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weather: incoming
By ccrossen | September 28, 2009
Get the warm weather while you can. We’re due for an abrupt end to Indian summer beginning Tuesday afternoon and evening, followed by very cold temps through Thrs. Brief respite, then another system comes in for the weekend.
From Reno NWS:
638 AM PDT MON SEP 28 2009
FOR TUESDAY…FRONT IS COMING IN SLOWER AND MAY NOT PASS I-80 UNTIL AROUND NOON AND SOUTHERN ZONES UNTIL 5-6 PM. IN ADDITION…SOME DOWNSLOPE SIGNATURES SHOWING UP IN MODELS ALONG SIERRA FRONT/MONO COUNTY 2-3 HRS PRIOR TO FRONTAL PASSAGE…. WIND GUSTS TO 45 MPH IF NOT STRONGER AND SUSTAINED WINDS AROUND 25 MPH.
SHORT TERM…
THE CHANGE TO A MUCH COOLER AND WINDY WEATHER PATTERN IS STILL SET TO OCCUR DURING THE NEXT COUPLE OF DAYS AS THE RIDGE THAT BROUGHT A FEW DAYS OF RECORD HIGH TEMPS WILL FINALLY YIELD TO AN UNSEASONABLY STRONG TROF APPROACHING THE WEST COAST. THE MAIN EFFECT TODAY WILL BE AN INCREASE IN SOUTHWEST WINDS. WHILE TEMPS WILL BEGIN TO DROP IN HIGHER ELEVATIONS BY THIS AFTERNOON…MOST VALLEYS WILL REMAIN QUITE WARM WITH HIGHS RANGING FROM THE MID 80S TO LOWER 90S AS FULL MIXING OCCURS WITH THE INCREASED WINDS. WINDS WILL REMAIN LOCALLY GUSTY THRU THE OVERNIGHT HOURS ESPECIALLY IN HIGHER ELEVATIONS. AS A RESULT…THE LAKE WIND ADVY WHICH IS BEING ISSUED FOR TAHOE STARTING THIS AFTERNOON WILL BE CARRIED THRU THE OVERNIGHT HOURS.
THE TROF IS EXPECTED TO MOVE ONSHORE BY TUES MORNING WITH COLD FRONT PUSHING ACROSS ERN CA AND WRN NV DURING THE DAY. THE STRONGEST WINDS WILL OCCUR AHEAD OF THE FRONT PASSAGE WITH GUSTS
OF 45 MPH OR HIGHER POSSIBLE ACROSS MUCH OF THE REGION. WHILE STRONG FRONTOGENESIS ALOFT COULD TRIGGER SOME SHOWERS IN PORTIONS OF NERN CA-NWRN NV BY TUES AFTN AND INTO PARTS OF W-CNTRL NV TUES EVE…THE POTENTIAL FOR MEASURABLE RAINFALL WILL BE RATHER LOW DUE TO THE EXPECTED FAST CELL MOVEMENT AND QUICK DEPARTURE OF THIS FORCING TO CNTRL-ERN NV BY EARLY TUES EVE. THE COOLING EFFECTS OF THE FRONT WILL DEFINITELY BE NOTICED WITH MANY AREAS 15-25 DEGREES COLDER THAN TODAY…
BY WEDNESDAY…A FEW VERY LIGHT SHOWERS MAY AFFECT ERN PERSHING-CHURCHILL COUNTIES IN THE MORNING UNDER THE MID LEVEL CYCLONIC FLOW…OTHERWISE DRY CONDITIONS WILL PREVAIL ACROSS THE REGION WITH MAX TEMPS EVEN COOLER THAN TUESDAY AS WINDS SHIFT TO THE NORTHWEST AND NORTH. SOME VALLEY SITES MAY FAIL TO REACH 60 DEGREES ESPECIALLY IF ENOUGH STRATOCUMULUS PERSISTS INTO THE AFTERNOON. WHILE WINDS WILL NOT BE NEARLY AS STRONG COMPARED TO TUESDAY…GUSTS BETWEEN 20 AND 30 MPH WILL GIVE THE REGION CHILLY FALL CONDITIONS MORE COMMON FOR LATE OCTOBER OR EARLY NOVEMBER.
THE POTENTIAL FOR FREEZING TEMPS WILL INCREASE WED NIGHT AS SKIES CLEAR AND WINDS DECOUPLE IN MOST VALLEYS. HARD FREEZE CONDITIONS COULD OCCUR IN MANY LOCATIONS AWAY FROM URBAN AREAS.
LONG TERM…THURSDAY THROUGH SUNDAY…
SIERRA SHOULD SEE A BIT MORE OF A WARMUP DUE TO HIGHER ELEVATIONS BETTER ABLE TO MIX INTO INVERSION. FRI…FLOW BEGINS TO SWITCH TO WEST AHEAD OF APPROACHING TROF FROM THE NORTH ALLOWING FOR A BIT MORE WARMING. TEMPS LOOK TO PEAK IN MID 70S WRN NV TO JUST SHORT OF 70 IN SIERRA VALLEYS…CLOSE TO NORMAL.
COLD FRONT EXPECTED TO MOVE SOUTH OF THE OREGON BORDER SAT AFTERNOON AND PUSH SLOWLY SOUTHWARD AND THROUGH THE AREA INTO SUNDAY AFTERNOON. WITH A SLIGHTLY FURTHER WEST TRAJECTORY AND SLOWER MOVEMENT…THIS TROUGH LOOKS A BIT WETTER THAN TUE/TUE NIGHTS. HOWEVER…ALL PRECIP LOOKS TO BE POST-FRONTAL TYPICAL OF EARLY AUTUMN SYSTEMS. WINDS WILL BE A BIT BREEZY SAT AHEAD OF THE FRONT BUT NOT AS STRONG AS TODAY/TUE WITH PK GUSTS TO 35 MPH OR SO.
AS FRONT PUSHES SOUTH…EXPECT A DECENT BAND OF PRECIP TO DEVELOP JUST BEHIND IT NORTH OF SUSANVILLE-GERLACH SO HAVE CONTINUE WITH HIGHER CHC POPS THERE AND SLIGHT CHC FURTHER SOUTH. FGEN DOES NOT LOOK AS STG AS THE FRONT DROPS FURTHER SOUTH INTO SUN ALTHOUGH THIS IS STILL UP IN THE AIR. OVERALL HIGH CONFIDENCE IN THE PATTERN ITSELF WITH MILD WEATHER LATE WEEK TURNING MUCH BELOW NORMAL AGAIN FOR THE WEEKEND. STILL CONSIDERABLE UNCERTAINTY THOUGH WITH AMOUNT/LOCATION AND COVERAGE OF PRECIP FOR THE WKEND. WALLMANN
Topics: Tahoe Snow Report |