Avalanche in Colorado, March 24, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
330 AM MST THU MAR 24 2005

.SHORT TERM...A HODGE PODGE OF WEATHER TO CONTEND WITH IN THE FIRST
TWO PERIODS.  THE FIRST ISSUE WILL BE THE FOG THIS MORNING.  WEAK
CYCLONE THIS MORNING HAS BROUGHT THE FOG AND STRATUS BACK INTO THE
URBAN CORRIDOR.  MOST DENSE FOG HAS BEEN EAST OF THE URBAN CORRIDOR
EARLY THIS MORNING...BUT AS A PRECAUTION I HAVE OPTED TO ISSUE A
DENSE FOG ADVISORY FOR THE NORTHEAST PLAINS THROUGH 9 AM MST THIS
MORNING.  THE FIRST SHORT WAVE TROF...OVER NRN UTAH AND SRN IDAHO IS
PROGGED TO PASS INTO THE NEBRASAKA PANHANDLE BY THIS AFTERNOON.
THERE IS SOME WEAK QG ASCENT ASSOCIATED WITH THIS SYSTEM...BUT MOST
OF THE ENERGY RMNS NORTH OF COLORADO.  SHALLOW UPSLOPE IS ALSO
PROGGED TO DEVELOP BY THIS AFTERNOON AND CONTINUE INTO TONIGHT.
MOST OF THE UPSLOPE IS FCST TO REMAIN BELOW 700 MB...BUT THERE IS
ENOUGH UPSLOPE AND MOISTURE...COUPLED WITH SOME INSTBY IN THE
AFTERNOON AND EVENING...TO UP POPS ALONG THE FRONT RANGE.  BEST
POTENTIAL FOR SNOWFALL WILL BE ALONG THE FRONT RANGE FOOTHILLS AND
PALMER DIVIDE.  LATER SHIFTS CAN ASSESS WHETHER AN ADVISORY IS
WARRANTED.  FOR NOW NOT IMPRESSED ENOUGH WITH THE UPSLOPE TO HOIST
SUCH A HIGHLIGHT AT THIS TIME.

.LONG TERM...MAIN CONCERN WILL BE THE DEVELOPMENT AND PASSAGE OF
NEXT MAJOR TROF ACROSS THE AREA ON FRI NITE AND SATURDAY. MODELS
BEGINNING TO DRAW A CONSENSUS ON THE EVOLUTION OF THE LOW WITH MAJOR
PLAYERS SHOWING A BROAD CUTOFF LOW ACROSS FAR NW NEW MEXICO ON 12Z
SAT. THE NAM WAS THE LAST PLAYER TO CONCUR...AS PREVIOUS RUNS HAS
BEEN SLOWER AND FURTHER NORTH WITH DEVELOPEMENT. LATEST 06Z NAM RUN
HAS NOW FALLEN IN LINE WITH GFS AND OTHER INTERNATIONAL PLAYERS.

AHEAD OF THE LOW ON FRIDAY...THERE WILL BE SOME BRIEF RIDGING ALOFT
EARLY IN THE DAY AHD OF THE LOW. APPEARS THERE WILL BE PLENTY OF LOW
LVL MSTR AND EXPECT WIDESPREAD STRATUS AND AREAS OF FOG FRI AM BLO
STRONG INVERSION NEAR 750 MB. FORECAST SOUNDINGS SHOW ENOUGH
INSTABILITY DEVELOPING LATER IN THE DAY ALONG WITH DECENT UPWARD
FORCING AHD OF THE TROF TO TRIGGER SHOWER ACTIVITY INCREASING BY
NIGHTFALL. WITH PLACEMENT OF THE LOW...APPEARS A DECENT WINDOW OF
PRECIP ACROSS THE CWA FOR LATE FRI NITE THRU AT LEAST MIDDAY
SATURDAY WITH LOW LVL WINDS SHIFTING BACK NORTHEAST AND STRONG QG
VERTICAL VELOCITY VALUES. THERE IS THE POTENTIAL FOR SIGNIFICANT
SNOWFALL...ESP ACROSS SRN/WRN SECTIONS OF CWA. SNOW SHOULD BE
WINDING DOWN SAT AFTN FROM NORTH TO SOUTH AS MAIN LOW RAPIDLY DROPS
SOUTHEAST INTO NORTH CENTRAL TEXAS BY 00Z SUN. THE PERIODS OF
CONCERN ARE STILL 4TH-5TH PRDS...SO NO WATCHES YET. MAIN CHANGES TO
ZONES WILL BE TO TREND POPS UPWARD TO HIGH SCATTERED AND DROP TEMPS
CONSIDERABLY ON SAT.

