960
FXUS65 KREV 102147
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
247 PM PDT SAT OCT 10 2026
KEY MESSAGES
* CRITICAL FIRE WEATHER AND HAZARDOUS LAKE CONDITIONS CONTINUE
THROUGH THIS EVENING DUE TO STRONG SOUTHWEST WINDS.
* MUCH COLDER TEMPERATURES ALONG WITH RAIN AND MOUNTAIN SNOW SHOWER
CHANCES BEGIN NEXT WEEK IN THE WAKE OF A COLD FRONT PASSAGE.
* MOISTURE ASSOCIATED WITH TROPICAL STORM RACHEL WILL BOOST SHOWER
CHANCES SUNDAY AND MONDAY.
DISCUSSION
ACCORDING TO THE LATEST SURFACE OBSERVATIONS, A COLD FRONT,
ASSOCIATED WITH AN UPPER TROUGH OVER THE WESTERN CONUS, HAS CROSSED
INTO NE CALIFORNIA AND FAR NW NEVADA THIS AFTERNOON. AHEAD OF THIS
FRONTAL PASSAGE, WINDS THROUGH THIS EVENING WILL GUST UP TO AROUND
35-45 MPH IN THE LOWER VALLEYS WHILE THE SIERRA RIDGES WILL GUST UP
TO AROUND 70-80 MPH GOING THROUGH THE OVERNIGHT HOURS. THESE WINDS
IN CONJUNCTION WITH LOW RELATIVE HUMIDITY VALUES (~15-25%) WILL
ALLOW FOR CRITICAL FIRE WEATHER CONCERNS THROUGH THIS EVENING IN
PORTIONS OF THE EASTERN SIERRA AS WELL AS W.NEVADA (SEE THE RED FLAG
WARNING CURRENTLY IN EFFECT AND THE FIRE WEATHER SECTION FOR MORE
DETAILS). THESE INCREASED WINDS WILL CAUSE CHOPPY CONDITIONS ON AREA
LAKES TODAY (REFER TO THE ONGOING LAKE WIND ADVISORY FOR MORE
DETAILS), SO PLEASE KEEP THIS IN MIND IF YOU HAVE OUTDOOR
RECREATIONAL PLANS. BLOWING DUST IS ALSO POSSIBLE NEAR DESERT SINKS
AND PLAYAS TODAY. BE PREPARED FOR A COLDER NIGHT AS THE FORECAST
CALLS FOR OVERNIGHT LOWS AROUND THE 40 DEGREE MARK IN W.NEVADA WITH
SIERRA COMMUNITIES NEAR OR SLIGHTLY BELOW THE FREEZING MARK.
FOR SUNDAY, FORECAST GUIDANCE SHOWS THE UPPER TROUGH PROGRESSING
EASTWARD AND CONTINUING THE TREND TOWARD COOLER TEMPERATURES BEHIND
THE COLD FRONT PASSAGE. W.NEVADA VALLEYS WILL HAVE HIGHS IN THE LOW
TO MID-60S WITH SIERRA COMMUNITIES IN THE MID-50S TO AROUND THE 60
DEGREE MARK. FORECAST GUIDANCE ALSO SHOWS TROPICAL STORM RACHEL
MAKING ITS WAY ACROSS SE CALIFORNIA EARLY SUNDAY, WHICH WILL ALLOW
FOR 15-25% SHOWER CHANCES WITHIN THE REGION IN THE MORNING THAT
INCREASE UP TO 30-50% BY SUNDAY AFTERNOON. BY LATE SUNDAY AND GOING
THROUGH MONDAY, SHOWER CHANCES INCREASE TO 60-80% ESPECIALLY FOR
AREAS ALONG AND SOUTH OF I-80 AS THE CORE OF THE SYSTEM PASSES WELL
OFF TO EAST. THE LATEST QPF VALUES THROUGH SUNDAY AND MONDAY
RANGE FROM A TRACE TO AROUND 0.5 INCHES IN S.MONO AND SE MINERAL
COUNTIES. SNOW LEVELS ARE FORECAST TO START AROUND 8.5-9.5 KFT ON
SUNDAY, FALL TO AROUND 6-7 KFT BY MONDAY MORNING, AND THEN RISE UP
TO AROUND 7-7.5 KFT ON MONDAY AFTERNOON. THE LATEST NBM RUN SHOWS
A 60-80% PROBABILITY OF THE HIGHEST PEAKS OF THE SIERRA WITH 4+
INCHES OF SNOWFALL BY TUESDAY MORNING. THERE'S ALSO A 10-25% FOR
AROUND 1 INCH OF SNOW AT LAKE LEVEL IN THE TAHOE REGION. WHILE
SEVERE WEATHER IS NOT ANTICIPATED, THERE AROUND A 10% OR LESS
CHANCE FOR ISOLATED THUNDERSTORMS ON BOTH DAYS SOUTH OF I-80. THE
LATEST WPC EXCESSIVE RAINFALL OUTLOOK SHOWS A MARGINAL (5%) RISK
FOR HEAVY RAINFALL THAT COULD LEAD TO LOCALIZED FLASH FLOODING ON
MONDAY IN PORTIONS OF W.NEVADA SOUTH OF I-80. THERE'S STILL SOME
UNCERTAINTY WITH THIS UPCOMING WETTER AND COLDER SYSTEM, SO PLEASE
CONTINUE TO WATCH FOR FORECAST UPDATES ESPECIALLY IF YOU HAVE
HOLIDAY PLANS.
