000
FXUS66 KMFR 251500
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
800 AM PDT SAT MAY 25 2013
.DISCUSSION...PARTLY CLOUDY SKIES THIS MORNING OVER THE
COAST...COAST RANGE...AND UMPQUA BASIN...AND MOSTLY CLEAR SKIES
OVER THE REMAINDER OF THE CWA. A FEW STATIONS IN THE COAST RANGE
IN CURRY COUNTY REPORTED 0.01 INCHES IN THE PAST SIX HOURS. OTHER
THAN THAT IT HAS BEEN DRY. THE SHORT WAVE THAT PASSED THROUGH
LAST NIGHT DIDN`T DO MUCH OF ANYTHING IN THE PRECIPITATION
DEPARTMENT AS IT WAS TIMED WITH MINIMAL SURFACE HEATING.
A LONG WAVE TROUGH REMAINS OVER THE PACIFIC NORTHWEST THIS
MORNING...AND A SHORT WAVE ROTATING AROUND THE LOW WILL MOVE
ONSHORE LATE TONIGHT. THIS ONE IS STRONGER THAN THE ONE THAT JUST
PASSED THROUGH...SO IT WILL LIKELY HAVE SOME ASSOCIATED LIGHT
PRECIPITATION. IT WILL DEVELOP AT THE COAST THIS EVENING AND
SPREAD INLAND TONIGHT. THE BULK OF IT WILL FALL ALONG THE
COAST..COAST RANGE...AND UMPQUA BASIN. THERE ARE SOME
AFTERNOON/EVENING THUNDERSTORMS IN THE FORECAST BOTH TODAY AND
SUNDAY AND THIS WILL BE REEVALUATED LATER TODAY.
BOTH THE SHORT WAVE AND THE PARENT TROUGH WILL MOVE OUT TO THE
EAST SUNDAY EVENING AND A WEAK SHORT WAVE RIDGE WILL BRIEFLY BUILD
INTO THE AREA SUNDAY NIGHT. THIS WILL BREAK DOWN QUICKLY AND
ANOTHER TROUGH WILL MOVE ONSHORE MONDAY. THIS SYSTEM WILL BE THE
BIGGEST RAIN MAKER OF THE WEEK. RAIN WILL DEVELOP ALONG THE COAST
EARLY MONDAY MORNING...SPREADING INLAND DURING THE DAY. UNLIKE THE
PREVIOUS SYSTEM...JUST ABOUT THE ENTIRE MEDFORD CWA WILL SEE SOME
PRECIPITATION FROM THIS SYSTEM.
THE UPPER TROUGH WILL MOVE OUT TO THE EAST MONDAY NIGHT...THOUGH
SOME SHOWERS WILL PERSIST THROUGH TUESDAY DUE TO SHORT WAVES
MOVING DOWN THE BACK SIDE OF THE TROUGH. ROUGHLY ZONAL FLOW ALOFT
WILL DEVELOP IN ITS WAKE AND ONE MORE EMBEDDED SHORT WAVE WILL
MOVE ONSHORE TUESDAY NIGHT INTO WEDNESDAY MORNING FOR ANOTHER
ROUND OF SHOWERS. AFTER THAT A LONG WAVE RIDGE WILL BUILD INTO THE
AREA AND THURSDAY AND FRIDAY LOOK TO BE MOSTLY DRY WITH INLAND
TEMPERATURES WARMING UP TO NEAR NORMAL VALUES.
THE NEXT CHANCE OF PRECIPITATION LOOKS TO BE NEXT SATURDAY WHEN
ANOTHER WEAK WAVE WILL MOVE IN...BUT AT THIS TIME IT DOESN`T LOOK
LIKE MUCH OF A CHANCE.
&&
.AVIATION...BASED ON THE 25/12Z TAF CYCLE.
EXPECT VFR CONDITIONS INTO THIS EVENING FOR THE ROGUE VALLEY AND
AREAS EAST OF THE CASCADES. ELSEWHERE...AREAS IN THE UMPQUA VALLEY
AND COAST WILL SEE AREAS OF MVFR/IFR THROUGH 17Z THIS MORNING THEN
VFR CONDITIONS FOR MUCH OF THE AFTERNOON. MVFR CIGS WILL DEVELOP
AROUND 00Z ALONG THE COAST AND THEN SPREAD INTO THE UMPQUA VALLEY BY
06Z. CLOUDS WILL ALSO BANK UP AGAINST THE MOUNTAINS RESULTING IN
TERRAIN OBSCURATIONS.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
15/15/15
000
FXUS66 KMFR 251000
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
300 AM PDT SAT MAY 25 2013
.DISCUSSION...THE TRADITIONAL START TO THE CAMPING SEASON STARTS
OFF WET WITH PERIODS OF SUN. THE FIRST SYSTEM MOVES INTO THE
REGION THIS AFTERNOON WITH A LONG FETCH OF MOISTURE IN THE
SOUTHERLY WARM CONVEYOR FLOW BRINGING DECENT MOISTURE INTO THE
REGION. THIS FLOW BRINGS INSTABILITY TO THE EAST SIDE WITH A
SLIGHT CHANCE OF THUNDERSTORMS TO THE NORTHERN EAST SIDE AND
NORTHERN CASCADES. SHOWERS LINGER BEHIND THE FRONT ON SUNDAY WITH
A LEFT EXIT REGION OF A 70 KT JET MOVING THROUGH THE REGION.
SUNDAY AFTERNOON LOOKS TO SEE A NEEDED BREAK IN THE HOLIDAY
WEEKEND ACTIONS WITH THE SUN BREAKING OUT FOR MST OF THE AFTERNOON
AHEAD OF THE NEXT FRONTAL SYSTEM THAT MOVES IN BY EARLY MONDAY
MORNING. THIS SYSTEM IS BOTH MUCH WETTER...WITH MODERATE TO STRONG
SOUTHERLY FLOW LOOKING TO HAVE A SUBTROPICAL FEED CONNECTION. IN
ADDITION TO THE GOOD MOISTURE FLUX INTO THE REGION ADDING A MID
LEVEL MOISTURE FEED TO THE ALREADY STRONG MOISTURE LOW LEVEL FEED
INTO THE REGION. AND ADDING TO THE GOOD LOW LEVEL MOISTURE AND LOW
LEVEL OROGRAPHIC LIFT IN THE STRONG WARM CONVEYOR FLOW...THERE IS
A GOOD UPPER LEVEL DYNAMIC COMPONENT AS THE LEFT EXIT REGION OF A
+100KT JET LINGERS OVER THE AREA FROM MONDAY MORNING THROUGH
TUESDAY MORNING. THIS PROLONGED PERIOD OF GOOD LOW TO HIGH LEVEL
LIFT COUPLING BRINGS AN UNUSUALLY WET PERIOD IN DEEP OMEGA TO CAP
OFF THE HOLIDAY WEEKEND.
&&
.AVIATION...AREAS OF MVFR CIGS ALONG THE COAST COULD LOWER TO IFR
THIS MORNING. INLAND FROM THE CASCADES WESTWARD AND SISKIYOUS
NORTHWARD, EXPECT MVFR CIGS TO DEVELOP IN THE UMPQUA VALLEY AND
ALSO BANK UP AGAINST THE MOUNTAINS RESULTING IN TERRAIN
OBSCURATIONS.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
SBN/SBN/SBN
000
FXUS66 KMFR 250325
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
825 PM PDT FRI MAY 24 2013
.DISCUSSION...NO CHANGES PLANNED FOR THIS EVENING AS NOTHING MUCH
IS GOING ON ACROSS OUR AREA. THE UPPER TROUGH THAT HAS BOTHERED
US FOR DAYS HAS FINALLY OPENED UP AND MUCH OF ITS ENERGY IS
SCOOTING OFF INTO THE NORTHERN ROCKIES. THERE IS A WEAK TROUGH
AXIS/SHORTWAVE PASSING THROUGH RIGHT NOW BUT NONE OF THE OBS SITES
OR CAMS SHOW ANY PRECIPITATION, SO IT`S JUST A MID AND HIGH CLOUD
STORM. AND EVEN THAT IS MOSTLY ON THE EAST SIDE.
THE DEPARTURE OF THE TROUGH OPENS UP THE WEST COAST TO THE MOIST
WESTERLIES ACROSS THE PACIFIC. THIS DOESN`T BODE REAL WELL FOR OUR
WEEKEND, UNFORTUNATELY. THE NEXT SYSTEM CAN BE SEEN AROUND 135W.
IT IS FAIRLY WEAK BUT IT WILL BRING US SOME SHOWERS LATER
TOMORROW. NEVERTHELESS, OF ANY OF THE DAYS THIS THE WEEKEND,
SATURDAY LOOKS THE BEST AREA WIDE. AN UPPER TROUGH AXIS SLIDES
THROUGH SUNDAY WITH RAIN EARLY ON THE WEST SIDE TRANSITIONING
MOSTLY TO THE EAST SIDE BY AFTERNOON. THIS WILL BE FOLLOWED BY A
MUCH WETTER SYSTEM MONDAY. AGREEMENT AMONGST THE MODELS REMAINS
PRETTY HIGH AND THUS IT LOOKS QUITE WET WEST OF THE CASCADES ON
MEMORIAL DAY. EAST SIDE AREAS WILL GET COMPARATIVELY LESS PRECIP,
BUT ALL OF US SHOULD GET WET AT SOME POINT MONDAY. -WRIGHT
&&
.AVIATION...EXPECT WIDESPREAD VFR EAST OF THE CASCADES TONIGHT
INTO SATURDAY WITH A MID-LEVEL DECK IN THE AREA. AREAS OF MVFR
CIGS ALONG THE COAST COULD LOWER TO IFR OVERNIGHT INTO SATURDAY
MORNING. INLAND FROM THE CASCADES WESTWARD AND SISKIYOUS
NORTHWARD, EXPECT VFR THIS EVENING, BUT MVFR CIGS WILL DEVELOP IN
THE UMPQUA VALLEY AND ALSO BANK UP AGAINST THE MOUNTAINS RESULTING
IN TERRAIN OBSCURATIONS. /FB
&&
.PREV DISCUSSION... /ISSUED 128 PM PDT FRI MAY 24 2013/
DISCUSSION...24/12Z NAM/GFS IN.
LOTS OF STRATOCUMULUS PERSIST FROM THE CASCADES WEST AND SISKIYOUS
NORTH THIS AFTERNOON...WITH SCATTERED COVERAGE OVER THE REMAINDER
OF THE AREA.
