945  
FXUS66 KEKA 111956  
AFDEKA  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE EUREKA CA  
1256 PM PDT FRI JUL 11 2025  
   
SYNOPSIS
 
HIGH PRESSURE HAS BUILT IN BRINGING HOT WEATHER TO THE  
INTERIOR. THIS HEAT IS LIKELY TO LAST THE WEEKEND INTO EARLY NEXT  
WEEK. SMOKE AND HAZE REMAINS POSSIBLE FROM NEARBY WILDFIRES. THERE  
IS A SLIGHT CHANCE FOR ISOLATED DRY THUNDERSTORMS SUNDAY AFTERNOON  
IN NORTHERN TRINITY COUNTY.  
 

 
   
DISCUSSION
 
HIGH PRESSURE HAS BUILT INTO THE AREA, BRINGING A  
SHALLOW MARINE LAYER WITH DENSE FOG AT TIMES ALONG THE COAST AND HOT  
WEATHER TO THE INTERIOR. SMOKE FROM THE BUTLER AND GREEN FIRES HAS  
BLOWN INTO THE REGION THIS MORNING. SOME IMPROVEMENT IN AIR QUALITY  
IS LIKELY THIS AFTERNOON, BUT ANY REMAINING IN THE VALLEYS WILL  
LIKELY POOL BACK IN THIS EVENING AND OVERNIGHT. SMOKE MODELS ARE  
SHOWING THE TRINITY AND KLAMATH RIVER VALLEYS WITH HIGH SMOKE  
CONCENTRATIONS OVERNIGHT, AND GENERAL HAZINESS IS POSSIBLE ACROSS  
THE AREA.  
 
AS FOR THE HEAT, HIGH TEMPERATURES BETWEEN 100-110 ARE POSSIBLE,  
WITH THE HIGHEST TEMPERATURES LIKELY IN TRINITY COUNTY ALONG THE  
TRINITY RIVER VALLEY. WIDESPREAD HAZE MAY BRING HIGHS SLIGHTLY BELOW  
WHAT IS FORECAST, BUT NO MAJOR IMPACT TO TEMPERATURES ARE LIKELY.  
THE OVERNIGHT LOWS MAY ACTUALLY BE A FEW DEGREES WARMER THAN  
FORECAST (FORECAST BEING LOW TO MID 60S) IN THE VALLEYS AS DENSER  
SMOKE COULD TRAP SOME HEAT THE VALLEYS. REGARDLESS, THIS HEAT DOES  
BRING MODERATE TO MAJOR HEATRISK AND IS DANGEROUS TO THOSE WITHOUT  
PROPER COOLING AND THOSE SENSITIVE TO HEAT RELATED ILLNESS.  
 
SUNDAY, THE RIDGE BEGINS TO MOVE EAST SLIGHTLY. THIS COULD SUPPORT A  
SLIGHTLY DEEPER MARINE LAYER AND TEMPERATURES A DEGREE OR TWO LOWER  
IN INTERIOR DEL NORTE AND SOUTHERN HUMBOLDT. STILL, TEMPERATURES  
REMAIN HOT. MODELS ARE PICKING UP A MOISTURE INTRUSION FROM THE EAST  
BY SUNDAY AFTERNOON. CAMS WITHIN RANGE ARE SHOWING A LOW CHANCE  
(15%) FOR SOME ACTIVITY IN NORTHERN TRINITY COUNTY. MODEL SOUNDINGS  
DO SHOW A WEAK CAPPING INVERSION AND MOISTURE REMAINS LIMITED, SO  
CONFIDENCE REMAINS LOW.  
 
MONDAY, THE RIDGE CONTINUES TO PUSH EAST, WHICH WILL ALLOW THE  
MARINE LAYER TO SLOWLY AND GRADUALLY DEEPEN EARLY NEXT WEEK. TRIPLE  
DIGIT TEMPERATURES ARE LIKELY TO CONTINUE INTO AT LEAST MONDAY, WITH  
"COOLING" FINALLY ARRIVING BY TUESDAY AND WEDNESDAY. TEMPERATURES  
ARE LIKELY TO REMAIN WARM, WITH 90S EXPECTED FOR MUCH OF THE  
INTERIOR. JB  
 

 
   
AVIATION
 
COASTAL STRATUS LAYER IS GRADUALLY BEING SCOURED OUT BY  
INCREASING NORTHERLY WINDS OFFSHORE. A STRONG MARINE INVERSION AND  
SLIGHT SOUTHERLY REVERSAL ALONG THE NORTH COAST HAS KEPT ACV BENEATH  
IFR CEILINGS AND REDUCED VIZ. SCATTERING IS POSSIBLE THIS AFTERNOON  
AS WINDS AND DAYTIME TEMPERATURES INCREASE. CEC REMAINS CLEAR AND  
GUSTY WITH GUSTS 25 TO 35 KNOTS POSSIBLE THIS AFTERNOON. SIMILARLY,  
UKI WILL REMAIN CLEAR WITH BREEZY WNW WINDS 10 TO 15 KNOTS. HREF  
PROBABILITIES ARE ONLY ABOUT 50% FOR IFR CEILINGS RETURNING TO ACV  
AFTER 06Z, ALTHOUGH A BROKEN <1000 FT LAYER WITH SCATTERED MIST/FOG  
IS POSSIBLE THROUGH SUNRISE. PROBABILITIES FOR <4SM VIZ ONLY ABOUT  
30% THROUGH 16Z.  
 

