697  
FXUS66 KMFR 262101  
AFDMFR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MEDFORD OR  
201 PM PDT FRI JUL 26 2024  
   
DISCUSSION
 
SEASONAL TEMPERATURES CONTINUE ACROSS NORTHERN  
CALIFORNIA AND SOUTHERN OREGON THIS AFTERNOON. AN UPPER TROUGH  
REMAINING IN PLACE OVER CANADA AND THE NORTHWESTERN US IS HELPING TO  
MODERATE TEMPERATURES IN THE SHORT-TERM.  
 
WILDFIRE SMOKE IS GOING TO BE A SIGNIFICANT CONCERN FOR THE  
FORESEEABLE FUTURE. THE PARK FIRE IN THE SIERRA NEVADA FOOTHILLS,  
THE CLUSTER OF FIRES IN EASTERN DOUGLAS COUNTY, AND THE FALLS FIRE  
AND THE BATTLE MOUNTAIN COMPLEX TO THE NORTHEAST ARE ALL POSSIBLE  
SOURCES OF SMOKE FOR THE AREA. LIGHT NIGHTTIME WINDS ALLOW FOR SMOKE  
TO ACCUMULATE AROUND A FIRE AND SPREAD OUT, WHILE STRONGER AFTERNOON  
WINDS CAN GUIDE A SMOKE PLUME OVER A LOCALIZED AREA. THIS AFTERNOON,  
THE PARK FIRE PLUME CONTINUES TO MOVE OVER LAKE AND MODOC COUNTIES  
BUT OVERNIGHT WIND CHANCES NEAR THE FIRE MAY PUSH THE PLUME TO THE  
EAST AND BRING SOME RELIEF. HOWEVER, LIGHTER WINDS WILL ALLOW SMOKE  
FROM THE DOUGLAS COUNTY FIRES TO SPREAD OVER AREAS EAST OF THE  
CASCADES. AN AIR QUALITY ALERT IS IN PLACE FOR KLAMATH AND LAKE  
COUNTIES THROUGH MONDAY AT NOON. INTERMITTENT SMOKE IS EXPECTED IN  
JACKSON, JOSEPHINE, AND EASTERN DOUGLAS COUNTIES. SMOKE ACCUMULATION  
BEYOND THE ALERT'S TIMEFRAME WILL BE POSSIBLE AS THESE FIRES  
CONTINUE.  
 
PRECIPITATION LOOKS UNLIKELY THROUGH THE FORECAST PERIOD. THERE ARE  
SOME SLIGHT 10% THUNDERSTORM CHANCES OVER SOUTHERN LAKE COUNTY AND 5-  
10% CHANCES OVER KLAMATH COUNTY AND ALONG THE CALIFORNIA BORDER.  
EXPECTED DRY AIR ALOFT MAKES SUBSTANTIAL RAINFALL LOOK UNLIKELY.  
THAT MAKES THESE STORMS MORE OF A CONCERN FOR LIGHTNING STRIKES, AND  
THUNDERSTORM POSSIBILITY WILL BE CONSIDERED CLOSELY DURING FUTURE  
ANALYSIS. AN ADDITIONAL CONSIDERATION FOR PRECIPITATION WILL BE A WEAK  
COLD FRONT THAT WILL MOVE OVER THE AREA FROM MONDAY AFTERNOON TO  
TUESDAY AFTERNOON. CURRENTLY THE CHANCES OF RAINFALL ARE 15-25%  
ALONG THE OREGON COAST AND EASTERN DOUGLAS COUNTY, WITH  
PRECIPITATION AMOUNTS LESS THAN 0.1 INCHES EXPECTED WHERE RAINFALL  
DOES OCCUR.  
 
