Area Forecast Discussion
Issued by NWS Reno, NV

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FXUS65 KREV 031125
AFDREV

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE RENO NV
425 AM PDT THU SEP 3 2015

UPDATED TO INCLUDE FIRE WEATHER DISCUSSION AND RAISE FIRE WEATHER
WATCH FRIDAY

.SYNOPSIS...

BREEZY CONDITIONS WILL CONTINUE THROUGH THE REMAINDER OF THE WORK
WEEK WITH THE STRONGEST WINDS EXPECTED ON FRIDAY AFTERNOON AND
EVENING. THIS WILL RESULT IN HAZARDOUS BOATING CONDITIONS, AREAS
OF BLOWING DUST, AND PERIODS OF NEAR CRITICAL FIRE WEATHER
CONDITIONS. A COLD FRONT WILL PUSH THROUGH NORTHEAST CALIFORNIA
AND NORTHWEST NEVADA FRIDAY, BRINGING WELL BELOW NORMAL
TEMPERATURES TO START THE HOLIDAY WEEKEND.

&&

.SHORT TERM...

THE GREATEST CONCERN OVER THE NEXT FEW DAYS REMAINS AN AREA OF LOW
PRESSURE AND ASSOCIATED COLD FRONT MOVING ACROSS NORTHEAST
CALIFORNIA AND NORTHWEST NEVADA. THIS SYSTEM WILL BRING WINDY
CONDITIONS TO THE AREA TODAY INTO FRIDAY, RESULTING IN HAZARDOUS
BOATING CONDITIONS, TURBULENCE FOR AVIATION, AREAS OF BLOWING
DUST DOWNWIND OF DESERTS AND SINKS, AND PERIODS OF NEAR CRITICAL
FIRE WEATHER CONDITIONS. WHILE WINDS WILL BE BREEZY TODAY, THE
THERMAL GRADIENT AND JET MAX WILL PEAK ON FRIDAY, MAKING THAT
AFTERNOON AND EVENING THE BEST BET FOR THE STRONGEST WINDS WITH
GUSTS IN THE 35 TO 45 MPH RANGE. FOR THOSE AT THE BURNING MAN
FESTIVAL IN BLACK ROCK CITY - VISIBILITY MAY DROP BELOW A MILE IN
BLOWING DUST ON THE PLAYA FRIDAY AND LOOSE OBJECTS COULD BECOME
AIRBORNE, BECOMING A DANGER FOR FESTIVAL GOERS.

AS THE CORE OF THE LOW DIGS SOUTH, THERE WILL BE CHANCES FOR
SHOWERS NEAR THE OREGON BORDER FRIDAY INTO SATURDAY. THERE IS
MARGINAL FORCING FRIDAY, WHICH MAY PRODUCE SOME EMBEDDED
THUNDERSTORMS AS WELL. HAVE PULLED PRECIPITATION CHANCES NORTHWARD
ON SATURDAY AS A SIGNIFICANT DRY LAYER MOVES INTO THE MIDLEVELS,
STABILIZING THE ATMOSPHERE. PRECIPITATION AMOUNTS WILL GENERALLY
BE LIGHT, UNDER A TENTH OF AN INCH, WITH THE BEST CHANCES NORTH OF
A PORTOLA-PYRAMID LAKE-LOVELOCK LINE, WHICH DOES INCLUDE BLACK
ROCK CITY.

THE OTHER MAJOR IMPACT FROM THIS LOW WILL BE SIGNIFICANTLY COLDER
TEMPERATURES. HIGHS ARE ONLY EXPECTED TO BE IN THE MID 60S TO MID
70S IN WESTERN NEVADA VALLEYS TO START THE WEEKEND WITH UPPER 50S
TO LOW 60S IN SIERRA VALLEYS. OVERNIGHT LOWS WILL BE QUITE COOL AS
WELL, WITH THE COLDEST MORNING ON SUNDAY AS SKIES CLEAR AND WINDS
BECOME LIGHT. THOSE IN COLDER WESTERN NEVADA VALLEYS SHOULD
PREPARE FOR TEMPERATURES DIPPING TO NEAR FREEZING, WHILE SIERRA
VALLEYS WILL LIKELY BE IN THE MID 20S. COVER SENSITIVE VEGETATION
AND BE SURE TO BE PREPARED FOR MUCH COLDER TEMPERATURES IF YOU
HAVE OUTDOOR PLANS FRIDAY-SUNDAY MORNING. DJ

.LONG TERM...

