FXUS65 KGJT 281014
AFDGJT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
314 AM MST SAT NOV 28 2009
.SHORT TERM DISCUSSION...TODAY THROUGH SUNDAY NIGHT...
MODELS STILL HAVING PROBLEMS RESOLVING HOW MUCH PCPN WILL MAKE IT
INTO OUR CWA AS QPF APPEARS THEN DISAPPEARS...THEN REAPPEARS. NAM
APPEARS TO BE LIGHTER WITH QPF ON THE 00Z RUN...BUT ITS BEEN THE
ODD MAN OUT. WILL FOLLOW THE GFS/EC/SREF WHICH HAVE BEEN A LITTLE
MORE CONSISTENT.
AS SUCH UPPER CLOSED LOW WILL DRIFT TO NEAR THE WRN AZ BORDER BY
THIS EVENING WHILE NRN BRANCH TROF MOVES INTO WY. THIS PUTS OUR CWA
UNDER A WELL DEFINED DEFORMATION ZONE. NOT A LOT OF BAROCLINICITY
SEEN WITH THIS STORM BUT A NICE COUPLET OF LOW LEVEL CONVERGENCE AND
UPPER LEVEL DIVERGENCE SEEN NEAR THE 4 CORNERS AS A RESULT OF
COUPLED JET STRUCTURE. ALTHOUGH TEMPS ALOFT NOT VERY EFFICIENT IN
TERMS OF CRYSTAL GROWTH WITH -15 C ISOTHERM WAY ABOVE MTN TOPS. BUT
BOTTOM LINE IS STILL EXPECT 5-10 INCHES OF SNOW OVER THE SAN JUANS...
SO WILL UPGRADE WATCH TO AN ADVISORY. FEEL SNOW ACCUMULATIONS IN THE
DURANGO AND PAGOSA SPRINGS AREAS WILL BE LIMITED BY MILD TEMPS AND
AS A RESULT EXPECT ONLY MINIMAL ACCUMULATIONS.
PCPN WILL TAPER OFF SUNDAY EVENING AND BE PRETTY MUCH OVER BY
MIDNIGHT AS LOW SINKS SOUTHWARD INTO MEXICO AND SUBSIDENCE TAKES
OVER.
.LONG TERM...MONDAY THROUGH THURSDAY MORNING...
UPPER LEVEL CUTOFF LOW CONTINUES SLOW EWRD MOVEMENT MONDAY AS OUR
SOUTHERN NEIGHBORS WILL RECEIVE MORE PRECIPITATION WHILE WEAK
RIDGING BUILDS IN OVER UT/CO. BY TUESDAY...NWLY FLOW WILL
SET UP OVER OUR AREA AS WEAK COLD FRONT PASSES WELL TO OUR N.
PREVIOUS MODEL RUNS BROUGHT THIS FRONT THRU OUR REGION CAUSING SOME
PRECIP...ESPECIALLY ALONG CONTINENTAL DIVIDE...BUT 00Z AND LATEST 06Z
GFS RUN HAS TAKEN ALL PRECIP OUT OF FORECAST AS UPPER LEVEL SUPPORT
PUSHES FURTHER N. LOWERED POPS/QPF FOR WED THRU THUR THOUGH SCHC
REMAINS IN FORECAST. IN CONTRAST...EUROPEAN 00Z RUN KEEPS PRECIP IN
FORECAST ALBEIT SOMEWHAT LOWER...WILL BE INTERESTING TO SEE HOW 12Z
MODEL RUN PLAYS OUT.
IN A NUTSHELL...BARRING ANY MAJOR MODEL FLUCTUATIONS...A MIX OF SUN
AND CLOUDS EXPECTED WITH TEMPS RUNNING ABOUT 3 TO 5 DEGREES ABOVE
NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...
VFR CONDITIONS EXPECTED AS HIGH CLOUDS STREAM OVER FORECAST AREA
TODAY. CONDITIONS WILL DETERIORATE FOR SRN AREAS AFTER 00Z THIS
EVENING...KMTR INCLUDED...AS UPPER LEVEL LOW APPROACHES FROM THE
WEST. SNOWFALL EXPECTED OVR SRN AREAS WITH CIG AND VIS DROPPING TO
IFR...POSSIBLY DROPPING TO LIFR...UNDER HEAVIER SNOWSHOWERS. NRN/CEN
MTN TOPS MIGHT BE OBSCURED AS CLOUDS LOWER AND SHOWERY TYPE PRECIP
OCCURS BUT TAF SITES...KEGE AND KASE...SHOULD REMAIN VFR.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT MST SUNDAY
NIGHT FOR COZ018-019.
UT...NONE.
&&
$$
SHORT TERM.....MC
LONG TERM......AS
AVIATION.......JAD