LONG-TERM GUIDANCE SHOWS AN UPPER RIDGE DEVELOPING IN THE WAKE OF  
TUESDAY'S WEAK TROUGH. TEMPERATURES WILL WARM QUICKLY THROUGH  
WEDNESDAY AND THURSDAY AND ARE FORECAST TO REMAIN WARM THROUGH NEXT  
WEEKEND. BROADLY, TEMPERATURES RISE TO THE HIGH 90S TO LOW 100S FOR  
WEST SIDE VALLEYS AND LOW TO MID 90S FOR AREAS EAST OF THE CASCADES.  
THIS IS MOVING TOWARDS A RETURN OF HEAT PRODUCTS, ESPECIALLY FOR  
WEST SIDE VALLEYS, BY NEXT WEEKEND. HEATRISK GUIDANCE CURRENTLY CUTS  
OFF ON AUGUST 1ST AND DOES NOT INDICATE ANY MAJOR OR EXTREME HEAT  
THROUGH THAT DAY, BUT A TREND TOWARDS INCREASING HEAT IMPACTS IS  
CLEAR IN THE GUIDANCE THAT IS AVAILABLE. -TAD  
 
TODAY WE CELEBRATE THE RETIREMENT OF KEN SARGEANT, THE INFORMATION  
TECHNOLOGY OFFICER FOR MEDFORD SINCE 2002. KEN'S CAREER STARTED AT  
SANTA MARIA, CA IN 1993 AND HAS ALSO INCLUDED TIME AS A SENIOR  
FORECASTER IN ELKO, NV. KEN HAS BEEN AT THE FOREFRONT OF NWS  
ADVANCEMENTS, INCLUDING THE DEPLOYMENT OF DOPPER RADAR AND BEING ONE  
OF THE FIRST GROUP OF ITOS. AS MEDFORD'S ITO, KEN HAS MADE SURE THAT  
WE HAVE THE RIGHT SOFTWARE TO PROVIDE THE BEST FORECASTS TO THE  
PUBLIC. WHEN THINGS AREN'T WORKING, HE'S BEEN QUICK TO DIAGNOSE AND  
FIX THE PROBLEM (AFTER TURNING IT OFF THEN ON AGAIN, OF COURSE).  
WE'VE BEEN FORTUNATE TO HAVE BOTH HIS SUPPORT AND HIS COMPANY HERE  
AT THE MEDFORD WFO, AND WE WISH HIM ALL THE BEST IN THE PEACE AND  
QUIET THAT AWAITS HIM AND HIS FAMILY.  
 

 
   
AVIATION...26/18Z TAFS
 
WIDESPREAD VFR ACROSS THE AREA EARLY THIS  
MORNING. AREAS OF IFR/LIFR STRATUS/FOG HAVE ALMOST FULLY ERODED  
FROM THE COAST, BUT DO STILL LINGER AROUND BROOKINGS.  
 
IN THE IMMEDIATE VICINITY OF THE FIRES, VISIBILITY MAY BE REDUCED TO  
IFR AT TIMES, BUT AS WEST WINDS INCREASE THIS AFTERNOON AND MIXING  
IMPROVES, MUCH OF IT WILL BE LOFTED, IMPROVING VISIBILITY. SMOKE IS  
EXPECTED THIS EVENING AT KLAMATH FALLS, TO A LESSER EXTENT AT  
MEDFORD AND UNLIKELY AT ROSEBURG, THOUGH THERE MAY BE OCCASIONAL  
HAZY SKIES ACROSS MOST AREAS. ONE AREA WHERE PERSISTENT SMOKE MAY BE  
A PROBLEM ALL DAY IS IN SOUTHEAST SISKIYOU AND SOUTHERN MODOC  
COUNTIES, WHERE SMOKE MODELS INDICATE VISIBILITY COULD REMAIN AT OR  
BELOW 3 MILES DUE TO SMOKE FROM THE PARK FIRE.  
 
IFR/LIFR MARINE STRATUS/FOG AT NORTH BEND IS EXPECTED TO RETURN THIS  
EVENING AROUND 03Z. -MILES  
 

 
   
MARINE...UPDATED 200 PM FRIDAY, JULY 26, 2024
 
A THERMAL TROUGH  
WILL REMAIN IN PLACE THROUGH SATURDAY EVENING WITH NORTH WINDS AND  
STEEP TO VERY STEEP SEAS, HIGHEST FROM GOLD BEACH SOUTHWARD. WINDS  
TREND SLIGHTLY LOWER TONIGHT INTO SATURDAY, BUT STEEP SEAS LINGER,  
ESPECIALLY SOUTH OF CAPE BLANCO. THE THERMAL TROUGH WILL WEAKEN WITH  
WINDS AND SEAS GRADUALLY DIMINISHING SATURDAY NIGHT AS A WEAK FRONT  
BRINGS SOUTH WINDS MONDAY INTO TUESDAY. CALMER CONDITIONS ARE  
EXPECTED SUNDAY INTO EARLY NEXT WEEK. -SPILDE/MILES  
 

