National Weather Service Raw Text Product

000 
FXUS65 KPSR 161702
AFDPSR

AZZ020>028-CAZ030>033-162245-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1000 AM MST THU NOV 16 2000
  
.SYNOPSIS...
MOSTLY CLEAR NIGHTS AND SUNNY DAYS ARE EXPECTED THROUGH THE MIDDLE 
OF NEXT WEEK. UNSEASONABLY COOL TEMPERATURES WILL CONTINUE THROUGH 
AT LEAST SATURDAY AS A LOW PRESSURE SYSTEM AFFECTS THE AREA. BREEZY 
TO WINDY CONDITIONS WILL DEVELOP SATURDAY AS THE LOW MOVES JUST EAST 
OF ARIZONA. A WARMING TREND IS EXPECTED TO BEGIN BY EARLY NEXT WEEK 
AS HIGH PRESSURE BUILDS OVER THE WESTERN UNITED STATES. BY TUESDAY 
...DAYTIME HIGHS WILL BE MORE TYPICAL FOR THIS TIME OF YEAR. 

.DISCUSSION...
SOMEWHAT COLDER MORNING OVER THE FORECAST AREA THANKS TO COMBINATION 
OF COLD ADVECTION...LIGHT WINDS...AND DRY AIR. 500 MB HEIGHTS ARE 
120-140 M BELOW CLIMO FOR MID-NOVEMBER. MAX TEMPS OVER FORECAST AREA 
SHOULD BE NEAR 15 DEGREES BELOW NORMAL TODAY...WHICH COULD BE A FEW 
DEGRES COLDER THAN WHAT OCCURRED WEDNESDAY. WATER VAPOR LOOP 
CONFIRMS THAT A REINFORCING SHOT OF COOL AIR IS HEADED OUR WAY 
THANKS TO A COUPLE OF DISTURBANCES DROPPING SOUTH ON THE LEE SIDE OF 
HIGH AMPLITUDE EPAC RIDGE. UPPER LOW CENTERED NEAR 38.4N 128.7W HAS 
MOVED TOWARD THE SOUTH-SOUTHEAST DURING THE PAST 12 HOURS...AND 
APPEARS LIKELY TO CONTINUE THAT MOTION UNTIL IT GETS WEST OF OUR 
FORECAST AREA. FASTER-MOVING SHORT WAVE NEAR CANADA-MONTANA BORDER 
FORECAST TO BECOME NEARLY IN PHASE WITH PREVIOUSLY MENTIONED UPPER 
LOW OVER ARIZONA BY LATE FRIDAY/EARLY SATURDAY. THIS PATTERN 
SUPPORTS STRENGTHENING SURFACE HIGH PRESSURE OVER THE NORTHWEST 
UNITED STATES...WHICH IS WHAT MODELS ARE FORECASTING. BASED ON WV 
IMAGERY ...SEE NO REASON TO DOUBT THIS WILL OCCUR. MOISTURE SUPPLY 
OVER FORECAST AREA VERY LOW ATTM...WITH PRECIPITABLE WATER LESS THAN 
TWO TENTHS OF AN INCH. COULD SEE SOME INCREASE IN MAINLY MID AND 
UPPER LEVEL MOISTURE ON FRIDAY AS FLOW ALOFT BACKS SOMEWHAT...BUT 
LOW LEVEL DEW POINTS SHOULD REMAIN AT OR BELOW CLIMO. A LITTLE 
WARMER FRIDAY AS WEAK WARM ADVECTION OCCURS IN ADVANCE OF UPPER 
LOW...BUT STILL COOL FOR THIS TIME OF YEAR. EXPECT WINDY CONDITIONS 
TO DEVELOP LATE FRIDAY NIGHT OVER LOWER COLORADO RIVER VALLEY...AND 
OVER MUCH OF FORECAST AREA SATURDAY IN AREA WHERE MODERATE 
SUBSIDENCE (COLD ADVECTION AND NVA) EXPECTED TO COUPLE WITH DECENT 
PRESSURE GRADIENT BETWEEN DEPARTING LOW PRESSURE ALOFT AND RIDGING [
TO OUR WEST. WILL ADDRESS EXTENDED FORECAST IN AFTERNOON DISCUSSION. 
NO CHANGES TO CURRENT FORECAST. DG