A LOW OVER WESTERN WASHINGTON STATE...AND THE SHORT WAVES
ROTATING AROUND IT...WILL CONTINUE TO BE THE DOMINANT WEATHER
FEATURE OVER THE PACIFIC NORTHWEST FOR THE NEXT FEW DAYS. THE LOW
ITSELF WILL MOVE INTO ALBERTA TONIGHT...BUT STRONG SHORT WAVES
WILL CONTINUE TO ROLL THROUGH THE PACIFIC NORTHWEST THROUGH
SUNDAY. THEREFORE...EXPECT UNSETTLED SHOWERY WEATHER TO CONTINUE.
THE TWO FACTORS THAT PROMOTE CONVECTION...DIURNAL HEATING AND
SHORT WAVES ALOFT...WILL REINFORCE EACH OTHER SATURDAY AFTERNOON
AND EVENING...AND THAT IS WHEN THE MOST ACTIVITY IS EXPECTED. THE
SHORT WAVE WILL SUPPORT ACTIVITY MOST OF SATURDAY NIGHT. LOOKING
AT MODEL CAPES AND LIFTED INDICES...BOTH PLANER VIEWS AND IN EAST
SIDE SOUNDINGS...SUPPORT FOR DEEP CONVECTION LOOKS MINIMAL. CAPES
ARE GENERALLY LESS THAN 100 J/KG AND LIFTED INDICES ARE NEAR ZERO
SATURDAY AFTERNOON AND EVENING WITH PRECIPITABLE WATER VALUES
AROUND 0.40 INCHES. THE GFS AND NAM SOUNDINGS BOTH SHOW CAPPING
AROUND 600 MB. THE SUNDAY AFTERNOON NAM SOUNDINGS LOOK SIMILAR TO
THOSE FOR SATURDAY. THE GFS LOOKS SLIGHTLY MORE CONVECTIVE SUNDAY
WITH A WEAKER CAP AND A LIFTED INDEX OF -1.8 AT LAKEVIEW...BUT IT
STILL DOESN`T LOOK IMPRESSIVE. THE BOTHWELL LIGHTNING PROGS SHOW
LESS THAN A 10 PERCENT CHANCE OF EVEN ONE LIGHTNING STRIKE OVER
THE AREA. SO...WILL DROP MENTION OF THUNDERSTORMS FOR SATURDAY.
SINCE THE GFS SHOWS SOME SUPPORT FOR THUNDERSTORMS OVER THE FAR
EAST SIDE SUNDAY AFTERNOON/EVENING...WILL RETAIN ISOLATED
THUNDERSTORMS THEN.
THE LAST SHORT WAVE WILL ROLL THROUGH SUNDAY...BUT THE NEXT
UPSTREAM SYSTEM...IN THE FORM OF A WEAK LONG WAVE TROUGH THAT WILL
DIG AS IT MOVES INTO THE WEST COAST...WILL MOVE IN RATHER
QUICKLY. IT WILL PUSH A WET WARM FRONT ONSHORE LATE SUNDAY NIGHT
INTO MONDAY MORNING...AND THE TRAILING COLD FRONT WILL MOVE
ONSHORE MONDAY. THIS LOOKS TO BE A FAIRLY WET SYSTEM WITH MOST OF
THE AREA GETTING WETTING RAINS...THE EXCEPTION BEING PARTS OF THE
EAST SIDE.
FORECAST CONFIDENCE DROPS OFF QUITE A BIT AFTER MONDAY WITH THE
MODELS SHOWING LOTS OF VARIATION...BOTH BETWEEN MODELS AND FROM
RUN TO RUN WITHIN THE SAME MODEL.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY...THE TENDENCY IN THE
EXTENDED IS FOR THE LONG WAVE TROUGH TO PERSIST OVER THE WEST BUT
WITH A GRADUAL RISE IN HEIGHTS. SO, THIS SHOULD KEEP TEMPERATURES
NEAR OR SLIGHTLY BELOW THE SEASONAL AVERAGES, WHICH FOR MEDFORD ARE
IN THE MID 70S FOR HIGHS AND THE UPPER 40S FOR LOWS. A PROGRESSIVE
WESTERLY JET WILL BRING ANOTHER SHORT WAVE INTO THE COAST WEDNESDAY
WITH SHOWERS LIKELY ALONG THE COAST/WEST OF THE CASCADES...WITH
SLIGHT CHANCE TO CHANCE POPS EAST OF THE CASCADES. MODELS SHOWING
THIS SYSTEM AMPLIFYING A BIT WEDNESDAY NIGHT INTO THURSDAY AS IT
MOVES INTO EASTERN WASHINGTON AND OREGON, SO HAVE KEPT POPS HIGHER
TO ACCOUNT FOR THIS. WITH SOME RISE IN HEIGHTS EXPECTED THURSDAY
NIGHT INTO FRIDAY...THERE SHOULD BE A REDUCTION IN SHOWER CHANCES
AREA WIDE ALONG WITH A BIT OF A MODERATION IN TEMPERATURES. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
000
FXUS66 KMFR 242028
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
128 PM PDT FRI MAY 24 2013
.DISCUSSION...24/12Z NAM/GFS IN.
LOTS OF STRATOCUMULUS PERSIST FROM THE CASCADES WEST AND SISKIYOUS
NORTH THIS AFTERNOON...WITH SCATTERED COVERAGE OVER THE REMAINDER
OF THE AREA.
A LOW OVER WESTERN WASHINGTON STATE...AND THE SHORT WAVES
ROTATING AROUND IT...WILL CONTINUE TO BE THE DOMINANT WEATHER
FEATURE OVER THE PACIFIC NORTHWEST FOR THE NEXT FEW DAYS. THE LOW
ITSELF WILL MOVE INTO ALBERTA TONIGHT...BUT STRONG SHORT WAVES
WILL CONTINUE TO ROLL THROUGH THE PACIFIC NORTHWEST THROUGH
SUNDAY. THEREFORE...EXPECT UNSETTLED SHOWERY WEATHER TO CONTINUE.
THE TWO FACTORS THAT PROMOTE CONVECTION...DIURNAL HEATING AND
SHORT WAVES ALOFT...WILL REINFORCE EACH OTHER SATURDAY AFTERNOON
AND EVENING...AND THAT IS WHEN THE MOST ACTIVITY IS EXPECTED. THE
SHORT WAVE WILL SUPPORT ACTIVITY MOST OF SATURDAY NIGHT. LOOKING
AT MODEL CAPES AND LIFTED INDICES...BOTH PLANER VIEWS AND IN EAST
SIDE SOUNDINGS...SUPPORT FOR DEEP CONVECTION LOOKS MINIMAL. CAPES
ARE GENERALLY LESS THAN 100 J/KG AND LIFTED INDICES ARE NEAR ZERO
SATURDAY AFTERNOON AND EVENING WITH PRECIPITABLE WATER VALUES
AROUND 0.40 INCHES. THE GFS AND NAM SOUNDINGS BOTH SHOW CAPPING
AROUND 600 MB. THE SUNDAY AFTERNOON NAM SOUNDINGS LOOK SIMILAR TO
THOSE FOR SATURDAY. THE GFS LOOKS SLIGHTLY MORE CONVECTIVE SUNDAY
WITH A WEAKER CAP AND A LIFTED INDEX OF -1.8 AT LAKEVIEW...BUT IT
STILL DOESN`T LOOK IMPRESSIVE. THE BOTHWELL LIGHTNING PROGS SHOW
LESS THAN A 10 PERCENT CHANCE OF EVEN ONE LIGHTNING STRIKE OVER
THE AREA. SO...WILL DROP MENTION OF THUNDERSTORMS FOR SATURDAY.
SINCE THE GFS SHOWS SOME SUPPORT FOR THUNDERSTORMS OVER THE FAR
EAST SIDE SUNDAY AFTERNOON/EVENING...WILL RETAIN ISOLATED
THUNDERSTORMS THEN.
THE LAST SHORT WAVE WILL ROLL THROUGH SUNDAY...BUT THE NEXT
UPSTREAM SYSTEM...IN THE FORM OF A WEAK LONG WAVE TROUGH THAT WILL
DIG AS IT MOVES INTO THE WEST COAST...WILL MOVE IN RATHER
QUICKLY. IT WILL PUSH A WET WARM FRONT ONSHORE LATE SUNDAY NIGHT
INTO MONDAY MORNING...AND THE TRAILING COLD FRONT WILL MOVE
ONSHORE MONDAY. THIS LOOKS TO BE A FAIRLY WET SYSTEM WITH MOST OF
THE AREA GETTING WETTING RAINS...THE EXCEPTION BEING PARTS OF THE
EAST SIDE.
FORECAST CONFIDENCE DROPS OFF QUITE A BIT AFTER MONDAY WITH THE
MODELS SHOWING LOTS OF VARIATION...BOTH BETWEEN MODELS AND FROM
RUN TO RUN WITHIN THE SAME MODEL.
.LONG TERM...TUESDAY NIGHT THROUGH FRIDAY...THE TENDENCY IN THE
EXTENDED IS FOR THE LONG WAVE TROUGH TO PERSIST OVER THE WEST BUT
WITH A GRADUAL RISE IN HEIGHTS. SO, THIS SHOULD KEEP TEMPERATURES
NEAR OR SLIGHTLY BELOW THE SEASONAL AVERAGES, WHICH FOR MEDFORD ARE
IN THE MID 70S FOR HIGHS AND THE UPPER 40S FOR LOWS. A PROGRESSIVE
WESTERLY JET WILL BRING ANOTHER SHORT WAVE INTO THE COAST WEDNESDAY
WITH SHOWERS LIKELY ALONG THE COAST/WEST OF THE CASCADES...WITH
SLIGHT CHANCE TO CHANCE POPS EAST OF THE CASCADES. MODELS SHOWING
THIS SYSTEM AMPLIFYING A BIT WEDNESDAY NIGHT INTO THURSDAY AS IT
MOVES INTO EASTERN WASHINGTON AND OREGON, SO HAVE KEPT POPS HIGHER
TO ACCOUNT FOR THIS. WITH SOME RISE IN HEIGHTS EXPECTED THURSDAY
NIGHT INTO FRIDAY...THERE SHOULD BE A REDUCTION IN SHOWER CHANCES
AREA WIDE ALONG WITH A BIT OF A MODERATION IN TEMPERATURES. SPILDE
&&
.AVIATION...BASED ON THE 24/18Z TAF CYCLE.
