868 FXUS65 KVEF 281534 AFDVEF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 830 AM PDT FRI MAR 28 2014 .SYNOPSIS...DRY CONDITIONS AND WARMING TEMPERATURES CAN BE EXPECTED TODAY THROUGH SATURDAY AHEAD OF A STORM SYSTEM WHICH WILL MOVE THROUGH THE AREA SATURDAY NIGHT INTO SUNDAY. THIS SYSTEM WILL BRING WITH IT INCREASING CLOUDS...WIND...AND CHANCES FOR PRECIPITATION IN THE SIERRA AND NORTHERN PORTIONS OF THE FORECAST AREA. ANOTHER STORM SYSTEM IS FORECAST TO MOVE IN EARLY NEXT WEEK. && .UPDATE...FORECAST LOOKS IN GOOD SHAPE. JUST SOME PASSING HIGH CLOUDS EXPECTED TODAY WITH OTHERWISE SUNNY SKIES. TEMPERATURES WILL RISE TO NEAR SEASONAL NORMALS TODAY. && .AVIATION...FOR MCCARRAN...VARIABLE WINDS TYPICALLY OUT OF THE SOUTH OR SOUTHWEST ARE EXPECTED TO PERSIST THROUGH 19Z BEFORE DEVELOPING AN EASTERLY COMPONENT LATE THIS MORNING OR EARLY AFTERNOON. SPEEDS SHOULD BE GENERALLY LESS THAN 7 KTS. TYPICAL DRAINAGE SOUTH/SOUTHWEST WINDS ARE EXPECTED AGAIN TONIGHT. SCT-BKN HIGH CLOUDS THROUGH THE PERIOD. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...LIGHT AND VARIABLE WINDS WINDS ACROSS MOST OF THE REGION THROUGH THIS MORNING GIVING WAY TO SOUTHWEST TO WEST WINDS OF 10-20 KTS THIS AFTERNOON AND EVENING. TYPICAL LIGHT DRAINAGE WINDS TONIGHT INTO EARLY SATURDAY MORNING. AREAS OF GUSTY SOUTHWEST WINDS WILL DEVELOP LATE SATURDAY. SCT-BKN HIGH CLOUDS THROUGH SATURDAY MORNING. && .PREV DISCUSSION...305 AM PDT .SHORT TERM...MODELS ARE IN GOOD AGREEMENT WITH THE OVERALL PATTERN THROUGH SUNDAY NIGHT. A RIDGE OF HIGH PRESSURE WILL TRAVERSE THE AREA TODAY AND TONIGHT INTO SATURDAY. THIS WILL LEAD TO DRY CONDITIONS AND A WARMING TREND. HIGH TEMPERATURES WILL BE WELL ABOVE NORMAL SATURDAY. THE RIDGE AXIS WILL SHIFT EAST OF THE AREA SATURDAY AFTERNOON AS A SHORTWAVE TROUGH APPROACHES THE COAST. WINDS WILL PICK UP ACROSS THE AREA LATE SATURDAY BUT THE LATEST MODEL GUIDANCE INCLUDING THE HI-RES MODELS INDICATES WINDS REMAINING BELOW ADVISORY LEVELS FOR THE MOST PART. I STILL THINK THERE IS SOME POTENTIAL FOR SOME PRETTY STRONG SOUTHWEST WINDS IN THE SIERRA AND SPRING MOUNTAINS LATE SATURDAY AFTERNOON AND EVENING. THIS SHORTWAVE WILL MOVE ACROSS THE AREA SATURDAY NIGHT AND SUNDAY LEADING TO A CHANCE OF SHOWERS ACROSS THE NORTHERN PORTION OF THE FORECAST AREA...ESPECIALLY IN THE SIERRA SATURDAY NIGHT AND OVER LINCOLN COUNTY SUNDAY. THE HIGHER ELEVATIONS OF THE SIERRA MAY SEE A DECENT SHOT OF SNOWFALL BUT IMPACTS ARE EXPECTED TO BE LIMITED AT ELEVATIONS WITH ROADWAYS AND POPULATION. PORTIONS OF LINCOLN COUNTY COULD SEE AROUND TWO TENTHS OF AN INCH OF RAIN SUNDAY. LOCALLY BREEZY CONDITIONS ARE EXPECTED SUNDAY WITH WIND DIRECTION SHIFTING FROM SOUTHWEST