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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
616 AM PDT FRI MAR 27 2015

.UPDATE...
JUST A MINOR UPDATE THIS MORNING TO ADD AREAS OF FREEZING FOG
AROUND TRUCKEE. THE FOG DOES NOT SEEM TO BE AS WIDESPREAD AS A
COUPLE OF MORNINGS AGO...BUT WILL STILL REDUCE THE VISIBILITY
ALONG HIGHWAY 267 NEAR THE TRUCKEE AIRPORT AND IN PORTIONS OF THE
CITY OF TRUCKEE THROUGH 8-9 AM. 20

&&

.PREVIOUS DISCUSSION... /ISSUED 311 AM PDT FRI MAR 27 2015/ 

SYNOPSIS...
BREEZY, WARM AND DRY CONDITIONS ARE ON TAP FOR THIS AFTERNOON
ACROSS NORTHEAST CALIFORNIA AND WESTERN NEVADA AS LOW PRESSURE
APPROACHES THE PACIFIC NORTHWEST COAST. THE WEAK LOW PRESSURE WILL
BRING SLIGHTLY COOLER TEMPERATURES FOR THE WEEKEND INTO EARLY NEXT
WEEK ALTHOUGH HIGHS WILL REMAIN WELL ABOVE NORMAL.

SHORT TERM...
THE MAIN SHORT TERM FORECAST CHANGES INCLUDE INCREASING WINDS
SLIGHTLY FOR MANY AREAS TONIGHT AND NARROWING DOWN TIMING FOR
ISOLATED SHOWERS NEAR THE ALPINE/MONO COUNTY CREST OVER THE
WEEKEND.

THE ABSURDLY WARM CONDITIONS CONTINUE TODAY UNDER A STRONG HIGH
PRESSURE RIDGE, WITH SOME DAILY HIGH TEMPERATURE RECORDS LIKELY 
TO FALL. THIS AFTERNOON AND EVENING, AN UPPER TROUGH WILL BE
APPROACHING THE PACIFIC NORTHWEST COAST AS THE RIDGE BEGINS TO
SHIFT INTO EASTERN NEVADA AND UTAH. THE RESULTANT INCREASE IN THE
THERMAL GRADIENT IS EXPECTED TO BRING WINDS OF 10-20 MPH WITH GUSTS
30-35 MPH, ESPECIALLY NORTH OF HIGHWAY 50 INTO FAR WESTERN NEVADA.

FOR TONIGHT, WEAK LOW PRESSURE WILL MOVE THROUGH OREGON AND
WASHINGTON. WITH 700 MB WINDS PICKING UP TO BETWEEN 30-40 KTS NORTH
OF HIGHWAY 50 OVERNIGHT, THE ATMOSPHERE MAY STAY A BIT MIXED UP
WITH WINDS REMAINING ELEVATED FOR MID SLOPES AND RIDGES. AS FAR AS
PRECIPITATION, A FEW LIGHT SHOWERS ARE STILL POSSIBLE NORTH OF
SUSANVILLE AND GERLACH LATE TONIGHT AND EARLY SATURDAY AS A SURFACE
FRONT BRIEFLY LINES UP WITH WEAK FORCING AT THE TAIL END OF THE
OREGON/WASHINGTON TROUGH.

SATURDAY, A MILD PACIFIC HIGH BUILDS INTO NEVADA AND NORTHEAST
CALIFORNIA. LIGHT NORTHEAST LOW LEVEL FLOW AND LOWER TEMPERATURES
ALOFT WILL BRING SLIGHTLY COOLER TEMPERATURES. I HAVE LEFT THE
SLIGHT CHANCE FOR SHOWERS NEAR THE SIERRA CREST SOUTH OF HIGHWAY
50 FOR A FEW HOURS SATURDAY EVENING FOR CONSISTENCY SAKE. HOWEVER,
ONLY THE GFS SHOWS ANY HINT OF PRECIPITATION SO IT MAY WIND UP JUST
BEING SCATTERED CUMULUS.

