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000
FXUS65 KBOU 281022
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
322 AM MST THU NOV 28 2013

.SHORT TERM...WEAK COLD FRONT PUSHED THROUGH NORTHEAST COLORADO
YESTERDAY EVENING. THIS WILL BRING COOLER AIR INTO THE AREA TODAY.
HIGHS WILL BE ABOUT 15 DEGREES COOLER THAN YESTERDAY WHICH WILL PUT
THEM IN THE MID 40S TO LOWER 50S RANGE ACROSS NORTHEAST COLORADO. AT
THE UPPER LEVELS...A WEAK RIDGE OVER COLORADO WILL EXIT THE STATE BY
TONIGHT LEAVING A SOUTHWEST FLOW ALOFT ACROSS COLORADO. A VORT MAX
CURRENTLY OFF THE SOUTHERN CALIFORNIA COAST WILL MOVE ACROSS THE
DESERT SOUTHWEST TODAY AND INTO SOUTHERN COLORADO LATE TONIGHT. THIS
WILL ONLY LEAD TO AN INCREASE IN HIGH CLOUDS THIS AFTERNOON AND
TONIGHT. LOWS TONIGHT WILL BE NEAR TO SLIGHTLY ABOVE NORMAL WITH
MOST SPOTS ACROSS NORTHEAST COLORADO BOTTOMING OUT IN THE 20S.

.LONG TERM...WNW FLOW ALOFT WILL BE OVER THE AREA THRU SAT WITH ONLY
SOME MID AND HIGH LEVEL MOISTURE MOVING ACROSS. OUTSIDE OF SOME
HIGHER LEVEL CLOUDS WILL KEEP FCST DRY BOTH DAYS. AS FOR HIGHS
READINGS SHOULD BE IN THE LOWER TO MID 50S OVER NERN CO.

FOR SAT NIGHT INTO SUN THERE WILL BE SOME INCREASE IN MOISTURE OVER
THE MTNS IN WNW FLOW ALOFT AS A WK DISTURBANCE MOVES ACROSS.  THUS
MAY SEE A CHC OF OROGRAPHIC -SHSN.  OVER NERN CO IT WILL REMAIN DRY
WITH ONLY SOME MID AND HIGH LVL CLOUDS.  AS FOR HIGHS READINGS
SHOULD STAY SLIGHTLY ABOVE NORMAL WITH TEMPS IN THE LOWER TO MID
50S ACROSS THE PLAINS.

BY MON THE FLOW ALOFT WILL BECOME MORE WLY AS A STG UPPER LEVEL
TROUGH DEVELOPS OVER THE PACIFIC NORTHWEST.  CURRENT CROSS-SECTIONS
SHOW MOISTURE WILL BE MAINLY ABV 500 MB SO SNOW SHOWER THREAT IN THE
MTNS LOOKS RATHER LOW AT THIS TIME WITH DRY CONDITIONS OVER NERN CO.
HIGHS ON MON SHOULD CONTINUE ABV NORMAL OVER NERN CO WITH READINGS
IN THE 50S.

FOR TUE BOTH THE ECMWF AND GFS SHOW A STG UPPER LEVEL TROUGH OVER
THE WRN US WITH SWLY FLOW ACROSS NRN CO.  THERE COULD BE SOME
INCREASE IN MOISTURE ACROSS THE MTNS WITH THE BEST CHC OF SNOW NORTH
OF I-70. OVER NERN CO THERE ARE SOME DIFFERENCES BETWEEN THE ECMWF
AND GFS WITH RESPECT TO AN INITIAL COOL FRONT.  THE ECMWF MOVES THIS
FNT INTO NERN CO ON TUE WHILE THE GFS HOLDS IT OFF UNTIL TUE NIGHT.
AS A RESULT THE ECMWF KEEPS HIGHS IN THE 40S OVER NERN CO WHILE THE
GFS HAS TEMPS IN THE 50S.  FOR NOW WILL GO WITH A FASTER MOVEMENT
AND KEEPS HIGHS IN THE 40S.  AS FOR PCPN IT SHOULD REMAIN DRY OVER
NERN CO EXCEPT FOR A SLIGHT CHC OF SHOWERS NR THE WY BORDER BY TUE
AFTN.

BY WED THE ECMWF AND GFS HAVE SOME DIFFERENCES WITH RESPECT TO THE
UPPER LEVEL PTRN.  THE ECMWF HAS AN INTENSE UPPER LEVEL LOW OVER THE
WRN US WHILE THE GFS HAS AN ELONGATED UPPER LEVEL TROUGH EXTENDING
FM THE NRN ROCKIES INTO SRN CALIFORNIA.  HOWEVER BOTH SOLUTIONS
WOULD PRODUCE RATHER STG SWLY FLOW ALOFT OVER NRN CO AS SOME COLDER
AIR FILTERS INTO NERN CO BEHIND A COLD FNT.  AT THIS TIME CROSS-
SECTIONS SHOW RATHER LIMITED MOISTURE ACROSS MUCH OF THE AREA ON WED
SO WILL KEEP POPS ON THE LOW SIDE FOR NOW.  AS FOR HIGHS WILL DROP
READINGS INTO THE 30S ACROSS NERN CO.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE NEXT 24 HOURS
WITH HIGH CLOUDS INCREASING THROUGH THE DAY. FORECASTING WIND
DIRECTION WILL BE TRICKY BECAUSE OF A DENVER CYCLONE...HOWEVER
WIND SPEEDS SHOULD STAY BELOW 15 KNOTS. SOUTHERLY WINDS ARE
EXPECTED TO PERSIST THIS MORNING. WINDS MAY SHIFT NORTHERLY AFTER
18Z AS A DENVER CYCLONE STRENGTHENS...BUT THIS DEPENDS ON WHERE
THE CYCLONE FORMS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MEIER
LONG TERM....RPK
AVIATION...MEIER