[AZ-Observing] Weather next week

     The Phoenix NWS weather office forecaster who signs himself 'Vasquez'
often seems to show up in the daily forecast discussions when something
interesting is about to happen.  In the 3am Friday morning discussion,
he notes that the upcoming storm, which has already been forecast for couple
of weeks as occurring roughly next Wednesday, bears strong resemblance to
an event from February 1993.  Some excerpts:


SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ 
245 AM MST FRI FEB 7 2003

     ...THE PATTERN IS LOOKING GOOD FOR INCREASING PRECIPITATION IN SOUTHERN 
AZ THE NEXT 7 DAYS. A SATURDAY SYSTEM...THEN WOW!...NEXT WED AND THU.

     ...HOWEVER THE 
POTENTIAL FOR EXCESSIVE RAINFALL WITH A SUBTROPICAL FEED WED AND THU 
IS LOOKING BETTER ALL THE TIME. LET US EXPLAIN.

...A 25-40 KT 850 MB JET ADVECTS A TREMENDOUS AMOUNT OF LOW 
LEVEL MOISTURE INTO ARIZONA FROM THE SUBTROPICAL REGION SOUTHWEST OF 
BAJA. IN FACT...850 MB DEWPOINTS OF 8 AND 10 DEGREES (SUMMER MONSOON 
LEVELS) MOVE AS FAR NORTH AS THE UTAH BORDER.  STRONG SOUTHERLY 
UPSLOPE WINDS (40 KNOTS AT 700 MB) WED NIGHT...ALONG WITH MID LEVEL 
DYNAMICS...INCREASE THE POTENTIAL FOR EXCESSIVE RAINFALL. 
HISTORICALLY WE REMEMBER A SYSTEM BACK ON FEB 19 1993. THIS SYSTEM 
WAS COLDER...BUT NEVERTHELESS ADVECTED UPSLOPE 850 MB DEWPOINTS OF 8C.
THE FEB 1993 STORM PRODUCED 5.50 INCHES OF RAINFALL IN FLAGSTAFF 
OVER 3 DAYS.


     My nighttime cloudiness records, which go back to 1978, often also note
significant weather events.  Indeed for February 1993 I have added a comment
on the 19th that we had all-time record rains and 10cm of snow.  (There were
25 cloudy nights in that 28-day February.)
     Might be time get pull out your hip-waders.

\Brian
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