083  
FXUS66 KMFR 101754  
AFDMFR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MEDFORD OR  
1054 AM PDT TUE JUN 10 2025  
   
UPDATED AVIATION DISCUSSION
 
 

 
   
AVIATION...10/18Z TAFS
 
ALONG THE COAST, AREAS OF IFR/LIFR  
CONDITIONS ARE GRADUALLY RETREATING BACK TO THE IMMEDIATE COAST WITH  
IMPROVEMENT TO VFR FOR COASTAL LOCATIONS EXPECTED BETWEEN 18Z & 21Z.  
THE LOWER CONDITIONS ARE LIKELY TO LINGER SOUTH OF GOLD BEACH THE  
LONGEST. VFR CONDITIONS ALONG THE COAST ARE LIKELY TO BE BRIEF, WITH  
IFR/LIFR EXPECTED TO RETURN IN THE EARLY EVENING AND CONTINUE INTO  
WEDNESDAY MORNING.  
 
VFR CONDITIONS WILL PREVAIL FOR ALL OTHER AREAS THROUGH THE TAF  
PERIOD. ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED THIS  
AFTERNOON AND EVENING SOUTH OF THE UMPQUA DIVIDE AND FROM THE  
CASCADES EAST IN SOUTHWEST OREGON AND ACROSS SISKIYOU AND MODOC  
COUNTIES IN NORTHERN CALIFORNIA. HEAVY RAIN FROM THUNDERSTORM CORES  
COULD BRIEFLY LOWER VISIBILITIES TO MVFR, BUT THE MAIN HAZARDS WITH  
THESE STORMS WILL BE STRONG AND ERRATIC OUTFLOW THUNDERSTORM WINDS  
AND LIGHTNING. HAIL IS ALSO POSSIBLE AND THERE IS A 5% CHANCE OF  
LARGE DAMAGING HAIL OF 1 INCH OR MORE DIAMETER, AND STRONG WINDS OF  
60 MPH, INCLUDING FOR MEDFORD (KMFR), KLAMATH FALLS (KLMT), MONTAGUE  
(KSIY), AND LAKEVIEW (KLKV). THE PROBABILITY OF STRONG/SEVERE  
THUNDERSTORMS, AND STORM COVERAGE WILL DIMINISH AFTER SUNSET, BUT  
THUNDERSTORM CHANCES (15-30%) WILL PERSIST LATE TONIGHT INTO EARLY  
WEDNESDAY MORNING FOR SOUTHERN KLAMATH, LAKE, NORTHEAST SISKIYOU,  
AND NORTHERN MODOC COUNTIES. -DW/BR-Y  
 

 
   
PREV DISCUSSION
 
/ISSUED 351 AM PDT TUE JUN 10 2025/  
 
DISCUSSION...TODAY WILL BE MORE ACTIVE WITH STORMS COVERING A  
LARGER PORTION OFTHE FORECAST AREA. AN UPPER TROUGH WILL APPROACH  
FROM THE WEST AND PUT THE AREA IN A FAVORABLE POSITION FOR  
ISOLATED TO SCATTERED THUNDERSTORMS ALONG AND EAST OF THE CASCADES  
AND IN NORTHERN CALIFORNIA, WITH THE INSTABILITY PARAMETERS  
GREATEST IN WESTERN SISKIYOU COUNTY, NORTHEAST INTO KLAMATH AND  
LAKE COUNTIES, AND THE SOUTHEAST PORTION OF JACKSON COUNTY.  
 
