072
FXUS65 KREV 102112
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
212 PM PDT MON AUG 10 2026
KEY MESSAGES
* INCREASED SOUTHWEST BREEZES WILL ELEVATE FIRE WEATHER AND
RECREATION CONCERNS THIS AFTERNOON, WHILE SMOKE FROM ONGOING
FIRES PERSISTS ACROSS NORTHEAST CA AND WESTERN NV.
* ISOLATED SHOWERS AND THUNDERSTORMS RETURN SOUTH OF HIGHWAY 50 THIS
AFTERNOON, WITH GREATER COVERAGE TUESDAY AND MORE WIDESPREAD,
WETTER STORMS EXPECTED WEDNESDAY AND THURSDAY.
* HEAT WILL EASE SLIGHTLY BUT LINGER THROUGH TUESDAY ACROSS WEST
CENTRAL NV, FOLLOWED BY SUBSTANTIALLY COOLER TEMPERATURES FOR THE
REMAINDER OF THE WEEK.
DISCUSSION
WEBCAMS AROUND MIDDAY SHOW SMALL, GENERALLY SHALLOW SMOKE PLUMES
FROM THE BUG, FRED MOUNTAIN, AND IRONWOOD FIRES, WHILE THE NEWLY
REPORTED STALLION FIRE ABOUT 3 MILES NORTHWEST OF PAH RAH MOUNTAIN
CONTINUES TO PRODUCE INTERMITTENT BURSTS OF SMOKE. REGIONAL SMOKE
FROM OREGON ALSO REMAINS ACROSS NORTHEAST CA AND NORTHWEST NV.
MIXING HEIGHTS ARE FORECAST TO REACH 12-15 KFT AGL THIS AFTERNOON
WITH WEST-SOUTHWEST TRANSPORT WINDS, PROVIDING EXCELLENT VENTILATION
AND SOME IMPROVEMENT IN VALLEY SMOKE AND HAZE. LOCAL PLUMES WILL BE
CARRIED MAINLY EAST-NORTHEAST, WHILE SMOKE MAY SETTLE BACK INTO
VALLEYS TONIGHT AS MIXING COLLAPSES. THE SAME WEST-SOUTHWEST FLOW
WILL PRODUCE GUSTS OF 30-35 MPH, WHICH COMBINED WITH CRITICALLY LOW
RH WILL CREATE A 1-4 HOUR WINDOW OF ELEVATED TO LOCALLY CRITICAL
FIRE-WEATHER CONDITIONS, ESPECIALLY ACROSS NORTHEAST CA, NORTHWEST
NV, AND NEAR THE WESTERN NV FIRES. PLEASE SEE THE FIRE WEATHER
SECTION FOR MORE INFORMATION. ISOLATED THUNDERSTORMS REMAIN POSSIBLE
OVER MONO, MINERAL, AND SOUTHERN LYON COUNTIES (15-20%), WITH
LIGHTNING AND HREF-SUPPORTED OUTFLOWS OF 40-50 MPH CAPABLE OF
REACHING WELL BEYOND RAIN CORES. ONE LAST HOT AFTERNOON IS EXPECTED,
WITH SOME LOWER WESTERN NV VALLEYS REACHING 100-102 DEGREES.
THE FOUR CORNERS RIDGE WILL CONTINUE TO FLATTEN AS A COMPACT LOW
DEVELOPS NEAR THE CA COAST AND DRIFTS INLAND TUESDAY THROUGH
THURSDAY. INCREASING SOUTHERLY FLOW AHEAD OF THIS FEATURE WILL DRAW
DEEPER MOISTURE NORTHWARD, WITH PWATS RISING TO 0.6-0.9 INCH AND
LOCALLY APPROACHING 1 INCH WEDNESDAY AND THURSDAY. THUNDERSTORM
CHANCES INCREASE TO 25-50% SOUTH OF I-80 TUESDAY, ALTHOUGH A DEEP
AND DRY SUBCLOUD LAYER WILL LIMIT WETTING RAINFALL FROM MANY STORMS.
