016  
FXUS66 KMFR 052138  
AFDMFR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MEDFORD OR  
238 PM PDT SAT JUL 5 2025  
   
SYNOPSIS
 
 
AN UPPER LEVEL LOW WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS  
OUR FORECAST AREA BETWEEN MONDAY AND WEDNESDAY. TEMPERATURES WILL  
THEN TREND WARMER TOWARDS THE END OF THE WEEK.  
   
DISCUSSION
 
 
PLENTY OF CUMULUS BUILDUP EAST OF THE CASCADES AND ALONG THE  
CASCADES THIS AFTERNOON AS THERE IS STILL SOME LINGERING MOISTURE  
AND WEAK SYNOPTIC LIFT ACROSS THE REGION. THE WEATHER WILL REMAIN  
FAIRLY QUIET TONIGHT AS SOME COOLER TEMPERATURES IN THE MID 50'S  
SETTLE INTO MOST LOCATIONS OVERNIGHT.  
 
BY SUNDAY, A CUTOFF LOW WILL SETTLE RIGHT ALONG THE CENTRAL  
CALIFORNIA COASTLINE BY MID DAY. TEMPERATURES TREND A BIT WARMER  
WITH HIGHS IN THE MID 90'S HERE IN MEDFORD. BROOKINGS SHOULD BE ON  
THE WARMER SIDE AS WELL WITH 10 TO 15 KNOT NORTH EAST WINDS OVER  
THE SOUTHERN COASTAL RANGE. THAT WILL RESULT IN HIGHS BETWEEN THE  
MID 70'S TO PERHAPS MID 80'S OVER SPOTS IN CURRY COUNTY. WE SHOULD  
SEE MORE CUMULUS BUILDUP DURING THE DAY, ALTHOUGH WE'RE NOT  
EXPECTING ANY THUNDERSTORMS AT THIS TIME.  
 
THIS WILL CHANGE BY MONDAY AS A SMALL CHUNK(~30%) OF ECMWF ENS  
MEMBERS ARE PREDICTING SOME PRECIPITATION, WHICH SHOULD COME IN  
THE FORM OF THUNDERSTORMS GIVEN THE PATTERN AND SURFACE  
TEMPERATURES ANTICIPATED MONDAY. THE NAMNEST AND NAM SOUNDINGS  
SHOW ABOUT 400 J/KG OF CONVECTIVE AVAILABLE POTENTIAL  
ENERGY(CAPE) WITH LITTLE CONVECTIVE INHIBITION(CIN). SOME OF THESE  
STORMS COULD BE ELEVATED AND AGAIN HEDGE TOWARDS THE DRY SIDE.  
STORMS ARE ANTICIPATED TO BE ISOLATED.  
 
THE UPPER LEVEL LOW NUDGES JUST A BIT FARTHER NORTH GIVING US SOME  
PRETTY GOOD UPPER LEVEL DIVERGENCE ON TUESDAY AFTERNOON. THE  
ENVIRONMENT SHOULDN'T CHANGE MUCH FRANKLY AND THE ECMWF ENS  
MEMBERS ARE AGAIN PICKING UP ON THUNDERSTORMS A LITTLE FARTHER  
NORTH ON TUESDAY IN OUR OREGON ZONES. AGAIN, IT'S LOOKING MORE  
ISOLATED ON TUESDAY.  
 
FINALLY BY WEDNESDAY, THE UPPER LEVEL LOW BEGINS TO MOVE  
EASTWARDS AND WE SHOULD SEE SOME MORE THUNDERSTORMS AROUND THE  
REGION. LOCATIONS IN NORTHERN CALIFORNIA AND EAST OF THE CASCADES  
WILL SEE THUNDERSTORM ACTIVITY DURING THE DAY YET AGAIN.  
ESSENTIALLY, WE SHOULD SEE SOME CLOUD TO GROUND LIGHTNING  
SOMEWHERE IN OUT FORECAST AREA BETWEEN MONDAY THROUGH WEDNESDAY.  
 
AFTER THE LOW FINALLY DEPARTS THE REGION, TEMPERATURES WILL  
LIKELY WARM TOWARDS THE 100'S ON FRIDAY AND SATURDAY. IT WILL BE A  
WARM PERIOD AND THERE ARE HINTS A THERMAL TROUGH COULD BUILD OVER  
US DURING NEXT WEEKEND, WHICH USUALLY LEADS US TO SOME HOT, DRY  
AND UNSTABLE WEATHER.  
 
-SMITH  
 

 
   
AVIATION...05/18Z TAFS
 
ALL AREAS ARE VFR CURRENTLY, EXCEPT FOR A  
SMALL SLIVER OF COASTAL IFR STRATUS NEAR BROOKINGS (EVEN THERE IT  
SHOULD BREAK OUT IN THE NEXT COUPLE OF HOURS). EXPECT VFR TO PREVAIL  
ELSEWHERE THROUGH LATE THIS AFTERNOON WITH GUSTY NORTH WINDS  
DEVELOPING ALONG THE COAST (UP TO AROUND 30 KT AT NORTH BEND). OVER  
THE INTERIOR, BREEZES WON'T BE AS STRONG, BUT STILL AROUND 20 KT IN  
SOME PLACES.  
 
A SHALLOWER MARINE LAYER TONIGHT INTO SUNDAY MORNING ALONG WITH A  
SLIGHT VEERING OF THE WINDS TO NORTHEAST WILL RESULT IN A LESSER  
COVERAGE OF STRATUS, BUT LIFR WHERE IT DOES FORM (ESP, NORTH BEND).  
 
