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000
FXUS66 KMFR 010407
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
907 PM PDT THU JUL 31 2014

.DISCUSSION...THUNDERSTORMS ARE WINDING DOWN ACROSS THE AREA THIS
EVENING WITH THE MOST LIGHTNING STRIKES NOW IN NORTHERN PORTIONS OF
LAKE COUNTY AND ALSO OVER THE WARNERS IN MODOC COUNTY. EXPECT
THESE WILL ALSO CONTINUE TO LESSEN AS THE EVENING PROGRESSES. THE
RED FLAG WARNING FOR FIRE ZONES 280, 281 AND 621 WAS CANCELLED
EARLIER THIS EVENING AS THUNDERSTORM COVERAGE IN THOSE ZONES WAS
MINIMAL. WILL LIKELY ALLOW THE REMAINDER OF THE RED FLAG WARNING
TO EXPIRE AT 11 PM PDT. AFTER MIDNIGHT EXPECT JUST A SLIGHT CHANCE
OF SHOWERS/ISOLATED THUNDER FROM THE CASCADES NEAR AND NORTH OF
CRATER LAKE EASTWARD TO THE CHRISTMAS VALLEY. ON FRIDAY,
THUNDERSTORM COVERAGE IS EXPECTED TO BE MUCH LESS THAN IT HAS BEEN
IN RECENT DAYS. STILL EXPECTING SOME ISOLATED MAINLY AFTERNOON AND
EVENING THUNDERSTORMS FROM THE CASCADE CREST EASTWARD ACROSS
NORTHERN KLAMATH AND LAKE COUNTIES SOUTHWARD TO THE WARNERS. THE
FORECAST HAS THIS HANDLED WELL AND WILL NOT UPDATE THIS EVENING.
SPILDE

&&

.AVIATION...BASED ON THE 01/00Z TAFS...

ALONG THE COAST...AREAS OF IFR CIGS/VSBYS WILL DEVELOP THIS
EVENING...THEN CLEAR TO VFR BY LATE MORNING FRIDAY. THE LOWER
CONDITIONS WILL RETURN TO THE SAME AREAS FRIDAY EVENING.
INLAND...VFR CONDITIONS WILL PREVAIL THROUGH FRIDAY EVENING.
HOWEVER...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
MAY PRODUCE AREAS OF TURBULENCE WITH GUSTY OUTFLOW WINDS AND HAIL.
STOCKTON

&&

.MARINE...UPDATED 230 PM PDT 31 JULY 2014...

THE CURRENT PATTERN...WITH SOME SLIGHT DAY-TO-DAY VARIATION...WILL
PERSIST INTO EARLY NEXT WEEK. OFFSHORE HIGH PRESSURE AND A THERMAL
TROUGH OVER NORTHERN CALIFORNIA WILL COMBINE TO MAINTAIN STEEP WIND
WAVE DOMINATED SEAS AND AREAS OF SMALL CRAFT ADVISORY WINDS INTO THE
WEEKEND...WITH THE STRONGEST WINDS AND STEEPEST SEAS FROM CAPE
BLANCO SOUTH IN THE AFTERNOONS AND EVENINGS. WINDS MAY INCREASE TO
GALES WITH VERY STEEP SEAS FRIDAY AFTERNOON FOR AREAS SOUTH OF
CAPE BLANCO. CONFIDENCE IS MODERATE ON THE GALES AND VERY STEEP
SEAS...AS MODELS CONTINUE TO POSTPONE THE PERIOD OF STRONGEST
WINDS. IN ANY CASE...THE GALES WILL BE LOW END. STOCKTON

&&

.PREV DISCUSSION... /ISSUED 326 PM PDT THU JUL 31 2014/

DISCUSSION...
MANY WILDFIRES BURNING ACROSS THE AREA ARE RESULTING IN SMOKEY
CONDITIONS IN SOME AREAS. MEANWHILE, MORE THUNDERSTORMS ARE
FORMING THIS AFTERNOON, THOUGH THEY HAVE BEEN GENERALLY LESS
NUMEROUS THAN YESTERDAY. SOME WARMING AT THE 500MB LEVEL MOVING IN
FROM THE SOUTHWEST SEEMS TO BE LIMITING VERTICAL DEVELOPMENT OF
THE CONVECTIVE CLOUDS ACROSS SISKIYOU COUNTY AND THE WEST SIDE,
THOUGH THIS MIGHT ALSO BE PARTIALLY ATTRIBUTABLE TO THE
OVERSEEDING OF THE CLOUDS FROM WILDFIRE SMOKE. THROUGH THE REST OF
THE AFTERNOON INTO THE EVENING SCATTERED SHOWERS AND THUNDERSTORMS
WILL FOCUS FROM THE CASCADES EASTWARD. LATE AFTERNOON THROUGH
EARLY EVENING THE ACTIVITY OVER SISKIYOU AND JACKSON COUNTIES MAY
BE ABLE TO OVERCOME THE MENTIONED LIMITING EFFECTS, RESULTING IN
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. AGAIN, RAINFALL WILL
BE SIGNIFICANT IN SOME AREAS, BUT LIGHTNING STARTING FIRES WILL
ALSO CONTINUE TO BE A MAJOR CONCERN. ISOLATED SMALL HAIL AND GUSTY
WINDS UP TO 40 MPH WILL BE POSSIBLE IN STRONGER CELLS.

ON FRIDAY WE EXPECT STORMS TO FOCUS OVER THE CASCADES NORTH OF
CRATER LAKE AND ACROSS NORTHERN KLAMATH AND LAKE COUNTIES. THESE
STORMS ARE EXPECTED TO BE MORE ISOLATED, SO NO WATCHES ARE
WARNINGS ARE IN EFFECT FOR THUNDERSTORMS FOR TOMORROW. ELSEWHERE
MOISTURE WILL BE LIMITED AND 500MB WARMING SHOULD KEEP A LID ON
THE VERTICAL CLOUD DEVELOPMENT.

ON SATURDAY AFTERNOON AND EVENING A SHORTWAVE TROUGH WILL MOVE
THROUGH FROM SOUTHWEST TO NORTHEAST. THIS IS LIKELY TO GIVE RISE
TO AN UPTICK IN DIURNAL THUNDERSTORM ACTIVITY, ESPECIALLY ACROSS
KLAMATH AND LAKE COUNTIES, WHERE A FIRE WEATHER WATCH FOR
ABUNDANT LIGHTNING HAS BEEN ISSUED.

SUNDAY THROUGH THE MIDDLE OF NEXT WEEK THUNDERSTORMS WILL REMAIN
IN THE FORECAST FOR MOST DAYS ON THE EAST SIDE. TEMPERATURES WILL
REMAIN ABOVE NORMAL AND A GENERAL SOUTHWEST FLOW WILL PERSIST OVER
THE AREA. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...     RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR
     ORZ617-622>625.
     FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
     EVENING FOR ORZ624-625.

CA...RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR CAZ284-285.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
     UNTIL 5 AM PDT MONDAY FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT SUNDAY FOR
     PZZ356-376.
     HAZARDOUS SEAS WARNING UNTIL 5 AM PDT MONDAY FOR PZZ356-376.
     GALE WARNING FROM 2 PM FRIDAY TO 11 PM PDT SUNDAY FOR PZZ376.

$$

MAS/BTL/JRS/CC