143
FXUS65 KREV 220817
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
117 AM PDT SAT AUG 22 2026
KEY MESSAGES
* GUSTY SOUTHWEST WINDS TODAY BRING CRITICAL FIRE WEATHER
CONDITIONS AND LAKE RECREATION IMPACTS TO PARTS OF NORTHEAST CA,
NORTHWEST NV.
* SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ACROSS PARTS OF THE
EASTERN SIERRA AND WESTERN NV TODAY AND TOMORROW.
* SEASONAL TEMPERATURES, OVERALL DRY CONDITIONS AND AFTERNOON
BREEZES PREVAIL FOR MUCH OF NEXT WEEK.
DISCUSSION
A FEW LIGHT SHOWERS PERSIST EARLY THIS MORNING OVER PORTIONS OF
THE CWA. MOST OF THIS ACTIVITY SHOULD BE DONE BY SUNRISE. HOWEVER,
MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON OVER
PORTIONS OF WESTERN NV AND THE EASTERN SIERRA. THE MAIN AREA OF
CONCERN WILL BE MINERAL, AND EASTERN MONO/CHURCHILL/PERSHING
COUNTIES, WHERE WE HAVE THE HIGHEST CHANCES OF PRECIPITATION OF
30-40%. HOWEVER, STORM CHANCES REMAIN AT 15-25%. THEREFORE, EXPECT
SCATTERED SHOWERS AND ISOLATED TO SCATTERED THUNDERSTORMS IN THE
AFOREMENTIONED AREAS. THE MAIN CONCERNS WITH ANY STORM WILL BE
GUSTY OUTFLOW WINDS TO 40 MPH, FREQUENT LIGHTNING, PERIODS OF
HEAVY RAIN WITH THE STRONGEST CELLS THAT COULD LEAD TO FLASH
FLOODING, AND SMALL HAIL.
FURTHERMORE, THE POSITION OF THE UPPER RIDGE CENTERED OVER THE
DESERT SOUTHWEST AND AN UPPER TROUGH MOVING INLAND INTO THE PACNW
WILL TIGHTEN OUR PRESSURE GRADIENT AT THE SURFACE THIS AFTERNOON
LEADING TO WESTERLY GUSTS OF 30-35 MPH WITH ISOLATED LOCATIONS
HAVING A 30-60% CHANCES OF OBSERVING GUSTS TO 40 MPH OVER NE CA
AND NW NV INCLUDING THE SIERRA FRONT. LAKE WIND ADVISORIES AND A
RED FLAG WARNING ARE IN EFFECT FOR THIS REASON. FOR MORE ABOUT
FIRE WEATHER, PLEASE READ THE FIRE WEATHER SECTION BELOW.
BY SUNDAY, THE WINDS AND OUR CHANCES FOR SHOWERS AND THUNDERSTORMS
DECREASE AS THE UPPER TROUGH PUSHES THE RIDGE FARTHER EAST TOWARDS
THE SOUTHERN PLAINS, WHICH SETS THE PLUME OF MONSOONAL MOISTURE
TOWARDS CENTRAL AND EASTERN NV. SO, THE BEST CHANCE FOR
PRECIPITATION WILL BE IN THE NV BASIN AND RANGE. WINDS WILL BE
TYPICAL FOR THIS TIME OF THE YEAR.
FOR MONDAY AND BEYOND, WE REMAIN UNDER A SORT OF BLOCKY PATTERN
WITH THE RIDGE RETROGRADING BACK TOWARDS THE DESERT SOUTHWEST AND
A LONGWAVE TROUGH PERSISTING OFF THE PACNW COAST (OCCASIONALLY
SENDING SHORTWAVES INLAND). THIS PATTERN LEADS TO SEASONAL
TEMPERATURES, AFTERNOON BREEZES AND GENERALLY DRY CONDITIONS.
HOWEVER, THE PROXIMITY TO THE MONSOONAL MOISTURE PLUME COULD ALLOW
FOR ISOLATED SHOWERS AND THUNDERSTORMS IN AREAS SOUTH OF US-50.
PLUS, THE INCOMING SHORTWAVES HAVE THE POTENTIAL TO INCREASE
AFTERNOON GUSTS EVERY OTHER DAY BRINGING BACK FIRE AND RECREATION
CONCERNS THROUGHOUT THE WEEK.
-HC
AVIATION
MOSTLY VFR CONDITIONS CONTINUE WITH MID TO HIGH LEVEL CLOUDS.
MOUNTAIN OBSCURATIONS PERSIST IN THE SIERRA THROUGH 21Z-00Z THIS
AFTERNOON. SHRA/TSRA HAS A 10-40% CHANCE TO DEVELOP THIS
AFTERNOON FOR TERMINALS SOUTH OF INTERSTATE 80, DECREASING TO
10-30% SUNDAY FOR KBAN/KHTH/KNFL/KLOL. STORMS COULD BRING PERIODS
OF REDUCED CIGS AND VIS. GUSTY WINDS TO 30 KTS RETURN BETWEEN
20Z-03Z WITH SOME LOCATIONS UP TO 35 KTS. THERE IS LOW POTENTIAL
FOR MINOR TURBULENCE AND LLWS AFTER 00Z THIS EVENING.
-HC
FIRE WEATHER
FIRE WEATHER CONCERNS RETURN LATE THIS MORNING THROUGH THE
EVENING, AS WIND GUSTS INCREASE TO THE 30-40 MPH RANGE ACROSS
NORTHEAST CA, NORTHWEST NV, AND THE NORTHERN SIERRA FRONT. WHILE
HUMIDITY VALUES AREN'T EXCEEDINGLY LOW (MINIMUMS 10-18%), MOST OF
THESE AREAS DID NOT RECEIVE MUCH RAINFALL LAST WEEK, RESULTING IN
A GREATER EXTENT OF DRY VEGETATION WHERE FIRE COULD SPREAD MORE
QUICKLY WHEN THE WINDS PICK UP. THEREFORE, A RED FLAG WARNING
CONTINUES IN EFFECT FOR THESE AREAS. SO, BE EXTRA CAUTIOUS AND
FIRE SAFE, AVOID OUTDOOR RECREATION OR WORK ACTIVITIES THAT COULD
SPARK ANY FIRES.
FROM SUNDAY THROUGH NEXT WEEK, AFTERNOON BREEZES CONTINUE BUT AT
LOWER SPEEDS COMPARED TO SATURDAY. THE NEXT PERIOD TO WATCH IS
NEXT TUESDAY OR WEDNESDAY, WHEN WINDS POTENTIALLY TREND UPWARD,
WHILE AFTERNOON HUMIDITY DECREASES AS A DRY AIR MASS SETTLES IN.
-MJD/HC
REV WATCHES/WARNINGS/ADVISORIES
NV...RED FLAG WARNING FROM 11 AM TO 11 PM PDT SATURDAY NVZ420-458.
LAKE WIND ADVISORY FROM 11 AM TO 11 PM PDT SATURDAY NVZ003.
CA...RED FLAG WARNING FROM 11 AM TO 11 PM PDT SATURDAY CAZ270-278.
LAKE WIND ADVISORY FROM 11 AM TO 11 PM PDT SATURDAY CAZ071.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page