-SPILDE  
 

 
   
MARINE...UPDATED 200 PM PDT SATURDAY, JULY 5, 2025
 
WINDS WILL  
CONTINUE TO INCREASE INTO THIS EVENING AS THE THERMAL TROUGH  
REBUILDS. WINDS AND SEAS WILL BE HAZARDOUS TO SMALLER CRAFTS SOUTH  
OF CAPE BLANCO THIS EVENING. THESE HAZARDOUS CONDITIONS WILL THEN  
EXPAND NORTHWARD WITH STEEP SEAS ACROSS THE WATERS BY SUNDAY  
EVENING. HOWEVER, GALES ARE ANTICIPATED SOUTH OF PORT ORFORD BY  
SUNDAY EVENING THROUGH MONDAY. CONDITIONS IMPROVE SLIGHTLY BY  
MONDAY EVENING.  
 
-SMITH  
 

 
   
FIRE WEATHER...UPDATED 200 PM PDT SATURDAY, JULY 5, 2025
 
AN  
UPPER RIDGE WILL CONTINUE TO MOVE IN OVER THE AREA THE REMAINDER OF  
THIS WEEKEND. THIS WILL BRING DRY, STABLE CONDITIONS THE REST OF  
TODAY AND THROUGH SUNDAY WITH TEMPERATURES GETTING BACK ABOVE NORMAL  
LEVELS. A FEW FAIR-WEATHER CUMULUS ARE OUT THERE THIS AFTERNOON,  
BUT NO THUNDERSTORMS. ON SUNDAY, THERE CAN BE A FEW BUILDUPS OVER  
THE SE MOUNTAINS (WARNERS) DURING THE AFTERNOON/EVENING, BUT  
THERE DOESN'T APPEAR TO BE ENOUGH INSTABILITY/MOISTURE TO PRODUCE  
DEEP CONVECTION. AS SUCH WE'VE KEPT THUNDER OUT OF THE FORECAST.  
OTHERWISE, THE FORECAST WILL BE FOR CONTINUED NEAR TO SLIGHTLY ABOVE  
NORMAL TEMPERATURES, SEASONAL HUMIDITIES, AND THE TYPICAL DIURNAL  
WIND PATTERNS, ALTHOUGH GENERAL EAST FLOW LATE THIS WEEKEND INTO  
EARLY NEXT WEEK LEADING TO DRYING, ESPECIALLY ACROSS THE RIDGELINES,  
WHERE POOR TO MODERATE RECOVERIES ARE POSSIBLE.  
 
HEAT BUILDS FURTHER MONDAY AND TUESDAY WITH HIGH TEMPERATURES  
IN THE MID TO UPPER 90S AND EVEN SOME READINGS IN THE WEST  
SIDE/NORCAL VALLEYS EXCEEDING 100F.  
 
LOW PRESSURE WILL THEN DEVELOP OFF THE CALIFORNIA COAST SETTING UP  
JUST WEST OF SF BAY SUNDAY NIGHT INTO MONDAY. THIS IS A SIMILAR SET  
UP TO THE PATTERN THAT BROUGHT CONVECTION TO THE AREA FOR SEVERAL  
DAYS THIS PAST (LAST) WEEK. ONE DIFFERENCE THOUGH IS THAT THE DEEP  
SOUTHERLY FLOW OF MOISTURE AVAILABLE DURING THE LAST EVENT APPEARS  
TO BE LESS WITH THIS ONE AND, AS SUCH, A LIMITING FACTOR FOR  
CONVECTION. THAT SAID, LATEST GUIDANCE CONTINUES TO SHOW  
AT LEAST A SLIGHT CHANCE (15 TO <25%) OF THUNDERSTORMS EACH PM/EVE  
BEGINNING MONDAY AND CONTINUING THROUGH WEDNESDAY. NORCAL SEEMS TO  
BE FAVORED, BUT ALSO PORTIONS OF THE CASCADES AND EAST SIDE. IT  
SHOULD BE NOTED THAT MODEL PWS WITH THIS POTENTIAL CONVECTION ARE  
AROUND 0.50-0.75" (ESP SOUTHERN AND EASTERN AREAS, WHERE VALUES  
COULD BE BELOW 0.50" AT TIMES), SO ANY HIGH-BASED CONVECTION THAT  
DOES DEVELOP MIGHT NOT PRODUCE ANY RAINFALL. WE'LL CONTINUE TO  
MONITOR THE GUIDANCE TO HONE IN ON LIGHTNING POTENTIAL AND AREAS  
THAT STAND THE BEST CHANCE OVER THE COMING DAYS. THE LOW WILL GET A  
KICK ONSHORE WEDNESDAY AND MOVE THROUGH NORCAL AND INTO NW NEVADA  
DURING THE AFTERNOON/EVENING. STILL COULD BE ACTIVITY IN NORCAL AND  
EAST OF THE CASCADES THEN, BUT DO EXPECT DRIER WESTERLY FLOW TO MOVE  
IN WEDNESDAY NIGHT AND THE THUNDER RISK TO END. EXPECT SLIGHT  
COOLING WED/THU, BUT A RETURN OF HOTTER WEATHER AGAIN BY FRIDAY.  
THERE ALSO COULD BE A PERIOD OF WEAK OFFSHORE E WINDS WEDNESDAY  
NIGHT THROUGH FRIDAY MORNING.  
 
-SPILDE  
 

 
   
MFR WATCHES/WARNINGS/ADVISORIES
 
 
OR...CA...NONE.  
 
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING  
TO 8 AM PDT MONDAY FOR PZZ350-370.  
 
SMALL CRAFT ADVISORY UNTIL 8 AM PDT MONDAY FOR PZZ356-376.  
 
GALE WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING FOR PZZ356-  
376.  
 

 
 

 
 
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