004  
FXUS66 KEKA 060821  
AFDEKA  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE EUREKA CA  
121 AM PDT THU AUG 6 2026  
   
KEY MESSAGES
 
 
* MODERATE TO MAJOR HEAT RISK CONTINUES THROUGH THE WEEKEND FOR  
MUCH OF THE INTERIOR.  
 
* COASTAL STRATUS TO CONTINUE FOR MUCH OF THE NORTH COAST.  
 
* INCREASED WINDS AND LOW RELATIVE HUMIDITY WILL ELEVATE FIRE  
DANGER THIS WEEKEND.  
 

 
   
SYNOPSIS
 
PERSISTENT HIGH PRESSURE ALOFT WILL REMAIN THROUGH  
THE WEEK. INLAND AREAS ARE SUBJECT TO ABNORMALLY HOT TEMPERATURES OF  
THROUGH THE WEEKEND. COASTAL AREAS WILL REMAIN MOSTLY OVERCAST  
WITH TEMPERATURES IN THE LOWER 60S NEAR THE WATER.  
 

 
   
DISCUSSION
 
A STEADY RIDGE OF HIGH PRESSURE CONTINUES TO IMPACT  
THE WEST THIS WEEK LEADING TO WARM TO VERY HOT TEMPERATURES FOR THE  
INLAND AREAS. MOST INLAND VALLEYS CAN EXPECT HIGH TEMPERATURES  
BETWEEN 100-110DEGF THROUGH THE WORK WEEK. THE COAST CONTINUES TO  
OFFER SOME RELIEF FROM THIS HEAT. OFFSHORE STRATUS IS BLANKETING  
MUCH OF THE WESTERN SEABOARD FROM THE MEXICAN BOARDER UP THROUGH  
OREGON. TEMPERATURES WILL STRUGGLE TO REACH 65DEGF FOR COASTAL  
COMMUNITIES DUE TO THIS COMPRESSED MARINE LAYER. HOWEVER, ABOVE  
AVERAGE SSTS WILL LIMIT THE LIKELIHOOD OF ANY TRUE DAYTIME FOG.  
 
THE WEATHER PATTERN WILL HAVE MINIMAL CHANGES THROUGH THE WEEK AS  
THIS HIGH PRESSURE IS EXPECTED TO REMAIN OVERHEAD. A SHORTWAVE  
MOVING BY TO THE NORTH WILL BRING SLIGHTLY COOLER TEMPERATURES  
TODAY, ALTHOUGH THIS WILL BE SHORTLIVED. SOME WARMING IS EXPECTED  
FRIDAY AND SATURDAY. A SLIGHT CHANGE IN WEATHER IS POSSIBLE THIS  
WEEKEND. CLUSTER AND DETERMINISTIC GLOBAL MODEL ANALYSIS SHOWS  
THIS HIGH PRESSURE RIDGE BEGINNING TO EVOLVE INTO A MORE FLATTER  
RIDGE THROUGH THE WEEKEND LEADING TO POTENTIAL ZONAL OR EVEN  
SLIGHT UPPER LEVEL TROUGHING ENTERING NEXT WEEK. IF THIS SOLUTION  
MATERIALIZES, IT COULD LEAD TO INCREASED WINDS NEAR THE SURFACE  
WITH HOT AND DRY CONDITIONS EXPECTED TO CONTINUE SATURDAY. THESE  
WEATHER ELEMENTS TOGETHER CAN LEAD TO INCREASED CRITICAL FIRE  
WEATHER CONCERNS. UNTIL THEN HOWEVER, EXPECT WARM INTERIOR  
TEMPERATURES AND FOGGY NIGHTTIME HOURS ALONG THE COAST. SOME  
SLIGHTLY COOLER TEMPERATURES WILL START LOWER THE HEAT RISK SUNDAY  
WITH SOME ADDITIONAL COOLING NEXT WEEK. MKK/EYS  
 

 
   