EXPECT WIDESPREAD VFR EAST OF THE CASCADES TONIGHT INTO SATURDAY
WITH A MID-LEVEL DECK IN THE AREA THIS EVENING. AREAS OF MVFR CIGS
ALONG THE COAST COULD LOWER TO IFR OVERNIGHT INTO SATURDAY MORNING.
INLAND FROM THE CASCADES WESTWARD AND SISKIYOUS NORTHWARD, EXPECT
VFR THIS EVENING, BUT MVFR CIGS WILL DEVELOP IN THE UMPQUA VALLEY
AND ALSO BANK UP AGAINST THE MOUNTAINS RESULTING IN TERRAIN
OBSCURATIONS. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
15/18/8
000
FXUS66 KMFR 241615
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
915 AM PDT FRI MAY 24 2013
.DISCUSSION...24/12Z NAM IN.
LOTS OF STRATOCUMULUS FROM THE CASCADES WEST THIS MORNING...WITH
MORE SCATTERED COVERAGE EAST OF THE CASCADES. THE UPPER LOW
CONTINUES TO SWIRL OVER NORTHEAST OREGON.
THAT LOW...AND SHORT WAVES ROTATING AROUND IT...WILL CONTINUE TO
BE THE DOMINANT WEATHER FEATURE OVER THE PACIFIC NORTHWEST FOR THE
NEXT FEW DAYS. THE LOW ITSELF WILL MOVE INTO ALBERTA TONIGHT...BUT
STRONG SHORT WAVES WILL CONTINUE TO ROLL THROUGH THE PACIFIC
NORTHWEST THROUGH SUNDAY. THEREFORE...EXPECT UNSETTLED SHOWERY
WEATHER TO CONTINUE. THE TWO FACTORS THAT PROMOTE
CONVECTION...DIURNAL HEATING AND SHORT WAVES ALOFT...WILL
REINFORCE EACH OTHER SATURDAY AFTERNOON AND EVENING...AND THAT IS
WHEN THE MOST ACTIVITY IS EXPECTED. THE SHORT WAVE WILL SUPPORT
ACTIVITY MOST OF SATURDAY NIGHT. AT THIS TIME...LITTLE OR NO
THUNDER IS EXPECTED...BUT WILL INVESTIGATE THOSE POSSIBILITIES
FURTHER THIS SHIFT.
THE LAST SHORT WAVE WILL ROLL THROUGH SUNDAY...BUT THE NEXT
UPSTREAM SYSTEM...IN THE FORM OF A WEAK LONG WAVE TROUGH THAT WILL
DIG AS IT MOVES INTO THE WEST COAST...WILL MOVE IN RATHER
QUICKLY. IT WILL PUSH A WET WARM FRONT ONSHORE LATE SUNDAY NIGHT
INTO MONDAY MORNING...AND THE TRAILING COLD FRONT WILL MOVE
ONSHORE MONDAY. THIS LOOKS TO BE A FAIRLY WET SYSTEM WITH MOST OF
THE AREA GETTING WETTING RAINS...THE EXCEPTION BEING PARTS OF THE
EAST SIDE.
FORECAST CONFIDENCE DROPS OFF QUITE A BIT AFTER MONDAY WITH THE
MODELS SHOWING LOTS OF VARIATION...BOTH BETWEEN MODELS AND FROM
RUN TO RUN WITHIN THE SAME MODEL. THE 24/06Z GFS SHOWS WEAK TO
MODERATE ZONAL FLOW WILL REMAIN IN PLACE WEDNESDAY THROUGH FRIDAY.
WEAK EMBEDDED SHORT WAVES WILL MOVE ONSHORE DURING THAT TIME FRAME
WITH MOST OF THE ENERGY FOCUSED NORTH OF THE MEDFORD CWA...BUT
THIS AREA WILL CATCH THE SOUTHERN END OF THE WEAK FRONTS...SO THE
NORTH COAST AND UMPQUA BASIN MAY SEE SOME OCCASIONAL LIGHT
PRECIPITATION. THE 24/00Z EC SHOWS A MORE AMPLIFIED BUT
PROGRESSIVE PATTERN...SO IT BRINGS SLIGHTLY WETTER SYSTEMS TO THE
AREA WITH MORE PRONOUNCED BREAKS IN BETWEEN...BUT IT ISN`T VERY
DIFFERENT FROM THE GFS SOLUTION. GIVEN THE UNCERTAINTY...WON`T TRY
TO NAIL DOWN TIMING AT THIS TIME AND WILL LIKELY GO WITH A BIT
HIGHER THAN CLIMO POPS TUESDAY THROUGH FRIDAY. WON`T DECIDE UNTIL
THE REST OF THE 12Z SUITE COMES IN ALONG WITH THE ENSEMBLES AND
OTHER UNCERTAINTY TOOLS.
&&
.AVIATION...BASED ON THE 24/12Z TAF CYCLE.
MOSTLY VFR CLOUD DECK IS FILLING IN THE WEST SIDE AND COASTAL WATERS
WITH HIGHER TERRAIN OBSCURATIONS. THIS DECK WILL SLOWLY BURN OFF
FROM SOUTH TO NORTH WITH THE UMPQUA BASIN BEING THE LAST TO GO
SCATTERED EARLY TO MID AFTERNOON. AS LOW LEVEL FLOW BECOMES
NORTHWESTERLY LATER THIS AFTERNOON ACROSS THE REGION EXPECT THIS
VFR WITH ISOLATED MVFR DECK WITH HIGHER TERRAIN OBSCURATIONS TO
RETURN LATE THIS EVENING TO THE WEST SIDE. -SVEN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
UNTIL 11 AM PDT THIS MORNING FOR PZZ370-376.
$$
15/15/15
000
FXUS66 KMFR 240930
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
230 AM PDT FRI MAY 24 2013
.DISCUSSION...THE UPPER LOW THAT HAS HOVERED NEAR THE FORECAST AREA
THE LAST FEW DAYS WILL FINALLY LIFT NORTHEAST INTO WASHINGTON STATE
AND WEAKEN. THIS WILL RESULT IN DECREASING SHOWERS FROM SOUTH TO
NORTH...MILDER TEMPERATURES AND DECREASING CLOUD COVER. IN FACT THE
AFTERNOON SHOULD TURN OUT PRETTY NICE WITH PARTLY CLOUDY SKIES AND
TEMPERATURES NEAR NORMAL IN THE ROGUE VALLEY. DRY WEATHER CONTINUES
TONIGHT WITH WEAK TROFING OVER THE AREA.
MODELS SHOW A STRONGER SHORTWAVE TROF MOVING SOUTH INTO WESTERN
OREGON SATURDAY MORNING AND WE`LL SEE SHOWERS STARTING TO DEVELOP
NORTH OF THE UMPQUA DIVIDE IN THE MORNING...THEN SHOWERS ARE
EXPECTED TO DEVELOP ELSEWHERE IN THE AFTERNOON AS THE UPPER TROF
SWINGS SOUTHEAST. MODELS SUGGEST THERE MAY BE ENOUGH INSTABILITY FOR
ISOLATED THUNDERSTORMS EAST OF THE CASCADES SATURDAY AFTERNOON AND
EVENING.
AN UPPER LOW MOVES INTO THE FORECAST AREA SUNDAY AND THIS IS
EXPECTED TO BRING MORE WIDESPREAD SHOWERS. THE EASTSIDE WILL HAVE A
SLIGHT CHANCE OF THUNDERSTORMS SUNDAY AFTERNOON AND EVENING.
THE UPPER LOW LIFT NORTHEAST SUNDAY NIGHT AND ANY DRY BREAKS WILL BE
BRIEF. THE MODELS ARE IN FAIRLY GOOD AGREEMENT SHOWING A STRONGER
FRONTAL BOUNDARY BRINGING THE POTENTIAL FOR STEADY RAIN TO THE COAST
MID TO LATE MONDAY MORNING...THEN SPREADING INLAND MONDAY AFTERNOON
SO IT SHOULD NOT BE A TOTAL WASH OUT -PETRUCELLI
&&
.AVIATION...
BASED ON THE 24/06Z TAF CYCLE.
DEEP MOISTURE CONTINUES TO STREAM IN ACROSS THE NORTH COAST INTO THE
NORTH CASCADES AROUND CRATER LAKE. THIS WILL LEAD TO AREAS OF RAIN
WITH MVFR CIGS AND MOUNTAIN OBSCURATIONS OVER NORTHERN
AREAS...ROUGHLY NORTH OF THE UMPQUA DIVIDE. WE MAY SEE A FEW SHOWERS
IN THE ROGUE VALLEY EARLY THIS MORNING WITH OCCASIONAL MVFR CIGS,
BUT MOST OF THE PRECIPITATION WILL REMAIN NORTH OF US. THE EAST
SIDE AND NORCAL WILL REMAIN VFR THROUGH TODAY WITH HIGH CLOUD OVER
ERN OREGON AND MOSTLY CLEAR SKIES IN NORCAL. -WRIGHT
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
11 AM PDT THIS MORNING FOR PZZ370-376.
$$
000
FXUS66 KMFR 240328
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
828 PM PDT THU MAY 23 2013
.DISCUSSION...NO UPDATES PLANNED THIS EVENING. A STEADY STREAM OF
MOISTURE REMAINS AIMED AT THE NORTH COAST AND UMPQUA AREAS THIS
EVENING. WHILE WEBCAMS GENERALLY SHOW DRY ROADS AND MANY AREA OBS
HAVEN`T RECORDED RAIN IN A WHILE, THERE IS ANOTHER PLUME OF DEEPER
MOISTURE MOVING SOUTH ALONG THE COAST, SO RAIN OUGHT TO START UP
OVER THESE AREAS THIS EVENING AND CONTINUE TONIGHT. THE REST OF
US ARE CURRENTLY DRY AND WILL LIKELY ONLY BE DODGING SCATTERED
SHOWERS TONIGHT. THE CURRENT FORECAST COVERS THIS WELL. -WRIGHT
&&
.AVIATION...LOW PRESSURE TO THE NORTH WILL CONTINUE TO BRING SOME
LIGHT RAIN ALONG WITH A MIX OF VFR AND MVFR NORTH OF THE UMPQUA
DIVIDE AND ALONG THE NORTH COAST THROUGH TONIGHT. MOSTLY VFR IS
EXPECTED SOUTH OF THE UMPQUA DIVIDE THROUGH TONIGHT, BUT CANNOT
RULE OUT SOME MVFR IN ISOLATED AREAS OVERNIGHT...THEN AGAIN TOWARD
SUNRISE OVER THE VALLEYS. PARTIAL MOUNTAIN OBSCURATION IS ALSO
LIKELY, ESPECIALLY ACROSS THE NORTHERN HALF OF THE CWA. EAST OF
THE CASCADES...SOME SCATTERED SHOWERS COULD RESULT IN BRIEF
PERIODS OF MVFR THROUGH TONIGHT. OTHERWISE...VFR WILL PREVAIL.
