Area Forecast Discussion
Issued by NWS Medford, OR
FXUS66 KMFR 281023
Area Forecast Discussion
National Weather Service Medford OR
323 AM PDT THU JUL 28 2016
.SHORT TERM...A broad upper level ridge will remain in place over
the region through Friday. At the surface, high pressure offshore
and a thermal trough along the coast will bringing gusty
northeast flow to the coastal mountains and gusty northerly winds
during the afternoon and evening to the coast. Hot temperatures
are expected inland through Friday. Conditions will be dry today
then some mid level monsoon moisture is forecast to move into the
area Friday and may bring a slight chance for thunderstorms to
southern portions of the area. An upper trough will move inland
north of the area late Friday and Saturday then remain in place on
Sunday. This will bring slightly cooler temperatures on the
weekend. Additionally ahead of the front, gusty winds and
thunderstorms are possible east of the Cascades on Saturday.
Today, the main focus remains on the hot and dry conditions.
Temperatures are expected to warm into the triple digits for valley
locations across Northern California and into the Rogue, Illinois
and Applegate Valleys in Southern Oregon. Other inland valleys in
Southern oregon will see highs in the mid to upper 90s.
These hot temperatures continue into Friday. Additionally, some
mid level moisture moving up from the south may come into play on
Friday and will bring a slight chance for thunderstorms in
portions of Siskiyou County, Modoc County and southern Klamath
County. There is high confidence that there will be cumulus build
ups Friday afternoon into Friday evening. Models support a slight
chance for thunderstorms as well, showing mid level moisture
advection and weak instability moving into southern portions of
the CWA. Of note, the models continue to show only weak shortwave
triggers moving into the area on Friday, which may limit the
thunderstorm potential. Have leaned towards the slight chance for
storms given the monsoon moisture and potential for s high based
thunderstorms which may produce gusty outflow winds. Additionally,
any storms that develop over eastern portions of the area may not
have significant rain with them, especially over the Modoc County
area where cloud bases are forecast to be high, sub cloud
conditions are dry and storms motion is expected to be around 10
kts. In Siskiyou County, expect any storms that form to be slow
On Saturday, an upper trough will move inland to the north and a
front will push into the area. The front combined with lingering
mid level moisture and instability will bring a chance for
thunderstorms for areas east of the Cascades in Eastern Siskiyou,
Modoc, Southern Klamath and Southern Lake Counties. Additionally
winds are forecast to increase and become gusty east of the
Cascades late Saturday afternoon and evening. Temperatures will
be slightly cooler on Saturday over the area as the upper trough
moves inland but still expect very warm temperatures in the 90s
for most inland valleys.
Somewhat cooler conditions will develop on Sunday with high
temperatures in the mid 80s to mid 90s for most inland valleys.
Although relatively cooler, temperatures will still be above
normal by about 3 to 5 degrees on Sunday. Early in the day, expect
a marine push of low clouds along the Coos and Douglas County
coast and into the Umpqua Valley Saturday night into Sunday
morning. These clouds will clear off during the day Sunday.
.LONG TERM...Another trough is expected to move inland north of
the area on Monday and Tuesday then shift eastward on Wednesday.
This pattern will bring sightly above normal to near normal
temperatures early next week. Conditions are expected to remain
dry. Additionally, expect gusty west winds on Monday ahead of
this next trough with strongest winds east of the Cascades in the
late afternoon and evening.
.AVIATION...28/00Z TAF cycle...Inland VFR conditions will continue
for the next 24 hours. Marine stratus will persist at the coast from
Cape Blanco northward and into the Coquille Valley through around
16Z Thursday morning then begin to erode back into the coastal
waters. Stratus will surge back into the same areas Thursday
evening. Moderate to strong and gusty northerly winds are expected
for most areas along the coast and offshore, though with a decrease
during the early morning hours. -DW
.MARINE...Updated 1030 PM PDT Wednesday, 27 July 2016...
The current pattern of a thermal trough along the coast and high
pressure offshore will persist at least into early next week with
strong north winds and steep to very steep wind driven seas.
Conditions will be most hazardous south of Cape Blanco beyond 5 NM
from shore. Winds are expected to weaken slightly on Monday. -DW
Pacific Coastal Waters...Small Craft Advisory for winds until 11 PM PDT Sunday for
Small Craft Advisory until 11 PM PDT Sunday for
Hazardous Seas Warning until 11 PM PDT Sunday for PZZ356-376.
Small Craft Advisory for winds until 11 PM PDT Friday for
Hazardous Seas Warning until 11 PM PDT Friday for PZZ370.
Gale Warning until 11 PM PDT Sunday for PZZ376.