288
FXUS66 KHNX 092200
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HANFORD CA
300 PM PDT SAT MAY 9 2026
KEY MESSAGES
1. EARLY SEASON HEAT ARRIVES EARLY NEXT WEEK WITH EXPECTED
TEMPERATURES RISING TO TRIPLE-DIGIT VALUES MONDAY AND TUESDAY IN
THE SAN JOAQUIN VALLEY.
3. MODERATE HEAT RISK EXPECTED FOR THE VALLEY AREAS, WITH A
MEDIUM CHANCE FOR MAJOR HEAT RISK.
4. PRACTICE SAFETY AROUND AREA LAKES, RIVERS, AND STREAMS AS
WATERS ARE RUNNING COLD.
DISCUSSION
CURRENT SATELLITE IMAGERY AND SURFACE OBSERVATIONS CONFIRM THE
OBVIOUS: WARM AND DRY CONDITIONS PROVIDED BY SUBTROPICAL
RIDGING. THIS WILL REMAIN THE CASE FOR THE COMING DAYS, ALBEIT
WITH "HOT" BEING THE MORE APPROPRIATE ADJECTIVE AS RIDGING
BUILDS AND REACHES PEAK STRENGTH ON MONDAY. THE NBM PLACES THE
SAN JOAQUIN VALLEY UNDER A 50-60% PROBABILITY FOR AFTERNOON HIGH
TEMPERATURES ABOVE 100 DEGREES ON MONDAY, INCREASING TO 70%
ACROSS URBAN AREAS. SIMILAR PROBABILITIES WILL BE CONFINED TO
THE EDGES OF THE VALLEY AND GREATER URBAN AREAS ON TUESDAY.
WHILE OVERNIGHT LOWS IN THE 60S WILL GENERALLY PROVE TO BE
PLEASANT AND HELP WITH DAYTIME RECOVERY, THE "THERMAL BELT"
VALLEY AND FOOTHILL AREAS BETWEEN 400-1000 FT WILL ONLY COOL TO
THE UPPER 60S TO LOW 70S, LIMITING OVERNIGHT COOLING TO THOSE
UNABLE TO ACCESS AIR CONDITIONING. AS A RESULT, THE PREVAILING
MODERATE RISK FOR HEAT ILLNESS ON MONDAY AND TUESDAY HAS A
50-70% PROBABILITY TO BE MAJOR IN THESE THERMAL BELT AREAS SUCH
THAT OTHERWISE HEALTHY INDIVIDUALS ARE AT RISK FOR HEAT ILLNESS
SHOULD PROPER ACTIONS (DRINKING PLENTY OF WATER, LIMITING TIME
OUTDOORS AND IN SUNLIGHT) NOT BE TAKEN.
DRY CONDITIONS WILL PREVAIL OVER THIS WEEKEND INTO EARLY NEXT
WEEK. BY TUESDAY, THERE IS A SLIGHT (10-15 PERCENT) CHANCE FOR
THUNDERSTORMS OVER THE HIGHER ELEVATIONS OF THE SIERRA NEVADA AS
A LOW PRESSURE SYSTEM APPROACHES THE WEST COAST. OTHERWISE,
EXPECT WINDS TO ONCE AGAIN PICK UP OVER THE SIERRA NEVADA CREST
AND INTO THE KERN COUNTY DESERT. IN ADDITION, HUMIDITY WILL
CONTINUE TO LOWER UNTIL EARLY NEXT WEEK IN THE DESERT AND THE
THERMAL BELTS IN THE FOOTHILLS AND COASTAL RANGES EACH DAY AS WE
HEAT UP, AND OVERNIGHT RECOVERY WILL WORSEN.
NOTICEABLY COOLER TEMPERATURES WILL TAKE PLACE BY THE MIDDLE OF
NEXT WEEK, BUT HIGHS REMAIN ABOVE SEASONAL AVERAGES WITH
TEMPERATURES IN THE UPPER 80'S TO NEAR 90 DEGREES IN THE WARMEST
LOCATIONS. DAYTIME HUMIDITY WILL REMAIN LOW IN THESE LOCATIONS
THROUGH MUCH OF NEXT WEEK, ALTHOUGH OVERNIGHT RECOVERY WILL
IMPROVE.
LATEST CPC OUTLOOKS SHOW CONTINUED ABOVE AVERAGE TEMPERATURES
WITH A SLIGHT TILT IN THE ODDS TOWARDS ABOVE AVERAGE
PRECIPITATION AT BOTH THE 6-10 DAY AND 8-14 DAY PERIODS.
AVIATION
VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS OVER CENTRAL
CALIFORNIA.
FIRE WEATHER
WARMING OUT OF SHADE TEMPERATURES THROUGH THIS WEEKEND AND
EARLY NEXT WEEK WILL RESULT IN LOWERING RELATIVE HUMIDITIES
ACROSS THE REGION. MINIMUM RHS IN THE MOJAVE DESERT WILL FALL
BELOW 15 PERCENT ON SATURDAY. FOR SUNDAY THROUGH TUESDAY, MINRHS
ARE EXPECTED BETWEEN 5 AND 10 PERCENT IN THIS AREA. RHS WILL
FALL TO OR BELOW 20 PERCENT IN THE SAN JOAQUIN VALLEY AND SIERRA
NEVADA FRIDAY AFTERNOON AND CONTINUE AT THESE VALUES INTO THE
WEEKEND. RHS AT 15 PERCENT OR LESS ARE EXPECTED FOR THESE AREAS
ON MONDAY AND TUESDAY, WITH THE TEHACHAPI RANGE AND SOUTHERN
KERN MOUNTAINS AT OR BELOW 10 PERCENT. A DOWNTREND IN 100- AND
1000-HR DEAD FUEL MOISTURES IS ANTICIPATED WITH THIS WARMING
TREND; HOWEVER, BOTH PARAMETERS ARE EXPECTED TO REMAIN ABOVE
CRITICAL THRESHOLDS. UPSLOPING WINDS FROM THE SOUTHEAST ALONG
THE EASTERN SIERRA CAN HELP TO FURTHER DRY FUELS, ESPECIALLY IN
THE PORTION OF THE RANGE IN SOUTHERN TULARE COUNTY. NEW FIRE
STARTS MAY ALSO SPREAD MORE QUICKLY WITH INCREASED GUSTS ALONG
THE SOUTHERN SIERRA.
AIR QUALITY ISSUES
NONE.
CERTAINTY
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.HTML FOR ADDITIONAL INFORMATION
AND/OR TO PROVIDE FEEDBACK.
HNX WATCHES/WARNINGS/ADVISORIES
HEAT ADVISORY FROM 11 AM MONDAY TO 8 PM PDT TUESDAY FOR
CAZ300>317-319-321-332.
PUBLIC/AVIATION...ND
WEATHER.GOV/HANFORD
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