-BPN
&&
.PREV DISCUSSION... /ISSUED 235 PM PDT THU MAY 23 2013/
SHORT TERM...THE UPPER LOW REMAINS OVER THE REGION TODAY AND
TONIGHT. AS THE CENTER OF THE LOW SWINGS SOUTHWARD ALONG THE
COAST TODAY THEN INLAND THIS EVENING AND TONIGHT EXPECT ADDITIONAL
SHOWERS TO MOVE INTO THE AREA. ON FRIDAY THE LOW CENTER WILL SHIFT
NORTHEAST THEN A BROAD TROUGH REMAINS OVER THE REGION ON SATURDAY
AND SUNDAY. EMBEDDED WITH THE TROUGH...ANOTHER SHORTWAVE IS
FORECAST TO MOVE TOWARDS THE COAST SATURDAY AND INLAND SATURDAY
NIGHT AND SUNDAY. THIS WILL BRING ADDITIONAL SHOWERS SATURDAY WITH
INCREASING SHOWER ACTIVITY ON SUNDAY. ALSO DURING THE AFTERNOON
AND EVENING TODAY AND AGAIN ON SATURDAY AND SUNDAY THERE IS A
SLIGHT CHANCE FOR THUNDERSTORMS FOR LOCATION EAST OF THE CASCADES.
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS HAVE DEVELOP EAST OF
THE CASCADES THIS AFTERNOON WHILE FROM THE CASCADES WEST...SHOWERS
ARE EXPECTED TO DEVELOP LATE THIS AFTERNOON INTO THIS EVENING AS
THE UPPER LOW CENTER MOVES INTO CENTRAL OREGON. THE BEST CHANCES
FOR SHOWER ACTIVITY WILL BE OVER COOS AND DOUGLAS COUNTIES AS WELL
AS INTO THE SOUTHERN OREGON CASCADES WITH ISOLATED TO SCATTERED
SHOWERS IN OTHER AREAS OF THE CWA. ALSO OF NOTE IS THAT ANOTHER
COOL NIGHT IS EXPECTED EAST OF THE CASCADES TONIGHT INTO EARLY
FRIDAY MORNING WITH LOW TEMPERATURES EXPECTED NEAR OR JUST ABOVE
FREEZING. IN THE KLAMATH BASIN...DO NOT EXPECT WIDESPREAD FREEZING
CONDITIONS TONIGHT AND AREAS THAT REACH FREEZING MAY JUST BRIEFLY
DIP INTO THE LOW 30S SO HAVE NOT ISSUED A FREEZE WARNING FOR THIS
AREA.
AS THE LOW CENTER TRACKS TO THE NORTHEAST ON FRIDAY EXPECT
DECREASING SHOWERS ACROSS THE AREA BY AFTERNOON. MODELS CONTINUE TO
INDICATE A BROAD TROUGH WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. THIS IS EXPECTED TO BRING MILD TEMPERATURES WITH HIGHS
NEAR OR JUST BELOW NORMAL. CHANCES FOR SHOWERS WILL CONTINUE AS
WELL ON THE WEEKEND. ANOTHER SHORTWAVE IS FORECAST TO MOVE TOWARDS
THE AREA SATURDAY THEN INLAND SUNDAY. AHEAD OF THE SHORTWAVE
EXPECT SOME SCATTERED SHOWERS TO DEVELOP SATURDAY AFTERNOON AND
EVENING. A SLIGHT CHANCE OF THUNDERSTORMS IS ALSO
POSSIBLE...MAINLY EAST OF THE CASCADES ON SATURDAY. BY SUNDAY
MODELS INDICATE CONTINUED MOISTURE AND INCREASING INSTABILITY.
EXPECT MOST AREAS TO SEE A CHANCE FOR SHOWERS SUNDAY WITH
THUNDERSTORMS POSSIBLE IN THE AFTERNOON AND EVENING FROM THE
CASCADES EAST.
LONG TERM...MEMORIAL DAY THROUGH THURSDAY...CONFIDENCE REMAINS HIGH
IN THE OVERALL WEATHER PATTERN IN THE EXTENDED AS GEFS/ECMWF
ENSEMBLE MEANS BOTH FOCUS A TROUGH OVER THE WESTERN UNITED STATES
WITH BELOW NORMAL HEIGHTS. WHILE IT WON`T BE AS COOL AS IT WAS
EARLIER THIS WEEK, TEMPERATURES OVERALL FOR THE PERIOD WILL LIKELY
REMAIN SLIGHTLY BELOW NORMAL. THAT TRANSLATES TO UPPER 60S AND LOWER
70S FOR HIGHS IN MEDFORD. TIMING AND STRENGTH DETAILS OF INDIVIDUAL
SHORT WAVES MOVING INTO THE NORTHWEST WILL BE DIFFICULT, BUT THE
STRONGEST IS LIKELY TO ARRIVE AT THE COAST MONDAY MORNING, THEN PUSH
INLAND DURING THE AFTERNOON/EVENING. THE 00Z DETERMINISTIC RUN OF
THE ECMWF WAS WEAKER AND FARTHER SOUTH WITH THIS FEATURE, BUT THE
12Z RUN HAS COME MORE IN LINE WITH THE 12Z GFS (THOUGH STILL IS A
BIT WEAKER AND FARTHER SOUTH). EVEN SO, FELT CONFIDENT ENOUGH HERE
TO INCREASE POPS DURING THIS TIME, SINCE THAT IS WHERE THE FOCUS OF
PRECIP LIKELY WILL BE. HEIGHTS WILL RISE A BIT TUESDAY, BUT REMAIN
BELOW NORMAL, SO HAVE MAINTAINED SLIGHT CHC TO CHC POPS. MODELS
SHOWING ANOTHER SHORT WAVE APPROACHING THE COAST WEDNESDAY INTO
THURSDAY IN THE MOIST WESTERLY ONSHORE FLOW. THIS SHOULD KEEP THE
PROBABILITY OF SHOWERS HIGHEST ALONG AND WEST OF THE CASCADES.
BEYOND THAT, THE GFS ENSEMBLES CARVE ANOTHER DEEP TROUGH/CLOSED LOW
OVER THE AREA/JUST OFFSHORE NEXT WEEKEND, WHILE THE ECMWF IS FLATTER
AND MORE ZONAL. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
5 AM PDT FRIDAY FOR PZZ370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM PDT FRIDAY
FOR PZZ350.
$$
000
FXUS66 KMFR 232135
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
235 PM PDT THU MAY 23 2013
.SHORT TERM...THE UPPER LOW REMAINS OVER THE REGION TODAY AND
TONIGHT. AS THE CENTER OF THE LOW SWINGS SOUTHWARD ALONG THE
COAST TODAY THEN INLAND THIS EVENING AND TONIGHT EXPECT ADDITIONAL
SHOWERS TO MOVE INTO THE AREA. ON FRIDAY THE LOW CENTER WILL SHIFT
NORTHEAST THEN A BROAD TROUGH REMAINS OVER THE REGION ON SATURDAY
AND SUNDAY. EMBEDDED WITH THE TROUGH...ANOTHER SHORTWAVE IS
FORECAST TO MOVE TOWARDS THE COAST SATURDAY AND INLAND SATURDAY
NIGHT AND SUNDAY. THIS WILL BRING ADDITIONAL SHOWERS SATURDAY WITH
INCREASING SHOWER ACTIVITY ON SUNDAY. ALSO DURING THE AFTERNOON
AND EVENING TODAY AND AGAIN ON SATURDAY AND SUNDAY THERE IS A
SLIGHT CHANCE FOR THUNDERSTORMS FOR LOCATION EAST OF THE CASCADES.
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS HAVE DEVELOP EAST OF
THE CASCADES THIS AFTERNOON WHILE FROM THE CASCADES WEST...SHOWERS
ARE EXPECTED TO DEVELOP LATE THIS AFTERNOON INTO THIS EVENING AS
THE UPPER LOW CENTER MOVES INTO CENTRAL OREGON. THE BEST CHANCES
FOR SHOWER ACTIVITY WILL BE OVER COOS AND DOUGLAS COUNTIES AS WELL
AS INTO THE SOUTHERN OREGON CASCADES WITH ISOLATED TO SCATTERED
SHOWERS IN OTHER AREAS OF THE CWA. ALSO OF NOTE IS THAT ANOTHER
COOL NIGHT IS EXPECTED EAST OF THE CASCADES TONIGHT INTO EARLY
FRIDAY MORNING WITH LOW TEMPERATURES EXPECTED NEAR OR JUST ABOVE
FREEZING. IN THE KLAMATH BASIN...DO NOT EXPECT WIDESPREAD FREEZING
CONDITIONS TONIGHT AND AREAS THAT REACH FREEZING MAY JUST BRIEFLY
DIP INTO THE LOW 30S SO HAVE NOT ISSUED A FREEZE WARNING FOR THIS
AREA.
AS THE LOW CENTER TRACKS TO THE NORTHEAST ON FRIDAY EXPECT
DECREASING SHOWERS ACROSS THE AREA BY AFTERNOON. MODELS CONTINUE TO
INDICATE A BROAD TROUGH WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. THIS IS EXPECTED TO BRING MILD TEMPERATURES WITH HIGHS
NEAR OR JUST BELOW NORMAL. CHANCES FOR SHOWERS WILL CONTINUE AS
WELL ON THE WEEKEND. ANOTHER SHORTWAVE IS FORECAST TO MOVE TOWARDS
THE AREA SATURDAY THEN INLAND SUNDAY. AHEAD OF THE SHORTWAVE
EXPECT SOME SCATTERED SHOWERS TO DEVELOP SATURDAY AFTERNOON AND
EVENING. A SLIGHT CHANCE OF THUNDERSTORMS IS ALSO
POSSIBLE...MAINLY EAST OF THE CASCADES ON SATURDAY. BY SUNDAY
MODELS INDICATE CONTINUED MOISTURE AND INCREASING INSTABILITY.
