795  
FXUS65 KPSR 161733  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1033 AM MST MON MAR 16 2026  
   
UPDATE  
UPDATED 18Z AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- PERSISTENT HIGH PRESSURE WILL HELP KEEP TEMPERATURES RUNNING  
ABOVE NORMAL THROUGH THE START OF THE WORKWEEK.  
 
- FURTHER STRENGTHENING OF THE HIGH WILL RESULT IN AN  
UNPRECEDENTED HEAT WAVE FOR MARCH WITH WIDESPREAD TRIPLE DIGITS  
EXPECTED BY WEDNESDAY, AND WIDESPREAD READINGS NEAR 105 DEGREES  
BY THURSDAY, SHATTERING DAILY RECORDS BY AS MUCH AS 10 DEGREES.  
 
- AN EXTREME HEAT WATCH IS IN EFFECT FOR THE MIDDLE PORTION OF THE  
WEEK INTO THE WEEKEND FOR MUCH OF SOUTHEAST CALIFORNIA AND  
SOUTHERN ARIZONA  
 
 
 
   
SHORT TERM /TODAY THROUGH TUESDAY/  
 
EARLY MORNING ANALYSIS REVEALS THE HIGH THAT HAS BEEN MEANDERING OFF  
THE PACIFIC COAST STARTING TO NUDGE CLOSER INLAND WHILE THE  
TRANSIENT TROUGH THAT PASSED BY THIS WEEKEND MOVING EAST OF THE  
CENTRAL PLAINS. WITH THAT TROUGH NOW OUT OF THE REGIONAL PICTURE,  
MUCH OF THE WESTERN CONUS WILL EXPERIENCE GENERALLY QUIET CONDITIONS  
DURING THE UPCOMING WORKWEEK AS THAT EASTERN PACIFIC HIGH BECOMES  
THE DOMINANT FEATURE, DEFLECTING ANY SIGNIFICANT STORM SYSTEMS  
OFF TO OUR NORTH. IT WILL TAKE A BIT OF TIME FOR THE RIDGE TO  
REBUILD ENOUGH TO PRODUCE ANY SIGNIFICANT TEMPERATURES CHANGES  
OVER OUR FORECAST AREA, SO HIGHS THIS AFTERNOON WILL BE BASICALLY  
THE SAME AS SUNDAY WITH READINGS FOR THE LOWER DESERTS IN THE  
LOWER TO MIDDLE 90S. TUESDAY IS WHEN A MORE NOTABLE BUMP IN TEMPS  
TAKES PLACE AS THE HIGH FINALLY MAKES ITS WAY ON SHORE, PUSHING  
THE WARMEST AIR FURTHER EASTWARD. HIGHS THEN WILL RANGE GENERALLY  
IN THE MIDDLE TO UPPER 90S, WITH A FEW SPOTS, MAINLY AROUND THE  
COLORADO RIVER VALLEY AND WESTWARD, POTENTIALLY HITTING TRIPLE  
DIGITS.  
 
DUE TO THE INTENSITY OF THE PREVIOUSLY MENTIONED RIDGE AND CENTRAL  
PLAINS TROUGH, THE REGIONAL PRESSURE GRADIENT WILL STILL BE TIGHT  
ENOUGH TO PRODUCE SOME LINGERING BREEZY CONDITIONS TODAY. THE  
STRONGEST GUSTS (25-35 MPH) WILL ONCE AGAIN BE FOCUSED AROUND THE  
LOWER COLORADO RIVER VALLEY, WITH LOCALLY HIGHER GUSTS POSSIBLE  
OVER HIGHER RIDGE TOP AREAS. OTHER HIGHER TERRAIN SPOTS, SUCH AS  
JOSHUA TREE NP AND AREAS OF SOUTH-CENTRAL ARIZONA, MAY SHOULD ALSO  
ANTICIPATE SOME MARGINAL BREEZES, BUT PEAK GUSTS FOR THESE  
LOCATIONS SHOULD HOVER CLOSER TO 25 MPH.  
 