AS UPPER LOW LIFTS NORTHEAST AWAY FROM AREA, TEMPERATURES WILL
BEGIN TO REBOUND FOR THE REST OF THE HOLIDAY WEEKEND. THE AIRMASS
IS STILL QUITE DRY AND THEREFORE NIGHTTIME LOWS WILL SEE A SLOWER
RECOVERY AND REMAIN QUITE COOL. MOST MEDIUM RANGE MODELS INDICATE
A SECONDARY SHORTWAVE DROPPING SOUTHEASTWARD MONDAY NIGHT INTO
TUESDAY ALTHOUGH THERE IS VARIABILITY IN STRENGTH AMONG THOSE
SOLUTIONS. BOTH SCENARIOS WOULD BE DRY WITH THE ONLY QUESTION
BEING WHETHER THERE WOULD BE ANY COOLING OR IF THE WARMUP WOULD BE
SLOWED FOR TUESDAY. WE PULLED BACK TEMPS SLIGHTLY, BUT OVERALL, IT
SHOULD STILL BE A WARM END TO THE HOLIDAY WEEKEND GOING INTO THE
MIDDLE OF NEXT WEEK. GIVEN THIS SECOND WAVE, THE ATMOSPHERE WILL
BE TOO DRY FOR ANY CONVECTION AND WE PULLED EVEN THE GHOST POPS IN
THE SIERRA FOR MID NEXT WEEK. HOHMANN

&&

.AVIATION...

LOW PRESSURE SYSTEM WILL CONTINUE TO BRING GUSTY AFTERNOON WINDS
THROUGH FRIDAY WITH STRONGEST WINDS ON FRIDAY AS TROUGH AND COLD
FRONT WORK INTO THE AREA FROM THE NORTH. GUSTS TODAY SHOULD REMAIN
IN THE 20-25KT RANGE, INCREASING TO 25-30KT WITH LOCALLY HIGHER
GUSTS FRIDAY. RIDGE GUSTS WILL REACH AROUND 50KT BY FRIDAY WHICH
WILL LIKELY BRING LEE SIDE TURBULENCE. IN ADDITION, VISIBILITY
WILL DROP TO ONE MILE AT TIMES IN BLOWING DUST DOWNWIND OF DRY
SINKS AND LAKE BEDS FRIDAY.

THE LOW DROPS SOUTHWARD ON FRIDAY ALLOWING FOR ENOUGH MOISTURE,
INSTABILITY AND FRONTAL FORCING TO WARRANT A SLIGHT CHANCE OF
THUNDERSTORMS ACROSS FAR NORTHEAST CA AND NORTHWEST NV (GENERALLY
NORTH OF A SUSANVILLE TO GERLACH LINE). COVERAGE OF STORMS SHOULD
BE LOW WITH MOSTLY SHOWERS. AS THE LOW MOVES EAST ON SATURDAY
SHOWERS ACROSS NORTHERN NV WILL GRADUALLY END FROM WEST TO EAST.
HOHMANN

&&

.FIRE WEATHER...

TODAY, IT WILL BE BREEZY AGAIN (25-30 MPH, LOCALLY 35 MPH) IN THE
AFTERNOON AS A COLD FRONT HANGS UP OVER NORTHERN CALIFORNIA AND
NORTHWEST NEVADA. HOWEVER, COMPARED TO WEDNESDAY AFTERNOON, WINDS
WILL BE A BIT LESS OVERALL WITH COOLER TEMPERATURES AND SLIGHTLY
HIGHER HUMIDITY. SO CONDITIONS ARE EXPECTED TO REMAIN MOSTLY SUB
CRITICAL TODAY.

FRIDAY, MODELS CONTINUE TO INDICATE A PRONOUNCED DRY SLOT PUSHING
INTO AREAS SOUTH OF I-80 ABOVE ABOUT 650-700 MB (10,000-11,000 FT
MSL). LATEST 06Z MODEL SOUNDINGS SUGGEST MIXING WILL BE DEEP ENOUGH
BY EARLY AFTERNOON TO BEGIN TAPPING THIS DRIER AIR WITH MOS GUIDANCE
INDICATING FALLING DEWPOINTS DURING THE AFTERNOON AND EARLY EVENING.
BASED ON CURRENT FORECAST TEMPERATURES, CRITICAL FIRE WEATHER
CONDITIONS MAY BE MET FOR LOWER ELEVATIONS SOUTH OF I-80 WITH THE
MOST PROLONGED CONDITIONS ACROSS THE BASIN AND RANGE DOWN INTO
NORTHERN AND WESTERN MINERAL COUNTY AS WELL AS SOUTHERN LYON COUNTY.
WINDS WILL BE STRONGEST ALONG THE SIERRA FRONT WHERE GUSTS 40-45 MPH
WILL BE POSSIBLE. HOWEVER, IT MAY BE TOO COOL BY THE TIME THE DRIER
AIR MIXES DOWN TO REALIZE A SUFFICIENT PERIOD OF CRITICAL
CONDITIONS. WE WILL GO AHEAD AND HOIST A FIRE WEATHER WATCH FRIDAY
AFTERNOON FOR WESTERN NV AND FINE TUNE ANY DETAILS LATER TODAY.
HOHMANN

&&


.REV WATCHES/WARNINGS/ADVISORIES...
NV...FIRE WEATHER WATCH FROM FRIDAY AFTERNOON THROUGH FRIDAY EVENING
     NVZ450-453-459.

CA...NONE.

&&

$$

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


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