EXPECT MOST AREAS TO SEE A CHANCE FOR SHOWERS SUNDAY WITH
THUNDERSTORMS POSSIBLE IN THE AFTERNOON AND EVENING FROM THE
CASCADES EAST.
.LONG TERM...MEMORIAL DAY THROUGH THURSDAY...CONFIDENCE REMAINS HIGH
IN THE OVERALL WEATHER PATTERN IN THE EXTENDED AS GEFS/ECMWF
ENSEMBLE MEANS BOTH FOCUS A TROUGH OVER THE WESTERN UNITED STATES
WITH BELOW NORMAL HEIGHTS. WHILE IT WON`T BE AS COOL AS IT WAS
EARLIER THIS WEEK, TEMPERATURES OVERALL FOR THE PERIOD WILL LIKELY
REMAIN SLIGHTLY BELOW NORMAL. THAT TRANSLATES TO UPPER 60S AND LOWER
70S FOR HIGHS IN MEDFORD. TIMING AND STRENGTH DETAILS OF INDIVIDUAL
SHORT WAVES MOVING INTO THE NORTHWEST WILL BE DIFFICULT, BUT THE
STRONGEST IS LIKELY TO ARRIVE AT THE COAST MONDAY MORNING, THEN PUSH
INLAND DURING THE AFTERNOON/EVENING. THE 00Z DETERMINISTIC RUN OF
THE ECMWF WAS WEAKER AND FARTHER SOUTH WITH THIS FEATURE, BUT THE
12Z RUN HAS COME MORE IN LINE WITH THE 12Z GFS (THOUGH STILL IS A
BIT WEAKER AND FARTHER SOUTH). EVEN SO, FELT CONFIDENT ENOUGH HERE
TO INCREASE POPS DURING THIS TIME, SINCE THAT IS WHERE THE FOCUS OF
PRECIP LIKELY WILL BE. HEIGHTS WILL RISE A BIT TUESDAY, BUT REMAIN
BELOW NORMAL, SO HAVE MAINTAINED SLIGHT CHC TO CHC POPS. MODELS
SHOWING ANOTHER SHORT WAVE APPROACHING THE COAST WEDNESDAY INTO
THURSDAY IN THE MOIST WESTERLY ONSHORE FLOW. THIS SHOULD KEEP THE
PROBABILITY OF SHOWERS HIGHEST ALONG AND WEST OF THE CASCADES.
BEYOND THAT, THE GFS ENSEMBLES CARVE ANOTHER DEEP TROUGH/CLOSED LOW
OVER THE AREA/JUST OFFSHORE NEXT WEEKEND, WHILE THE ECMWF IS FLATTER
AND MORE ZONAL. SPILDE
&&
.AVIATION...LOW PRESSURE TO THE NORTH WILL CONTINUE TO BRING SOME
LIGHT RAIN ALONG WITH A MIX OF VFR AND MVFR NORTH OF THE UMPQUA
DIVIDE AND ALONG THE NORTH COAST THE REST OF THIS AFTERNOON
THROUGH TONIGHT. MOSTLY VFR IS EXPECTED SOUTH OF THE UMPQUA DIVIDE
THROUGH TONIGHT, BUT WE CANNOT RULE OUT SOME MVFR IN ISOLATED
HEAVIER SHOWERS THIS AFTERNOON, THEN AGAIN TOWARD SUNRISE OVER THE
VALLEYS. PARTIAL MOUNTAIN OBSCURATION IS ALSO LIKELY, ESPECIALLY
ACROSS THE NORTHERN HALF OF THE CWA. EAST OF THE CASCADES,
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OCCURRING THIS
AFTERNOON...MOST NUMEROUS ALONG AND EAST OF WINTER RIM SOUTHWARD
TO THE WARNERS. SOME MVFR CIGS ARE LIKELY IN THE HEAVIER SHOWERS,
BUT THESE WILL TEND TO DIMINISH AFTER SUNSET WITH VFR PREVAILING
ONCE AGAIN. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT FRIDAY
FOR PZZ370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM PDT FRIDAY
FOR PZZ350.
$$
CC
000
FXUS66 KMFR 231556
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
856 AM PDT THU MAY 23 2013
.SHORT TERM...THE UPPER LOW REMAINS OVER THE AREA TODAY. A
SHORTWAVE IS BRINGING SCATTERED SHOWERS EAST OF THE CASCADES WHILE
CONTINUED ONSHORE MOISTURE IS BRINGING ISOLATED SHOWERS TO WEST
SIDE LOCATIONS. A VORT MAX ASSOCIATED WITH UPPER LOW SHIFTS
SOUTH AND INTO THE SOUTHERN OREGON COAST BY LATE THIS AFTERNOON
INTO THE EVENING. SHOWERS ARE EXPECTED TO INCREASE DURING THE
AFTERNOON FOR AREAS FROM THE SOUTHERN OREGON CASCADES WEST...WITH
GREATEST SHOWERS ACROSS COOS AND DOUGLAS COUNTY AREAS. MODELS ARE
TRACKING THIS FEATURE INLAND OVER NORTHERN PORTIONS OF THE CWA
THIS EVENING AND TONIGHT. SOME MODERATE RAIN IS POSSIBLE AS THIS
DISTURBANCE MOVES INLAND ESPECIALLY IS THE COOS AND DOUGLAS AREAS.
ALSO MODELS CONTINUE TO SHOW WEAK INSTABILITY OVER PORTIONS OF THE
EAST SIDE MAINLY IN LAKE COUNTY...SO HAVE CONTINUED THE MENTION
THAT ISOLATED THUNDERSTORMS ARE POSSIBLE OVER THIS AREA THIS
AFTERNOON AND EVENING.
DURING THE DAY FRIDAY EXPECT DECREASING SHOWERS AS THE CORE OF THE
UPPER FINALLY MOVES NORTHEAST. WE WILL STILL HAVE A BROAD TROUGH
OVER THE REGION THOUGH BRINGING MILD TEMPERATURES WITH HIGHS
EXPECTED NEAR NORMAL. ANOTHER DISTURBANCE IS FORECAST TO MOVE
INLAND SATURDAY WITH ANOTHER ROUND OF SCATTERED SHOWERS POSSIBLE
SATURDAY AFTERNOON AND EVENING. A SLIGHT CHANCE OF THUNDERSTORMS
EAST OF THE CASCADES IS ALSO POSSIBLE SATURDAY.
&&
.AVIATION...MOISTURE WILL CONTINUE TO BRING SCATTERED SHOWERS TO
THE COAST AND INLAND TO THE SOUTHERN OREGON CASCADES WITH AREAS OF
MVFR CIGS THIS MORNING...INCLUDING AT KMFR...BECOMING MAINLY VFR
BY LATE MORNING. MOUNTAIN OBSCURATION WILL BE FAIRLY WIDESPREAD
TODAY. TO THE EAST OF THE CASCADES LIGHT RAIN AND SNOW SHOWERS
WILL BRING AREAS OF MVFR CIGS THIS MORNING BUT CONDITIONS WILL
IMPROVE TO MAINLY VFR IN THE LATE MORNING...INCLUDING AT KLMT. BY
LATE THIS AFTERNOON ANOTHER DISTURBANCE WILL FIRE OFF MORE SHOWERS
LEADING TO AREAS OF MVFR CIGS ACROSS THE FORECAST AREA. /FB
&&
.PREV DISCUSSION... /ISSUED 313 AM PDT THU MAY 23 2013/
DISCUSSION...CURRENT WATER VAPOR IMAGE SHOWS THE UPPER LOW SPINNING
NEAR THE OREGON/WASHINGTON BORDER AND THIS IS EXPECTED TO CONTINUE
THROUGH FRIDAY MORNING BEFORE WEAKENING AND LIFTING NORTHEAST INTO
WASHINGTON STATE FRIDAY AFTERNOON. A WEAK UPPER TROF REMAINS OVER
THE FORECAST AREA FRIDAY NIGHT THROUGH SATURDAY.
PRECIPITATION HAS DECREASED AND ENDED DURING THE OVERNIGHT HOURS.
HOWEVER EXPECT SHOWERS TO INCREASE AGAIN LATE WITH A SERIES OF
SHORTWAVES ROTATING AROUND THE UPPER LOW. MOST OF THE SHOWERS SHOULD
BE CONCENTRATED ALONG AND WEST OF THE CASCADES AND NORTHERN KLAMATH
AND LAKE COUNTIES AND MORE ISOLATED IN NORTHERN CAL. THERE MAY BE
ENOUGH INSTABILITY FOR ISOLATED THUNDERSTORMS EAST OF THE CASCADES
IN THE AFTERNOON...BUT THIS WILL BE THE EXCEPTION. MOST HOURS AND
LOCATIONS WILL HAVE JUST INSTABILITY SHOWERS.
ANOTHER SHORTWAVE ROTATING AROUND THE UPPER LOW IS EXPECTED TO MOVE
INTO THE NORTHWEST PART OF THE FORECAST AREA TONIGHT RESULTING IN A
CONTINUATION OF SHOWERS MAINLY NORTH OF THE UMPQUA DIVIDE AND
CASCADES NEAR AND NORTH OF CRATER LAKE. ELSEWHERE SHOWERS ARE
EXPECTED TO BE MORE ISOLATED. PLENTY OF CLOUD COVER REMAINS OVER THE
AREA WHICH WILL LIMIT THE AMOUNT OF COOLING AT NIGHT. NOT AS
CONFIDENT WE`LL GET A SUSTAINED PERIOD OF FREEZING TEMPERATURES IN
THE KLAMATH BASIN AND SHASTA VALLEY.
THE UPPER LOW WILL MOVE NORTHEAST INTO WASHINGTON STATE FRIDAY AND
AS IT DOES SHOWERS WILL DECREASE FROM SOUTH TO NORTH WITH MOST
EXITING THE FORECAST AREA BY FRIDAY EVENING. WE`LL CATCH A BREAK IN
SHOWER ACTIVITY FRIDAY NIGHT.
ANOTHER...BUT WEAKER UPPER TROF SWINGS INTO THE AREA SATURDAY
MORNING WITH SHOWERS EXPECTED TO INCREASE WEST OF THE CASCADES. THE
NAM SHOWS QPF BREAKING OUT EAST OF THE CASCADES IN THE AFTERNOON
WHICH IS MOST LIKELY A RESULT OF INCREASING INSTABILITY AND WEAK
SHORTWAVES PASSING BY.
