FXUS65 KLKN 012214
AFDLKN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ELKO NV
214 PM PST TUE DEC 1 2009

.SYNOPSIS...DRY WEATHER WILL CONTINUE THROUGH AT LEAST FRIDAY.
SOME COLDER AIR WILL ENTER THE REGION BEGINNING WEDNESDAY...WITH
HIGH TEMPERATURES FALLING BELOW NORMAL ACROSS EASTERN NEVADA. A
MORE ACTIVE PATTERN LOOKS TO BE IN THE OFFING ACROSS THE REGION BY THIS
WEEKEND AND THE FIRST OF NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY. MODELS IN GOOD AGREEMENT
THROUGH THE SHORT TERM SHOWING A STRONG UPPER RIDGE ALONG THE WEST
COAST. A SHORT WAVE DIVING OVER THE RIDGE TONIGHT AND WEDNESDAY
WILL CARVE OUT A LARGE UPPER LOW OVER THE NATIONS MID SECTION.
COLDER AIR ON THE WRN EDGE OF THIS UPPER LOW WILL BRING COLDER
TEMPS TO NRN AND CNTRL NV. HIGHS ACROSS THE EAST WILL MOSTLY BE IN
THE 30S WHILE SOUTH CNTRL AND WRN NV WILL GENERALLY IN THE 40S. AS
THE COLD AIR PUSHES OFF TO THE EAST ON FRIDAY TEMPS WILL WARM
ABOUT 5 DEGREES. THE AIR MASS WILL REMAIN VERY DRY SO POPS WILL BE
AROUND ZERO. 

.LONG TERM...FRIDAY NIGHT THROUGH NEXT TUESDAY. BIG CHANGES COMING 
IN THE EXTENDED PERIOD WITH A LARGE PATTERN SWITCH...TURNING THE WX 
FROM DRY AND COOL TO MOIST AND COLD BY THE WEEKEND THROUGH THE 
BEGINNING OF NEXT WEEK. WEATHER PATTERN WILL BE DOMINATED BY A LARGE 
CUT-OFF POLAR VORTEX OVER THE PACIFIC NORTHWEST...ROTATING 
SHORTWAVES ACROSS THE GREAT BASIN REGION EVERY 12 TO 18HRS...BEFORE 
TRANSITIONING EASTWARD BY TUESDAY AFTERNOON. CONFIDENCE IS HIGH THAT 
BELOW AVG TEMPS WILL OCCUR WITH THE ARCTIC OSCILLATION INDEX
VALUES BECOMING STRONGLY NEGATIVE AND GEFS/ECWMF ENSEMBLE
SUPPORT.

BY SATURDAY A COLD FRONT WILL APPROACH NORTHERN NV...AND SLOWLY SAG 
SOUTH THROUGH THE CWA DURING THE DAY. TEMPERATURES WILL BE MUCH 
COLDER BEHIND THIS FRONT AS POLAR AIR MOVES INTO THE REGION WITH 
700H TEMPS DROPPING TO -14C. HIGHS WILL STRUGGLE TO REACH 40 ON 
SATURDAY ACROSS THE NORTH. COLDER AIR AND LOW LEVEL MOISTURE WILL 
MOVE INTO THE REGION WITH SCATTERED SNOW SHOWERS EXPECTED...MOSTLY 
ACROSS THE HIGHER TERRAIN. EVEN COLDER ON SUNDAY WITH HIGHS STUCK IN 
THE 30S ACROSS THE LOWER VALLEYS AND IN THE 20S ACROSS THE HIGHER 
TERRAIN. SCATTERED SNOW SHOWERS WILL CONTINUE ON SUNDAY...WITH UPPER 
LEVEL LOW ROTATING OVER HEAD AND LOW LEVEL MOISTURE IN PLACE. MODELS 
DIVERGE BY MONDAY WITH THE DETERMINISTIC GFS NOT PICKING UP ON 
SUB-TROPICAL MOISTURE AND ASSOCIATED SHORTWAVE ROTATING AROUND THE 
BASE OF THE UPPER LEVEL TROUGH...BUT THE 12Z GEFS AND ECMWF HAVE 
THIS FEATURE. HAVE KEPT CHANCE POPS THROUGH TUESDAY MORNING BASED ON 
THIS POSSIBLE INFLUX OF MOISTURE AROUND THE BASE OF THE TROUGH. IF 
MODELS CONTINUE TO HINT AT THIS FEATURE...WILL CONTINUE TO TREND 
POPS UP...ESPECIALLY ACROSS CENTRAL NV WHICH WILL BE CLOSER TO THE 
DEEP MOISTURE.  STILL A LOT OF UNCERTAINTY IN DETAILS AT THIS 
TIME...BUT THE CHANCE OF SNOW WILL CONTINUE THROUGH TUESDAY 
MORNING...BEFORE A SHORTWAVE RIDGE IS PROGGED TO MOVE INTO THE 
REGION BY MID-WEEK. STAYED TUNED AS THIS PATTERN EVOLVES OVER THE 
NEXT FEW DAYS. 

&&

.AVIATION...HIGH PRESSURE WILL DOMINATE THE WEATHER OVER NEVADA AND 
VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS.  WINDS WILL 
BECOME NORTHERLY AS A DRY COLD FRONT MOVES THROUGH THE REGION 
TONIGHT.   
 
&&

.CLIMATE...2ND DRIEST NOVEMBER ON RECORD FOR ELKO...
ONLY .01 INCH OF PRECIPITATION FELL AT THE ELKO AIRPORT WHICH 
MAKES THIS NOVEMBER THE 2ND DRIEST ON RECORD. ONLY 5  
NOVEMBERS REPORTED NO MEASURABLE PRECIPITATION DATING BACK
121 YEARS. ALSO ONLY 0.1 INCH OF SNOW FELL WHICH MAKES THIS
MONTH THE 18TH LEAST SNOWIEST ON RECORD WITH 17 OTHER YEARS 
REPORTING NO MEASURABLE SNOWFALL. THE AVERAGE TEMPERATURE OF 34.6 
DEGREES WAS 0.1 DEGREE ABOVE NORMAL. NO DAILY RECORDS WERE BROKE 
DURING THE MONTH.

...DRIEST NOVEMBER ON RECORD FOR ELY...
ONLY A TRACE OF PRECIPITATION FELL DURING THE MONTH OF NOVEMBER
WHICH TIES WITH 4 OTHER NOVEMBERS THAT HAD NO MEASURABLE
PRECIPITATION.ONLY A TRACE OF SNOW FELL WHICH TIES WITH 9 OTHER 
NOVEMBERS THAT SAW NO MEASURABLE SNOWFALL. THE AVERAGE 
TEMPERATURE OF 33.6 DEGREES WAS 0.1 DEGREE ABOVE NORMAL.
NO DAILY RECORDS WERE BROKE DURING THE MONTH.

&&

.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

91/95/95