 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/  
 
BY WEDNESDAY, THE DESERT SOUTHWEST WILL FIND ITSELF DIRECTLY UNDER  
THE CENTER OF THE HIGH, WITH HEIGHTS ALOFT REACHING UPWARDS OF 592-  
594DM. TO PUT THINGS INTO PERSPECTIVE, SOUNDING CLIMATOLOGY DATA  
FOR LAS VEGAS, FLAGSTAFF, AND TUCSON SHOW RECORD H5 HEIGHTS FOR  
MARCH ARE AROUND 590DM AND APRIL 591DM, 593DM, AND 592DM  
RESPECTIVELY. THAT WOULD PUT THIS RIDGE AS ONE OF THE STRONGEST  
EVER SEEN IN RECORDED HISTORY FOR THE REGION, NOT ONLY FOR MARCH,  
BUT FOR APRIL AS WELL. WITH THIS SETUP, THE THERMAL PROFILE WILL  
ALSO APPROACH RECORD LEVELS, WITH ALL-TIME READINGS FOR MARCH  
LOOKING LIKELY AT THE H7 AND H5 LEVELS. 850MB TEMPS WILL BE CLOSE  
TO ALL-TIME MARCH RECORDS BY THIS POINT, HELPING TO PUSH  
TEMPERATURES AT THE SURFACE INTO THE TRIPLE DIGITS FOR MOST OF THE  
LOWER DESERTS. THE FORECASTED HIGH FOR PHOENIX ON WEDNESDAY IS  
102 DEGREES, WHICH IF ACHIEVED, WOULD BECOME THE EARLY INSTANCE  
OF TRIPLE DIGITS FOR THE STATION, BESTING THE PREVIOUS EARLIEST,  
WHICH IS MARCH 26TH, BY 8 DAYS. MARCH 26TH, 1988 IS ACTUALLY THE  
ONLY MARCH DATE ON RECORD WHERE 100 DEGREES WAS ACHIEVED IS  
PHOENIX, BUT APPEARS VERY LIKELY THAT MORE DAYS WILL BE ADDED TO  
THAT LIST.  
 
MODEL GUIDANCE HAS THE RIDGE STRENGTHENING EVEN FURTHER BY THURSDAY  
WITH HEIGHTS APPROACHING 594-596DM, EASILY MAKING THIS FEATURE ONE  
OF THE STRONGEST EVER SEEN DURING THIS TIME OF YEAR. THIS WILL PUSH  
TEMPERATURES INTO UNCHARTED TERRITORY (AT LEAST BY LATE WINTER AND  
EARLY SPRING STANDARDS), BOTH AT THE SURFACE AND THROUGHOUT THE  
ATMOSPHERIC COLUMN. HIGHS THURSDAY THROUGH AT LEAST SATURDAY WILL  
RANGE BETWEEN 103-109 DEGREES, WITH EVEN A LOW END CHANCE FOR A  
FEW LOCATIONS TO REACH 110F DURING THIS WINDOW. THIS WOULD PUT  
DAILY MAXTS 25-30 DEGREES ABOVE NORMAL AND DAILY RECORDS MAY BE  
BROKEN BY 5-10 DEGREES. ON THE TOPIC OF RECORDS, THIS HEAT WAVE  
ALSO PUTS MONTHLY ALL-TIME TEMPERATURES IN JEOPARDY, AS THE  
VALUES CURRENTLY STAND AT 100, 102, AND 101 FOR PHOENIX, YUMA, AND  
EL CENTRO RESPECTIVELY. ALL OF THOSE VALUES COULD BE TIED OR  
ECLIPSED AS EARLY AS WEDNESDAY, BUT IF NOT BY THEN, THEY ALMOST  
CERTAINLY WILL FALL SOMETIME BETWEEN THE END OF THE WEEK AND INTO  
THE WEEKEND.  
 
MODERATE HEATRISK WILL DEVELOP IN RESPONSE TO THE UPCOMING ABNORMAL  
HEAT, WITH EVEN SOME LOCALIZED AREAS OF MAJOR HEATRISK NOT OUT OF  
THE QUESTION. THEREFORE, AN EXTREME HEAT WATCH HAS BEEN ISSUED FOR  
THE LOWER COLORADO RIVER VALLEY AND WESTWARD FOR WEDNESDAY, WHICH  
WILL EXPAND TO INCLUDE MUCH OF SOUTHERN ARIZONA BY THURSDAY. IF  
THIS WATCH WERE TO BE UPGRADED TO A EXTREME HEAT WARNING, WHICH  
ALMOST CERTAIN AT THIS POINT, IT WOULD BECOME THE EARLIEST HEAT  
WARNING TO GO INTO EFFECT, WITH THE CURRENT EARLIEST INSTANCE  
OCCURRING BETWEEN APRIL 26TH AND 30TH OF 2020.  
 