LIGHTNING AND NEW FIRE STARTS WILL THEREFORE REMAIN THE PRIMARY
CONCERNS, ALONG WITH HREF-SUPPORTED OUTFLOWS OF 45-55 MPH OVER
MINERAL COUNTY AND THE ADJACENT BASIN AND RANGE. AS THE LOW
APPROACHES WEDNESDAY AND THURSDAY, STORM CHANCES INCREASE TO 45-65%
SOUTH OF I-80 AND 25-45% NORTH OF I-80. STORMS WILL BECOME
PROGRESSIVELY WETTER, SHIFTING THE CONCERN TOWARD LOCALLY HEAVY
RAINFALL AND FLASH FLOODING NEAR BURN SCARS, STEEP TERRAIN, AND POOR-
DRAINAGE AREAS. PROXIMITY OF THE LOW MAY ALSO SUPPORT SHOWERS AND
ISOLATED LIGHTNING OUTSIDE THE TYPICAL AFTERNOON-EVENING PERIOD.
HIGHS FALL INTO THE 80S ACROSS MOST LOWER ELEVATIONS AND THE 70S FOR
SIERRA COMMUNITIES BY THURSDAY, ROUGHLY 15-20 DEGREES COOLER THAN
TODAY.
FROM FRIDAY THROUGH NEXT MONDAY, SYNOPTIC ASCENT AND MID-LEVEL
COOLING ASSOCIATED WITH THE INITIAL DISTURBANCE SHIFTS EAST AND
STORM COVERAGE SHOULD TREND DOWN FROM ITS MIDWEEK PEAK. A COMPLETE
DRY-OUT IS NOT EVIDENT, HOWEVER, AS ENSEMBLE GUIDANCE MAINTAINS A
BROAD WESTERN TROUGH, BELOW-NORMAL HEIGHTS, AND RESIDUAL MOISTURE
OVER THE REGION. A SECOND PACIFIC DISTURBANCE MAY APPROACH THE CA
COAST LATE IN THE WEEKEND OR EARLY MONDAY, MAINTAINING LOW-END DAILY
THUNDERSTORM CHANCES AND POTENTIALLY PRODUCING ANOTHER INCREASE IN
COVERAGE DEPENDING ON ITS EVENTUAL TRACK. THE GREATEST CHANCES
SHOULD FAVOR AREAS EAST OF THE SIERRA AND ACROSS THE BASIN AND
RANGE. GRADIENT WINDS REMAIN WEAKER THAN TODAY, SO FIRE-WEATHER
CONCERNS WILL BECOME MORE LOCALIZED AND TIED PRIMARILY TO LIGHTNING
AND CONVECTIVE OUTFLOWS. TEMPERATURES REBOUND MODESTLY AFTER
THURSDAY BUT REMAIN NEAR TO SLIGHTLY BELOW MID-AUGUST AVERAGES, WITH
LOWER WESTERN NV VALLEYS GENERALLY IN THE MID 80S TO NEAR 90 AND
SIERRA COMMUNITIES IN THE 70S. CONFIDENCE IS MODERATE IN THE OVERALL
COOLER AND UNSETTLED PATTERN, BUT LOWER REGARDING THE DAILY
PLACEMENT AND TIMING OF STORMS THIS WEEKEND INTO MONDAY.
-JOHNSTON
AVIATION
VFR CONDITIONS WILL PREVAIL OUTSIDE CONVECTION AND LOCALIZED SMOKE
IMPACTS THROUGH TUESDAY. SOUTHWEST TO WEST WINDS STRENGTHEN THIS
AFTERNOON, WITH GUSTS OF 20-25 KT AT MOST TERMINALS BEFORE EASING
BETWEEN 02-04Z AND BECOMING LIGHT OVERNIGHT. ISOLATED THUNDERSTORMS
REMAIN FOCUSED SOUTH OF THE MAIN WESTERN NV TERMINALS TODAY, WITH A
15-20% CHANCE AT KMMH AND VCTS FAVORED FROM ROUGHLY 22-03Z.
