PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
418 AM EDT TUE MAY 13 2008
 
VALID 12Z TUE MAY 13 2008 - 12Z FRI MAY 16 2008
 
DAYS 1 TO 3...

...CNTRL ROCKIES...

A VERY FORMIDABLE MID/UPPER LEVEL LOW... OVER WRN AZ/UT EARLY THIS
MORNING... WILL DIG SOUTH AND EAST THROUGH AZ INTO SRN NM OVER THE
NEXT 24 HRS. THIS SRN STREAM FEATURE SHOULD PINPOINT ENOUGH
VERTICAL LIFT AHEAD OF THE UPPER TROUGH AXIS AND IN VICINITY OF
THE LEFT EXIT REGION OVER CO TO TEAM WITH UPSLOPE OROGRAPHIC FLOW
AT THE SURFACE BEHIND A PLUNGING NRN STREAM COLD FRONT. THE
RESULTANT SHOULD BE HVY SNOW ACROSS THE CO ROCKIES EARLY IN TUES
BEFORE DISSIPATING BY WED MORNING. ON WED... THE BECOMING DOMINANT
UPPER RIDGE ALONG THE WEST COAST AND MORE UPSTREAM UPPER DYNAMICS
DIVING DOWN THE FRONT RANGE OF THE ROCKIES SHOULD KICK-OUT THE
POTENT CLOSED LOW INTO THE CENTRAL/SRN PLAINS. THIS WILL YIELD
LIKELY MARGINAL SNOWFALL POTENTIAL FROM ABSAROKA RANGE OF WY INTO
THE CO ROCKIES. BY THURS THEN... THE UPSTREAM DYNAMICS WILL DIG
AND BEGIN TO CLOSE OFF OVER NM/AZ INTO NRN MEXICO. THIS WILL BRING
ANOTHER POSSIBLE ROUND OF HVY SNOW ACROSS THE SRN CO
ROCKIES/SANGRE DE CRISTO RANGES. HPC BASICALLY FOLLOWED A BLEND OF
THE 12Z/12 ECMWF... 00Z GFS AND 21Z/12 SREF MEAN ON EACH FEATURE
ALL THREE DAYS. 

THE PROBABILITY OF SIGNIFICANT ICING IS LESS THAN 10 PERCENT.

MUSHER