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000
FXUS66 KMFR 110335
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
835 PM PDT MON MAR 10 2014

.DISCUSSION...A SHORT WAVE WILL SLIP SOUTHWARD FROM EASTERN
OREGON INTO NORTHERN NEVADA TONIGHT INTO TUESDAY MORNING WHILE
HEIGHTS GRADUALLY RISE ALONG THE WEST COAST. THIS WILL ALLOW
REMAINING CLOUDS THIS EVENING TO MOSTLY DISSIPATE IN SW OREGON
AND N CALIFORNIA. IT WILL BE COOLER/DRIER THAN RECENT NIGHTS WITH
LOW TEMPERATURES A COUPLE OF DEGREES LOWER THAN THE SEASONAL
AVERAGES. THIS MEANS LOW TO MID 30S IN MEDFORD AND MID 20S IN
KLAMATH FALLS. DUE TO THE RECENT RAINFALL, PATCHY FOG OR LOW
CLOUDS MAY DEVELOP OVER SOME OF THE WEST SIDE VALLEYS TOWARD
SUNRISE.

SURFACE HIGH PRESSURE WILL BUILD INTO NORTHERN OREGON AND
WASHINGTON TUESDAY RESULTING IN SUNNY, DRY WEATHER HERE. THIS WILL
ALSO INDUCE A THERMAL TROUGH ALONG THE NORTHERN CALIFORNIA AND
SOUTHWEST OREGON COASTS. AS A RESULT, EXPECT ENHANCED NORTHEAST TO
EAST BREEZES OVER THE AREA...ESPECIALLY THE HIGHER TERRAIN AND
THE EAST SIDE. AN INVERSION WILL STRENGTHEN TUESDAY NIGHT, KEEPING
BREEZES UP AT MID SLOPE AND RIDGE LEVEL WHILE VALLEY LOCATIONS
DECOUPLE AND TURN QUITE CHILLY. THE OFFSHORE GRADIENT WILL EASE
WEDNESDAY AND IT WILL TURN MILDER. A DRY, WARM WEATHER PATTERN IS
EXPECTED TO PERSIST LATE THIS WEEK. SPILDE

&&

.AVIATION...BASED ON THE 11/00Z TAF CYCLE...

CONDITIONS ARE VFR ACROSS THE AREA WITH ISOLATED MOUNTAIN
OBSCURATIONS FROM THE CASCADES EAST. EXPECT SKIES TO CLEAR
OVERNIGHT. BUT, WITH PLENTY OF LOW LEVEL MOISTURE REMAINING IN
THE VALLEYS...AREAS OF IFR CIGS IN LOW CLOUDS AND/OR FOG ARE
EXPECTED TO DEVELOP IN VALLEYS WEST OF THE CASCADES LATE TONIGHT
BETWEEN 09-12Z AND CONTINUE THROUGH AROUND 17-18Z. BEST CHANCE FOR
IFR CIGS AND VISIBILITIES IS IN THE UMPQUA BASIN, INCLUDING KRBG,
AND IN THE LOWER ROGUE VALLEY AND IN THE ILLINOIS VALLEY. ISOLATED
LOCATIONS ALONG THE COAST MAY SEE BRIEF IFR/MVFR CONDITIONS AS
WELL DURING THE EARLY MORNING. /CC

&&

.MARINE...MODERATE WEST SWELL IS DIMINISHING TONIGHT INTO TUESDAY.
HOWEVER SEAS WILL INCREASE AND BECOME STEEP TO VERY STEEP TUESDAY
DUE TO MODERATE NORTH TO NORTHEAST WINDS DEVELOPING. GUSTY NORTH TO
NORTHEAST WINDS WILL PEAK AT SMALL CRAFT ADVISORY LEVELS OF 25 TO 30
KT TUESDAY AFTERNOON AND EVENING THEN TAPER OFF TUESDAY NIGHT INTO
WEDNESDAY MORNING. WINDS WILL BE STRONGEST BEYOND 5 NM FROM SHORE IN
THE AREA FROM CAPE BLANCO SOUTHWARD, WHERE GUSTS MAY REACH GALE
FORCE 35 KT TUESDAY AFTERNOON AND EVENING. 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 WARNING LEVELS.

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 LATE TUESDAY 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.  /CC

&&

.PREV DISCUSSION... /ISSUED 304 PM PDT MON MAR 10 2014/

SHORT TERM...ISOLATED MOUNTAIN SHOWERS WILL CONTINUE THIS
AFTERNOON BUT THEY ARE EXPECTED TO DISSIPATE THIS EVENING. NORTH
TO NORTHWEST FLOW ALOFT WILL SET UP ON TUESDAY AS HIGH PRESSURE
BUILDS INTO SOUTHERN OREGON. AT THE SURFACE A THERMAL TROUGH WILL
BUILD ALONG THE COAST TUESDAY NIGHT. THIS WILL SET UP A MINOR
BROOKINGS EFFECT, ENOUGH OFFSHORE FLOW FOR SOUTHERN CURRY COUNTY TO
REMAIN MILD FOR TUESDAY AND TUESDAY NIGHT. SINCE TEMPERATURES AT
850MB STARTS OFF RELATIVELY COOL, THE WARMING IN THE CHETCO RIVER
VALLEY IS NOT EXPECTED TO BE THAT STRONG. MOREOVER THIS OFFSHORE
FLOW WILL BE SHORT LIVED AS UPSTREAM SHORT WAVE TROUGH HELPS TO
WEAKEN THE RIDGE. WE MAY SEE LOW CLOUDS SURGING UP THE COAST
WEDNESDAY. /FB

LONG TERM...

THE REMAINDER OF THE WEEK WILL BE WARM...DRY AND STABLE AS RIDGING
RETURNS. THIS WILL STRENGTHEN NIGHTTIME VALLEY INVERSION. EXPECT
COOL NIGHT TIME TEMPERATURE THROUGH THE MIDDLE OF THE WEEK. IN THE
SECOND HALF OF THE WEEK TEMPERATURES WILL BE WARMING WITH HIGHS
POSSIBLY REACHING LOWER 70S FOR SW OREGON VALLEY AROUND NEXT
SATURDAY. BEYOND SATURDAY THE MODELS BEGIN TO DIVERGE WITH THE
ECMWF WANTING TO BRING A TROUGH INLAND. CONFIDENCE IS NOT VERY
HIGH ON THIS SCENARIO AS THE PRECEDING RIDGE APPEARS STRONG. HAVE
TRENDED BACK ON THE POPS ON DAY 6-7 TO MAINLY SLIGHT CHANCE. /FB

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS FROM 2 PM
     TUESDAY TO 5 AM PDT WEDNESDAY FOR PZZ350-356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 2 PM TUESDAY TO 5
     AM PDT WEDNESDAY FOR PZZ350-356-370.
     SMALL CRAFT ADVISORY FOR WINDS FROM 8 AM TUESDAY TO 5 AM PDT
     WEDNESDAY FOR PZZ376.
     HAZARDOUS SEAS WARNING FROM 2 PM TO 11 PM PDT TUESDAY FOR
     PZZ376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 8 AM TUESDAY TO 5
     AM PDT WEDNESDAY FOR PZZ376.

$$

MAS/DW/FJB/CC