GIVEN THE POSITION OF THE UPPER TROUGH AXIS AND STRONGER TRIGGER  
AHEAD OF IT COULD BRING A HEIGHTEN THREAT FOR ISOLATED STRONG TO  
SEVERE STORMS THAT WILL PRODUCE GUSTY WINDS NEAR AND WITHING STORMS,  
AND POSSIBLE HAIL FOR THE AREAS MENTIONED ABOVE. ALSO, THE AMOUNT  
OF AVAILABLE MOISTURE WILL BE HIGHER, THEREFORE STORMS WILL HAVE  
A BETTER CHANCE OF PRODUCING LOCALLY HEAVY DOWNPOURS FOR THE SAME  
AREAS. THIS WILL INCLUDE MOST OF JACKSON COUNTY, INCLUDING  
MEDFORD, PHOENIX, TALENT, WHITE CITY, AND ASHLAND. STEERING FLOW  
WILL BE FROM THE SOUTHWEST, THEREFORE STORMS WILL TEND TO MOVE  
FROM SOUTHWEST TO NORTHEAST. HOWEVER, THE STEERING FLOW WILL BE ON  
THE LIGHT SIDE AT AROUND 10 KNOTS, THUS, STORMS MAY NOT BE QUICK  
MOVERS, INCREASING THE POSSIBILITY FOR LOCALIZED URBAN FLOODING  
IN AREAS THAT EXPERIENCE HEAVIER RAINFALL.  
 
STORMS ARE EXPECTED TO DECREASE IN COVERAGE, BUT WILL CONTINUE  
INTO THE OVERNIGHT HOURS TUESDAY NIGHT INTO EARLY WEDNESDAY  
MORNING, WITH THE UPPER TROUGH AXIS TO THE WEST. THESE ARE LIKELY  
TO BE ISOLATED AND CONFINED TO PORTIONS OF LAKE AND KLAMATH  
COUNTIES.  
 
THE UPPER TROUGH AXIS IS EXPECTED TO BE MOVE EAST OF THE FORECAST  
AREA LATER WEDNESDAY MORNING WITH A DRIER AIR MASS AND STABLE  
WESTERLY FLOW PATTERN. THE NBM AND MOST OF THE HIGH RESOLUTION  
MODELS INDICATE A DRY WEDNESDAY. BUT, THERE IS SOME SUPPORT IN  
THE GFS, HREF, AND SREF FOR A SLIGHT CHANCE OF THUNDERSTORMS TO  
POP UP WEDNESDAY AFTERNOON FROM SOUTH CENTRAL SISKIYOU COUNTY  
NORTHEASTWARD ACROSS NORTHWEST MODOC COUNTY INTO LAKE COUNTY. WE  
WILL CONTINUE TO LEAN TOWARD THE NBM FOR NOW AND REASSESS WITH THE  
12Z SUITE OF DATA. AT THE WORST, THE RISK OF STORMS STILL WOULD  
BE FAR LESS THAN THAT OF TODAY.  
 
FROM MID-WEEK, WE'LL BE HEADING INTO A PATTERN OF WEAK UPPER  
TROUGHING THAT WILL PERSIST INTO FATHERS DAY WEEKEND. THE NET  
RESULT WILL BE COOLER, MORE SEASONABLE AFTERNOON TEMPERATURES FOR  
THE INTERIOR WITH CONTINUED NIGHT AND MORNING LOW CLOUDS AND  
FOG ALONG AND NEAR THE COAST. ODDS ARE IT WILL BE DRY DURING THIS  
TIME.  
 
-PETRUCELLI/DW  
 
MARINE...UPDATED 200 AM TUESDAY, JUNE 10, 2025...HIGH PRESSURE  
OFFSHORE AND LOW PRESSURE INLAND ARE EXPECTED TO PERSIST INTO THE  
WEEKEND. THE HIGHEST SEAS ARE EXPECTED TODAY INTO TONIGHT, WITH  
SLIGHT IMPROVEMENT TO FOLLOW. THE STRONGEST WINDS AND STEEPEST SEAS  
ARE EXPECTED SOUTH OF PORT ORFORD TO AROUND PISTOL RIVER AND OUT 30  
NM FROM SHORE. SEAS WILL REMAIN DOMINATED BY A MIX OF NORTHERLY WIND  
WAVE AND FRESH SWELL, WITH STEEP SEAS ACROSS ALL OF THE SOUTHERN  
OREGON COASTAL WATERS THROUGH WEDNESDAY EVENING, THEN SOUTH OF PORT  
ORFORD AT LEAST THROUGH THURSDAY EVENING. -DW  
 
