Area Forecast Discussion
Issued by NWS Medford, OR

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061
FXUS66 KMFR 131650
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
850 AM PST SAT FEB 13 2016

.SHORT TERM...DRY WEATHER WILL CONTINUE THROUGH THIS MORNING THEN
A WARM FRONT WILL PUSH INLAND JUST NORTH OF THE AREA THIS
AFTERNOON AND SHIFT SOUTH INTO SOUTHERN OREGON THIS EVENING
FOLLOWED BY AN OCCLUDING FRONT MOVING INLAND LATE THIS EVENING
AND TONIGHT. THIS FRONTAL SYSTEM WILL CONTINUE TO IMPACT THE AREA
SUNDAY MORNING THEN GRADUALLY SHIFT EAST SUNDAY AFTERNOON AND
EVENING WHILE AN UPPER RIDGE BUILDS INTO THE AREA.

THIS MORNING, EXPECT AREAS OF FOG IN WESTERN VALLEYS, INCLUDING
THE ILLINOIS, APPLEGATE, ROGUE AND KLAMATH RIVER VALLEYS. AREAS OF
DENSE FOG ARE EXPECTED DURING THE EARLY MORNING. LOW CLOUDS AND
PATCHY FOG ARE EXPECTED THROUGH THE MORNING IN THE UMPQUA VALLEY
AS WELL AS ALONG THE COAST NORTH OF CAPE BLANCO. THE LOW CLOUDS
AND FOG WILL CLEAR LATE THIS MORNING INTO EARLY AFTERNOON.
HOWEVER, HIGH CLOUDS WILL MOVE INTO THE AREA DURING THIS PERIOD.

MODEL FORECASTS CONTINUE TO SHOW THE WARM FRONT MOVING INTO AREAS
TO NORTH THIS AFTERNOON WITH RAIN SPREADING INTO PORTIONS OF COOS
AND NORTHWEST DOUGLAS COUNTY. THEN DURING THE EVENING AND NIGHT
EXPECT THE FRONTAL SYSTEM TO SHIFT SOUTHWARD AND SPREAD LIGHT TO
MODERATE PRECIPITATION ACROSS MUCH OF SOUTHWEST OREGON WITH AREAS
OF LIGHT PRECIPITATION EAST OF THE CASCADES AND INTO NORTHERN
CALIFORNIA. WIDESPREAD PRECIPITATION WILL CONTINUE THROUGH SUNDAY
MORNING THEN EXPECT CONTINUED AREAS OF RAIN THROUGH SUNDAY
AFTERNOON, ESPECIALLY ALONG AND WEST OF THE CASCADES. SHOWERS
WILL DECREASE SUNDAY EVENING AS AN UPPER LEVEL RIDGE BUILDS INTO
THE REGION FROM THE WEST SOUTHWEST. SNOW LEVELS ARE EXPECTED TO BE
HIGH DURING THIS EVENING...AND EXPECT SNOW ACCUMULATIONS TO BE
LIMITED MAINLY TO A FEW AREAS IN THE SOUTHERN OREGON CASCADES.
SNOW LEVELS ARE FORECAST TO START OUT AROUND 5500 TO 6500 FEET
THIS EVENING RISING TO AROUND 7000 FEET OR HIGHER TONIGHT...THEN
REACHING 8000 FEET BY SUNDAY AFTERNOON. EXPECT SOME LIGHT SNOW
ACCUMULATIONS IN THE SOUTHERN OREGON CASCADES TONIGHT, MAINLY
ABOVE 6000 FEET FROM CRATER LAKE NORTH, THEN CHANGING TO RAIN
SUNDAY.

MODELS CONTINUE TO SUPPORT BREEZY SOUTHWEST TO WEST WINDS IN THE
MOUNTAINS TONIGHT AND SUNDAY WITH THIS FRONTAL SYSTEM. MAY ALSO
SEE SOME BREEZY WINDS IN THE SUMMER LAKE AREA WITH GUSTS TO AROUND
40 MPH. WINDS ARE EXPECTED TO PEAK TONIGHT AND SUNDAY MORNING.


&&

.AVIATION...FOR THE 13/12Z TAF CYCLE...IFR CONDITIONS ARE BEING
OBSERVED IN MANY WEST SIDE VALLEY AND COASTAL LOCATIONS THIS
MORNING...AND SHOULD IMPROVE LATE THIS MORNING OR EARLY AFTERNOON.
EARLIER CLEARING IS EXPECTED AT THE COAST. A WARM FRONT WILL BRING
LIGHT TO MODERATE PRECIPITATION THIS EVENING INTO SUNDAY...PRIMARILY
TO AREAS FROM THE CASCADES WEST. MOUNTAIN OBSCURATION WILL SPREAD
INLAND LATE THIS AFTERNOON INTO THE EVENING. CONDITIONS FROM THE
UMPQUA BASIN WESTWARD TO THE COAST WILL RETURN TO A MIX OF MVFR AND
IFR THIS EVENING...WHILE TERMINALS EAST LIKE MFR AND LMT SHOULD BE
REMAIN VFR THIS EVENING. SK


