000 FXUS65 KPSR 210923 AFDPSR AZZ020>028-CAZ030>033-211745- SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 220 AM MST TUE MAY 21 2002 .SYNOPSIS... A COLD FRONT WILL BRING NOTICEABLY COOLER DAYTIME HIGHS TO SOUTHWEST ARIZONA TODAY...WITH A BIT COOLER TEMPERATURES OVER FAR SOUTHEAST CALIFORNIA. IT WILL BE BREEZY TODAY...BUT WINDS WILL NOT BE AS STRONG AS WHAT OCCURRED ON MONDAY. AFTER A RATHER COOL MORNING ON WEDNESDAY...A SLOW WARMING TREND WILL OCCUR THROUGH SATURDAY...WITH A RETURN TO NEAR NORMAL DAYTIME HIGHS OVER THE MEMORIAL DAY WEEKEND. .DISCUSSION... RATHER STRONG COLD FRONT SWEEPING ACROSS THE AREA THIS MORNING. ..SO IDEA OF NOTICEABLY COOLER DAYTIME HIGHS OVER SOUTHWEST AND SOUTH CENTRAL AZ TODAY LOOKS GOOD. AS OF 2 AM...TEMPS RANGED FROM THE LOWER 70S AT PHOENIX TO THE LOW 60S AT BLYTHE/YUMA/IMPERIAL... AND 24 HR CHANGES WERE ON THE ORDER OF -7 TO -12 DEGREES. SFC DEW POINTS ALSO LOWER BY 5 TO 10 DEGREES. HIGH TEMPS MOST AREAS TODAY WILL BE 10-12 DEGREES BELOW NORMAL. AS OF 2 AM...WINDS HAD DROPPED BELOW ADVISORY LEVELS OVER FAR SOUTHEAST CALIFORNIA AND ALONG THE LOWER COLORADO RIVER...SO WIND ADVISORY FOR THAT AREA WAS CANCELLED AT 1 AM. STILL BREEZY AS UPPER JET STREAK AND ASSOCIATED CIRRIFORM CLOUD STREAK PROPAGATES ACROSS WESTERN AZ...BUT GRADIENTS FORECAST TO WEAKEN DURING THE DAY AS FRONT PUSHES EAST AND WEAKENS...SO BREEZY WORDING SHOULD SUFFICE FOR MOST AREAS. WITH MOSTLY CLEAR SKIES...DRY CONDITIONS...AND LIGHT WINDS... OVERNIGHT LOWS TUESDAY NIGHT/WEDNESDAY MORNING WILL BE THE COOLEST MOST OF THE FORECAST AREA HAS SEEN SINCE THE FIRST WEEK OF MAY...MAINLY IN THE 50S OVER THE LOWER DESERT. SLOW DAY-TO-DAY WARMUP COMMENCES WEDNESDAY AND CONTINUES THROUGH UPCOMING WEEKEND ...WITH RATE OF WARMUP MITIGATED BY FACT THAT THE FORECAST AREA WILL REMAIN UNDER CYCLONIC FLOW/TROUGHING AND BELOW NORMAL 500 MB HEIGHTS NEXT FEW DAYS. 500 MB HEIGHTS FORECAST TO REBOUND TO NEAR CLIMO BY SATURDAY BY ALL EXTENDED MODELS...BUT LONG WAVE PATTERN STILL DOMINATED BY EAST U.S. RIDGE AND EPAC TROF...WHICH SUPPORTS IDEA OF TEMPS REBOUNDING TO ONLY NEAR OR SLIGHTLY ABOVE NORMAL LEVELS THIS WEEKEND AND EARLY NEXT WEEK. WILL LIKELY SEE SOME HIGH CLOUDS FROM TIME TO TIME WITH THIS REGIME IN PLACE...SO MOSTLY CLEAR WORDING APPEARS TO BE A GOOD WAY TO GO FOR MOST OF THE UPCOMING 7 DAYS. NO PRECIP EXPECTED THE NEXT 7 DAYS...WHICH IS TYPICAL FOR THIS TIME OF YEAR...AND LOW LEVEL MOISTURE/SURFACE RELATIVE HUMIDITY WILL CONTINUE TO BE A BIT BELOW NORMAL. DG .PSR...NONE.