 
   
FIRE WEATHER...ISSUED 200 PM FRIDAY JULY 26, 2024
 
AN UPPER  
TROUGH WILL CONTINUE TO MOVE THROUGH WESTERN CANADA AND THIS WILL  
INCREASE MID-LEVEL FLOW AREA-WIDE TODAY. MEANWHILE, A MID-LEVEL  
WEAK LOW WILL PUSH NORTHWARD OVER OUR RIDGE OF HIGH PRESSURE TODAY  
THROUGH SUNDAY. AS A RESULT, WE ARE EXPECTING SOME GUSTY WEST TO  
SOUTHWEST WINDS OF 15 TO 20 MPH WITH GUSTS TO 30 MPH TO DEVELOP  
THIS AFTERNOON/EVENING OVER THE EASTSIDE. GIVEN THE DRY RH VALUES  
DROPPING DOWN INTO THE TEENS AND SINGLE DIGITS, HAVE ISSUED  
ANOTHER RED FLAG WARNING FOR STRONG GUSTY WINDS AND LOW RH FOR  
SOUTHEASTERN OREGON FIRE ZONE 625, SOUTHERN OREGON FIRE ZONE 625,  
AND NORTH CENTRAL CALIFORNIA FIRE ZONE 285 FROM 2PM UNTIL 8PM  
TONIGHT.  
 
IN ADDITION, THIS LOW COULD BRING AN ISOLATED SHOWER OR  
THUNDERSTORM TO AREAS ALONG AND EAST OF THE WARNER MOUNTAINS IN  
MODOC AND LAKE COUNTIES SATURDAY MORNING THROUGH SATURDAY EVENING.  
IN GENERAL, DO NOT THINK THIS PATTERN WILL RISE TO THE LEVEL OF  
MEETING CRITICAL CONDITIONS FOR SCATTERED THUNDERSTORMS, SO NO  
PRODUCTS ARE EXPECTED AT THIS POINT.  
 
OTHERWISE FOR THIS WEEKEND AND EARLY NEXT WEEK, EXPECT TYPICAL  
AFTERNOON BREEZES AND WARM AND DRY CONDITIONS TO PERSIST, ALTHOUGH  
TEMPERATURES WILL COOL SLIGHTLY TO NEAR OR SLIGHTLY BELOW NORMAL  
VALUES FOR THIS TIME OF YEAR. THIS MEANS THAT NEAR CRITICAL WINDS  
AND HUMIDITY VALUES WILL BE POSSIBLE.  
 
MID WEEK, ANOTHER LOW PUSHES THROUGH WHICH COULD BRING SOME LIGHT  
RAIN TO THE OREGON COAST AND CASCADES, BUT CHANCES ARE THAT THIS  
RAINFALL WILL NOT BE WETTING. MORE LIKELY IS THAT THIS SYSTEM WILL  
BRING ABOUT STRONGER WINDS, BUT ALSO HIGHER HUMIDITIES FOR A  
LITTLE WHILE AS WELL. -SCHAAF  
 

 
   
MFR WATCHES/WARNINGS/ADVISORIES
 
 
OR...RED FLAG WARNING UNTIL 8 PM PDT THIS EVENING FOR ORZ624-625.  
 
CA...RED FLAG WARNING UNTIL 8 PM PDT THIS EVENING FOR CAZ285.  
 
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 11 AM PDT  
SATURDAY FOR PZZ350-370.  
 
SMALL CRAFT ADVISORY UNTIL 5 AM PDT SUNDAY FOR PZZ356-376.  
 
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ356-  
376.  
 

 
 

 
 
TAD/BPN/MCB  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab OR Page
The Nexlab CA Page Main Text Page