FIRE WEATHER...UPDATED 200 PM MONDAY JUNE 9, 2025...DRY AND  
MOSTLY HOT WEATHER WILL CONTINUE FOR ONE MORE DAY. THE MAIN  
CONCERN AHEAD WILL BE ISOLATED TO SCATTERED THUNDERSTORMS IN THE  
AFTERNOON AND EARLY EVENING HOURS ON TUESDAY. A STRONGER UPPER  
TROUGH WILL APPROACH FROM THE WEST, BUT THE TREND IS FOR A SLOWER  
ARRIVAL OF THE UPPER TROUGH AXIS. EVEN SO, THIS WILL PUT THE AREA  
IN A MORE FAVORABLE POSITION FOR SOME STORMS BE STRONG TO SEVERE  
SINCE THE TRIGGER IS EXPECTED TO BE STRONGER ALONG WITH GREATER  
INSTABILITY. SO FAR, GUIDANCE IS IN PRETTY GOOD AGREEMENT  
SUGGESTING STORMS WILL COVER A LARGER POTION OF THE AREA AND THE  
SHEAR NUMBER OF STORMS WILL BE HIGHER. DUE TO THE COMBINATION OF  
INSTABILITY, STRONGER TRIGGER AND FAVORABLE DYNAMICS, THERE IS  
CONCERN FOR STORMS TO PRODUCE GUSTY OUTFLOW WINDS, WITH HAIL  
POSSIBLE WITH STORMS ARE END UP STRONG TO SEVERE. THE ONE  
DIFFERENCE COMPARED TO THE LAST COUPLE OF DAYS WILL BE THE AMOUNT  
OF AVAILABLE MOISTURE. PWATS (THE AMOUNT OF MOISTURE IN A COLUMN  
WILL BE HIGHER, AND THE SUB LAYER WON'T BE AS DRY. THUS THERE  
COULD BE A HEIGHTEN CONCERN FOR LOCALLY HEAVY DOWNPOURS. THIS WILL  
INCLUDE MOST OF JACKSON COUNTY. STEERING FLOW WILL BE FROM THE  
SOUTHEAST, THEREFORE STORMS WILL TEND TO MOVE FROM SOUTHWEST TO  
NORTHEAST. HOWEVER, THE STEERING FLOW WILL BE ON THE LIGHT SIDE,  
THUS, STORMS MAY NOT BE QUICK MOVERS, THUS INCREASING THE  
POSSIBILITY FOR LOCALIZED FLOODING IN AREAS THAT EXPERIENCE  
HEAVIER RAINFALL.  
 
CURRENT FUEL CONDITIONS SUGGEST THEY COULD END UP BEING MORE  
RECEPTIVE TO NEW STARTS IF WE HAVE A SIGNIFICANT MOUNT OF LIGHTNING.  
PLEASE USE EXTRA CARE WHEN PARTICIPATING IN ACTIVITIES THAT MAY  
CREATE SPARKS OR EMBERS. THESE CAN IGNITE FIRES THAT CAN QUICKLY  
GROW OUT OF CONTROL, ESPECIALLY AROUND ABUNDANT DRY OR UNMAINTAINED  
FUELS.  
 
WITH THE SLOWER ARRIVAL OF THE UPPER TROUGH AXIS, WE COULD SEE  
ISOLATED STORMS LINGER TUESDAY NIGHT INTO WEDNESDAY MORNING, THEN  
ONCE THE UPPER TROUGH AXIS SHIFT EAST LATER WEDNESDAY MORNING, THEN  
THREAT FOR STORMS WILL SHIFT EAST OF THE AREA.  
 
WEDNESDAY INTO FATHERS DAY WEEKEND, IT WILL BE DRY WITH A COOLING  
TREND WITH UPPER TROUGHING SETTING UP RESULTING IN TEMPERATURES NEAR  
OR SLIGHTLY BELOW SEASONAL NORMS. -PETRUCELLI  
 

 
   
MFR WATCHES/WARNINGS/ADVISORIES
 
 
OR...CA...NONE.  
 
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 11 PM PDT  
THURSDAY FOR PZZ356-376.  
 
SMALL CRAFT ADVISORY UNTIL 11 PM PDT WEDNESDAY FOR PZZ350-370.  
 

 
 

 
 
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