779  
FXUS65 KREV 222103  
AFDREV  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RENO NV  
203 PM PDT SAT SEP 22 2018  
   
SYNOPSIS
 
 
THE SIERRA AND WESTERN NEVADA WILL REMAIN DRY THROUGH NEXT WEEK  
WITH WARM AFTERNOONS AND CHILLY MORNINGS. BREEZY AFTERNOONS ARE  
FORECAST THIS WEEKEND, FOLLOWED BY SEVERAL DAYS OF LIGHTER WINDS.  
 

 
   
DISCUSSION
 
 
THE PRIMARY WEATHER FEATURE IN THE NEAR TERM IS A TROUGH OF LOW  
PRESSURE MOVING INTO THE REGION LATE TONIGHT AND SUNDAY. THIS  
TROUGH SHOULD KICK UP THE WINDS LATE THIS AFTERNOON AND THIS  
EVENING WITH AN INCREASE AGAIN SUNDAY AFTERNOON. THE STRONGEST  
WINDS ALOFT ARE PASSING THROUGH LATE TONIGHT...SO THESE MAY NOT BE  
LINED UP CORRECTLY FOR VERY STRONG SURFACE WINDS TO DEVELOP.  
THUS...WE WILL NOT BE AS CONCERNED ABOUT WIDESPREAD CRITICAL FIRE  
WEATHER CONDITIONS...ONLY LOCALIZED CRITICAL CONDITIONS. SEE THE  
FIRE WEATHER DISCUSSION BELOW FOR MORE.  
 
THE TROUGH IS QUITE DRY SO NO PRECIPITATION IS EXPECTED...JUST AN  
INCREASE IN HIGH LEVEL CLOUDS. BEHIND THE FRONT...WINDS WILL  
BEGIN TO DECREASE LATE SUNDAY AND SUNDAY NIGHT AND TEMPERATURES  
WILL DROP TO NEAR NORMAL. THE COOLEST DAY IS LIKELY TO BE MONDAY  
WITH HIGHS IN THE UPPER 70S TO LOWER 80S IN THE WESTERN NEVADA  
VALLEYS AND THE LOWER TO MID 70S FOR THE SIERRA VALLEYS.  
 
COOLER AIR ADVECTING INTO THE BASIN AND RANGE COUNTRY MONDAY NIGHT  
IS LIKELY TO INCREASE THE EAST-WEST PRESSURE GRADIENT AND CAUSE  
STRONGER EAST WINDS OVER THE SIERRA MONDAY NIGHT.  
 
TEMPERATURES BEGIN TO WARM TUESDAY...BUT THE WARMEST DAYS IN THE  
FORECAST SHOULD BE WEDNESDAY AND THURSDAY AS A RIDGE BUILDS BACK  
INTO THE REGION. HIGHS BOTH DAYS COULD CLIMB BACK TO NEAR 90 IN  
THE WESTERN NEVADA VALLEYS WITH UPPER 70S TO MID 80S IN THE SIERRA  
VALLEYS.  
 
MODEL AGREEMENT BREAKS DOWN BY FRIDAY. THE ECMWF IS FASTER  
BRINGING A LOW INTO THE PACIFIC NW...BREAKING DOWN THE RIDGE...AND  
BRINGING A LITTLE COOLING TO OUR REGION. THE GFS HOLDS THIS LOW  
OFF UNTIL SATURDAY. IT PRODUCES INCREASED WINDS BY SATURDAY AND A  
SLIGHT CHANCE OF SHOWERS IN WESTERN NEVADA BY SATURDAY EVENING. WE  
WILL LEAN TOWARD THE SLOWER GFS AT THIS POINT AS IT HAS SHOWN  
SOME RUN-TO-RUN CONSISTENCY.  
 

 
   
AVIATION
 
 
WINDS WILL INCREASE IN THE AFTERNOON TODAY AND TOMORROW, WITH GUSTS  
REACHING 20-25 KT AT AREA TERMINALS, BEFORE BECOMING LIGHT AND  
VARIABLE IN THE EVENING AND OVERNIGHT HOURS. AFTERNOON RIDGE GUSTS  
OF 35-40 KT WILL BRING THE POSSIBILITY OF TURBULENCE, ESPECIALLY FOR  
SMALLER AIRCRAFT. LLWS IS ALSO POSSIBLE SUNDAY MORNING-EARLY  
AFTERNOON AS GUSTY WINDS MOVE DOWN INTO THE VALLEYS. VFR CONDITIONS  
WILL PREVAIL FOR THE NEXT SEVERAL DAYS. CL/MLF  
 

 
   
FIRE WEATHER
 
 
WE WILL CONTINUE TO HEADLINE THE DRY AND BREEZY CONDITIONS THROUGH  
SUNDAY. WHILE CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED TO  
REMAIN ISOLATED WITH SHORT DURATION, FIRE WEATHER CONCERNS WILL BE  
ELEVATED AND ANY NEW FIRE STARTS COULD STILL SPREAD QUICKLY  
DURING THE PEAK WIND PERIODS THIS WEEKEND FROM MID-AFTERNOON TO  
EARLY EVENING.  
 
AREAS MOST LIKELY TO SEE SHORT PERIODS OF WIND GUSTS 30-35 MPH  
COMBINED WITH MINIMUM RH BETWEEN 8-16% WILL BE OVER NORTHWEST NV  
AND PARTS OF THE SIERRA FRONT THIS AFTERNOON AND EVENING (FIRE  
ZONES NORTHERN 450, WESTERN 453, AND 458). ON SUNDAY, THIS AREA  
WILL SHIFT A LITTLE FARTHER SOUTH INTO MORE OF THE SIERRA FRONT  
AND PARTS OF WEST CENTRAL NV (FIRE ZONES 450 AND 453). THE  
STRONGEST UPPER LEVEL AND RIDGETOP WINDS ARE STILL EXPECTED LATE  
TONIGHT INTO SUNDAY MORNING (WITH LIMITED RH RECOVERY), FOLLOWED  
BY DECREASING WINDS THROUGH THE DAY AS THE TROUGH SWINGS  
SOUTHEAST. THIS WOULD MOST LIKELY RESULT IN A SHORTER PERIOD OF  
WIND GUSTS EXCEEDING 30 MPH FOR LOWER ELEVATIONS, ALTHOUGH THESE  
WINDS WILL LIKELY MIX DOWN EARLIER IN THE AFTERNOON COMPARED TO  
TODAY. SOME COOLING AND PRESENCE OF CLOUD COVER SUNDAY COULD ALSO  
LIMIT THE DURATION OF THE LOWEST HUMIDITY DURING THE DAY,  
ESPECIALLY FOR PORTIONS OF THE SIERRA FRONT AND AREAS NORTH OF  
I-80. MJD  
 

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

 
 

 
 
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...  
HTTP://WEATHER.GOV/RENO  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab NV Page
The Nexlab CA Page Main Text Page