RIDGE ALOFT BUILDING BACK INTO THE REGION ON SUN-MON WITH A RETURN
TO DRIER AND WARMER CONDITIONS. BACKED OFF A BIT ON HIGH TEMPS ON
SUN...ESP IF THERE IS SNOW COVER IN SOME LOCALES. THE NEXT TROF WILL
BE MOVING ACROSS THE REGION LATE TUE-WED. THERE ARE SOME TIMING
DIFFERENCES SHOWING UP IN THE MODELS AND WOULD PERFER TO WAIT
ANOTHER DAY BEFORE MAKING ANY MAJOR CHANGES ON THOSE OUT PERIODS.

&&
.BOU WATCHES/WARNINGS/ADVISORIES...DENSE FOG ADVISORY FOR THE URBAN
CORRIDOR AND NORTHEAST PLAINS UNTIL 9 AM MST THIS MORNING...ZONES
38>51.

&&

COOPER/ENTREKIN

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE DENVER CO
1102 AM MST THU MAR 24 2005

COZ030>051-251300-
JACKSON COUNTY BELOW 9000 FEET-WEST JACKSON AND WEST GRAND
COUNTIES ABOVE 9000 FEET-GRAND AND SUMMIT COUNTIES BELOW 9000
FEET-SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/
NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET-SOUTH AND SOUTHEAST
GRAND/WEST CENTRAL AND SOUTHWEST BOULDER/GILPIN/CLEAR CREEK/
SUMMIT/NORTH AND WEST PARK COUNTIES ABOVE 9000 FEET-LARIMER AND
BOULDER COUNTIES BETWEEN 6000 AND 9000 FEET-JEFFERSON AND WEST
DOUGLAS COUNTIES ABOVE 6000 FEET/GILPIN/CLEAR CREEK/NORTHEAST PARK
COUNTIES BELOW 9000 FEET-CENTRAL AND SOUTHEAST PARK COUNTY-LARIMER
COUNTY BELOW 6000 FEET/NORTHWEST WELD COUNTY-BOULDER AND JEFFERSON
COUNTIES BELOW 6000 FEET/WEST BROOMFIELD COUNTY-NORTH DOUGLAS
COUNTY BELOW 6000 FEET/DENVER/WEST ADAMS AND ARAPAHOE COUNTIES/
EAST BROOMFIELD COUNTY-ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES
ABOVE 6000 FEET-NORTHEAST WELD COUNTY-CENTRAL AND SOUTH WELD
COUNTY-MORGAN COUNTY-CENTRAL AND EAST ADAMS AND ARAPAHOE COUNTIES-
NORTH AND NORTHEAST ELBERT COUNTY BELOW 6000 FEET/NORTH LINCOLN
COUNTY-SOUTHEAST ELBERT COUNTY BELOW 6000 FEET/SOUTH LINCOLN
COUNTY-LOGAN COUNTY-WASHINGTON COUNTY-SEDGWICK COUNTY-PHILLIPS
COUNTY-
1102 AM MST THU MAR 24 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL
COLORADO.

.DAY ONE...TODAY AND TONIGHT

SNOW SHOWERS WILL BECOME MORE WIDESPREAD IN THE MOUNTAINS AND
FOOTHILLS THIS AFTERNOON AND ALSO SPREAD ONTO THE PLAINS.  THE SNOW
WILL CONTINUE THROUGH MUCH OF THE EVENING BEFORE DIMINISHING LATE
TONIGHT.  ACCUMULATIONS OF 1 TO 3 INCHES CAN BE EXPECTED ALONG THE
I-25 CORRIDOR...WITH 3 TO 6 INCHES IN THE MOUNTAINS AND FOOTHILLS.
LITTLE IF ANY ACCUMULATION IS EXPECTED EAST OF A GREELEY TO LIMON
LINE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A STORM SYSTEM WILL MOVE INTO THE FOUR CORNERS AREA BY FRIDAY NIGHT
AND THEN MOVE SOUTHEAST INTO CENTRAL NEW MEXICO ON SATURDAY.  THIS
SYSTEM MAY INCREASE THE CHANCE OF SNOW IN THE MOUNTAINS AND IN AND
NEAR THE FOOTHILLS FRIDAY NIGHT INTO SATURDAY MORNING.  DRIER
WEATHER WILL MOVE INTO THE AREA ON SUNDAY AND MONDAY AS AN UPPER
LEVEL RIDGE BUILDS INTO THE AREA.  ANOTHER SYSTEM MAY AFFECT THE
AREA ON TUESDAY AND BRING A CHANCE OF SNOW MAINLY TO THE MOUNTAINS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.