&&

.MARINE...UPDATED 800 AM PST SAT FEB 13 2016...MODERATE WEST SWELL
WILL CONTINUE OVER ALL WATERS THROUGH THE WEEKEND. A COLD FRONT WILL
BRING A PERIOD OF MODERATE SOUTH WINDS THIS AFTERNOON, WHICH WILL
MAKE FOR INCREASINGLY STEEP SEAS THROUGH TONIGHT. THE STRONGEST
WINDS AND STEEPEST SEAS ARE EXPECTED FROM CAPE BLANCO NORTHWARD.
WINDS AND SEAS WILL BE LIGHTER SUNDAY NIGHT THROUGH TUESDAY,
GENERALLY BELOW 15 KT AND 10 FT. THE NEXT FRONT IS EXPECTED
WEDNESDAY FOLLOWED BY ANOTHER POTENTIALLY STRONGER FRONT FRIDAY.
-BPN


&&

.PREV DISCUSSION... /ISSUED 0515 AM PST SAT FEB 13 2016/

UPDATED AVIATION DISCUSSION.

DISCUSSION...A FAST MOVING JET STREAM IS DRIVING A FRONTAL
BOUNDARY TOWARD NORTHERN PART OF OREGON. FIRST THE WARM FRONT PART
OF THE SYSTEM WILL CLIP THE NORTHERN PART OF OUR FORECAST AREA
FROM COOS INTO NORTHERN DOUGLAS COUNTY THIS AFTERNOON. THE REST OF
OUR AREA WILL SEE MAINLY INCREASE IN HIGH CLOUDS. SATELLITE
IMAGERY SHOWS FOG AND LOW CLOUDS HAVE FORMED IN THE WESTERN
VALLEYS INCLUDING THE KLAMATH RIVER VALLEY. WITH THE WARM FRONT
MOVING ACROSS TODAY, THE FOG AND LOW CLOUDS MAY LINGER LONGER THAN
NORMAL AND SOME AREAS MAY NOT CLEAR UNTIL NOON.

THE COLD FRONT IS EXPECTED TO COME INLAND THIS EVENING. AROUND A
QUARTER OF AN INCH OF RAIN IS EXPECTED AT NORTH BEND AND AROUND
0.20 IN ROSEBURG. LIGHT RAIN IS EXPECTED TO SPREAD INTO THE ROGUE
VALLEY AFTER MIDNIGHT. WITH THE SNOW LEVELS IN THE 6-7000 FT
RANGE..ONLY THE HIGH PEAKS WILL SEE SNOW AND WE ARE FORECAST 2-3
INCHES OF NEW SNOW AT CRATER LAKE. RAIN IS EXPECTED TO CONTINUE
INTO SUNDAY MORNING. RAINFALL TOTAL FROM TONIGHT THROUGH THE END
OF THE DAY ON SUNDAY RANGES FROM ALMOST HALF AN INCH IN COOS
COUNTY AND EASTERN DOUGLAS COUNTY TO ABOUT THREE QUARTERS OF AN
INCH IN THE CASCADES FROM LAKE OF THE WOODS NORTH. THE ROGUE
VALLEY CAN EXPECT ABOUT A TENTH...THE KLAMATH BASIN AROUND 0.05 IN
GENERAL. THE REMAINDER OF OUR FORECAST AREA IN THE EASTERN OREGON
AND NORTHERN CALIFORNIA WILL SEE MAINLY LIGHT SHOWERS WITH AMOUNT
UP TO 0.05 INCH.

THE EARLY PART OF NEXT WEEK STILL LOOKS DRY AS A RIDGE OF HIGH
PRESSURE BUILDS NORTHWARD ALONG THE WEST COAST. CONFIDENCE IS
FAIRLY HIGH ON THIS DRY FORECAST. WE HAVE INTRODUCED A RAIN CHANCE
ON WEDNESDAY AS MODELS CONTINUE TO SHOW THE RIDGE WEAKENING IN
RESPONSE TO UPSTREAM TROUGHS. CONFIDENCE IS HIGHER FOR CHANCE OF
RAIN/SNOW NEXT THURSDAY PER BOTH THE GFS AND ECMWF SHOWING A
TROUGH OVER OUR AREA. THINGS LOOK MORE FAVORABLE FOR US TO SEE
MEASURABLE PRECIPITATION IN THE SECOND HALF OF NEXT WEEK INTO NEXT
WEEKEND ALTHOUGH AMOUNTS APPEAR LIGHT WITH EACH FRONT. /FB


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING FOR ORZ024-026.

CA...NONE.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 PM PST SUNDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM PST SUNDAY
     FOR PZZ350-370.

$$

CC



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