Debris Flow in California, September 24, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
301 PM PDT WED SEP 24 2014

.SHORT TERM...A STRONG FRONT WITH DEEP MOISTURE AND GOOD UPPER
LEVEL SUPPORT IS LOCATED JUST WEST OF THE CASCADES AND IS BRINGING
MODERATE TO LOCALLY HEAVY RAINFALL TO AREAS FROM THE CASCADES
WESTWARD TO THE COAST MOUNTAINS. RAINFALL HAS DECREASED ALONG
THE COAST ON THE BACKSIDE OF THE FRONT. MODELS CONTINUE TO SHOW
THAT THIS FRONT WILL SLOWLY MOVE EASTWARD ACROSS THE CASCADES AND
EAST SIDE LATE THIS AFTERNOON THROUGH THURSDAY MORNING. GIVEN THE
DEEP MOISTURE WITH PRECIPITABLE WATER VALUES OF 1.8 INCHES JUST
OFF THE NORTHERN CALIFORNIA COAST AND THE SLOW MOVEMENT OF THE
FRONT, EXPECT MODERATE TO LOCALLY HEAVY RAINFALL TO AFFECT AREAS
FROM THE CASCADES WEST THIS AFTERNOON INTO THIS EVENING WITH LIGHT
TO MODERATE RAINFALL EXPECTED TO SPREAD EAST OF THE CASCADES THIS
EVENING THROUGH THURSDAY MORNING.

SOUTH WINDS AHEAD OF THE FRONT HAVE BEEN STRONG AND GUSTY IN AREAS
EAST OF THE CASCADES WITH GUSTS TO AROUND 35 MPH IN THE VALLEYS
AND GUSTS TO 45 MPH IN THE MOUNTAINS. THESE WINDS ARE EXPECTED TO
CONTINUE INTO THE EVENING, THEN DECREASE AFTER SUNSET. IN THE
SHASTA VALLEY, SOUTH TO SOUTHEAST WINDS WITH GUSTS TO AROUND 45 TO
50 MPH ARE EXPECTED TO TAPER OFF BY LATE AFTERNOON WITH WINDS
SWITCHING TO THE NORTHWEST AND BECOMING LIGHTER.

BEHIND THE FRONT, SATELLITE IMAGERY SHOWS AN AREA OF DIMINISHED
SHOWERS AND CLEARING FOLLOWED BY ADDITIONAL SHOWERS NEAR AND AND
SOUTH OF THE CORE OF THE LOW. THESE ADDITIONAL SHOWERS ARE
EXPECTED TO MOVE INLAND THURSDAY MORNING AND AFTERNOON AS THE
UPPER TROUGH BEGINS TO PUSH INLAND. COLD AIR ALOFT WILL HELP
DESTABILIZE THE ATMOSPHERE THURSDAY AND SUPPORT SHOWERS. HOWEVER
PRECIPITABLE WATER VALUES WILL BE MUCH LESS THAN TODAY. SO EXPECT
MORE SCATTERED SHOWER ACTIVITY. WEAK INSTABILITY IS EXPECTED OVER
MUCH OF THE AREA THURSDAY AFTERNOON INTO THURSDAY EVENING  AS THE
COLD POOL ALOFT MOVES INLAND. OF NOTE IS THAT MODELS ARE INDICATING
THE GREATEST INSTABILITY OVER THE CASCADES AND INTO EASTERN LAKE
COUNTY. GIVEN THAT THIS INSTABILITY IS WEAK AND THE COLD POOL
ALOFT IS AROUND -17 TO -19 AT 500 MB, HAVE LEANED TOWARDS SHOWERS
ONLY AND HAVE KEPT THUNDERSTORMS OUT OF THE FORECAST. HOWEVER,
WILL NEED TO KEEP WATCH ON THE POTENTIAL FOR THUNDERSTORMS. OVER
THE COASTAL WATERS INSTABILITY IS SLIGHTLY GREATER SO HAVE ADDED A
SLIGHT CHANCE FOR THUNDERSTORMS TO THE COASTAL WATERS FORECAST ON
THURSDAY.

