FXUS63 KDMX 152326 AAA
AFDDMX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
525 PM CST TUE DEC 15 2009

...UPDATED 16/00Z AVIATION DISCUSSION...

.SHORT TERM /TONIGHT/...
SFC RIDGE OVER MISSOURI RIVER VALLEY WILL SLIDE SOUTH OF IOWA 
TONIGHT WITH WAA BEGINNING AFTER MIDNIGHT ACRS THE WEST.  WL SEE 
LOWS IN MOST LOCATIONS THIS EVENING...EXCEPT POSSIBLY FAR NORTHEAST 
AREAS NEAR WATERLOO WHERE CALM WINDS MAY KEEP READINGS LOW THROUGH 
SUNRISE.  HAVE CHOSEN A NON-DIURNAL CURVE WITH SOUTH WINDS 
INCREASING...ESPECIALLY WEST OF I35 AFTER MIDNIGHT.  WIND CHILLS 
WILL BE IN THE TEENS BELOW ZERO OR ABOUT 10 DEGREES WARMER THAN LAST 
NIGHT AND ADVISORY WILL NOT BE NEEDED.  

.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
LONG RANGE FORECAST REMAINS FAIRLY QUIET WITH A FEW WEAK SYSTEMS 
EXPECTED TO MOVE THROUGH THE AREA AND BRING SOME CHANCES FOR LIGHT 
SNOW. MODELS IN SOME DISAGREEMENT WITH SMALLER FEATURES TOWARD THE 
MID/LONG RANGES...BUT OVERALL ARE ALL DEPICTING BROAD TROUGHING 
ACROSS THE CENTRAL/EASTERN US WITH A TREND TOWARD COLDER 
TEMPERATURES TOWARD EARLY NEXT WEEK. 

INITIALLY TUESDAY INTO WEDNESDAY...TEMPERATURES SHOULD TREND WARMER 
BEHIND A WARM FRONT EXPECTED TO MOVE THROUGH THE CWA LATE TONIGHT 
INTO EARLY WEDNESDAY. DRY CONDITIONS EXPECTED...BUT COULD SEE AN 
INCREASE IN CLOUD COVER WITH THE WAA. A WEAK SHORTWAVE TROUGH TO DIG 
SOUTHEASTWARD ACROSS THE AREA FRIDAY INTO EARLY SATURDAY...WITH AN 
ASSOCIATED COLD FRONT. COULD SEE SOME LIGHT SNOW WITH THIS 
SYSTEM...BUT SOME MODELS KEEPING IT FURTHER WEST/SOUTH SO KEPT POPS 
LOW. STRONGER TROUGHING EXPECTED TO DIG INTO THE CENTRAL US 
SUNDAY...WITH ANOTHER CHANCE FOR SOME LIGHT SNOW...WITH COLDER AIR 
CONTINUING TO PUSH SOUTHWARD FROM CANADA AS H85 TEMPS FALL TO AROUND 
-8C TO -10C SUNDAY. BROAD TROUGHING ACROSS THE NORTHERN US INTO 
EARLY NEXT WEEK WILL LEAD TO COLDER AIR SEEPING SOUTHWARD WITH H85 
TEMPS DROPPING INTO THE TEENS BELOW CELSIUS ACROSS THE AREA MONDAY 
AND TUESDAY. THEREFORE AFTER A BRIEF WARMUP THROUGH MID 
WEEK...TEMPERATURES LOOK TO DROP TO BELOW AVERAGE VALUES BY LATE 
THIS WEEK INTO EARLY NEXT WEEK. 

&&

.AVIATION...
16/00Z...VFR CONDITIONS WILL PERSIST THROUGHOUT THE ENTIRE TAF 
FORECAST PERIOD WITH HIGH PRESSURE IN CONTROL OF THE WEATHER 
PATTERN.  SURFACE HIGH PRESSURE IS EXPECTED TO SHIFT EAST OVERNIGHT 
TONIGHT AND WEAK SOUTHERLY FLOW WILL DEVELOP PAST 09Z WED.  HIGH 
CIRRUS WILL INCREASE LATE IN THE TAF PERIOD WITH AN INCREASE IN 
MOISTURE AOA 20KFT.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...COGIL
AVIATION...PODRAZIK
LONG TERM...BEERENDS