Heavy Snow Warning 2, NWS Elko, NV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ELKO NV
246 AM PST THU DEC 6 2007

.SYNOPSIS...TEMPERATURES WILL BEGIN TO COOL LATE TODAY AS CLOUDS
THICKEN IN ADVANCE OF A STRONG LOW PRESSURE SYSTEM MOVING IN FROM THE
PACIFIC NORTHWEST...BRINGING RAIN AND SNOW TO THE SILVER STATE. THIS
SYSTEM HAS THE POTENTIAL TO SPREAD SIGNIFICANT SNOWFALL ACROSS
CENTRAL NEVADA THURSDAY NIGHT AND FRIDAY. &&

.SHORT TERM...TODAY THROUGH SATURDAY. IR AND WATER VAPOR IMAGERY
SHOWS DIRTY FLOW ALOFT OVER CREST OF DE-AMPLIFYING RIDGE THIS
MORNING. MID-HI CLOUDS MOVING ACROSS NORTHERN NEVADA ATTM. SHORT
TERM MODELS IN VERY GOOD AGREEMENT WITH THE DEVELOPING TROUGH.
UPPER LOW BEGINNING TO DESCEND DOWN THE CANADIAN COAST OFFSHORE.
THIS WILL BE THE IMPETUS FOR OUR WARNINGS AND ADVISORIES. MODELS
HAVE BEEN PROPOSING SIMILAR SOLUTIONS FOR A FEW DAYS NOW. WINTER
WEATHER WATCH WILL BE UPGRADED. THIS STRONG COLD UPPER LOW WILL
DIG SOUTH TODAY AND THE POS TILT AXIS OF TROUGH SHOULD BE OVER
NORTHERN CA BY THIS EVENING. EXPECT SHOWERS TO DEVELOP IN HUMBOLDT
COUNTY LATE THIS AFTERNOON...SPREADING ACROSS THE ENTIRE CWFA BY
MIDNIGHT. FOR WHITE PINE AND NORTHERN NYE COUNTIES...BEST QPF AMOUNTS
ARE DEPICTED BY GFS AND SREF ALLUDING TO 4 TO 8 INCHES OF SNOW
POSSIBLE FOR THE VALLEYS AND 8 TO 14 INCHES MOUNTAINS. REST OF
CWFA SHOULD BE IN THE 2 TO 5 INCHES RANGE FOR THE VALLEYS. SNOW
SHOULD DECREASE FRIDAY AFTERNOON FOR THE NORTH...HOWEVER WRAP AROUND
MOISTURE WILL PRODUCE SNOW SHOWERS...LOCALLY HEAVY AT TIMES...OVER SE
CWA THROUGH SATURDAY. LW

.LONG  TERM...SATURDAY NIGHT THROUGH WEDNESDAY...A STRONG LOW WILL
CONTINUE TO DIG A LITTLE FURTHER SOUTHWARDS THROUGH THE REST OF THE
WEEKEND. THIS WILL CONTINUE TO ALLOW COLD AIR TO REMAIN OVER THE
GREAT BASIN. HIGHS WILL BE GENERALLY IN THE 30S...WITH COLDER
TEMPS IN THE NORTH. WITH AN EXPECTED SNOW COVER DUE TO THE STORM
DUE BY THE WEEKEND...LOWS WILL DIP INTO THE SINGLE DIGITS. IF
CLOUDS CLEAR...WHICH IS VERY POSSIBLE...LOWS COULD GO NEGATIVE
SUNDAY AND MONDAY MORNINGS. GFS AND DGEX SHOWING 700MB TEMPS OF
AROUND -14C.

BY MONDAY AFTERNOON THE SYSTEM BEGINS TO EJECT RAPIDLY. AS IT DOES
A HIGHLY AMPLIFIED RIDGE IS PROGGED TO SLIDE EASTWARD PLACING A
MORE MODERATED NORTHERLY FLOW OVER THE SILVER STATE WITH THE
COLDEST AIR EAST OF THE CWA. THIS WILL HELP TO SLOWLY WARM TEMPS
CLOSER TO NORMAL FOR THE MIDDLE OF THE WEEK. IPPI
&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE DAY
EVEN THOUGH CEILING WILL BE GRADUALLY DROPPING AHEAD OF A LOW
PRESSURE SYSTEM MOVING INTO THE AREA. AS THIS SYSTEM MOVES IN...FROM
THE NORTHWEST...CEILINGS WILL BEGIN TO DROP TO IFR CONDITIONS BY THE
EVENING HOURS. ALSO EXPECTING SOME LIGHT PRECIPITATION TO ACCOMPANY
THESE LOWER CEILINGS. AT FIRST THE PRECIPITATION WILL BE RAIN...THEN
CHANGE OVER TO SNOW THIS EVENING. WITH THE CHANGE OVER TO SNOW...
VISIBILITIES WILL ALSO BEGIN TO DIMINISH RAPIDLY. WITH SOME OF THE
HEAVIER SNOW SHOWERS EXPECTED TONIGHT...VISIBILITIES COULD DROP
BELOW 1/2 SM. WINDS ARE NOT EXPECTED TO BE OF CONCERN FOR THIS
EVENT. THESE CONDITIONS WILL PERSIST THROUGH SATURDAY. &&

.LKN WATCHES/WARNINGS/ADVISORIES...WINTER STORM WATCH CONTINUES FOR
TODAY FOR HUMBOLDT...NORTHERN LANDER AND EUREKA...AND EXTREME EASTERN
ELKO COUNTIES.

A HEAVY SNOW WARNING IS IN AFFECT FOR THE RUBY MOUNTAINS...EASTERN
HUMBOLDT RANGE...AND FOR NORTHERN NYE COUNTY.

A SNOW ADVISORY IS IN AFFECT FOR NORTHERN AND CENTRAL ELKO...
SOUTHERN LANDER AND EUREKA...AND WHITE PINE COUNTIES.