FXUS65 KTWC 250802
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
110 AM MST FRI DEC 25 2009

.SYNOPSIS..DRY WEATHER WILL CONTINUE INTO THIS WEEKEND BUT WITH 
VARIABLE HIGH CLOUDS...COLD NIGHTS AND BELOW NORMAL HIGH 
TEMPERATURES. ANOTHER LOW PRESSURE SYSTEM WILL BRING A FEW VALLEY 
RAIN AND MOUNTAIN SNOW SHOWERS EARLY NEXT WEEK.

&&

.DISCUSSION...NOT MUCH TO DISCUSS IN THE NEAR TERM OVER SOUTHEAST 
ARIZONA...AS ACTIVITY THIS CHRISTMAS SEEMS TO BE OVER EASTERN HALF 
OF THE COUNTRY. STILL...FOCUSING HERE...TEMPERATURES AT THE TIME OF 
THIS WRITING REMAINED IN THE 30S AT ALL ASOS STATIONS. IR SATELLITE 
IMAGERY SHOWS HIGH CLOUDS OVERHEAD...WHICH WILL HELP MODERATE HOW 
LOW TEMPERATURES WILL GO TONIGHT...THOUGH MANY LOCATIONS ARE 
EXPECTED DROP BELOW FREEZING...IF NOT ALREADY THERE. WEAK RIDGING 
WILL REMAIN OVER THE STATE FOR THE HOLIDAY AND INTO THE WEEKEND 
BEFORE MOVING EAST MONDAY.

FORECAST PROBLEM COMES WITH UPCOMING SYSTEM FOR THE START OF NEXT 
WEEK. CURRENT GFS SOLUTION DIPS THE SYSTEM FURTHER SOUTH LATE MONDAY 
INTO TUESDAY. SHOULD THIS SOLUTION PROVE CORRECT...INHERITED POPS 
WOULD SEEM TO BE TOO HIGH. HOWEVER...GIVEN THE CONTINUED UNCERTAINTY 
IN THE TRACK OF THIS STORM...AS THIS SOLUTION IS FURTHER SOUTH THAN 
WHAT WAS SEEN IN RUNS 24 HOURS AGO...WILL ONLY TRIM POPS SLIGHTLY. 
WHATEVER TRACK THIS SYSTEM TAKES...DOES NOT LOOK LIKE IT WILL LINGER 
LONG...AS RIDGING LOOKS TO BUILD BACK IN FOR WEDS AND REMAIN IN 
PLACE INTO THE NEW YEAR.

ALL THAT SAID...NOT PLANNING THAT MUCH CHANGE TO FORECAST. WILL 
LIKELY TRIM POPS SLIGHTLY FOR THE MON-TUES TIME FRAME...BUT 
OTHERWISE...REMAINDER OF FORECAST LOOKS GOOD.

&&

.AVIATION...PATCHES OF CIRRUS LEVEL MOISTURE WITH SURFACE WINDS 
GENERALLY LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF 
AMENDMENTS.

&&

.FIRE WEATHER...NO FIRE WEATHER CONCERNS AT THIS TIME.
 
&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

$$

WEATHER.GOV/TUCSON