IN ADDITION TO SHOWERS, THIS UPPER TROUGH WILL BRING CONTINUED
COOL DAYTIME TEMPERATURES TO THE AREA ON THURSDAY.

ON FRIDAY, THE UPPER TROUGH IS EXPECTED TO DEEPEN TO THE SOUTH WITH
A CLOSED UPPER LOW  FORECAST TO DEVELOP OVER CENTRAL CALIFORNIA BY
LATE FRIDAY. A RELATIVELY MOIST AIR MASS REMAINS OVER THE AREA ON
FRIDAY AND WITH INCREASING INSTABILITY EXPECT SHOWERS WITH SOME
ISOLATED THUNDERSTORMS TO DEVELOP DURING THE DAY FRIDAY AND FRIDAY
EVENING. THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS FRIDAY IS
FROM THE WESTERN CASCADES FOOTHILLS EAST IN SOUTHERN OREGON AND
OVER NORTHERN CALIFORNIA.

.LONG TERM...SATURDAY THROUGH MONDAY...MODELS ARE IN GOOD
AGREEMENT THAT THE UPPER LOW OVER CENTRAL CALIFORNIA WILL SHIFT
EASTWARD ON SATURDAY BECOMING CENTERED OVER NEVADA...THEN  IT
WILL LINGER OVER THE NEVADA AREA ON SUNDAY BEFORE SHIFTING
NORTHEAST ON MONDAY AS ANOTHER UPPER TROUGH MOVES INTO THE
NORTHERN PACNW. AS THE CLOSED LOW REMAINS JUST SOUTHEAST OF THE AREA
SATURDAY INTO SUNDAY....EXPECT ADDITIONAL SHOWERS TO DEVELOP,
MAINLY FOR AREAS EAST OF THE CASCADES. THEN ON MONDAY, AS A LOW
PRESSURE SYSTEM TO THE NORTH MOVES INTO BRITISH COLUMBIA AND A
FRONT IS FORECAST TO PUSH INTO THE WASHINGTON AND OREGON COASTS, THERE
IS A CHANCE FOR LIGHT RAIN SHOWERS, MAINLY FROM THE CASCADES WEST
IN SOUTHERN OREGON. MODEL SOLUTIONS VARY ON THE TRACK AND TIMING
OF THIS SYSTEM THOUGH WITH THE ECMWF SHOWING A MORE SOUTHERLY
TRACK AND BRINGING MORE RAINFALL INTO THE AREA ON MONDAY COMPARED
TO THE GFS. HAVE GONE TOWARDS A BLEND OF THESE SOLUTIONS.

&&

.AVIATION...BASED ON THE 24/18Z TAF CYCLE...CONDITIONS HAVE IMPROVED
BEHIND THE FRONT ALONG THE NORTH COAST, INCLUDING KOTH...SO EXPECT A
MIX OF VFR/MVFR WITH ISOLATED SHOWERS THERE THE REST OF THIS
AFTERNOON THROUGH THURSDAY MORNING. MODERATE TO HEAVY RAINFALL WILL
ACCOMPANY A COLD FRONT THROUGH THE REMAINDER OF THE CWA THIS
AFTERNOON THROUGH THURSDAY MORNING WITH WIDESPREAD IFR/MVFR CIGS/VIS
AND NEAR TOTAL TERRAIN OBSCURATION. IMPROVING CONDITIONS CAN BE
EXPECTED FROM WEST TO EAST BEHIND THE FRONT OVERNIGHT WEST OF THE
CASCADES. GUSTY WINDS AND MOUNTAIN WAVE TURBULENCE WILL PERSIST EAST
OF KLAMATH FALLS THROUGH THIS EVENING, THEN EASE OVERNIGHT. SPILDE

