482
FXUS66 KMFR 180536
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
1036 PM PDT SAT MAY 17 2025
DISCUSSION...UPDATED AVIATION AND MARINE SECTION
AVIATION...(06Z TAFS)
SHOWERS ARE STILL PRESENT NEAR THE CASCADES
AND A FEW MORE WILL PASS THROUGH WEST OF THE CASCADES TONIGHT. VFR
CONDITIONS WILL PREVAIL INLAND WITH A MIXTURE OF MVFR/VFR AT THE
COAST, INCLUDING KOTH. FOR NOW, KEEPING SCATTERED MVFR IN THE UMPQUA
BASIN INCLUDING KRBG TONIGHT, BUT WILL MONITOR IF IT DEVELOPS
FURTHER. THE MVFR CONDITIONS AT THE COAST WILL IMPROVE THROUGH THE
MORNING. NORTHWEST WINDS WILL PICK UP AGAIN TOMORROW, ESPECIALLY
EAST OF THE CASCADES WITH GUSTS NEAR 20-30 KT POSSIBLE IN THE
AFTERNOON.
-GUERRERO/HERMANSEN
MARINE...UPDATED 830 PM SATURDAY, MAY 17, 2025
EXPECTING
RELATIVELY QUIET CONDITIONS THROUGH THE REMAINDER OF THE WEEKEND. A
WEAK FRONTAL SYSTEM WILL MOVE THROUGH THE AREA MONDAY AFTERNOON WITH
WINDS VEERING FROM THE SOUTH TO NORTHWEST. THESE NORTHERLY WINDS
WILL INCREASE ON TUESDAY IN CONJUNCTION WITH THE DEVELOPMENT OF A
THERMAL TROUGH. BUILDING SEAS ON TUESDAY MAY BECOME HIGH AND STEEP
WITH THE COMBINATION OF WIND WAVES AND A BUILDING WEST-NORTHWEST
SWELL AROUND 13 SECONDS. CONDITIONS MAY IMPROVE SLIGHTLY STARTING
WEDNESDAY AND CONTINUE THROUGH LATER PARTS OF THE WEEK.
-GUERRERO/HERMANSEN
PREV DISCUSSION
/ISSUED 204 PM PDT SAT MAY 17 2025/
DISCUSSION...SHOWERS CONTINUE UNDER A PASSING UPPER TROUGH THIS
AFTERNOON. AMOUNTS WILL BE GENERALLY LIGHT, WITH MORE CONSTANT
SHOWERS OVER THE CASCADES, THE WARNER MOUNTAINS, AND SOUTHERN LAKE
COUNTY. SLIGHT THUNDERSTORM CHANCES REMAIN IN THE FORECAST FOR
DOUGLAS AND JACKSON COUNTY (10-15%) AS WELL AS EAST MODOC AND
SOUTHEAST LAKE COUNTIES (15-20%). ANY THUNDERSTORMS THAT DO DEVELOP
THIS AFTERNOON AND EVENING ARE MOST LIKELY TO BE ISOLATED AND NOT
SEVERE. GUSTY WINDS, LOCALLY HEAVY SHOWERS, AND CLOUD-TO-GROUND
LIGHTNING STRIKES MAY BE POSSIBLE. LATE NIGHT SNOW SHOWERS ARE
POSSIBLE OVER THE HIGHEST ELEVATIONS OF THE CASCADES, BUT
ACCUMULATION AT PASS LEVELS IS NOT EXPECTED.
ACTIVITY DECREASES OVERNIGHT INTO SUNDAY, WITH A FEW LAST SHOWERS
POSSIBLY LINGERING OVER DOUGLAS COUNTY OR THE CASCADES UNTIL THE
AFTERNOON. DAYTIME HIGHS WILL INCREASE A FEW DEGREES FOR WEST SIDE
VALLEYS, BUT TEMPERATURES WILL STAY BELOW SEASONAL LEVELS.
CONDITIONS THROUGH THE WEEK LOOK TO BE DEFINED BY ZONAL FLOW ALOFT.
TEMPERATURES RISE TO SEASONAL LEVELS ON MONDAY, WITH MID 60S ALONG
THE OREGON COAST AND LOW TO MID 70S FOR WEST SIDE VALLEYS. EAST SIDE
AREAS LOOK TO BE IN THE MID TO HIGH 60S. A WEAK FRONT LOOKS TO BRING
LIGHT SHOWERS TO COOS, CURRY, AND DOUGLAS COUNTIES AS WELL AS THE
CASCADES THROUGH THE DAY MONDAY. A BUNDLE OF UPPER LEVEL INSTABILITY
LOOKS TO PASS OVER THE AREA ON LATE WEDNESDAY OR EARLY THURSDAY, BUT
EXPECTED DRY CONDITIONS OFFER LITTLE TO FUEL ANY DEVELOPMENT.
ISOLATED OR SCATTERED SHOWERS ARE POSSIBLE WEST OF THE CASCADES, BUT
CHANCES ARE MODERATE TO LOW (10-50%). BY FRIDAY, WEST SIDE VALLEYS
WARM TO MID TO HIGH 70S, WITH HIGH 60S TO MID 70S EAST OF THE
CASCADES.
AN UPPER RIDGE LOOKS TO DEVELOP OVER THE WEEKEND, BRINGING A PERIOD
OF DRY, STABLE WEATHER. ADDITIONAL WARMING IS POSSIBLE ON SATURDAY,
WHILE GUIDANCE POINTS TO SUNDAY BEING NOTICEABLY WARMER. THERE'S
STILL SOME UNCERTAINTY WITH HOW WARM TEMPERATURES WILL GET OVER THE
WEEKEND , WHICH DEPENDS ON WHERE THE RIDGE DEVELOPS. USING MEDFORD
AS AN EXAMPLE, ECMWF AND GFS METEOGRAMS FAVOR HIGH 70S TO MID 80S
WHILE NBM PROBABILISTIC GUIDANCE HAS A 55% CHANCE FOR SUNDAY HIGHS
TO EXCEED 85 DEGREES. THE FORECAST BEYOND NEXT SUNDAY REMAINS
UNCERTAIN AS WELL, WITH ECMWF METEOGRAM GUIDANCE STARTING TO SHOW
UNIFORM SIGNALS FOR LIGHT SHOWERS AT NORTH BEND FOR MEMORIAL DAY.
THE GFS AND NBM SHOW LOWER CHANCES BUT THE CHANCES THAT DO APPEAR
MATCH UP WELL WITH THE ECMWF. -TAD
MFR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page