377  
FXUS66 KEKA 061046  
AFDEKA  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE EUREKA CA  
346 AM PDT SUN SEP 6 2026  
   
KEY MESSAGES
 
 
- SLIGHT CHANCE OF SHOWERS OR A COUPLE THUNDERSTORMS TUESDAY OVER  
INTERIOR DEL NORTE AND TRINITY COUNTY SUNDAY.  
 
- OVERNIGHT TEMPERATURES FOR THE INTERIOR WILL REMAIN CHILLY, YET  
FOG FORMATION COULD INHIBIT ANY FROST FORMING WITHIN INLAND VALLEYS.  
 
- A BUILDING DESERT SOUTHWEST RIDGE WILL SHARPLY INCREASE INTERIOR  
TEMPERATURES MONDAY, FOLLOWED BY FURTHER WARMING TO ABOVE  
AVERAGE TEMPERATURES INTO LATE NEXT WEEK.  
 

 
   
SYNOPSIS
 
A SLIGHT CHANCE FOR SHOWERS OR ISOLATED THUNDERSTORMS  
THIS SUNDAY IN DEL NORTE AND EXTREME NE HUMBODLT AND TRINITY  
COUNTIES. THIS UNSETTLED PATTERN COULD ALSO DISRUPT DIURNAL  
COASTAL STRATUS THIS WEEKEND. COLDER MORNING TEMPERATURES COULD  
OCCUR FOR THE COLDEST INTERIOR VALLEYS THIS MORNING WHEREVER FOG  
DOES NOT FORM. A SHARP WARMUP IN TEMPERATURES WILL BEGIN MONDAY  
AND CONTINUE INTO LATE NEXT WEEK.  
 

 
   
DISCUSSION
 
SUNDAY, A SHORTWAVE DISTURBANCE PASSING OVER THE  
FORECAST AREA IS INCREASING THE RAINFALL CHANCES FOR THE DEL NORTE  
AND THE NORTHERN PORTIONS OF TRINITY AND HUMBOLDT COUNTIES. A  
VERY SLIGHT LIGHTNING CHANCE EXISTS FOR THESE AREAS WELL, YET NW  
STORM MOTION WILL LIKELY CAUSE ANY STORMS THAT DO FORM TO FLOW  
INTO SISKIYOU COUNTY QUICKLY. EVEN THE MOST EXTREME CAMS SHOW VERY  
LIMITED COVERAGE OF SHORT LIVED THUNDERSTORMS OVER THE AREA.  
LITTLE CHANCES FOR WETTING RAIN (>0.10") EXIST FOR AREAS AWAY FROM  
THE HIGH TERRAIN INLAND FOR SUNDAY AS WELL.  
 
A SHARP WARMUP WILL BEGIN MONDAY AS A STRONG DESERT SOUTHWEST RIDGE  
DEVELOPS. TEMPERATURES IN THE INTERIOR VALLEYS MAY NEAR OR REACH 100  
MID TO LATE NEXT WEEK. OF NOTE, 70S ARE POSSIBLE TO THE COAST,  
WITH MID 80S TO LOW 90S NOT TOO FAR INLAND. THESE VALUES WOULD  
BRING A MODERATE HEATRISK TO THE REGION, INCLUDING CLOSER TO THE  
COAST. NBM HAS HIGH CHANCES FOR THIS OCCURRENCE. AFTER THE STRETCH  
OF COOLER WEATHER FROM PERSISTENT TROUGHING, THE FAST WARM UP  
WILL NOT ALLOW FOR MUCH ACCLIMATION TIME. LIKELY AIDED BY OFFSHORE  
WINDS, WEDNESDAY LOOKS LIKE THE WARMEST DAY OF THE STRETCH.  
 
THERE ARE REMAINING QUESTIONS ABOUT WHETHER TROPICAL MOISTURE MAY  
STREAM NORTHEAST TOWARD THE REGION FROM DECAYING TROPICAL SYSTEMS  
WELL OFF THE CA COAST. MODEL GUIDANCE HAS A LARGE VARIANCE IN  
POSSIBILITIES RANGING FROM COMPLETELY DRY AFTER SUNDAY TO SEVERAL  
CHANCES OF SHOWERS AND POSSIBLY THUNDERSTORMS LATE WEEK OR THROUGH  
THE WEEKEND. NBM CHANCES FOR A WETTING RAIN OF AT LEAST 0.1 INCH  
ARE ONLY 25% AT THIS TIME FRIDAY AND THROUGH NEXT WEEKEND  
HOWEVER.  
 