WEAK TROFING REMAINS OVER THE AREA SUNDAY. HOWEVER THE GFS SUGGEST
THE TROF AXIS WILL MOVE EAST IN THE AFTERNOON WITH WEAK RIDGING
BUILDING FROM THE WEST. CONFIDENCE IS NOT HIGH ON THE GFS SOLUTION
THEREFORE WE`LL KEEP THE CHANCE OF SHOWERS IN THROUGHOUT THE DAY.
-PETRUCELLI
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT THIS
MORNING FOR PZZ356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350.
$$
CC
000
FXUS66 KMFR 231013
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
313 AM PDT THU MAY 23 2013
.DISCUSSION...CURRENT WATER VAPOR IMAGE SHOWS THE UPPER LOW SPINNING
NEAR THE OREGON/WASHINGTON BORDER AND THIS IS EXPECTED TO CONTINUE
THROUGH FRIDAY MORNING BEFORE WEAKENING AND LIFTING NORTHEAST INTO
WASHINGTON STATE FRIDAY AFTERNOON. A WEAK UPPER TROF REMAINS OVER
THE FORECAST AREA FRIDAY NIGHT THROUGH SATURDAY.
PRECIPITATION HAS DECREASED AND ENDED DURING THE OVERNIGHT HOURS.
HOWEVER EXPECT SHOWERS TO INCREASE AGAIN LATE WITH A SERIES OF
SHORTWAVES ROTATING AROUND THE UPPER LOW. MOST OF THE SHOWERS SHOULD
BE CONCENTRATED ALONG AND WEST OF THE CASCADES AND NORTHERN KLAMATH
AND LAKE COUNTIES AND MORE ISOLATED IN NORTHERN CAL. THERE MAY BE
ENOUGH INSTABILITY FOR ISOLATED THUNDERSTORMS EAST OF THE CASCADES
IN THE AFTERNOON...BUT THIS WILL BE THE EXCEPTION. MOST HOURS AND
LOCATIONS WILL HAVE JUST INSTABILITY SHOWERS.
ANOTHER SHORTWAVE ROTATING AROUND THE UPPER LOW IS EXPECTED TO MOVE
INTO THE NORTHWEST PART OF THE FORECAST AREA TONIGHT RESULTING IN A
CONTINUATION OF SHOWERS MAINLY NORTH OF THE UMPQUA DIVIDE AND
CASCADES NEAR AND NORTH OF CRATER LAKE. ELSEWHERE SHOWERS ARE
EXPECTED TO BE MORE ISOLATED. PLENTY OF CLOUD COVER REMAINS OVER THE
AREA WHICH WILL LIMIT THE AMOUNT OF COOLING AT NIGHT. NOT AS
CONFIDENT WE`LL GET A SUSTAINED PERIOD OF FREEZING TEMPERATURES IN
THE KLAMATH BASIN AND SHASTA VALLEY.
THE UPPER LOW WILL MOVE NORTHEAST INTO WASHINGTON STATE FRIDAY AND
AS IT DOES SHOWERS WILL DECREASE FROM SOUTH TO NORTH WITH MOST
EXITING THE FORECAST AREA BY FRIDAY EVENING. WE`LL CATCH A BREAK IN
SHOWER ACTIVITY FRIDAY NIGHT.
ANOTHER...BUT WEAKER UPPER TROF SWINGS INTO THE AREA SATURDAY
MORNING WITH SHOWERS EXPECTED TO INCREASE WEST OF THE CASCADES. THE
NAM SHOWS QPF BREAKING OUT EAST OF THE CASCADES IN THE AFTERNOON
WHICH IS MOST LIKELY A RESULT OF INCREASING INSTABILITY AND WEAK
SHORTWAVES PASSING BY.
WEAK TROFING REMAINS OVER THE AREA SUNDAY. HOWEVER THE GFS SUGGEST
THE TROF AXIS WILL MOVE EAST IN THE AFTERNOON WITH WEAK RIDGING
BUILDING FROM THE WEST. CONFIDENCE IS NOT HIGH ON THE GFS SOLUTION
THEREFORE WE`LL KEEP THE CHANCE OF SHOWERS IN THROUGHOUT THE DAY.
-PETRUCELLI
&&
.AVIATION...
BASED ON THE 23/06Z TAF CYCLE.
A PERSISTENT STREAM OF MOISTURE WILL CONTINUE TO MOVE INTO THE NORTH
COAST, UMPQUA, AND NORTH CASCADES THIS MORNING. THIS WILL KEEP
LIGHT RAIN GOING ALONG THE COAST WITH SCATTERED TO NUMEROUS
SHOWERS INLAND TO THE CASCADES WITH MVFR CIGS AND OCCASIONAL MVFR
VIS OVER THIS AREA. MOUNTAIN OBSCURATION WILL ALSO BE FAIRLY
WIDESPREAD ON THE WEST SIDE. SHOWERS WITH MVFR CIGS ARE ALSO
ONGOING IN THE KLAMATH BASIN, BUT THESE SHOWERS WILL DECREASE
AROUND DAYBREAK. SHOWERS ARE MUCH MORE ISOLATED WITH GENERAL VFR
CONDITIONS ELSEWHERE ON THE EAST SIDE AND CALIFORNIA. -WRIGHT
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR ORZ029.
CA...FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR CAZ084.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
UNTIL 11 PM PDT THIS EVENING FOR PZZ350.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT THIS
MORNING FOR PZZ356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ370-376.
$$
000
FXUS66 KMFR 230333
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
833 PM PDT WED MAY 22 2013
.DISCUSSION...ALREADY MADE AN UPDATE THIS EVENING, PRIMARILY TO
RAISE POPS ALONG THE COOS COAST ACROSS THE UMPQUA INTO THE NORTH
CASCADES. A BROAD UPPER LOW CONTINUES TO SPIN OVER THE PACNW THIS
EVENING AND IS CURRENTLY CENTERED OVER SW WASHINGTON. A STEADY
STREAM OF MOISTURE CONTINUES TO IMPACT NORTHERN SECTION OF MY
FORECAST AREA. WEBCAMS SHOW WET CONDITIONS AND MANY SITES FROM
COOS COUNTY EAST INTO THE CASCADES CONTINUE TO RECORD
PRECIPITATION, AND THIS WAS THE PURPOSE OF THE UPDATE. FURTHER
SOUTH, SHOWERS ARE MORE ISOLATED BUT BECAUSE OF A DEEP NEARLY
SATURATED PROFILE, THEY ARE COMING DOWN HEAVY AT TIMES. SHOWERS
ARE EVEN MORE ISOLATED EAST OF THE CASCADES AND IN CALIFORNIA AND
AS A RESULT, I`VE KEPT POPS MUCH LOWER OVER THERE.
WE WILL HAVE TO KEEP AN EYE ON ANY IMPULSES ROTATING AROUND THE
UPPER LOW WHICH COULD INCREASE SHOWER ACTIVITY. BUT FOR THE TIME
BEING, IT LOOKS AS IF NORTHERN AREAS WILL REMAIN THE FOCUS AND THE
REST OF US WILL BE DODGING SPOTTIER ACTIVITY. ALL AREAS WILL
REMAIN MUCH COOLER THAN NORMAL FOR THE NEXT SEVERAL DAYS THOUGH.
CLOUDS WILL KEEP US FROM SEEING ANY FROST/FREEZE IMPACTS OVER WEST
SIDE AG AREAS, BUT SOME EAST SIDE AND NORCAL GROWING AREAS ARE
CURRENTLY UNDER FREEZE WARNINGS AND FROST ADVISORIES, AND I SEE NO
COMPELLING REASON TO CHANGE THOSE. -WRIGHT
&&
.AVIATION...AREAS OF MVFR CIGS AND AREAS OF OBSCURED MOUNTAINS ARE
EXPECTED THROUGH THE EVENING. AREAS OF MVFR CIGS AND
VISIBILITIES WILL PERSIST NEAR THE COAST AND IN THE UMPQUA BASIN
LATE TONIGHT THROUGH THURSDAY MORNING. OTHERWISE...CONDITIONS WILL
IMPROVE TO VFR LATE TONIGHT. ANOTHER DISTURBANCE WILL REACH THE
COAST BY THURSDAY AFTERNOON...AND WILL LIKELY PUSH MORE
PRECIPITATION AND AREAS OF MVFR INTO THE REGION. -BPN
&&
.PREV DISCUSSION... /ISSUED 313 PM PDT WED MAY 22 2013/
SHORT TERM...AN UPPER LOW WILL REMAIN OVER THE REGION THROUGH
FRIDAY...WEAKENING AND SHIFTING NORTH SLIGHTLY ON SATURDAY. THIS
LOW WILL GRADUALLY FILL AND THE AIR MASS WILL GRADUALLY WARM.
CONTINUED MOISTURE AND SHORTWAVES WILL MOVE INTO THE CWA OVER THE
NEXT FEW DAYS AND BRING SHOWERS. THE PREFERRED AREA FOR SHOWER
ACTIVITY WILL BE ACROSS THE COAST AND THE UMPQUA AS WELL AS THE
SOUTHERN OREGON CASCADES WITH AREAS OF SHOWERS MOVING INTO OTHER
WEST SIDE LOCATIONS AND EAST OF THE CASCADES AT TIMES.
A SHORTWAVE IS MOVING INLAND THIS AFTERNOON AND EVENING AND IS
BRINGING SCATTERED SHOWERS TO AREAS FROM THE CASCADES WEST.
SHOWER ACTIVITY IS EXPECTED TO INCREASE ACROSS THE WEST SIDE IN
THIS AFTERNOON AND EVENING AND SPREAD INTO SOME EAST SIDE LOCATIONS AS
WELL. SOME OF THE SHOWERS MAY BRING SMALL HAIL AND GUSTY WINDS
THIS AFTERNOON INTO THIS EVENING. MODELS SHOW SOME MARGINAL
INSTABILITY IN NORTHERN LAKE COUNTY. EXPECT MAINLY SCATTERED
SHOWERS TO DEVELOP THERE BUT THINK THE CHANCE FOR ANY
THUNDERSTORMS IS LOW.
SHOWER ACTIVITY IS EXPECTED TO CONTINUE INTO THE EVENING FOR MANY
LOCATIONS WITH SHOWERS DECREASING OVERNIGHT. COLD OVERNIGHT
TEMPERATURES ARE EXPECTED AGAIN TONIGHT INTO THURSDAY MORNING.
