Red Flag Warning 18, NWS Medford, OR

347 
WWUS86 KMFR 142140
RFWMFR

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE MEDFORD OR
240 PM PDT FRI SEP 14 2012

CAZ284-285-151300-
/O.UPG.KMFR.FW.A.0017.120915T2100Z-120916T0400Z/
/O.NEW.KMFR.FW.W.0019.120915T2100Z-120916T0400Z/
/O.CON.KMFR.FW.W.0018.000000T0000Z-120915T0400Z/
SISKIYOU COUNTY FROM THE CASCADE MOUNTAINS EAST AND SOUTH TO MT
SHASTA-MODOC COUNTY EXCEPT FOR THE SURPRISE VALLEY-
240 PM PDT FRI SEP 14 2012

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT THIS EVENING
   FOR COMBINATION OF STRONG WINDS AND LOW RELATIVE HUMIDITIES FOR
   FIRE ZONES 284 AND 285...
...RED FLAG WARNING IN EFFECT FROM 2 PM TO 9 PM PDT SATURDAY FOR
   COMBINATION OF STRONG WINDS AND LOW RELATIVE HUMIDITIES FOR 
   FIRE ZONES 284 AND 285...

THE NATIONAL WEATHER SERVICE IN MEDFORD HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT FROM 2 PM TO 9 PM PDT SATURDAY. THE
FIRE WEATHER WATCH IS NO LONGER IN EFFECT. 

* AFFECTED AREA: FIRE ZONES 285 AND EASTERN 284.

* WIND...SOUTHWEST WINDS 10 TO 15 MPH WITH GUSTS TO 25 MPH.

* HUMIDITY...MINIMUM HUMIDITIES OF 7 TO 12 PERCENT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. THESE CONDITIONS WILL
CREATE THE POTENTIAL FOR EXPLOSIVE FIRE GROWTH.

&&

$$

VISIT US AT WWW.WEATHER.GOV/MEDFORD

STOCKTON

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
205 AM PDT FRI SEP 14 2012

.DISCUSSION...A LARGE, STRONG RIDGE OF HIGH PRESSURE REMAINS
CENTERED OVER THE ROCKY MOUNTAINS. SOME MID-LEVEL MOISTURE HAS
ROTATED UP FROM THE SOUTHWEST BUT THE LOWER LEVELS OF THE
ATMOSPHERE WILL REMAIN VERY DRY. THE EXCEPTION IS THE COASTAL
AREAS. THE STRONG RIDGE HAS COMPRESSED THE MARINE LAYER MAKING IT
RATHER SHALLOW BUT TAKING THE CLOUD DECK DOWN TO THE SURFACE AS
FOG. A WEAK LOW PRESSURE TROUGH WILL APPROACH THE PACIFIC
NORTHWEST COAST TODAY. VERY LITTLE MOISTURE IS ASSOCIATED WITH THE
TROUGH SO NO PRECIPITATION IS EXPECTED BUT IT WILL SUPRESS THE
ROCKY MOUNTAIN HIGH PRESSURE RIDGE. THE MAIN EFFECT WILL BE A
MODERATION OF TEMPERATURES. AFTERNOON HIGHS WILL CONTINUE TO RUN
BETWEEN 5 AND 10 DEGREES ABOVE NORMAL BUT SHOULD NOT APPROACH
RECORD LEVELS. THE TROUGH WILL ALSO ALLOW THE MARINE LAYER TO
DEEPEN LIFTING MOST OF THE COASTAL FOG BUT ALSO BRINGING MORNING
CLOUDS TO THE UMPQUA BASIN BEGINNING SATURDAY MORNING.

AS THE TROUGH MOVES INTO THE PACIFIC NORTHWEST SATURDAY A SECOND
RIDGE OF HIGH PRESSURE BUILDS OVER THE EASTERN PACIFIC NEAR 140W.
THE BUILDING RIDGE CAUSES THE TROUGH TO STALL OVER THE AREA. ALL
THE FORECAST MODEL GUIDANCE IS IN REMARKABLE AGREEMENT WITH THIS
SOLUTION SO CONFIDENCE IS VERY HIGH. THE MODELS ALSO AGREE ON THE
DEVELOPMENT OF A WEAK LOW PRESSURE AREA UNDER THE RIDGE AROUND 35N
135W. THE MODELS DO BEGIN TO DIFFER WITH WHAT TO DO WITH THE LOW.
IF IT REMAINS BEYOND 130W THERE WILL BE LITTLE EFFECT ON OUR
WEATHER. BUT IF IT MOVES CLOSER TO THE COAST SOME MOISTURE COULD
BE DRAWN UP FROM THE SOUTHWEST. THIS WOULD OCCUR NEXT THURSDAY.
THE FORECAST CONTINUES TO BE DRY FOR ALL AREAS AWAY FROM THE COAST
BUT WHERE THIS LOW GOES IS NOT DEFINITE.

&&

.AVIATION...THE LOW LEVEL STRATUS AND FOG CONTINUES TO SURGE
NORTHWARD. CEILINGS AND VISIBILITY WILL REMAIN AT IFR TO LIFR
UNTIL MID MORNING. THE ONSHORE PUSH WILL NOT BE STRONG ENOUGH OR
DEEP ENOUGH TO MAKE IT OVER THE COASTAL MOUNTAINS, SO ALL OTHER
TERMINALS WILL REMAIN VFR THROUGH THE DAY.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PZ...NONE.

LOVEGROVE