AVIATION
 
MODEL GUIDANCE IS ON THE PESSIMISTIC SIDE FOR THE  
OVERNIGHT FLIGHT CONDITIONS. WHEN TAKING THE PREVIOUS OVERNIGHT  
CONDITIONS INTO CONSIDERATION ALONG WITH SIMILAR SET UP,  
PERSISTENCE AND CAUTION ARE WISE. LIFR CONDITIONS WITH CEILINGS  
UNDER 500FT ARE IN PLACE THIS MORNING AT KCEC AND KACV. WITH  
OFFSHORE STRATUS ENCROACHING ON THE COASTLINE AND ALREADY MAKING  
ITS WAY UP THE RIVER VALLEYS, THURSDAY MORNING WILL PROVE TO BE AN  
LIFR SITUATION UNTIL THE LATE MORNING/EARLY AFTERNOON THURSDAY.  
STABLE AIR MASS AND SUBSIDENCE ARE HELPING SOCK THE COASTAL  
TERMINALS IN. KUKI WILL HAVE PREVAILING VFR CONDITIONS AS THE  
DEPTH OF MOISTURE PROFILE MAY NOT OVERCOME OROGRAPHIC OBSTACLES  
INTO THE VALLEY. /EYS  
 

 
   
MARINE
 
ONE MORE DAY OF GENTLE TO MODERATE BREEZES ARE EXPECTED  
ACROSS THE WATERS. THERE MAY A FEW AREAS OF SOUTHERLY WINDS  
LINGERING NEAR THE COAST THIS MORNING, BUT THESE WILL MAINLY TURN  
NORTHERLY THIS AFTERNOON.  
 
FRIDAY AND INTO THE WEEKEND, A MORE UNIFORM REGIME OF NORTHERLY  
WINDS ARE FORECASTED TO RETURN TO THE AREA. GALES ARE POSSIBLE  
OVER THE WEEKEND INTO EARLY NEXT WEEK WITH THE LIKELIHOOD OF GUSTS  
>30KTS OVER 80% FOR MOST OF THE OUTER WATERS FROM SATURDAY  
THROUGH MOST OF NEXT WEEK. CONDITIONS WITH THESE INCREASED WINDS  
WILL LIKELY CAUSE FOR MARINE HAZARDS. PLAN ANY SEAFARING  
ACCORDINGLY WITH THIS WEATHER CHANGE HAPPENING FRIDAY AFTERNOON.  
 

 
   
FIRE WEATHER
 
CONDITIONS ARE EXPECTED TO REMAIN HOT AND DRY  
THROUGH FRIDAY. THIS HEAT WAVE WILL LIKELY CAUSE AN INCREASE IN  
FIRE RISK AS THE FUELS DRY. THIS WEEKEND, THE SYNOPTIC WEATHER  
PATTERN IS LIKELY TO CHANGE EVER SO SLIGHTLY. THIS CHANGE WILL BE  
FELT BY AN INCREASE IN THE LIKELIHOOD OF STRONGER VALLEY WINDS  
EACH AFTERNOON. THE PRIMARY AREAS OF CONCERN ARE IN THE EASTERN  
TRINITY RIVER VALLEY AND ON THE EASTERN SIDE OF CLEAR LAKE IN LAKE  
COUNTY. WATCH FOR UPDATES AS FORECAST CONFIDENCE INCREASES ON  
THIS POTENTIAL WEATHER CHANGE.  
 

 
   
EKA WATCHES/WARNINGS/ADVISORIES
 
 
CA...  
HEAT ADVISORY UNTIL 11 PM PDT THIS EVENING FOR CAZ105-106.  
 
HEAT ADVISORY UNTIL 11 PM PDT FRIDAY FOR CAZ108-116-117.  
 
HEAT ADVISORY FROM 11 AM TO 11 PM PDT FRIDAY FOR CAZ110-111-  
113-114-118>120.  
 
NORTHWEST CALIFORNIA COASTAL WATERS...  
NONE.  

 
 

 
 
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