TO WEST AND NORTHWEST. THIS SHORTWAVE WILL ALSO BRING SIGNIFICANT COOLING SUNDAY WITH TEMPERATURES GENERALLY DROPPING BACK TO BELOW NORMAL LEVELS. ZONAL FLOW WILL BRING DRY CONDITIONS SUNDAY NIGHT. .LONG TERM...MONDAY THROUGH FRIDAY NIGHT. ANOTHER SYSTEM IS STILL EXPECTED TO IMPACT THE AREA FROM MONDAY THROUGH WEDNESDAY MORNING. A LARGE MID/UPPER LEVEL TROUGH IS EXPECTED TO APPROACH FROM THE WEST ON MONDAY ACCOMPANIED BY A COLD AREA OF LOW PRESSURE. THE MAIN IMPACT FOR MONDAY AFTERNOON THROUGH MONDAY NIGHT CONTINUES TO LOOK LIKE GUSTY WINDS AS A 130 KT+ JET STREAK AT 250 MB ROUNDS THE BASE OF THE TROUGH. 700 MB WINDS OFF THE GFS AND ECMWF CONTINUE TO SHOW WIDESPREAD 30-40 KT+ VALUES ACROSS OUR AREA AND MODEL 500 MB HEIGHTS SHOW A HYDRAULIC JUMP SIGNATURE TO THE LEE OF THE SOUTHERN SIERRA. THIS SHOULD RESULT IN GUSTY GRADIENT SOUTHWEST TO WEST WINDS ACROSS THE AREA WITH THE POTENTIAL FOR DOWNSLOPE WINDS TO THE LEE OF THE SOUTHERN SIERRA, SPRING MOUNTAINS AND POTENTIALLY THE WHITE MOUNTAINS. WIND HEADLINES OF SOME SORT MAY EVENTUALLY BE NEEDED. WITH THE RECENT DRY CONDITIONS BLOWING DUST WILL BE A CONCERN. DESPITE AN IMPRESSIVE INFLUX OF MOISTURE, FAVORABLE LIFT FROM THE JET AND GOOD MID-LEVEL FORCING SHOULD BE ENOUGH TO SPREAD SOME SHOWERS ACROSS THE NORTHERN HALF OF THE AREA FROM MONDAY THROUGH WEDNESDAY MORNING. WITH THE COLD POOL ALOFT PASSING OVERHEAD, ENOUGH INSTABILITY MAY ALLOW FOR A FEW THUNDERSTORMS AS WELL MAINLY ON TUESDAY. 700 MB TEMPS AS LOW AS -8C ARE FORECAST, BUT MOST OF THE MOISTURE AND BEST FORCING SHOULD BE GONE BY THEN, SO SNOW LEVELS ARE ONLY FORECAST TO DROP TO 5000-5500 FEET ON AVERAGE WHEN PRECIP IS FORECAST. WHILE MONDAY SHOULD STILL SEE TEMPS NEAR NORMAL, HIGHS SHOULD BE ABOUT 6-10 DEGREES BELOW NORMAL FOR TUESDAY AND WEDNESDAY. THE ECMWF REMAINS THE COLDER MODEL AND WE KEPT A BLEND OF THIS WITH THE WARMER GFS FOR TEMPS. BEHIND THE DEPARTING COLD UPPER LOW THE FLOW ALOFT SHOULD TRANSITION TO THE WEST ALLOWING FOR SOME MODERATION OF TEMPS FOR THURSDAY PUSHING THEM CLOSER TO NORMAL. MODELS SHOW ANOTHER MID/UPPER LEVEL TROUGH ARRIVING FOR LATE NEXT WEEK BUT SHOW A BIG SPREAD IN THE TIMING WITH THE ECMWF FASTER AND THE GFS AND GEM SLOWER. FOR NOW, WE WENT WITH A BLEND OF THE TWO BUT LEANED TOWARD THE SLOWER SOLUTION. WE BROUGHT IN THE POTENTIAL FOR SHOWERS TO OUR NORTHERN CWFA MAINLY STARTING ON THURSDAY NIGHT. WINDS WITH THIS NEXT SYSTEM DO NOT APPEAR AS STRONG AT THIS TIME AS THE JET IS NOT PROGGED AS STRONG. && .VEF WATCHES/WARNINGS/ADVISORIES... NV...NONE. AZ...NONE. CA...NONE. && $$ HARRISON/STACHELSKI FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE: HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER