Heavy Snow in Colorado, March 8, 2002

SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO COLORADO
254 PM MST THU MAR 7 2002

SNOW AND WIND OVER THE CENTRAL AND SOUTHWESTERN MOUNTAINS TONIGHT AND
FRIDAY THE CONCERN.

CURRENTLY...WINDY AND MILD WX ACROSS MUCH OF THE CWFA TODAY...WITH A
FEW GUSTS OVER 50 MPH ON THE PLAINS. WATER VAPOR SATELLITE IMAGES
REVEAL STRONG SUBSIDENCE/DRYING BEHIND INITIAL S/W TROUGH ACROSS SERN
CO DRIVING WINDS TODAY. FARTHER WEST...STRONGER/COLDER TROUGH MOVING
TOWARD THE GREAT BASIN WITH ISOLATED TSRA FROM NWRN CO BACK INTO UT
INDICATIVE OF STEEPENING MID LEVEL LAPSE RATES.

TONIGHT...UPGRADED WINTER STORM WATCH TO A WARNING FOR THE SAN JUANS
AND SAWATCH RANGE AS STRONG INSTABILITY AND GOOD OROGRAPHICS SHOULD
MAKE UP FOR MARGINAL DYNAMICS AND FAST MOVEMENT OF THE UPPER SYSTEM.
WENT WITH A SNOW/BLOWING SNOW ADVISORY FOR THE LA GARITAS/KLXV AS
THESE LOCATIONS ARE FAIRLY SHELTERED IN W-SW FLOW. MOST ACCUMS
SHOULD STAY FAIRLY HIGH IN ELEVATION...SHELTERED LOWER VALLEYS
LIKELY TO SEE MUCH LESS...THOUGH A FEW CONVECTIVE BURSTS ARE
POSSIBLE. SLIGHT CHCS FOR SNOW SHOWERS REMAINING MTNS AND WRN
VALLEYS SHOULD SUFFICE. WOULD EXPECT WINDS TO SLACKEN SOMEWHAT
OVERNIGHT AS DEEP MIXING ENDS...THOUGH STILL LOOKING FOR SPEEDS IN
THE 15 TO 30 MPH RANGE OVER LOWER ELEVATIONS.

FRIDAY...HIGHLIGHTS OUT WEST STILL WARRANTED AS SWRLY UPPER FLOW THE
FIRST HALF OF THE DAY BECOMES MORE WRLY BY AFTERNOON...SHIFTING THE
HEAVIEST SNOW FROM THE SAN JUANS NORTHWARD TOWARD THE SAWATCH RANGE.
AGAIN...JUST SLIGHT CHANCE TO CHANCE POPS REMAINING MTNS AND WRN
VALLEYS. SFC LOW SPINNING UP OVER THE ERN PLAINS SHOULD DRIVE FRONT
TO THE ARKANSAS RIVER BY MIDDAY THEN TOWARD THE NM BORDER BY SUNSET.
ETA HAS BACKED OFF ON WINDS AND PRECIP BEHIND THE FRONT...WHILE AVN
AT LEAST PLAYS UP THE WINDS A LITTLE MORE. WOULD EXPECT AT LEAST A
BRIEF PERIOD OF GUSTY NORTH WINDS BEHIND THE FRONT AS IT MOVES
ACROSS. PRECIP CHANCES LOOK PRETTY SMALL AS LOW LEVEL FLOW NEVER
GOES UPSLOPE...BUT WILL HOLD ON TO LOW POPS DUE TO COLD AIR ALOFT
AND INSTABILITY. GUIDANCE MAXES ALL OVER THE PLACE...GENERALLY
SIDED TO WHATEVER NUMBER WAS WARMER.

FRIDAY NIGHT...MAYBE SOME LINGERING -SHSN IN THE EVENING...BUT
STRONG SUBSIDENCE AND DRYING TAKE OVER BY MIDNIGHT. STILL SOME GUSTY
NORTH WINDS UNTIL 06Z OR SO...BUT APPEARS THEY WILL DIMMINISH
QUICKLY AFTERWARD...ALLOWING LOW TEMPS TO DROP BELOW 20 MOST
LOCATIONS.

SATURDAY...REMOVED MENTION OF WINDY ON THE PLAINS AS SFC GRADIENT IS
FAIRLY WEAK...STILL SHOULD HAVE SOME BREEZES MTN AREAS AS
UPPER RIDGING IS RATHER FLAT. BUMPED UP MAX TEMPS MOST AREAS AS
LATEST MODEL RUNS ARE NOT AS AGRESSIVE WITH CAA.

SUNDAY...LOOKS WARM WITH NICE DOWNSLOPE FLOW...ONLY PROBLEM MIGHT BE
SOME AFTERNOON WINDS AS LEE TROUGH DEEPENS AND UPPER FLOW BECOMES
MORE SWRLY AHEAD OF NEXT SYSTEM.

MONDAY...NEXT SYSTEM NOW LOOKS A DAY FASTER VS MODEL RUNS 24 HRS
AGO. THIS SEEMS REASONABLE AS UPPER PATTERN TRANSITIONS TO FAST W-
NW FLOW. AS A RESULT...MOVED SLIGHT -SHSN CHANCES FROM TUES TO MON
FOR THE CENTRAL AND SW MTNS...BUT KEPT THE REMAINING MTNS DRY.
ADDED WINDY AT TIMES TO MOST ZONES THROUGH THURSDAY AS UPPER JET
IS OVER OR JUST NORTH OF THE AREA...IT IS MARCH AFTER ALL.

PUB...WINTER STORM WARNING TONIGHT AND FRIDAY...SAWATCH RANGE/EASTERN
          SAN JUAN MTNS...ZONES 59/61.
      SNOW AND BLOWING SNOW ADVISORY TONIGHT AND FRIDAY...LA GARITA
          MOUNTAINS/LEADVILLE AND VICINITY...ZONES 58/60.

PETERSEN