ANY CELL COULD PRODUCE ABRUPT OUTFLOWS OF 35-45 KT AND WIND-
DIRECTION CHANGES WELL BEYOND THE PRECIPITATION CORE. TUESDAY
THUNDER PROBABILITIES RISE TO AROUND 25% AT KMMH AND 15% AT KRNO-
KCXP-KMEV, WHILE REMAINING BELOW 10% AT KTRK-KTVL. TUESDAY STORMS
MAY PRODUCE OUTFLOWS OF 40-50 KT. MORE FREQUENT CONVECTION AND
GREATER TERMINAL IMPACTS ARE EXPECTED WEDNESDAY AND THURSDAY, WITH
ACTIVITY POTENTIALLY EXTENDING BEYOND THE USUAL AFTERNOON AND
EVENING PERIOD.
SMOKE FROM LOCAL FIRES IS PRODUCING FU NORTH THROUGH NORTHEAST OF
KRNO, WHILE SMOKE FROM OREGON CONTINUES ACROSS NORTHEAST CA AND
NORTHWEST NV. P6SM SURFACE VISIBILITY SHOULD PREVAIL AT THE MAIN
TERMINALS, ALTHOUGH SLANTWISE VISIBILITY AND TERRAIN OBSCURATION MAY
BE REDUCED NEAR AND DOWNWIND OF THE SMOKE PLUMES. DEEP AFTERNOON
MIXING AND WEST-SOUTHWEST TRANSPORT WINDS SHOULD IMPROVE SURFACE
CONDITIONS, FOLLOWED BY RENEWED SMOKE AND HAZE OVERNIGHT AND TUESDAY
MORNING AS WINDS AND MIXING DIMINISH.
-JOHNSTON
FIRE WEATHER
* TODAY AND TONIGHT: GUSTY WEST/SOUTHWEST WINDS OF 25-35 MPH AND
LOW RH WILL CREATE A FEW HOURS OF CRITICAL FIRE WEATHER
CONDITIONS THIS AFTERNOON ACROSS NORTHEAST CA AND NORTHWEST NV.
THIS WILL DIRECTLY IMPACT ONGOING WILDFIRES IN WASHOE AND
DOUGLAS COUNTIES. POOR OVERNIGHT RECOVERIES (20-40%) TONIGHT
MAY KEEP FIRES ACTIVE OVERNIGHT TONIGHT.
* TUESDAY: AN ENHANCED ZEPHYR BREEZE RETURNS IN THE AFTERNOON
THOUGH WINDS WON'T BE AS STRONG AS MONDAY (TODAY). THERE WILL BE
A 30-50% CHANCE OF SHOWERS AND THUNDERSTORMS OVER MONO, DOUGLAS,
S LYON, AND MINERAL COUNTIES, WHICH WILL CARRY A THREAT OF DRY
THUNDERSTORMS AND OUTFLOW WINDS OF 40+ MPH.
* WEDNESDAY THROUGH FRIDAY: A MAJOR PATTERN CHANGE ARRIVES MID-
WEEK, BRINGING COOLER TEMPERATURES AND HIGHER AFTERNOON RH.
INCREASED MONSOONAL MOISTURE WILL MOVE IN TO THE REGION,
SUPPORTING DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS OVER
PARTS OF WESTERN NV AND THE EASTERN SIERRA. WITH THESE STORMS
COMES THE THREATS OF HEAVY RAINFALL AND POTENTIAL FLASH
FLOODING, ISOLATED DRY T-STORMS NORTH OF I-80 INCLUDING THE
RENO-SPARKS AREA, AND GUSTY OUTFLOW WINDS.
-JUSTIN
REV WATCHES/WARNINGS/ADVISORIES
NV...NONE.
CA...NONE.
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