Weather Service Report


643 
FXUS65 KREV 152237 AAA
AFDREV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
333 PM PDT MON SEP 15 2014

.UPDATE...

BASED ON RADAR TRENDS WE'VE ADDED ISOLATED THUNDERSTORMS FOR OUR 
GREAT BASIN ZONES THROUGH EARLY EVENING, INCLUDING PYRAMID LAKE, 
FALLON, LOVELOCK, AND GERLACH. SOME RECENT CELLS HAVE HIT 40-50 DBZ 
WITH LIGHTNING. WE SHOULD SEE THESE STORMS DECREASE IN COVERAGE 
AFTER SUNDOWN. OTHERWISE - WINDS HAVE SWITCHED TO THE SW AND 
INCREASED ALLOWING SMOKE TO POUR INTO THE RENO AREA. WE SHOULD SEE 
SIMILAR CONDITIONS TO YESTERDAY. CS

&&

.SYNOPSIS...
SMOKE AND HAZE FROM THE KING FIRE WILL IMPACT THE NORTHERN SIERRA
AND NORTHWEST NEVADA INTO TUESDAY. LOW PRESSURE OFF THE CALIFORNIA
COAST WILL MOVE INLAND BY THURSDAY. THIS WILL PRODUCE BREEZY WINDS
WITH A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS. HIGH PRESSURE
SHOULD RETURN BY THE WEEKEND FOR WARM AND DRY CONDITIONS. 

&&

.SHORT TERM...

NOT MUCH HAS CHANGED IN THE MODEL DATA WITH SOUTH TO SOUTHWEST
FLOW ALOFT AHEAD OF A BROAD TROUGH OVER THE CENTRAL PACIFIC. ONE
SYSTEM WITHIN THE TROUGH IS TRACKING NORTH ALONG THE OREGON COAST,
WITH A SECOND LOW DEVELOPING NEAR 35N 140W. THE SECOND LOW IS THE
SYSTEM FORECAST TO MOVE ONSHORE WEDNESDAY NIGHT AND THURSDAY.

FOR THE KING FIRE, SMOKE AND HAZE WILL CONTINUE TO MOVE ACROSS THE
NORTHERN SIERRA AND INTO NORTHWEST NEVADA. THE AMOUNT OF SMOKE IS
DEPENDENT ON FIRE ACTIVITY AND WINDS. THE CURRENT SOUTH-SOUTHWEST
FLOW IS DIRECTING THE MAIN PLUME TOWARD NEVADA, SIERRA AND PLUMAS
COUNTIES. AFTERNOON WEST TO SOUTHWEST WINDS MAY BRING SOME SMOKE
INTO RENO-TAHOE, BUT NOT AS MUCH AS YESTERDAY EVENING. HAZE WILL
CONTINUE TO LINGER ACROSS WESTERN NEVADA FROM NORTHERN WASHOE
COUNTY TO PERSHING/CHURCHILL COUNTIES. AS THE LOW APPROACHES
WEDNESDAY, WINDS MAY SHIFT TOWARD THE SOUTHWEST AND DIRECT THE
MAIN PLUME CLOSER TO THE NORTH SIDE OF LAKE TAHOE AND RENO. THE
INCOMING LOW WILL INCREASE THE SURFACE HUMIDITY ALONG THE WESTERN
SIERRA SLOPES, WHICH SHOULD HELP DECREASE FIRE ACTIVITY. 

FARTHER SOUTH SMOKE AND HAZE FROM THE MEADOW AND COURTNEY FIRES
HAS WORKED ITS WAY BACK INTO MONO COUNTY. BASED ON WINDS AND FIRE
ACTIVITY SOME REDUCED VISIBILITY SHOULD CONTINUE INTO WEDNESDAY.

SURFACE GUSTS WILL INCREASE EACH DAY THROUGH WEDNESDAY. PEAK GUSTS
TODAY WILL BE NEAR AND BELOW 30 MPH, BY WEDNESDAY PEAK GUSTS
SHOULD REACH 40 MPH. WIND PRONE LOCATIONS ALONG HIGHWAY 395 FROM
LASSEN COUNTY TO THE EASTERN SIERRA COULD REACH 45 MPH. THE SOUTH-
SOUTHWEST FLOW ALOFT MAY PRODUCE 20-30 MPH SUSTAINED WINDS AT THE
RENO AIRPORT ON WEDNESDAY. MAIN IMPACTS FROM WINDS ARE TO BOATERS
ON AREA LAKES, ESPECIALLY TAHOE, AND TO FIRE WEATHER. THINK THE
FIRE THREAT WILL BE MINIMIZED DUE TO AFTERNOON HUMIDITY NEAR AND
ABOVE 15%.

