124
FXUS66 KMFR 272023
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
123 PM PDT MON APR 27 2026
DISCUSSION
SATELLITE IMAGERY THIS AFTERNOON SHOWS QUITE A BIT
OF CLOUD COVER AROUND THE REGION. MARINE STRATUS FROM THIS
MORNING IS ERODING FROM PORTIONS OF DOUGLAS AND COOS COUNTIES.
MEANWHILE, AN EXPANSIVE CUMULUS FIELD HAS DEVELOPED EAST OF THE
CASCADES AND OVER THE HIGH TERRAIN OF NORTHERN CALIFORNIA AND
SOUTHWEST OREGON ALONG AND SOUTH OF THE ROGUE-UMPQUA DIVIDE. RADAR
SHOWS WIDESPREAD SHOWERS EAST OF THE CASCADES AND SOUTH INTO
MODOC/EASTERN SISKIYOU COUNTIES, WITH SOME SHOWERS DEVELOPING OVER
WESTERN SISKIYOU COUNTY. THE LIGHTNING POTENTIAL IS PRETTY LOW
TODAY (10-15% CHANCE), FOCUSED ACROSS SOUTHERN SISKIYOU/MODOC
COUNTIES. CONVECTIVE PARAMETERS ARE FAIRLY MEAGER TODAY, SO ONLY
ISOLATED STRIKES ARE EXPECTED TODAY.
A SHORTWAVE TROUGH IS DROPPING SOUTH THROUGH THE REGION TODAY, JUST
OFFSHORE, AND THIS WILL HELP KEEP SHOWER ACTIVITY GOING ON THROUGH
THE AFTERNOON. AFTERNOON TEMPERATURES TODAY WILL BE NEAR TO JUST
BELOW SEASONAL NORMALS WITH SOME FAIRLY TYPICAL AFTERNOON BREEZES
(ASIDE FROM SOME GUSTIER WINDS WITH SHOWERS). TONIGHT WILL BE MUCH
LIKE LAST NIGHT. SHOWER ACTIVITY WILL WANE AFTER SUNSET AND THERE
SHOULD BE ANOTHER DECENT MARINE PUSH THAT BRINGS STRATUS BACK TO THE
COAST AND INTO THE UMPQUA BASIN. THE MARINE LAYER DOESN'T LOOK QUITE
AS DEEP AS THIS MORNING, SO CLOUD COVERAGE SHOULD BE A BIT LESS.
DRIER CONDITIONS ARE EXPECTED ON TUESDAY. THERE IS ONE MORE
SHORTWAVE THAT MOVES THROUGH THE REGION, BUT MID-LEVEL MOISTURE
DECREASES, AND THE MORE FAVORABLE INSTABILITY MOVES TO THE SOUTH AND
EAST OF THE FORECAST AREA. THERE COULD BE SOME ISOLATED SHOWERS
ACROSS SOUTHERN MODOC/SISKIYOU COUNTIES TUESDAY AFTERNOON, BUT MOST
AREAS WILL REMAIN DRY UNDER PARTLY TO MOSTLY CLOUDY SKIES. AFTERNOON
TEMPERATURES TREND WARMER BY AROUND 5 TO 7 DEGREES ON TUESDAY, AND
THIS WARMING TREND CONTINUES THROUGH THE REMAINDER OF THE WEEK.
UPPER LEVEL RIDGING BUILDS INTO THE REGION WEDNESDAY AND THEN
PERSISTS THROUGH AT LEAST FRIDAY/SATURDAY. THIS BRING A PERIOD OF
DRY AND WARMER WEATHER WITH HIGH TEMPERATURES (AREAS INLAND FROM THE
COAST) GENERALLY 10-15F ABOVE NORMAL FOR LATE APRIL/EARLY MAY. THIS
MEANS HIGH TEMPERATURES RANGING FROM 75-85F (70-75F) FOR MOST INLAND
WEST (EAST) SIDE VALLEYS. COASTAL AREAS COULD CONTINUE TO EXPERIENCE
INTRUSIONS OF LATE-NIGHT/MORNING MARINE STRATUS.
MODELS THEN SHOW THE RIDGE BREAKING DOWN LATE THIS WEEKEND AS AN
UPPER TROUGH JUST OFF THE WEST COAST TRIES TO CLOSE OFF OFFSHORE. AN
INCREASING NUMBER OF SOLUTIONS SHOW THE LOW CLOSING OFF TO OUR SW,
WHICH WOULD BRING AN INCREASED RISK FOR MAINLY AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS AS EARLY AS SATURDAY AFTERNOON, WITH THE
POTENTIAL FOR ACTIVE WEATHER PERSISTING SUNDAY INTO EARLY NEXT WEEK.
MUCH WILL DEPEND ON THE EVENTUAL TRACK OF TROUGH/LOW, HOWEVER. MANY
MEMBERS, PARTICULARLY FROM THE GEFS ENSEMBLES, MAINTAIN A WEAKER
TROUGH MOVING THROUGH, WHICH WOULD LIMIT THE OVERALL EXTENT/COVERAGE
OF PRECIPITATION. WE'LL ADJUST THE FORECAST AS THINGS COME MORE INTO
FOCUS. -SPILDE/BR-Y
AVIATION...27/18Z TAFS
ONSHORE FLOW HAS BROUGHT MVFR CEILINGS AND
TERRAIN OBSCURATIONS TO THE OREGON COAST AND THE COASTAL MOUNTAINS,
AND INLAND INTO THE UMPQUA VALLEY (INCLUDING ROSEBURG). THIS WILL
SLOWLY CLEAR LATE THIS MORNING INTO EARLY THIS AFTERNOON BETWEEN 18-
21Z.
IN NORTHERN CALIFORNIA AND OVER THE EAST SIDE, SHOWERS WILL RETURN
THIS AFTERNOON, BUT COVERAGE SHOULD BE MORE SCATTERED. LOCAL
MVFR/IFR CONDITIONS WITH TERRAIN OBSTRUCTIONS ARE POSSIBLE IN ANY
HEAVIER SHOWERS. OTHERWISE AND ELSEWHERE, VFR WILL PREVAIL THROUGH
THIS EVENING.
ADDITIONAL IFR/MVFR CEILINGS WILL RETURN TO THE COAST AND UMPQUA
LATER THIS EVENING AND OVERNIGHT.
MARINE...UPDATED 100 PM PDT MONDAY, APRIL 27, 2026
NORTH WINDS
CONTINUE THIS WEEK. INITIALLY, WINDS STAY BELOW ADVISORY SPEEDS
TODAY. THEN, GUSTY NORTH WINDS DEVELOP ON TUESDAY MORNING SOUTH OF
CAPE BLANCO. STEEP SEA RETURN BY TUESDAY AFTERNOON FOR THE WATERS
SOUTH OF CAPE BLANCO. NORTH WINDS WILL LIKELY STRENGTHEN ACROSS
THE WATERS WEDNESDAY WITH VERY STEEP SEAS POSSIBLE FOR THE WATERS
SOUTH OF CAPE BLANCO AND STEEP SEAS NORTH OF CAPE BLANCO. THESE
CONDITIONS MAY LINGER INTO THURSDAY. WINDS TREND SLIGHTLY LOWER
FRIDAY AND SATURDAY BUT SEAS MAY REMAIN STEEP.
MFR WATCHES/WARNINGS/ADVISORIES
OR...CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FROM 11 AM TUESDAY TO
11 PM PDT WEDNESDAY FOR PZZ350-356-370-376.
HAZARDOUS SEAS WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
EVENING FOR PZZ356-376.
MNF/CC
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