Wildfire in California, July 1 to 25, 2014

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MEDFORD OR
209 PM PDT TUE JUL 1 2014

CORRECTED TO ADD FIRE WEATHER DISCUSSION.

.DISCUSSION...01/12Z NAM/GFS IN.

THE PUMP IS CURRENTLY BEING PRIMED FOR CONVECTIVE ACTIVITY OVER
SOUTHERN OREGON AND NORTHERN CALIFORNIA. FIRST...THE MOISTURE
FACTOR. THE 01/12Z KMFR SOUNDING SHOWED A PWAT OF 0.92...WHICH
IS FAIRLY HIGH. THE SECOND FACTOR IS INSTABILITY...AND SATELLITE
IMAGERY AND MODEL OUTPUT SHOWS A SHORT WAVE MOVING UP FROM THE
SOUTH LATE THIS AFTERNOON INTO THIS EVENING. IT WILL ALSO BE VERY
HOT INLAND TODAY...WHICH WILL HELP WITH THE HEAVY LIFTING.

MODELS SHOW NEGATIVE LIFTED INDICES AND PLENTY OF CAPE THIS
AFTERNOON AND EVENING...INITIALLY CENTERED OVER THE CASCADES THEN
SPREADING EAST AS THE EVENING PROGRESSES. EXPECT A LATE AFTERNOON
IN EARLY EVENING OUTBREAK OF THUNDERSTORMS...AND THEY WILL
INITIALLY BE DRY. INSTABILITY WILL LINGER INTO WEDNESDAY MORNING
EAST OF THE CASCADES...THEN A MORE WIDESPREAD AREA OF
THUNDERSTORMS WILL DEVELOP WEDNESDAY AFTERNOON OVER SISKIYOU
COUNTY NORTH INTO THE CASCADES AND NORTHEAST OVER MOST OF THE EAST
SIDE. BY THIS TIME THE THUNDERSTORMS WILL BE WET.

THE SHOW WILL END THURSDAY AS A WEAK INCOMING TROUGH WILL TURN
FLOW ALOFT TO THE SOUTHWEST...WHICH WILL CUT OFF THE MOISTURE
SOURCE TO THE AREA AND THE CONVECTION WILL SET UP FARTHER EAST. IT
WILL BE ABOUT TEN DEGREES COOLER OVER INLAND AREAS AS COMPARED TO
TODAY...BUT STILL ABOVE NORMAL. THIS PATTERN WILL PERSIST THROUGH
THE WEEKEND. THE FIRST HALF OF NEXT WEEK WILL BE CHARACTERIZED BY
ZONAL FLOW ALOFT AND A DEARTH OF EMBEDDED SHORT WAVE ACTIVITY...SO
EXPECT THE DRY AND HOT WEATHER TO CONTINUE THROUGH THAT STRETCH AS
WELL.

&&

.AVIATION...BASED ON THE 01/18Z TAFS...MOISTURE WILL PUSH IN ALOFT
FROM THE CASCADES EASTWARD TODAY AS A WAVE OF LOW PRESSURE ARRIVES
FROM THE SOUTH. THIS LOW WILL RESULT IN ISOLATED TO SCATTERED
THUNDERSTORMS MAINLY FROM THE MARBLE MOUNTAINS, SISKIYOUS, AND
CASCADES EASTWARD THIS AFTERNOON AND POTENTIALLY OVERNIGHT. DUE TO
VERY DRY AIR BELOW THE CLOUD BASES, GUSTY WINDS WILL BE POSSIBLE
UNDER AND NEAR THESE CELLS. IFR STRATUS WILL PUSH ON TO THE COAST
AGAIN THIS EVENING, SPREADING INTO THE UMPQUA BASIN OVERNIGHT MORE
LIKELY AS MVFR CEILINGS. SK