THE COOLING TREND DOES CONTINUE THROUGH MONDAY WITH THE SYSTEM
ALLOWING FOR COLDER AIR TO FLOW IN FROM THE NORTH. DAYTIME
TEMPERATURES ARE FORECAST TO BE AROUND 15-20 DEGREES BELOW
SEASONAL NORMALS ON MONDAY. MONDAY NIGHT INTO EARLY TUESDAY WILL
BE EXTRA CHILLY FOR MID-OCTOBER WITH OVERNIGHT LOWS IN THE LOW TO
MID-30S FOR W.NEVADA VALLEYS AND IN THE UPPER TEENS TO MID-20S
RANGE FOR THE SIERRA COMMUNITIES. PLEASE PREPARE YOURSELF AND
YOUR PROPERTY NOW FOR THIS UPCOMING COLD OVER THE NEXT FEW NIGHTS.
ON TUESDAY, THE MOISTURE WITH THE SYSTEM MOVES EASTWARD AS FORECAST
GUIDANCE BEGINS TO TREND WARMER AND DRIER THROUGH THE REST OF THE
WEEK. -078
AVIATION
VFR CONDITIONS ARE EXPECTED ACROSS ALL AREA TAF SITES TODAY AND
TONIGHT. AHEAD OF AN APPROACHING COLD FRONT, SOUTHWEST WINDS
GUSTING UP TO BETWEEN 30-40 KTS ARE EXPECTED THROUGH 11/03Z AT
SIERRA FRONT TERMINALS AND THROUGH 11/09Z AT SIERRA TERMINALS.
SIERRA RIDGE TOP WINDS GUSTING UP TO 60-70 KTS ARE FORECAST
THROUGH 11/12Z, SO EXPECT MOUNTAIN WAVE TURBULENCE AND LLWS.
CLOUD COVER AND SHOWER CHANCES INCREASE ON SUNDAY IN THE WAKE OF
THE COLD FRONT PASSAGE. BY SUNDAY NIGHT INTO MONDAY, MOISTURE
FROM TROPICAL STORM RACHEL ALLOWS SHOWER AND HIGH ELEVATION SNOW
CHANCES TO INCREASE EVEN FURTHER. -078
FIRE WEATHER
THE SEASON’S FIRST POTENT COLD FRONT BRINGS INCREASING SOUTHWEST
WINDS TODAY AS IT MOVES THROUGH NE CALIFORNIA AND W.NEVADA. WINDS
COMBINED WITH LOW HUMIDITY AND DRY CONDITIONS WILL ALLOW PERIODS OF
CRITICAL FIRE WEATHER CONDITIONS.
TODAY: WINDS PEAK THIS AFTERNOON AND EVENING, WITH WIDESPREAD GUSTS
OF 35-45 MPH MAINLY SOUTH OF I-80. HUMIDITY WILL INCREASE ACROSS NE
CALIFORNIA AND FAR NW NEVADA, WHILE AREAS SOUTH OF I-80 MAY SEE
CONTINUED ELEVATED CONCERNS WITH A MORE MARGINAL MINIMUM RH OF 15-
20% THIS AFTERNOON. RED FLAG WARNINGS REMAIN IN EFFECT THROUGH THIS
EVENING DUE TO STRONG WINDS AND LOW RH FOR PORTIONS OF W.NEVADA
INCLUDING THE SIERRA FRONT AND THE E.SIERRA FROM E.ALPINE COUNTY
INTO MONO COUNTY.
SUNDAY ONWARD: BEHIND THE FRONT, TEMPERATURES COOL DOWN DRASTICALLY
GOING INTO NEXT WEEK. HIGH TEMPERATURES ON MONDAY ARE FORECAST TO
BE IN THE 50S FOR W. NEVADA AND IN THE 40S FOR THE E. SIERRA
COMMUNITIES. WETTING RAIN POTENTIAL INCREASES SUNDAY-MONDAY,
MAINLY SOUTH OF I-80, AS REMNANT MOISTURE FROM TROPICAL STORM
RACHEL MOVES NORTHWARD. THE MOISTURE’S TRACK AND PRECIPITATION
TOTALS STILL SHOW GOOD UNCERTAINTY AT THIS TIME, BUT THE OVERALL
TREND HAS BEEN WETTER. -HRICH/078
REV WATCHES/WARNINGS/ADVISORIES
NV...RED FLAG WARNING UNTIL 9 PM PDT THIS EVENING NVZ420-421-423-429.
LAKE WIND ADVISORY UNTIL 11 PM PDT THIS EVENING NVZ001>004.
CA...RED FLAG WARNING UNTIL 9 PM PDT THIS EVENING CAZ274.
LAKE WIND ADVISORY UNTIL 11 PM PDT THIS EVENING CAZ072-073.
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