SKIES WILL LIKELY STAY CLOUDY OVERNIGHT WITH SOME PARTIAL
CLEARING OVER INLAND AREAS DURING THE EARLY MORNING. TEMPERATURES
THURSDAY MORNING WILL LIKELY BE SIMILAR OR JUST A COUPLE DEGREES
WARMER THAN THIS MORNING. PARTIAL CLEARING THOUGH MAY ALLOW MORE
FROST FORMATION THURSDAY MORNING. HAVE INCLUDED MENTION OF PATCHY
FROST IN THE WESTERN OREGON VALLEYS INCLUDING THE ROGUE AND
ILLINOIS VALLEYS AND AREAS OF FROST INTO THE SHASTA VALLEY IN
CALIFORNIA. OVER THE KLAMATH BASIN EXPECT FREEZING AND BELOW
FREEZING CONDITIONS.
ON THURSDAY...EXPECT SOME SCATTERED SHOWERS DURING THE DAY. THEN
MODELS SHOW INCREASED SHOWER ACTIVITY DURING THE EVENING AND
CONTINUING INTO FRIDAY MORNING AS A MODERATE VORT MAX ASSOCIATED
WITH THE UPPER LOW MOVES INTO THE AREA. THE BEST CHANCE FOR SHOWERS
WILL BE FROM THE SOUTHERN OREGON CASCADES WEST WITH ISOLATED TO
SCATTERED SHOWERS EAST OF THE CASCADES AND INTO PORTIONS OF
NORTHERN CALIFORNIA.
SHOWERS ARE EXPECTED TO DECREASE FRIDAY AFTERNOON AND EVENING AS
THE SHORTWAVE MOVES NORTHEAST AND OUT THE AREA. THE UPPER
TROUGH REMAINS OVER THE REGION FRIDAY NIGHT AND SATURDAY...ALTHOUGH
WEAKER AND CENTERED FURTHER NORTH. THIS WILL BRING THE POTENTIAL
FOR ADDITIONAL AREAS OF SCATTERED SHOWERS ON SATURDAY. MODELS HAVE
TRENDED LOWER ON THE SHOWER ACTIVITY THOUGH SO HAVE LOWERED THE
CHANCE OF PRECIPITATION FOR SATURDAY. WEAK INSTABILITY STILL IS
PRESENT EAST OF THE CASCADES SO HAVE KEPT A SLIGHT CHANCE FOR
THUNDERSTORMS...MAINLY IN LAKE COUNTY...SATURDAY AFTERNOON AND
EVENING.
LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY NIGHT...
THE 12Z GFS AND ECMWF STILL AGREE ON THE CHARACTER OF THE LONG TERM
FORECAST. THE UPPER LEVEL PATTERN SHOWS A CONTINUATION OF A LONGWAVE
TROUGH WITH A SERIES OF DISTURBANCES TO AFFECT OUR REGION FROM THE
WEEKEND ALL THE WAY THROUGH NEXT WEEK. TEMPERATURES WILL MOSTLY
RANGE FROM SLIGHTLY BELOW NORMAL TO NEAR NORMAL THROUGH THE PERIOD.
DESPITE THE AGREEMENT AND HIGH CONFIDENCE ON THE BIG PICTURE...THE
GFS AND ECMWF SOLUTIONS BEGIN TO DIVERGE ON SATURDAY AND DIFFERENCES
BECOME SIGNIFICANT ALREADY BY SATURDAY NIGHT. ON SATURDAY NIGHT, THE
EC RETROGRADES THE MAIN UPPER TROUGH TO OFFSHORE OF WASHINGTON WHILE
THE GFS IS MORE SIMILAR TO ITS SOLUTION FROM YESTERDAY WITH THE MAIN
TROUGH MOVING NORTHEAST TO INLAND BRITISH COLUMBIA AND A SECONDARY
LOBE OVER OUR AREA. THE MAIN EFFECT IS THAT THE PROBABILITY OF EAST
SIDE SHOWERS AND A FEW EAST SIDE EVENING THUNDERSTORMS IS HIGHER WITH
THE GFS WHILE THE WESTERLY FLOW FROM THE EC WOULD FAVOR SCATTERED
SHOWERS ON THE WEST SIDE OF THE CASCADES.
THE GFS SOLUTION IS WARMER THAN THE EC ON SUNDAY. I WENT WITH A
MODEL BLEND FOR THE TEMPERATURE FORECAST. BOTH MODELS HAVE SOME
VERSION OF A WEAK FRONT CROSSING THE AREA. THE EC DEPICTED FRONT
WOULD BE STRONGER BUT FOCUSED NORTH OF THE UMPQUA DIVIDE WHILE THE
GFS SOLUTION WOULD BRING MORE WIDESPREAD BUT MAINLY LIGHT SHOWERS.
THE MODEL SOLUTIONS FOR MEMORIAL DAY HAVE CHANGED SIGNIFCANTLY WITH
THE GFS UPPER LEVEL PATTERN BECOMING MORE PROGRESSIVE AND THE ECMWF
LESS PROGRESSIVE. IN THE ECMWF CASE...THE UPPER TROUGH LINGERS
OVER THE PACIFIC NORTHWEST WITH A COLD FRONT MOVING SOUTHEAST
TOWARD OUR AREA WHILE THE GFS SHOWS BRIEF WEAK RIDGING SUNDAY
NIGHT THEN THE NEXT UPPER TROUGH ALREADY APPROACHING THE COAST.
THE COMMONALITY IS THAT BOTH MODELS HAVE TRENDED COOLER AND
WETTER. THERE IS STILL A SIZEABLE POSSIBILITY THAT MONDAY MORNING
WILL BE DRY. BUT I HAVE RAISED THE PROBABILITY OF RAIN FOR MONDAY
AND IT REMAINS ABOVE CLIMATOLOGICAL NORMAL THROUGH TUESDAY. A
MOIST ONSHORE FLOW IS FORECAST TO CONTINUE ON WEDNESDAY WITH A
SLIGHT CHANCE TO CHANCE OF LIGHT SHOWERS. /DW
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING FROM 2 AM TO 9 AM PDT THURSDAY FOR ORZ029.
CA...FREEZE WARNING FROM 2 AM TO 9 AM PDT THURSDAY FOR CAZ084.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
UNTIL 11 PM PDT THURSDAY FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THURSDAY
FOR PZZ370-376.
$$
000
FXUS66 KMFR 222217 CCA
AFDMFR
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MEDFORD OR
313 PM PDT WED MAY 22 2013
.SHORT TERM...AN UPPER LOW WILL REMAIN OVER THE REGION THROUGH
FRIDAY...WEAKENING AND SHIFTING NORTH SLIGHTLY ON SATURDAY. THIS
LOW WILL GRADUALLY FILL AND THE AIR MASS WILL GRADUALLY WARM.
CONTINUED MOISTURE AND SHORTWAVES WILL MOVE INTO THE CWA OVER THE
NEXT FEW DAYS AND BRING SHOWERS. THE PREFERRED AREA FOR SHOWER
ACTIVITY WILL BE ACROSS THE COAST AND THE UMPQUA AS WELL AS THE
SOUTHERN OREGON CASCADES WITH AREAS OF SHOWERS MOVING INTO OTHER
WEST SIDE LOCATIONS AND EAST OF THE CASCADES AT TIMES.
A SHORTWAVE IS MOVING INLAND THIS AFTERNOON AND EVENING AND IS
BRINGING SCATTERED SHOWERS TO AREAS FROM THE CASCADES WEST.
SHOWER ACTIVITY IS EXPECTED TO INCREASE ACROSS THE WEST SIDE IN
THIS AFTERNOON AND EVENING AND SPREAD INTO SOME EAST SIDE LOCATIONS AS
WELL. SOME OF THE SHOWERS MAY BRING SMALL HAIL AND GUSTY WINDS
THIS AFTERNOON INTO THIS EVENING. MODELS SHOW SOME MARGINAL
INSTABILITY IN NORTHERN LAKE COUNTY. EXPECT MAINLY SCATTERED
SHOWERS TO DEVELOP THERE BUT THINK THE CHANCE FOR ANY
THUNDERSTORMS IS LOW.
SHOWER ACTIVITY IS EXPECTED TO CONTINUE INTO THE EVENING FOR MANY
LOCATIONS WITH SHOWERS DECREASING OVERNIGHT. COLD OVERNIGHT
TEMPERATURES ARE EXPECTED AGAIN TONIGHT INTO THURSDAY MORNING.
SKIES WILL LIKELY STAY CLOUDY OVERNIGHT WITH SOME PARTIAL
CLEARING OVER INLAND AREAS DURING THE EARLY MORNING. TEMPERATURES
THURSDAY MORNING WILL LIKELY BE SIMILAR OR JUST A COUPLE DEGREES
WARMER THAN THIS MORNING. PARTIAL CLEARING THOUGH MAY ALLOW MORE
FROST FORMATION THURSDAY MORNING. HAVE INCLUDED MENTION OF PATCHY
FROST IN THE WESTERN OREGON VALLEYS INCLUDING THE ROGUE AND
ILLINOIS VALLEYS AND AREAS OF FROST INTO THE SHASTA VALLEY IN
CALIFORNIA. OVER THE KLAMATH BASIN EXPECT FREEZING AND BELOW
FREEZING CONDITIONS.
ON THURSDAY...EXPECT SOME SCATTERED SHOWERS DURING THE DAY. THEN
MODELS SHOW INCREASED SHOWER ACTIVITY DURING THE EVENING AND
CONTINUING INTO FRIDAY MORNING AS A MODERATE VORT MAX ASSOCIATED
WITH THE UPPER LOW MOVES INTO THE AREA. THE BEST CHANCE FOR SHOWERS
WILL BE FROM THE SOUTHERN OREGON CASCADES WEST WITH ISOLATED TO
SCATTERED SHOWERS EAST OF THE CASCADES AND INTO PORTIONS OF
NORTHERN CALIFORNIA.
SHOWERS ARE EXPECTED TO DECREASE FRIDAY AFTERNOON AND EVENING AS
THE SHORTWAVE MOVES NORTHEAST AND OUT THE AREA. THE UPPER
TROUGH REMAINS OVER THE REGION FRIDAY NIGHT AND SATURDAY...ALTHOUGH
WEAKER AND CENTERED FURTHER NORTH. THIS WILL BRING THE POTENTIAL
FOR ADDITIONAL AREAS OF SCATTERED SHOWERS ON SATURDAY. MODELS HAVE
TRENDED LOWER ON THE SHOWER ACTIVITY THOUGH SO HAVE LOWERED THE
CHANCE OF PRECIPITATION FOR SATURDAY. WEAK INSTABILITY STILL IS
PRESENT EAST OF THE CASCADES SO HAVE KEPT A SLIGHT CHANCE FOR
THUNDERSTORMS...MAINLY IN LAKE COUNTY...SATURDAY AFTERNOON AND
EVENING.
