128  
FXUS65 KPSR 180950  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
250 AM MST SUN JAN 18 2026  
   
UPDATE
 
12Z AVIATION DISCUSSION.  
 

 
   
KEY MESSAGES
 
 
- STRONG HIGH PRESSURE ACROSS THE REGION WILL PERSIST FOR MUCH OF  
THE COMING WEEK LEADING TO ABOVE NORMAL TEMPERATURES AND DRY  
CONDITIONS.  
 
- A BIT MORE UNSETTLED WEATHER MAY AFFECT THE REGION BY NEXT  
WEEKEND WITH RAIN CHANCES POTENTIALLY RETURNING AND  
TEMPERATURES DROPPING CLOSER TO NORMAL.  
 

 
   
SHORT TERM /TODAY THROUGH TUESDAY/
 
 
TRANQUIL WEATHER CONDITIONS WILL PREVAIL EARLY THIS WEEK AS WE  
REMAIN STUCK UNDER A BLOCKING RIDGE OF HIGH PRESSURE. THE CURRENT  
WEATHER REGIME SHOWS AN OMEGA BLOCKING PATTERN WITH RIDGING  
THROUGHOUT THE WESTERN U.S. AND SOUTHWEST CANADA AND DEEP  
TROUGHING ACROSS THE EASTERN 2/3RDS OF THE CONUS AND CANADA. THIS  
WILL CONTINUE TO PROVIDE FOR POSITIVE TEMPERATURES ANOMALIES  
ACROSS THE DESERT SOUTHWEST AND MUCH OF THE WESTERN STATES THIS  
WEEK. H5 HEIGHTS REACHING INTO THE 90TH PERCENTILE OF CLIMATOLOGY  
WILL CONTINUE ACROSS OUR REGION TODAY BEFORE LOWERING ON MONDAY.  
TEMPERATURES WILL BARELY RESPOND TO THE LOWERING HEIGHTS WITH  
HIGHS ESSENTIALLY STAYING IN A 72-76 DEGREE RANGE EARLY THIS WEEK.  
WE WILL ALSO BEGIN TO SEE SOME HIGH CLOUDS MOVE INTO THE AREA  
LATER TODAY AND LAST THROUGH MONDAY, BUT THEY WILL REMAIN QUITE  
THIN ALLOWING FOR PLENTY OF SUNSHINE BOTH DAYS. SUNNY SKIES ARE  
EXPECTED FOR TUESDAY.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SATURDAY/
 
 
UPPER LEVEL RIDGING IS FORECAST TO CONTINUE ON WEDNESDAY AND  
LIKELY INTO THURSDAY BEFORE MUCH OF THE WESTERN U.S. BEGINS TO  
FALL UNDER SOME MODEST TROUGHING BY FRIDAY. AT THE SAME TIME, A  
CUT-OFF LOW WILL DEVELOP OFF THE COAST OF CALIFORNIA WITH THE BULK  
OF THE ENSEMBLE GUIDANCE POINTING AT THIS DISTURBANCE NOT GAINING  
MUCH STRENGTH AND EVENTUALLY DRIFTING SOUTHEASTWARD BY NEXT  
WEEKEND. THE SHIFT AWAY FROM THE RIDGING LATER THIS WEEK SHOULD  
LOWER OUR TEMPERATURES MODESTLY BY FRIDAY INTO NEXT WEEKEND, BUT  
SO FAR THE NBM KEEPS OUR TEMPERATURES BARELY TOUCHING THE NORMAL  
RANGE. THE CUT-OFF LOW COULD GET CLOSE ENOUGH TO AFFECT PORTIONS  
OF OUR REGION BY NEXT WEEKEND, BUT MODEL TRENDS HAVE BEEN LEANING  
TOWARD THE SYSTEM MOSTLY BYPASSING OUR REGION TO THE SOUTH. MODELS  
HAVE A DIFFICULT TIME HANDLING THESE CUT-OFF LOWS, SO FORECAST  
CONFIDENCE REMAINS QUITE LOW FOR FRIDAY INTO NEXT WEEKEND. BETWEEN  
THE GEFS AND THE EPS, AROUND 25% OF THE MEMBERS SHOW DECENT RAIN  
CHANCES WITH THE CUT-OFF LOW. MODELS ARE NOT LIKELY TO HAVE A GOOD  
HANDLE ON THIS SYSTEM UNTIL AT LEAST THE MIDDLE OF THE WEEK.  
 

 
   
AVIATION
 
UPDATED AT 0950Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION CONCERNS ARE ANTICIPATED THROUGH THE FORECAST PERIOD.  
WINDS WILL FOLLOW TYPICAL DIURNAL TRENDS WITH SPEEDS GENERALLY AOB  
6 KT. EXTENDED PERIODS OF LIGHT AND VARIABLE TO CALM CONDITIONS  
CAN ALSO BE EXPECTED. CLEAR SKIES WILL CONTINUE THIS MORNING  
BEFORE SCT HIGH CIRRUS CLOUDS ARRIVE BY THIS AFTERNOON.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO AVIATION CONCERNS ARE EXPECTED OVER THE NEXT 24 HOURS. WINDS  
WILL REMAIN OUT OF THE W-SW AT BOTH TERMINALS BEFORE SHIFTING OUT  
OF THE NW AT KIPL AND N-NW AT KBLH EARLY THIS AFTERNOON. SCT HIGH  
CIRRUS CLOUDS WILL OVERSPREAD SE CALIFORNIA THROUGH THIS EVENING.  
 

 
   
FIRE WEATHER
 
 
STRONG HIGH PRESSURE WILL PERSIST ACROSS THE REGION OVER THE NEXT  
SEVERAL DAYS KEEPING TEMPERATURES ABOVE NORMAL AND DRY CONDITIONS  
IN PLACE. DAILY MINRH VALUES WILL REMAIN STABLE, FALLING TO  
15-20% EACH DAY WITH OVERNIGHT RECOVERIES OF 30-50%. WINDS WILL  
OVERALL BE LIGHT THROUGH THE PERIOD WITH ONLY SOME PERIODIC  
BREEZINESS ACROSS THE LOWER CO RIVER VALLEY AND OVER THE ARIZONA  
HIGH TERRAIN.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...NONE.  
CA...NONE.  

 
 

 
 
SHORT TERM...KUHLMAN  
LONG TERM...KUHLMAN  
AVIATION...SALERNO  
FIRE WEATHER...KUHLMAN  
 
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