052
FXUS65 KREV 180747
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
1247 AM PDT WED MAR 18 2026
KEY MESSAGES
* STRONG HIGH PRESSURE WILL RESULT IN HISTORIC MARCH WARMTH THIS
WEEK.
* THE WARM TEMPERATURES WILL ACCELERATE SNOWMELT, LEADING TO
RIVERS RUNNING FAST AND COLD.
* DRY AND MILD WEATHER IS FAVORED THROUGH THE WEEKEND, BUT A
PATTERN CHANGE WITH SOME COOLING AND CHANCES FOR PRECIPITATION
RETURNS NEAR THE MIDDLE OF NEXT WEEK.
DISCUSSION
THE FIRST DAY OF RECORD HIGHS HAS OCCURRED (SEE THE CLIMATE
SECTION BELOW), ALTHOUGH THE MAXIMUM HEATING POTENTIAL WAS LIKELY
HELD BACK BY A COUPLE OF DEGREES AS THE SUN WAS FILTERED BY A
SWATH OF CIRRUS TUESDAY AFTERNOON. THE CURRENT MARCH RECORD HIGHS
FOR RENO AND SOUTH LAKE TAHOE HELD FOR ONE MORE DAY, BUT THESE
HAVE A 90+% CHANCE OF BEING BROKEN THIS AFTERNOON AS THE HIGH
PRESSURE RIDGE CENTER MOVES INLAND OVER THE SOUTHWEST US. THIS
SETS UP A MORE FAVORABLE SCENARIO FOR ADDITIONAL HEATING TO THE
MID 80S FOR WESTERN NV VALLEYS AND LOWER-MID 70S FOR SIERRA
COMMUNITIES. THE LATEST BLENDED GUIDANCE IS TARGETING FRIDAY AS
THE WARMEST OVERALL DAY OF THIS MARCH HEAT EVENT, WITH UPPER 80S
AND EVEN UP TO A 30% CHANCE OF TOUCHING 90 DEGREES FOR WARMER
VALLEYS OF WESTERN NV, WHILE E SIERRA/TAHOE SITES ARE PROJECTED TO
REACH THE MID-UPPER 70S. SMALL FLUCTUATIONS IN THE EVENTUAL
POSITION AND EXTENT OF THE RIDGE, AND TIMING OF PASSING CIRRUS
CLOUD COVER COULD STILL AFFECT THIS WEEK'S PEAK TEMPERATURE BY A
COUPLE OF DEGREES.
WITH THESE VERY WARM TEMPERATURES, EXPECT AN INCREASE IN SNOWMELT,
LEADING TO FASTER FLOWS ON LOCAL RIVERS AND CREEKS. IT MAY BE
APPETIZING TO COOL OFF IN THOSE WATERWAYS BUT THE COLD WATER
BRINGS THE DANGER OF SHOCK OR HYPOTHERMIA. SEEK SHADE OR HEAD
INDOORS FOR A SAFER WAY TO COOL OFF.
FOR THIS WEEKEND, A COOLING TREND WILL TAKE PLACE AS THE RIDGE
RETREATS SOUTHWARD IN RESPONSE TO INCREASING WESTERLY FLOW ACROSS
THE SIERRA AND WESTERN NV. RECORD HIGHS REMAIN WITHIN REACH FOR
SATURDAY BUT NOT FOR SUNDAY, WHILE WINDS TREND UPWARD TO MORE
TYPICAL ZEPHYR-TYPE LEVELS (GUSTS NEAR 25 MPH).
NEXT WEEK PRESENTS A POTENTIAL CHANGE TO A COOLER PATTERN WITH
PERIODS OF GUSTY WINDS AND VALLEY RAIN/MOUNTAIN SNOW SHOWER
CHANCES AROUND THE TUESDAY-WEDNESDAY TIME FRAME. HOWEVER,
CONFIDENCE REMAINS ON THE LOW SIDE WITH A NEARLY 20 DEGREE SPREAD
AMONG ENSEMBLE GUIDANCE FOR NEXT WEEK'S HIGHS, INCLUDING SOME
SCENARIOS BRINGING A SHORT REPRISE OF 80+ DEGREE TEMPERATURES.
OUR OVERALL FORECAST LEANS TOWARD A CONTINUED COOLING TREND,
ESPECIALLY FARTHER NORTH TOWARD THE OREGON BORDER THROUGH THE
MIDDLE OF NEXT WEEK. MEANWHILE, THE I-80 CORRIDOR SOUTHWARD HANGS
ONTO HIGHS ABOUT 10 DEGREES ABOVE LATE MARCH AVERAGES (LOWER 70S
FOR WESTERN NV VALLEYS/UPPER 50S-LOWER 60S FOR E SIERRA/TAHOE
SITES. MJD
AVIATION
VFR CONDITIONS WITH LIGHT WINDS PREVAIL FOR ALL TERMINALS THROUGH
MUCH OF THIS WEEK. THE ONLY EXCEPTION MAY BE KTRK BETWEEN 10-15Z
FOR THE NEXT FEW MORNINGS, WHERE THERE IS A 20% CHANCE OF PATCHY
FG. DENSITY ALTITUDE CONCERNS MAY ARISE DUE TO WARMING FOR W NV
TERMINALS. ADDITIONALLY, SLANTWISE VISIBILITY REDUCTIONS MAY ARISE
DUE TO HAZE TRAPPED UNDER SHARP MORNING INVERSIONS THROUGH
FRIDAY. MJD
CLIMATE
NEW RECORD HIGHS WERE SET ON 3/17 FOR BOTH RENO AND SOUTH LAKE
TAHOE, SURPASSING THE PREVIOUS RECORDS BY 4 DEGREES. HOWEVER, THE
MORNING WAS COOLER WITH NO NEW RECORDS FOR WARMEST LOWS.
BOTH AREA CLIMATE SITES (RENO AT KRNO AND SOUTH LAKE TAHOE AT KTVL)
ARE ON TRACK TO SET NEW RECORD HIGH TEMPERATURES EACH DAY THROUGH
SATURDAY. ALTHOUGH WITH LESS CERTAINTY, SOME RECORD WARM LOWS MAY
ALSO BE SET.
CURRENT RECORD HIGH TEMPERATURES FOR RENO AND SOUTH LAKE TAHOE:
DATE RENO NV SOUTH LAKE TAHOE CA
---- ------------ -------------------
3/17 82F (PREV 78F IN 2007) 69F (PREV 65F IN 2007)
3/18 77F IN 1947 63F IN 2004
3/19 77F IN 1997 65F IN 2015
3/20 81F IN 2004 68F IN 1997
3/21 80F IN 2004 68F IN 1997
-------------------------------------------------------
CURRENT RECORD WARMEST LOW TEMPERATURES FOR RENO AND SOUTH LAKE
TAHOE:
DATE RENO NV SOUTH LAKE TAHOE CA
---- ------------ -------------------
3/17 48F IN 2015 38F IN 2007
3/18 47F IN 1945 37F IN 2021
3/19 46F IN 2013 38F IN 2013
3/20 47F IN 2013 35F IN 2013
3/21 46F IN 2015 38F IN 1972
-------------------------------------------------------
WARMEST DAILY MARCH TEMPERATURES ON RECORD:
RENO, NV: 83F ON 3/31/1966
SOUTH LAKE TAHOE, CA: 71F ON 3/30/2015
REV WATCHES/WARNINGS/ADVISORIES
NV...NONE.
CA...NONE.
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