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY NIGHT...
THE 12Z GFS AND ECMWF STILL AGREE ON THE CHARACTER OF THE LONG TERM
FORECAST. THE UPPER LEVEL PATTERN SHOWS A CONTINUATION OF A LONGWAVE
TROUGH WITH A SERIES OF DISTURBANCES TO AFFECT OUR REGION FROM THE
WEEKEND ALL THE WAY THROUGH NEXT WEEK. TEMPERATURES WILL MOSTLY
RANGE FROM SLIGHTLY BELOW NORMAL TO NEAR NORMAL THROUGH THE PERIOD.
DESPITE THE AGREEMENT AND HIGH CONFIDENCE ON THE BIG PICTURE...THE
GFS AND ECMWF SOLUTIONS BEGIN TO DIVERGE ON SATURDAY AND DIFFERENCES
BECOME SIGNIFICANT ALREADY BY SATURDAY NIGHT. ON SATURDAY NIGHT, THE
EC RETROGRADES THE MAIN UPPER TROUGH TO OFFSHORE OF WASHINGTON WHILE
THE GFS IS MORE SIMILAR TO ITS SOLUTION FROM YESTERDAY WITH THE MAIN
TROUGH MOVING NORTHEAST TO INLAND BRITISH COLUMBIA AND A SECONDARY
LOBE OVER OUR AREA. THE MAIN EFFECT IS THAT THE PROBABILITY OF EAST
SIDE SHOWERS AND A FEW EAST SIDE EVENING THUNDERSTORMS IS HIGHER WITH
THE GFS WHILE THE WESTERLY FLOW FROM THE EC WOULD FAVOR SCATTERED
SHOWERS ON THE WEST SIDE OF THE CASCADES.
THE GFS SOLUTION IS WARMER THAN THE EC ON SUNDAY. I WENT WITH A
MODEL BLEND FOR THE TEMPERATURE FORECAST. BOTH MODELS HAVE SOME
VERSION OF A WEAK FRONT CROSSING THE AREA. THE EC DEPICTED FRONT
WOULD BE STRONGER BUT FOCUSED NORTH OF THE UMPQUA DIVIDE WHILE THE
GFS SOLUTION WOULD BRING MORE WIDESPREAD BUT MAINLY LIGHT SHOWERS.
THE MODEL SOLUTIONS FOR MEMORIAL DAY HAVE CHANGED SIGNIFCANTLY WITH
THE GFS UPPER LEVEL PATTERN BECOMING MORE PROGRESSIVE AND THE ECMWF
LESS PROGRESSIVE. IN THE ECMWF CASE...THE UPPER TROUGH LINGERS
OVER THE PACIFIC NORTHWEST WITH A COLD FRONT MOVING SOUTHEAST
TOWARD OUR AREA WHILE THE GFS SHOWS BRIEF WEAK RIDGING SUNDAY
NIGHT THEN THE NEXT UPPER TROUGH ALREADY APPROACHING THE COAST.
THE COMMONALITY IS THAT BOTH MODELS HAVE TRENDED COOLER AND
WETTER. THERE IS STILL A SIZEABLE POSSIBILITY THAT MONDAY MORNING
WILL BE DRY. BUT I HAVE RAISED THE PROBABILITY OF RAIN FOR MONDAY
AND IT REMAINS ABOVE CLIMATOLOGICAL NORMAL THROUGH TUESDAY. A
MOIST ONSHORE FLOW IS FORECAST TO CONTINUE ON WEDNESDAY WITH A
SLIGHT CHANCE TO CHANCE OF LIGHT SHOWERS. /DW
&&
.AVIATION...A WEAKENING DISTURBANCE IS MOVING ACROSS THE AREA
THIS AFTERNOON. SCATTERED SHOWERS...AREAS OF MVFR CIGS AND AREAS
OF OBSCURED MOUNTAINS ARE EXPECTED THROUGH THE EVENING. AREAS OF
MVFR CIGS WILL PERSIST NEAR THE COAST AND IN THE UMPQUA BASIN LATE
TONIGHT THROUGH THURSDAY MORNING. OTHERWISE...CONDITIONS WILL
IMPROVE TO VFR LATE TONIGHT. ANOTHER DISTURBANCE WILL REACH THE
COAST BY THURSDAY AFTERNOON.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING FROM 2 AM TO 9 AM PDT THURSDAY FOR ORZ029.
CA...FREEZE WARNING FROM 2 AM TO 9 AM PDT THURSDAY FOR CAZ084.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
11 PM PDT THURSDAY FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THURSDAY
FOR PZZ370-376.
$$
CC
000
FXUS66 KMFR 222157
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
257 PM PDT WED MAY 22 2013
.SHORT TERM...AN UPPER LOW WILL REMAIN OVER THE REGION THROUGH
FRIDAY...WEAKENING AND SHIFTING NORTH SLIGHTLY ON SATURDAY. THIS
LOW WILL GRADUALLY FILL AND THE AIR MASS WILL GRADUALLY WARM.
CONTINUED MOISTURE AND SHORTWAVES WILL MOVE INTO THE CWA OVER THE
NEXT FEW DAYS AND BRING SHOWERS. THE PREFERRED AREA FOR SHOWER
ACTIVITY WILL BE ACROSS THE COAST AND THE UMPQUA AS WELL AS THE
SOUTHERN OREGON CASCADES WITH AREAS OF SHOWERS MOVING INTO OTHER
WEST SIDE LOCATIONS AND EAST OF THE CASCADES AT TIMES.
A SHORTWAVE IS MOVING INLAND THIS AFTERNOON AND EVENING AND IS
BRINGING SCATTERED SHOWERS TO AREAS FROM THE CASCADES WEST.
SHOWER ACTIVITY IS EXPECTED TO INCREASE ACROSS THE WEST SIDE IN
THIS AFTERNOON AND EVENING AND SPREAD INTO SOME EAST SIDE LOCATIONS AS
WELL. SOME OF THE SHOWERS MAY BRING SMALL HAIL AND GUSTY WINDS
THIS AFTERNOON INTO THIS EVENING. MODELS SHOW SOME MARGINAL
INSTABILITY IN NORTHERN LAKE COUNTY. EXPECT MAINLY SCATTERED
SHOWERS TO DEVELOP THERE BUT THINK THE CHANCE FOR ANY
THUNDERSTORMS IS LOW.
SHOWER ACTIVITY IS EXPECTED TO CONTINUE INTO THE EVENING FOR MANY
LOCATIONS WITH SHOWERS DECREASING OVERNIGHT. COLD OVERNIGHT
TEMPERATURES ARE EXPECTED AGAIN TONIGHT INTO THURSDAY MORNING.
SKIES WILL LIKELY STAY CLOUDY OVERNIGHT WITH SOME PARTIAL
CLEARING OVER INLAND AREAS DURING THE EARLY MORNING. TEMPERATURES
THURSDAY MORNING WILL LIKELY BE SIMILAR OR JUST A COUPLE DEGREES
WARMER THAN THIS MORNING. PARTIAL CLEARING THOUGH MAY ALLOW MORE
FROST FORMATION THURSDAY MORNING. HAVE INCLUDED MENTION OF PATCHY
FROST IN THE WESTERN OREGON VALLEYS INCLUDING THE ROGUE AND
ILLINOIS VALLEYS AND AREAS OF FROST INTO THE SHASTA VALLEY IN
CALIFORNIA. OVER THE KLAMATH BASIN EXPECT FREEZING AND BELOW
FREEZING CONDITIONS.
ON THURSDAY...EXPECT SOME SCATTERED SHOWERS DURING THE DAY. THEN
MODELS SHOW INCREASED SHOWER ACTIVITY DURING THE EVENING AND
CONTINUING INTO FRIDAY MORNING AS A MODERATE VORT MAX ASSOCIATED
WITH THE UPPER LOW MOVES INTO THE AREA. THE BEST CHANCE FOR SHOWERS
WILL BE FROM THE SOUTHERN OREGON CASCADES WEST WITH ISOLATED TO
SCATTERED SHOWERS EAST OF THE CASCADES AND INTO PORTIONS OF
NORTHERN CALIFORNIA.
SHOWERS ARE EXPECTED TO DECREASE FRIDAY AFTERNOON AND EVENING AS
THE SHORTWAVE MOVES NORTHEAST AND OUT THE AREA. THE UPPER
TROUGH REMAINS OVER THE REGION FRIDAY NIGHT AND SATURDAY...ALTHOUGH
WEAKER AND CENTERED FURTHER NORTH. THIS WILL BRING THE POTENTIAL
FOR ADDITIONAL AREAS OF SCATTERED SHOWERS ON SATURDAY. MODELS HAVE
TRENDED LOWER ON THE SHOWER ACTIVITY THOUGH SO HAVE LOWERED THE
CHANCE OF PRECIPITATION FOR SATURDAY. WEAK INSTABILITY STILL IS
PRESENT EAST OF THE CASCADES SO HAVE KEPT A SLIGHT CHANCE FOR
THUNDERSTORMS...MAINLY IN LAKE COUNTY...SATURDAY AFTERNOON AND
EVENING.
.LONG TERM...
&&
.AVIATION...A WEAKENING DISTURBANCE IS MOVING ACROSS THE AREA
THIS AFTERNOON. SCATTERED SHOWERS...AREAS OF MVFR CIGS AND AREAS
OF OBSCURED MOUNTAINS ARE EXPECTED THROUGH THE EVENING. AREAS OF
MVFR CIGS WILL PERSIST NEAR THE COAST AND IN THE UMPQUA BASIN LATE
TONIGHT THROUGH THURSDAY MORNING. OTHERWISE...CONDITIONS WILL
IMPROVE TO VFR LATE TONIGHT. ANOTHER DISTURBANCE WILL REACH THE
COAST BY THURSDAY AFTERNOON.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING FROM 2 AM TO 9 AM PDT THURSDAY FOR ORZ029.
CA...FREEZE WARNING FROM 2 AM TO 9 AM PDT THURSDAY FOR CAZ084.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THURSDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THURSDAY
FOR PZZ370-376.
$$
CC
| 