 
   
AVIATION  
UPDATED AT 1730Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT; AND  
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
 
NO SIGNIFICANT WEATHER ISSUES WILL EXIST THROUGH MONDAY NIGHT UNDER  
THIN, HIGH CIRRUS DECKS. CONFIDENCE IS GOOD THAT WIND TRENDS WILL  
TEND TO FOLLOW THEIR TYPICAL DIURNAL TENDENCIES ACROSS THE  
PHOENIX METRO. SPEEDS WILL GENERALLY BE AOB 10 KT, BUT SOME  
OCCASIONAL GUSTS INTO THE TEENS ARE POSSIBLE THIS AFTERNOON. A  
SLIGHTLY EARLIER SWITCH TO EASTERLY IS ANTICIPATED THIS EVENING,  
AROUND 02-04Z. NORTH WINDS WILL BE FAVORED OVER SE CALIFORNIA  
WITH LIGHT NOCTURNAL WESTERLIES AT KIPL AND AFTERNOON GUSTS  
20-30KT COMMON AT KBLH.  
 
 
   
FIRE WEATHER  
 
HIGH PRESSURE WILL RESULT IN TEMPERATURES 10-15 DEGREES ABOVE NORMAL  
TODAY BEFORE INCREASING TO 25-30 DEGREES ABOVE NORMAL BY THE  
MIDDLE PORTION OF THE WEEK. ABNORMALLY HOT AND VERY DRY  
CONDITIONS WILL TRANSLATE TO MINRH NEAR 10% THE NEXT FEW  
AFTERNOONS BEFORE READINGS DROP CLOSER TO 5-10% BY WEDNESDAY.  
OVERNIGHT RECOVERIES WILL FOLLOW A SIMILAR DOWNTREND WITH VALUES  
20-40% THROUGH WEDNESDAY MORNING, DROPPING TO 15-35% THROUGH THE  
REMAINDER OF THE WEEK. BREEZY TO LOCALLY WINDY CONDITIONS WILL  
ONCE AGAIN BE OBSERVED TODAY, MAINLY OVER THE ARIZONA HIGH TERRAIN  
AND THE LOWER COLORADO RIVER VALLEY, WITH THE STRONGEST GUSTS  
(25-35 MPH) FOCUSED OVER THE LATTER AREA. THE BREEZY CONDITIONS,  
COMBINED WITH LOW RH VALUES WILL RESULT IN ELEVATED TO ISOLATED  
AREAS OF CRITICAL FIRE WEATHER CONDITIONS. HOWEVER, WITH THE  
LIMITED SCOPE OF ENHANCED WINDS, NO FIRE WEATHER PRODUCTS ARE  
NEEDED AT THIS TIME.  
 
 
 
CLIMATE...  
 
DAILY RECORD HIGHS THROUGH NEXT WEEKEND:  
 
DATE PHOENIX YUMA EL CENTRO  
---- ------- ---- ---------  
3/16 99 IN 2007 99 IN 2007 100 IN 2007  
3/17 99 IN 2007 101 IN 2007 101 IN 2007  
3/18 95 IN 2017 96 IN 2017 95 IN 2007  
3/19 96 IN 2017 98 IN 2017 96 IN 2017  
3/20 96 IN 2017 99 IN 2004 98 IN 2004  
3/21 97 IN 2004 102 IN 2004 100 IN 2004  
3/22 94 IN 1990 98 IN 2004 96 IN 2004  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...EXTREME HEAT WATCH FROM WEDNESDAY MORNING THROUGH SUNDAY EVENING  
FOR AZZ530.  
 
EXTREME HEAT WATCH FROM THURSDAY MORNING THROUGH SUNDAY EVENING  
FOR AZZ531>544-546-548>551-553>555-559.  
 
CA...EXTREME HEAT WATCH FROM WEDNESDAY MORNING THROUGH SUNDAY EVENING  
FOR CAZ561>570.  
 
 
 
 
 
SHORT TERM...RW  
LONG TERM...RW  
AVIATION...BERISLAVICH  
FIRE WEATHER...RW  
CLIMATE...18/KUHLMAN  
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