&&

.MARINE...UPDATED TUE 1 JULY 150 PM PDT...
HIGH PRESSURE OFFSHORE IS WEAKENING TODAY AND THE THERMAL TROUGH
ALONG THE COAST HAS MOVED INLAND. THIS IS BRINGING DECREASING
WINDS AND SEAS. SOME STEEP AND CHOPPY SMALL CRAFT ADVISORY SEAS WILL
CONTINUE OVER THE OUTER COASTAL WATERS INTO THIS EVENING. THEN SEAS
WILL LOWER BELOW SMALL CRAFT ADVISORY LEVELS TONIGHT. HOWEVER A
THERMAL TROUGH IS EXPECTED TO REDEVELOP ALONG THE COAST ON WEDNESDAY
WITH HIGH PRESSURE STRENGTHENING OFFSHORE. THIS IS EXPECTED TO BRING
A LIMITED  AREA OF SMALL CRAFT ADVISORY WINDS AND SEAS TO THE WATERS
SOUTH OF CAPE BLANCO. THE THERMAL TROUGH MAY STRENGTHEN ON THURSDAY
AND CONTINUE INTO FRIDAY WITH ANOTHER ROUND OF ENHANCED NORTH WINDS
AND SEAS. WINDS ARE EXPECTED TO LOWER SATURDAY AS A WEAK FRONT MOVES
BY TO THE NORTH. THIS MAY BE BRIEF THOUGH WITH NORTH WINDS AND SEAS
BUILDING AGAIN SUNDAY INTO MONDAY. /CC

&&

.FIRE WEATHER...
THE LATEST WATER VAPOR IMAGE SHOWS A WEAK SHORTWAVE LOCATED IN
CENTRAL CAL. HIGH CLOUDS ON THE NORTH SIDE OF THE SHORTWAVE ARE
MOVING INTO SOUTHERN OREGON. IN THE LAST HOUR OR SO, CUMULUS
DEVELOPMENT IS BEING OBSERVED ALONG THE SIERRAS AND NEAR REDDING AND
MOVING NORTH TO NORTHEAST. MODELS CONTINUE TO SHOW MIXED DETAILS,
BUT THEY AGREE WITH MID LEVEL MOISTURE INCREASING OVER THE AREA
LATE THIS AFTERNOON. THUNDERSTORMS WILL LIKELY TRY TO INITIATE FROM
THE TRINITY ALPS AND MARBLE MOUNTAINS EAST TO MEDICINE LAKE AROUND
OR JUST AFTER MAX HEATING, AND THEN THE SHORTWAVE FROM THE SOUTH IS
LIKELY TO GET INTO THE MIX THIS EVENING AND OVERNIGHT. FORECAST
SOUNDINGS SHOW LIFTED INDICES FALLING TO -4C TO -7C ACROSS MUCH OF
THE AREA EAST OF THE MARBLE AND CASCADES OVERNIGHT. MOISTURE LOOKS
MARGINAL ON THE GFS, BUT NOT THE NAM FOR TONIGHT. THOUGH WE HAVE
HIGHER CONFIDENCE IN THUNDERSTORMS REACHING SCATTERED LEVELS ON
WEDNESDAY ANY STORMS THROUGH TONIGHT ARE LIKELY TO BE DRY AND BE
ACCOMPANIED BY GUSTY OUTFLOW WINDS. ANTICIPATE STORMS WILL LIKELY
FOCUS IN FIRE WEATHER ZONES 284, 623, AND 624 TODAY, AND 624 AND 625
TOMORROW. ON WEDNESDAY, THE MODELS SHOW INCREASING MID LEVEL
MOISTURE ALONG THE SOUTHERN PORTION OF FIRE ZONE 280 AND POINTS
NORTHEAST ALONG WITH LIFTED INDICIES BETWEEN -3 AND -5C. A SHORTWAVE
IS EXPECTED TO ARRIVE LATE IN THE AFTERNOON AROUND THE TIME OF MAX
HEATING, THEREFORE CONFIDENCE IS MODERATE FOR MORE FREQUENT STORM
ACTIVITY AND HAVE DECIDED TO EXTEND THE RED FLAG WARNING FOR FIRE
ZONES 280...281...282 AND PART OF 284. -BTL/PETRUCELLI

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT WEDNESDAY
        FOR ORZ624-625.
     RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 11 AM PDT WEDNESDAY
        FOR ORZ623.

CA...RED FLAG WARNING FROM 5 PM THIS AFTERNOON TO 5 AM PDT WEDNESDAY
        FOR CAZ280>282-284-285.

PACIFIC COASTAL WATERS...NONE.

15/15/02