031
FXUS66 KHNX 201846
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HANFORD CA
1146 AM PDT TUE OCT 20 2026
KEY MESSAGES
1. THERE IS A HIGH CONFIDENCE IN A SIGNIFICANT CHANGE IN THE
OVERALL WEATHER PATTERN WITH TEMPERATURES CONTINUING TO
COOLDOWN AND PRECIPITATION MID-WEEK.
2. THE FIRST WETTING RAINFALL THROUGHOUT THE ENTIRE AREA IS
LIKELY WITH A 50-65% CHANCE OF AT LEAST A HALF AN INCH OF
RAINFALL BY THURSDAY EVENING.
3. SNOWFALL IS LIKELY ABOVE 8,000 FEET IN ELEVATION WITH A
55-70% CHANCE OF AT LEAST 4 INCHES OF SNOWFALL (PROBABILITIES
INCREASE FURTHER AT HIGHER ELEVATIONS).
4. THE STORM PREDICTION CENTER (SPC) HAS WESTERN KERN COUNTY IN
A LEVEL ONE OUT OF FIVE RISK FOR SEVERE WEATHER WITH A 5-14%
CHANCE FOR SEVERE WINDS TOMORROW.
DISCUSSION
A STRONG TROUGH WITH A DEEP AREA OF LOW PRESSURE HAS BEGUN TO
MOVE INTO OUR AREA OFF THE PACIFIC OCEAN. THIS IS LEADING TO
MUCH COOLER TEMPERATURES ACROSS OUR REGION AND OUR FIRST CHANCE
OF WIDESPREAD PRECIPITATION THIS FALL. TEMPERATURES WILL BE
COOLER TODAY THAN YESTERDAY AND WILL LIKELY BE NEAR TO SLIGHTLY
BELOW AVERAGE. THE PROBABILITY OF TEMPERATURES EXCEEDING 80
DEGREES TODAY WILL BE AROUND 25-40% IN THE NORTHERN VALLEY AND
65-80% IN THE SOUTHERN VALLEY. TEMPERATURES WILL BE MUCH COOLER
TOMORROW AS A LOW PRESSURE SYSTEM MOVES OFF THE PACIFIC OCEAN
AND BEGINS TO HAVE A WIDESPREAD INFLUENCE IN OUR REGION. THE
PROBABILITY OF TEMPERATURES EXCEEDING 70 DEGREES TOMORROW IS
ONLY ABOUT 35-50% ACROSS MOST OF THE VALLEY, WITH COOL AND WELL
BELOW AVERAGE TEMPERATURES REMAINING VERY LIKELY FOR THE MIDDLE
TO END OF THE WEEK. THERE WILL BE A WARM-UP IN TEMPERATURES
HOWEVER BY THE COMING WEEKEND WITH THE CHANCE OF TEMPERATURES
EXCEEDING 70 DEGREES AT AROUND 85-95% ACROSS THE VALLEY ON
SATURDAY AND SUNDAY.
IN TERMS OF PRECIPITATION, THERE IS A 10-20% CHANCE OF GENERAL
THUNDERSTORMS TODAY ALONG THE FOOTHILLS, SIERRA NEVADA
MOUNTAINS, AND MOJAVE DESERT IN EASTERN KERN COUNTY THIS
AFTERNOON THROUGH EVENING. TOMORROW, MOISTURE WILL MOVE OFF THE
PACIFIC OCEAN AND INTO OUR AREA BRINGING THE FIRST WIDESPREAD
RAINFALL IN THE VALLEY SINCE THIS PAST SPRING. PRECIPITATION
WILL LIKELY BEGIN IN OUR AREA SOMETIME BETWEEN THE MID- MORNING
AND MID- AFTERNOON. IN TERMS OF PRECIPITATION AMOUNTS, THE
PROBABILITY OF A HALF OF INCH OF RAINFALL IN THE VALLEY IS AT
AROUND 45-65% WITH SLIGHTLY HIGHER PROBABILITIES ALONG THE
SIERRAS, AND SIMILAR TO SLIGHTLY LOWER PROBABILITIES IN THE
MOJAVE DESERT. THE PROBABILITY OF THREE QUARTERS OF AN INCH OF
RAINFALL IS REDUCED TO AROUND 30-50% ACROSS MUCH OF THE VALLEY.