 
   
MARINE
 
A TIGHT COASTAL PRESSURE GRADIENT CONTINUES TO PRODUCE  
STRONG NORTHERLY WINDS. GALE GUSTS LIKELY IN THE OUTER WATERS WITH  
GUSTS 40 TO 45 KNOTS POSSIBLE IN Z470 THROUGH SATURDAY. STEEP AND  
HAZARDOUS WIND DRIVEN SEAS 12 TO 16 FEET EXPECTED IN THE OUTER  
WATERS. NEAR GALE WINDS AND STEEP SEAS 8 TO 10 FEET HAVE ALREADY  
BEEN OBSERVED ON BUOYS - THESE CONDITIONS MAY PROPAGATE INTO THE  
NORTHERN INNER WATERS, ESPECIALLY NEARSHORE OF POINT SAINT GEORGE  
AND CAPE MENDOCINO. GALE GUSTS AND STEEPEST SEAS EXPECTED TO  
RETREAT TO THE NORTHERN OUTER WATERS LATE SATURDAY INTO SUNDAY.  
WINDS AND SEAS WILL STILL REMAIN ELEVATED IN THE SOUTHERN OUTER  
WATERS, WITH THE SOUTHERN INNERS WATERS SLIGHTLY SHELTERED FROM  
THE STRONGEST WINDS AND WAVES. GALE CONDITIONS AND STEEP SEAS  
EXPECTED TO PERSIST THROUGH TUESDAY BEFORE FINALLY SHOWING SIGNS  
OF DIMINISHING MIDWEEK.  
 

 
   
FIRE WEATHER
 
BUILDING HIGH PRESSURE ALONG WITH OFFSHORE FLOW HAS  
BROUGHT WARMING AND DRYING TO THE INTERIOR AND NEAR-COASTAL AREAS.  
AFTERNOON RHS REMAIN VERY DRY, INTO THE TEENS AND 20S ACROSS MOST  
THE INTERIOR. HIGH ELEVATION AREAS (ABOVE 2000-2500 FT OR SO)  
CONTINUE TO SEE MODERATE TO POOR OVERNIGHT RH RECOVERIES. LOWER  
ELEVATIONS ARE LARGELY SEEING MODERATE TO GOOD OVERNIGHT RECOVERIES.  
OFFSHORE WINDS IN THE HIGHER TERRAIN ARE FORECAST TO REMAIN BREEZY  
OVERNIGHT, ESPECIALLY IN DEL NORTE COUNTY, THOUGH AT LEAST SUNDAY  
MORNING. SOME MARGINAL IMPROVEMENT IS POSSIBLE SUNDAY AND MONDAY  
NIGHTS, BEFORE FINALLY EASING BY TUESDAY NIGHT.  
 
UPPER-LEVEL MOISTURE ARRIVES FROM THE EAST SUNDAY AND MONDAY  
AFTERNOONS. ELEVATED INSTABILITY ALONG WITH SOME MOISTURE BRINGS A  
SLIGHT CHANCE (10-15%) FOR ISOLATED DRY THUNDERSTORMS TO NORTHERN  
TRINITY COUNTY. AS OF NOW, MOISTURE LOOKS MORE LIMITED MONDAY, BUT  
THERE IS STILL A 5-10% CHANCE FOR ISOLATED DRY THUNDERSTORMS.  
 
THE RIDGE BEGINS TO WEAKEN MONDAY INTO EARLY NEXT WEEK, WHICH WILL  
SLOWLY DEEPEN THE MARINE LAYER INTO THE MIDDLE OF NEXT WEEK. RHS  
WILL IMPROVE IN THE NEAR-COASTAL AREAS WITH MODERATE TO GOOD  
OVERNIGHT RECOVERIES POSSIBLE IN THE HIGHEST TERRAIN BY THE TUESDAY  
OR WEDNESDAY. JB  
 

 
   
EKA WATCHES/WARNINGS/ADVISORIES
 
 
CA...  
HEAT ADVISORY FROM 11 AM SATURDAY TO 11 PM PDT SUNDAY FOR  
CAZ102-105.  
 
EXTREME HEAT WARNING FROM 11 AM SATURDAY TO 11 PM PDT  
MONDAY FOR CAZ102-105.  
 
HEAT ADVISORY FROM 11 AM SATURDAY TO 11 PM PDT MONDAY FOR  
CAZ106.  
 
EXTREME HEAT WARNING UNTIL 11 PM PDT MONDAY FOR CAZ107-108.  
 
HEAT ADVISORY UNTIL 11 PM PDT SUNDAY FOR CAZ110-111-113>115.  
 
NORTHWEST CALIFORNIA COASTAL WATERS...  
HAZARDOUS SEAS WARNING UNTIL 11 AM PDT SATURDAY FOR PZZ450.  
 
GALE WARNING UNTIL 11 PM PDT SATURDAY FOR PZZ470.  
 
GALE WARNING UNTIL 11 AM PDT SATURDAY 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