cascades from late morning today. H7 winds are
forecast to increase to 43 knots and a wind advisory has been
issued and will continue today. Of concern are winds at Kingsley
Field which could gust up to the mid 30s Early this afternoon.
Precipitation is expected to turn to showers late this afternoon
but NW flow aloft will keep upslope snow showers going in the
mountains. Additional inch is expected at Crater Lake and in the
Cascades down to around the California state line. Little to no
addition precipitation is expected in Siskiyou and Modoc Counties.
On Thursday a ridge will start to build into the eastern Pacific.
NW flow aloft is expected to weaken with precipitation confined
mainly to Coos and Douglas Counties, and in the Cascades down to
around Crater Lake. The upper level ridge will build into our area
Friday and Saturday. High temperatures are expected to return to
seasonal norms on Friday (which is around 65 for Medford) then
rise to around 70 next weekend. During this time the thermal
trough is expected to build northward to the coastal area with a
drying trend at the upper slopes and ridges.
The latest GFS/ECMWF show a weak front moving across WA and
northern OR Sunday. This will weaken the ridge slightly with
possible showers north of the Umpqua Divide. This scenario would
lead to slight cooling on Monday, down to near seasonal norms.
However we could be in for a period of drastic warming from next
Tuesday as both the GFS/ECMWF are now advertising a large area of
ridging from the eastern Pacific into the West Coast. Highs in the
upper 70s are not unreasonable for Medford around the middle of
next week. /FB
OR...Wind Advisory until 8 PM PDT this evening for ORZ030-031.
Winter Weather Advisory until 5 PM PDT this afternoon ABOVE 5500
FEET for for ORZ027.
CA...Wind Advisory until 8 PM PDT this evening for CAZ085.
Pacific Coastal Waters...None.