 
   
AVIATION
 
CALM WINDS CONTINUE THROUGH SUNDAY MORNING. A PASSING  
SHORTWAVE TROUGH IS DEEPENING THE MARINE LAYER, BUT A SHALLOW  
LAYER HAS PERSISTED TO BRING LIFR CEILINGS. INSTABILITY  
ASSOCIATED WITH THE TROUGH LOOKS TO HELP DISRUPT THE LOW LEVEL  
INVERSION SUNDAY. THE ONLY HINDRANCE TO FASTER CLEARING FOR THE  
COASTAL TERMINALS WILL BE WEAK SOUTHERLY WINDS AROUND AN EXPECTED  
COASTAL EDDY. SOME NORTHWEST WINDS DELIVER SOME GUSTS OVER THE  
AFTERNOON HOURS WHILE INTERIOR TERMINALS STAY VFR.  
 

 
   
MARINE
 
NORTHERLY WINDS HAVE STRENGTHENED, MAINLY OVER THE  
SOUTHERN WATERS. A MID PERIOD NW SWELL IS SUBSIDING. HURRICANE  
MARIE HAS DELIVERED A LONG PERIOD SOUTHERLY SWELL UP TO 5 FT AT 17  
SECONDS WHICH WILL REMAIN IN THE WATERS INTO NEXT WEEK. THE  
NORTHERLIES BEGIN TO STRENGTHEN SUNDAY AFTERNOON THROUGH MONDAY  
WITH WINDS 20 TO 25 KTS. WINDS WILL BEGIN TO EASE LATE TUESDAY AS  
A STRONG AREA OF HIGH PRESSURE BUILD IN FROM THE SE. WEDNESDAY  
LOOKS TO GIVE A BREAK IN WINDS WITH SOME OFFSHORE FLOW OVER THE  
COAST. THERE IS SOME UNCERTAINTY IN HOW FAST THE NORTHERLIES  
RESTRENGTHEN THURSDAY OR FRIDAY.  
 

 
   
BEACH HAZARDS
 
HURRICANE MARIE IS USHERING IN A LONG PERIOD  
SOUTHERLY SWELL OF 3-5 FEET AT 17 SECONDS FOR SOUTH FACING BEACHES  
IN MENDOCINO AND SOUTHERN HUMBOLDT COUNTIES, INCLUDING THE LOST  
COAST TRAIL TODAY THROUGH INTO SUNDAY. THUS, THERE IS AN ONGOING  
RISK OF SNEAKER WAVES, ESPECIALLY IF THE SWELL COMES IN SLIGHTLY  
LARGER.  
 
SNEAKER WAVES ARE A UNIQUE HAZARD, WITH UP TO 30 MINUTES BETWEEN  
WAVES. LARGE, UNEXPECTED WAVES CAN SWEEP ACROSS THE BEACH WITHOUT  
WARNING, SWEEPING PEOPLE INTO THE SEA FROM ROCKS, JETTIES, AND  
BEACHES. THESE SNEAKER WAVES CAN ALSO MOVE LARGE OBJECTS SUCH AS  
LOGS, CRUSHING ANYONE CAUGHT UNDERNEATH. EVEN ANKLE TO KNEE DEEP  
WATER CAN KNOCK YOU DOWN AND DRAG YOU OUT WHEN A SNEAKER WAVE HITS.  
PAY ATTENTION AND STAY ABOVE THE HIGH WATER LINE AND ANY WET SAND TO  
STAY SAFE. IF THE GROUND IS WET, WAVES HAVE SURGED THERE RECENTLY.  
STAY SAFE AND NEVER TURN YOUR BACK ON THE OCEAN!  
 

 
   
EKA WATCHES/WARNINGS/ADVISORIES
 
 
CA...  
BEACH HAZARDS STATEMENT THROUGH MONDAY EVENING FOR CAZ104-  
109.  
 
NORTHWEST CALIFORNIA COASTAL WATERS...  
SMALL CRAFT ADVISORY FROM 2 PM SUNDAY TO 5 AM PDT MONDAY  
FOR PZZ455.  
 
SMALL CRAFT ADVISORY FROM 2 PM SUNDAY TO 5 PM PDT MONDAY  
FOR PZZ475.  
 

 
 

 
 
NOTE: THE FULL FORECAST DISCUSSION IS NOW REGULARLY ISSUED BETWEEN  
10 AM/PM AND 1 PM/AM. ADDITIONAL UPDATES WILL BE ISSUED AS NEEDED.  
 
VISIT US AT HTTPS://WWW.WEATHER.GOV/EUREKA  
 
FOLLOW US ON FACEBOOK AND TWITTER AT:  
HTTPS://WWW.FACEBOOK.COM/NWSEUREKA  
HTTPS://WWW.TWITTER.COM/NWSEUREKA  
 
FOR FORECAST ZONE INFORMATION  
SEE THE FORECAST ZONE MAP ONLINE:  
HTTPS://WWW.WEATHER.GOV/IMAGES/EKA/ZONEMAP.PNG  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab CA Page Main Text Page