&&

.MARINE...UPDATED 200 PM PDT WED 24 SEP 2014...SOUTH WINDS WILL
CONTINUE THROUGH THURSDAY AS LOW PRESSURE REMAINS OFFSHORE. WINDS
WILL BE STRONGEST NORTH OF GOLD BEACH BUT SHOULD REMAIN AT SMALL
CRAFT ADVISORY LEVELS AT WORST. A STEEP, HEAVY WEST SWELL CONTINUES
OVER THE WATERS THIS AFTERNOON AND WILL GRADUALLY DIMINISH TONIGHT.
THE COMBINATION OF SWELL AND WIND WAVE WILL KEEP SMALL CRAFT
ADVISORY CONDITIONS GOING OVER THE WATERS THROUGH THURSDAY WITH THE
HEAVIEST SEAS NORTH OF CAPE BLANCO. A LOW PRESSURE TROUGH MOVES
THROUGH FRIDAY WITH LIGHT AND VARIABLE WINDS AND MODERATE SEAS DUE
TO WEST SWELL. WINDS WILL TURN NORTH THIS WEEKEND AS LOW PRESSURE
MOVES INLAND AND HIGH PRESSURE BUILDS OFF SHORE. -WRIGHT

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR ORZ624-625.

CA...RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR CAZ285.
     FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR CAZ080-081-083.
     WIND ADVISORY UNTIL 5 PM PDT THIS AFTERNOON FOR CAZ080>083.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THURSDAY FOR
     PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT FRIDAY
     FOR PZZ350-356-370-376.

CC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
201 PM PDT WED SEP 24 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0130 PM     HEAVY RAIN       1 N ROSEBURG            43.23N 123.36W
09/24/2014  M1.20 INCH       DOUGLAS            OR   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS HEAVY RAIN OF 1.20
            INCHES SINCE MIDNIGHT. LIGHT TO MODERATE
            RAIN IS CONTINUING TO FALL IN THE AREA.
            HEAVY RAIN DURATION 13 HOURS 30 MINUTES.
            OBSERVER LOCATION NW EDEN HEIGHTS TOP OF
            HILL.

&&

BS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
223 PM PDT WED SEP 24 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1230 PM     HEAVY RAIN       3 SE NESIKA BEACH       42.47N 124.38W
09/24/2014  M4.26 INCH       CURRY              OR   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS 4.26 INCHES OF RAIN
            SINCE 6:00 PM LAST NIGHT. HEAVY RAIN
            DURATION 18 HOURS 30 MINUTES. OBSERVER
            LOCATION 3 MI UP ROGUE RIVER.

&&

BS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
328 PM PDT WED SEP 24 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0315 PM     HEAVY RAIN       2 WSW OBRIEN            42.06N 123.73W
09/24/2014  M1.30 INCH       JOSEPHINE          OR   TRAINED SPOTTER

            SPOTTER REPORTS 1.3 INCHES OF RAINFALL SINCE
            3:00 AM THIS MORNING. IT IS CURRENTLY
            DRIZZLING IN THE AREA. HEAVY RAIN DURATION
            12 HOURS 15 MINUTES. OBSERVER LOCATION 1.6
            MILES FROM HWY 199 IN O BRIEN.

&&

BS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
425 PM PDT WED SEP 24 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     HEAVY RAIN       2 ESE JACKSONVILLE      42.30N 122.92W
09/24/2014  M1.00 INCH       JACKSON            OR   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS 1.00 INCH OF RAIN
            SINCE THE RAIN BEGAN. HEAVY RAIN DURATION 24
            HOURS. OBSERVER LOCATION ABOUT 3 MI EAST OF
            JACKSONVILLE.

&&

BS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
433 PM PDT WED SEP 24 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     HEAVY RAIN       4 NNE TAKILMA           42.11N 123.58W
09/24/2014  M1.14 INCH       JOSEPHINE          OR   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS 1.14 INCHES OF STORM
            TOTAL RAINFALL. HEAVY RAIN DURATION 24
            HOURS. OBSERVER LOCATION NEAR JCT. OF
            HOLLAND LOOP & DICK GRG.

&&

BS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
437 PM PDT WED SEP 24 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     HEAVY RAIN       2 N MERLIN              42.54N 123.41W
09/24/2014  M0.92 INCH       JOSEPHINE          OR   NWS EMPLOYEE

            AN NWS EMPLOYEE REPORTS 0.92 INCHES OF RAIN
            AT THE SPRAGUE SEED ORCHARD. IT IS STILL
            RAINING LIGHTLY. HEAVY RAIN DURATION 14
            HOURS.

&&

BS