FXUS66 KSTO 061757
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
1050 AM PDT MON OCT 6 2008
.DISCUSSION...
UPPER LEVEL RIDGE IS GRADUALLY AMPLIFYING AS AN UPPER TROF ALONG
140W MOVES TOWARDS THE PAC NW COAST. LOCAL AREAS OF STRATUS/FOG IN
THE MTN VALLEYS AROUND BURNEY BASIN...CHESTER...QUINCY...AND LAKE
CO...GRADUALLY ERODING AND SHOULD CONTINUE TO BE MIXED OUT AS DRIER
AIR ALOFT MIXES DOWN DUE TO INCREASING SUBSIDENCE TODAY. A LOOK AT
MORNING RAOBS SUGGESTS MAX TEMPS TODAY WILL BE 5 TO 11 DEG WARMER
OVER MOST LOCALES THAN ON SUN.
A STRONG 145 KT IS FORECAST TO BE ASSOCIATED WITH THE AFORE-
MENTIONED TROF...AND IS FORECAST TO RACE INTO THE PAC NW LATER
TODAY...AND EWD ACROSS THE NRN PLAINS STATES AND INTO THE NRN GREAT
LAKES REGION THROUGH THE WORK WEEK. THIS WILL FLATTEN THE RIDGE...
BUT WITH THE JET DYNAMICS PASSING WELL N OF NORCAL...THE COLD FRONT
ASSOCIATED WITH THE TROF WILL WEAKEN AS IT MOVES INTO THE NRN CA
COAST TONITE AND TUE MORNING. WE MAY SEE THE TAIL END OF THE
WEAKENING FRONTAL BAND CLOUDS BRUSH ACROSS OUR NRN ZONES.
OTHERWISE...NORCAL WILL BE ENJOYING SUNNY...WARM DAYS AND
COMFORTABLE/COOL NITES AS STRONG WLY FLOW RESULTS IN COMPRESSIONAL/
ADIABATIC WARMING INTO MID WEEK. THIS PATTERN WILL RESULT IN ABOVE
NORMAL MAX TEMPS UNTIL THE END OF THE WORK WEEK. THERE IS ONLY SOME
MINOR COOLING EXPECTED AROUND MID WEEK AS THE JET RACES EWD AND
WEAKENS OVER THE ERN PAC ALLOWING HEIGHTS TO BUILD. THIS RESULTS IN
THE BEGINNING OF A MAJOR PATTERN CHANGE WITH THE MEDIUM RANGE MODELS
DEVELOPING A DEEP CLOSED LOW...SOMEWHERE OVER THE GREAT BASIN. THE
DETAILS SHOW A WIDE RANGE OF SOLUTIONS OR POSSIBILITIES AT THIS
POINT...BUT ONE THING IS CERTAIN...IT WILL BE TURNING COOLER AND
WINDIER OVER NORCAL BY THE WEEKEND.
CONCERNS FOR THE MID WEEK PERIOD DEAL WITH BREEZY TO LOCALLY WINDY
POST-FRONTAL CONDITIONS WED/THU. SURFACE HIGH PRESSURE BUILDING
ACROSS THE PAC NW IS FORECAST TO INCREASE NLY GRADIENTS TO 9 TO 10
MBS ON WED...AND AROUND 14 MBS THU MORNING. THE TIGHTEST GRADIENTS
ARE FORECAST OVER OUR NRN ZONES DUE TO THE PACKING OF ISOBARS
BETWEEN MFR-CIC. GIVEN 925 MBS NAM WIND FORECAST WED NITE AND THU OF
NLY WINDS INCREASING TO AROUND 40 KTS AND THE FORECAST ISOBARIC
PATTERN...INTERIOR NORCAL COULD SEE THE DEVELOPMENT OF A NLY BARRIER
JET. THIS WILL BE SOMETHING THAT WE WILL BE MONITORING FOR WIND
ADVSRYS OR RED FLAGS...FOR PORTIONS OF THE AREA...IN LATER
FORECASTS. JHM
&&
.AVIATION...
HI PRES SLOLY WKNS OVR NORCAL AS PAC CDFNT APCHS W CST. VFR CONDS
OVR INTR NORCAL NXT 24 HRS EXC LCL IFR CONDS WITH TRRN OBSCD IN MTN
VLYS FM FOG AND ST TIL 19Z AND AGN AFT 06Z-19Z TUE.
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
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