ON SUNDAY, WELL ABOVE AVERAGE SURFACE TEMPERATURES AND FAIRLY COOL
TEMPERATURES IN THE MID LEVELS MAY ALLOW FOR A BETTER SHOT AT A
FEW DIURNALLY-LINKED SHOWERS NEAR THE CREST OF MONO COUNTY.
INSTABILITY LOOKS MEEK SO THUNDERSTORM CHANCES LOOKS REMOTE AT
THIS TIME. SNYDER

LONG TERM...MONDAY THROUGH THURSDAY...
MEDIUM RANGE MODELS ARE STARTING TO SHOW BETTER AGREEMENT WITH 
REGARD TO A SERIES OF WAVES MOVING OVER THE THE TOP OF A FLAT RIDGE 
DURING THE EXTENDED PERIOD. MINOR CHANGES WERE MADE TO TREND TOWARD 
A SLIGHTLY WETTER SOLUTION BY THE END OF THE PERIOD AS CONFIDENCE 
BEGINS TO INCREASE.

SHORT WAVE RIDGE FOR MONDAY SLIDES EAST AS A WAVE MOVES TOWARD THE 
WEST COAST. MONDAY SHOULD BE THE WARMEST DAY OF THE EXTENDED WITH 
HIGH TEMPS 10-15 DEGREES ABOVE AVERAGE. WINDS INCREASE MONDAY EVENING 
AHEAD OF THIS SHORT WAVE SO OVERNIGHT LOWS WILL STAY MILD THROUGH 
TUESDAY MORNING. 

THE PASSAGE OF THIS FIRST WAVE TO THE NORTH OF THE CWA WILL DO 
LITTLE MORE THAN LOWER HIGH TEMPS 8-10 DEGREES FOR TUESDAY...
ALTHOUGH THAT IS STILL ABOVE AVERAGE. A WEAK SECONDARY WAVE PUSHES 
ACROSS EARLY WEDNESDAY AND KEEP THESE TEMPS DOWN A BIT.

MODELS HAVE NOW CONVERGED ON A STRONGER WAVE THAT DIVES EAST 
SOUTHEAST INTO THE GREAT BASIN ON THURSDAY. THIS BRINGS MUCH COLDER
AIR INTO FAR NORTHERN AND NORTHEAST NEVADA WITH NORTHWEST AND
CENTRAL NEVADA ON THE FRINGE OF THIS COLDER AIR. THIS WAVE IS ALSO
A BIT MORE DYNAMIC WITH ENOUGH FORCING TO PRODUCE SHOWERS OVER THE
FAR NORTHERN AND NORTHEAST CWA THURSDAY AFTERNOON AND EVENING.
SLIGHT CHANCE POPS WERE ADDED NORTH AND WEST OF A BIEBER TO GERLACH
TO LOVELOCK TO AUSTIN LINE FOR THURSDAY. 20

AVIATION...
RIDGE OVERHEAD THIS MORNING BEGINS TO SHIFT EAST AS A TROUGH OF LOW 
PRESSURE MOVES ACROSS THE NORTHERN PART OF THE FORECAST AREA TONIGHT 
INTO SATURDAY. VFR CONDITIONS SHOULD PERSIST TODAY FOR ALL BUT THE 
EARLY MORNING HOURS IN FAVORED FOG PRONE SIERRA VALLEYS WHERE SHALLOW
FOG WILL CREATE OCCASIONAL IFR CONDITIONS.

SFC AND RIDGE WINDS BEGIN TO INCREASE THIS AFTERNOON AHEAD OF THE 
TROUGH OF LOW PRESSURE WITH SFC GUSTS OF 25-30 KTS NORTH OF HIGHWAY 
50 AND WEST OF HIGHWAY 95. RIDGE GUSTS COULD REACH 50 KTS BY EARLY 
EVENING WITH TURBULENCE LIKELY OVER AND EAST OF THE SIERRA AND HIGHER 
RANGES IN FAR NORTHEAST CALIFORNIA AND WESTERN NEVADA.

ISOLATED SHOWERS ARE POSSIBLE OVER THE FAR NORTHERN PART OF THE 
FORECAST AREA LATE TONIGHT...NORTH OF SUSANVILLE...WITH A FEW ISOLATED
SHOWERS IN THE SIERRA SOUTH OF TAHOE FOR SATURDAY EVENING. THESE
SHOWERS COULD BRIEFLY REDUCE CIGS/VSBYS TO MVFR OR LESS. MORE
SHOWERS ARE POSSIBLE FOR THE SIERRA IN MONO COUNTY ON SUNDAY. 20

&&

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

$$

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