A FEW SHOWERS AND THUNDERSTORMS MAY DEVELOP LATE THIS AFTERNOON
OVER MONO-MINERAL COUNTIES AND LASSEN-NORTHERN WASHOE COUNTIES.
ADDITIONAL MOISTURE WILL ARRIVE WEDNESDAY FROM THE LOW NEAR 35N
140W, TO PRODUCE A SLIGHT CHANCE OF SHOWERS FOR MID WEEK. NO
MOISTURE FROM ODILE WILL REACH THE EASTERN SIERRA AND WESTERN
NEVADA. LATEST FORECAST FROM HURRICANE CENTER SHOWS THE SYSTEM
BEING DEFLECTED TO THE EAST WITH MOST OF THE MOISTURE IMPACTING
SOUTHERN NEVADA, ARIZONA AND NORTHERN MEXICO. BRONG

.LONG TERM...THURSDAY THROUGH SUNDAY...

ANOTHER ROUND OF ADJUSTMENTS FOR THE LONG-TERM FORECAST. MODELS 
CONTINUE TO DIFFER GREATLY, BUT THE GFS IS TRENDING MORE LIKE THE 
ECMWF DEPICTING A MEANDERING CUT-OFF LOW AFTER THE INITIAL WAVE 
PUSHING THROUGH ON THURSDAY. OVERALL, THE FORECAST IS RATHER LOW  
CONFIDENCE WHICH IS TYPICAL WHEN CONSIDERING A CUT-OFF TYPE SYSTEM 
AND LARGE VARIANCES BETWEEN MODEL SOLUTIONS. 

THE GFS/EC ARE NOW SHOWING AN UPPER TROUGH DROPPING INTO SOUTHERN 
CALIFORNIA RATHER THAN HANGING AROUND THE CENTRAL PORTION OF THE 
STATE WHILE CUTTING OFF THE UPPER LOW FROM UPPER LEVEL FLOW. 
MOMENTUM CARRIES THE UPPER LOW FARTHER SOUTH TOWARDS THE 
ARIZONA/NEVADA/CALIFORNIA TRIPLE POINT. THIS MORE SOUTHERN 
DISPLACEMENT COMBINED WITH A CONSENSUS THAT MONSOONAL MOISTURE WILL 
REMAIN WELL SOUTH AND EAST OF THE FORECAST AREA HAS LED TO THE 
TRIMMING BACK OF PRECIPITATION CHANCES FROM FRIDAY ONWARD. THESE 
CHANCES ARE NOW MAINLY LIMITED TO THE SIERRA SOUTH OF THE TAHOE 
BASIN AND SOUTHERN MONO COUNTY. OPTED NOT TO TRIM BACK ON THURSDAY 
WITH THE MAIN WAVE APPROACHING, BUT GFS/EC ARE BEGINNING TO TREND 
DRIER AS ODILE STAGNATES OFF THE BAJA PENINSULA. MAY NEED TO LOWER 
CHANCES FOR MINERAL COUNTY AND EASTERN MONO COUNTY IF THIS TREND 
CONTINUES DUE TO THE SPLIT NATURE OF THE APPROACHING WAVE AND 
POTENTIAL FOR DRIER CONDITIONS. 

OTHERWISE, HAVE TRENDED AFTERNOON RELATIVE HUMIDITY DOWN IN THE 
GREAT BASIN DUE TO DRIER MODEL DEPICTIONS IN DETERMINISTIC AND 
ENSEMBLE SOLUTIONS. SUBSEQUENTLY, WARMED TEMPERATURES AS WELL BACK 
INTO THE UPPER 80S BY THE WEEKEND WHICH IS A FEW DEGREES ABOVE 
SEASONAL AVERAGES. BOYD

&&

.AVIATION...

SMOKE FROM THE KING FIRE WILL BE A THREAT AGAIN THIS AFTERNOON AND 
EVENING MAINLY FOR TERMINALS FROM KTVL NORTHWARD IN THE SIERRA. 
WINDS WILL SHIFT SOUTHWESTERLY AND SMOKE WILL MOSTLY AFFECT KTRK 
DEGRADING VISIBILITY TO MVFR. SOME SMOKE MAY FILTER INTO KTVL AND 
KRNO, BUT THESE LOCATIONS SHOULD REMAIN VFR. 

WINDS WILL BE BREEZY AGAIN THIS AFTERNOON THROUGH WEDNESDAY AS 
SOUTHWESTERLY FLOW DEEPENS/STRENGTHENS DUE TO AN APPROACHING 
SHORTWAVE. THERE WILL BE SOME THREAT OF SHOWERS AND THUNDERSTORMS 
FOR ALL TERMINALS EXCEPT KNFL AND KLOL WHICH SHOULD REMAIN DRY. THE 
BEST CHANCES OF A SHOWER/THUNDERSTORM WILL BE MAINLY ON THURSDAY. 
BOYD 

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&

$$

FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)







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