THE WORST CASE- SCENARIO, OR THE MOST PRECIPITATION POSSIBLE IN
THE VALLEY WOULD LIKELY BE AROUND AN INCH AND A QUARTER. AN AREA
PARTICULARLY VULNERABLE TO RAINFALL IS IN THE MOJAVE DESERT IN
KERN COUNTY, AND THIS RAINFALL FORECAST IS THEREFORE OF
PARTICULAR IMPORTANCE IN THAT AREA. THERE IS A MARGINAL CHANCE,
AT LEAST 5% CHANCE, OF EXCESSIVE RAINFALL IN THROUGH MUCH OF
KERN COUNTY AND ALONG THE SOUTHERN SIERRA NEVADA MOUNTAINS. IN
ADDITION, TO THE EXCESSIVE RAINFALL, THERE IS A CHANCE FOR
SEVERE THUNDERSTORMS WITH THIS INFLUX OF MOISTURE TOMORROW.
THUNDERSTORMS WITH SEVERE DAMAGING WINDS ARE POSSIBLE (5-14%
CHANCE) WITH THE STORM PREDICTION CENTER (SPC) HAVING WESTERN
KERN COUNTY IN A LEVEL ONE OUT OF FIVE RISK FOR SEVERE WEATHER
TOMORROW. THERE IS A GENERAL THUNDERSTORM RISK HOWEVER
THROUGHOUT THE ENTIRE AREA WITH AMPLE MOISTURE OFF THE PACIFIC
OCEAN AND A STRONG JET STREAK COMING INTO OUR AREA.
PRECIPITATION COULD LINGER AND REMAIN IN OUR AREA THROUGH MUCH
OF THE DAY THURSDAY, BUT IS THEN EXPECTED TO TAPER OFF SOMETIME
LATE IN THE DAY.
IN TERMS OF SNOWFALL, THERE IS A CHANCE FOR AT LEAST 4 INCHES OF
SNOWFALL ABOVE 8,000 FEET IN THE HIGH SIERRAS (55-70% CHANCE).
BEING STILL OCTOBER, SNOWFALL WILL REMAIN AT HIGH ELEVATIONS.
THERE IS THE POTENTIAL FOR EVEN MORE SNOWFALL AT HIGHER
ELEVATIONS WITH A 50-65% CHANCE OF AT LEAST 6 INCHES OF SNOWFALL
ABOVE 10,000 FEET. IN TERMS OF WIND GUSTS, ISOLATED WIND GUSTS
GREATER THAN 30 MPH REMAIN POSSIBLE FROM LATE THURSDAY NIGHT
INTO LATE FRIDAY NIGHT WITHIN THE SIERRA NEVADA MOUNTAIN RANGE
AND THE MOJAVE DESERT (60-75% CHANCE), AS THE LOW PRESSURE
SYSTEM BEGINS TO MOVE OUT OF OUR AREA.
THE CLIMATE PREDICTION CENTER (CPC) HAS A 33-40% CHANCE FOR
ABOVE NORMAL TEMPERATURES IN THE NEXT 6-10 DAYS AND A 40-50%
CHANCE FOR ABOVE NORMAL PRECIPITATION. HOWEVER, IN THE 8-14 DAY
OUTLOOK, THE CPC HAS US WITH NEAR NORMAL TEMPERATURES AND A
50-60% CHANCE FOR ABOVE AVERAGE PRECIPITATION. PREVIOUSLY
MENTIONED CHANCES FOR PRECIPITATION NEXT WEEKEND AND EARLY NEXT
WEEK HAVE DWINDLED, AND THERE IS ONLY ABOUT A 5% CHANCE FOR ANY
RAINFALL AT ALL WITHIN THE ENTIRE AREA.
AVIATION
VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS.
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
NONE.
PUBLIC...MC
AVIATION....MC
WEATHER.GOV/HANFORD
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