000
FXUS65 KPSR 061252
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
550 AM MST MON FEB 6 2012

.UPDATE...UPDATED FIRE WEATHER DISCUSSION.

&&

.SYNOPSIS...
DRY CONDITIONS AND NEAR-NORMAL TEMPERATURES WILL CONTINUE THROUGH
TUESDAY. AN APPROACHING PACIFIC DISTURBANCE...MOVING TOWARD THE
SOUTHERN CALIFORNIA COAST TUESDAY...WILL BRING A SLIGHT CHANCE OF
SHOWERS TO THE REGION LATE TUESDAY NIGHT AND WEDNESDAY. THE BEST
SHOWER CHANCES STAY MAINLY ACROSS SOUTHERN CALIFORNIA...WITH
MOSTLY CLOUDY SKIES EXPECTED FOR THE ARIZONA DESERTS. DRY AND
WARMER WEATHER WILL RETURN TO THE REGION LATE THIS WEEK AND INTO THE
WEEKEND.

&&

.DISCUSSION...
TODAY THROUGH TUESDAY MIDDAY...
LARGE UPPER LEVEL LOW STILL ROTATING OVER THE CENTRAL ROCKIES/GREAT
BASIN STATES THIS MORNING AND IS SHOWING VERY SLOW MOVEMENT OF THE
CIRCULATION CENTER TO THE EAST. SOME LINGERING MID TO HIGH LEVEL
MOISTURE WILL PRODUCE SCATTERED HIGH CLOUDS TODAY AND INTO TUESDAY
FOR THE SOUTHWEST DESERTS. AS THE LOW FEATURE CONTINUES TO TRACK
EASTWARD...A WEAK UPPER LEVEL RIDGE WILL SETTLE ACROSS THE REGION
CONTINUING PERIODIC HIGH CLOUDINESS AND MILD TEMPERATURES.

TUESDAY AFTERNOON THROUGH THURSDAY...
MORE NOTICEABLE INCREASE TO THE CLOUDS WILL BEGIN TUESDAY AFTERNOON
AS THE NEXT SIGNIFICANT LOW PRESSURE SYSTEM DROPS ALONG THE
CALIFORNIA COAST. THIS SYSTEM LOOKS TO HIT MOST OF THE CALIFORNIA
COAST WITH DECENT PRECIPITATION AMOUNTS BEFORE THE BULK OF THE LOW/S
ENERGY CUTS OFF FROM THE UPPER LEVEL JET STREAM. GIVEN THE LATEST
FORECAST MODEL RUNS...BEST CHANCES FOR MEASURABLE PRECIPITATION LIE
ACROSS SOUTHEASTERN CALIFORNIA TUESDAY NIGHT INTO EARLY WEDNESDAY
MORNING. THERE MAY BE A FEW STRAY SHOWERS THAT WORK THEIR WAY INTO
THE SOUTHWEST CORNER OF ARIZONA...BUT CHANCES ARE NOT LOOKING GOOD
FOR RAINFALL FURTHER EAST INTO THE PHOENIX AREA.

MOSTLY CLOUDY SKIES AS WELL AS CONTINUED MILD TEMPERATURES EXPECTED
FOR MIDWEEK...ALTHOUGH LATEST MODEL TEMPERATURE GUIDANCE SHOWS
TEMPERATURES NOT COOLING TOO MUCH EVEN WITH THE ENHANCED CLOUD COVER.
NORTHERLY FLOW TAKES HOLD AS THE CUTOFF CONTINUES TO MOVE SOUTH DOWN
THE BAJA PENINSULA THURSDAY...CREATING PERIODS OF INCREASED WINDS
DOWN THE COLORADO RIVER VALLEY. THERE ARE STILL SLIGHT MODEL
DISCREPANCIES WITH THE PATTERN FOR THURSDAY AS THE GFS/NAM HAVE A
WEAK BUT ALSO DRY SHORTWAVE FEATURE BRUSHING THROUGH THE FOUR CORNERS
WHEREAS THE EUROPEAN/CANADIAN SOLUTIONS SHOWING A STRONGER AND MORE
MOIST WAVE FEATURE THAT COULD GENERATE SOME SHOWERS ACROSS EASTERN
PORTIONS OF THE STATE/THE HIGHER TERRAIN. PRECIP FORECASTS WERE
HEDGED TOWARD CLIMO POPS...WHICH WITH THIS FORECAST PACKAGE STILL
AMOUNT TO NO MENTION OF WEATHER FOR THURSDAY.

FRIDAY INTO NEXT WEEKEND...
PACIFIC RIDGING IS FORECAST TO BUILD ONSHORE OVER THE WEST
COAST...KEEPING DRY NORTH TO NORTHEASTERLY FLOW ACROSS THE AREA.
STILL A DECENT AMOUNT OF UNCERTAINTY /MOSTLY TIMING BASED/ WITH THE
STORM TRACK FOR THE WEEKEND...WITH ALL THE MEDIUM RANGE MODELS
SHOWING THE RIDGE HEIGHTS FALLING AND WEAK AND GENERALLY DRY
SHORTWAVES BEGINNING TO MOVE THROUGH THE REGION DURING THE
WEEKEND.

&&

AVIATION...
SOUTHEAST CALIFORNIA...SOUTHWEST AND SOUTH CENTRAL
ARIZONA...INCLUDING KPHX...KIWA...KIPL AND KBLH...

PERIODS OF HIGH CLOUDS...ACCOMPANIED BY LIGHT WINDS AT ALL TAF
SITES. WINDS WILL GENERALLY FOLLOW NORMAL DIURNAL TENDENCIES OVER
SOUTH CENTRAL AZ...AND FAVOR THE NORTH ALONG THE LOWER CO RIVER
VALLEY. VFR CONDITIONS ALL AIRFIELDS NEXT 24 HOURS. NO AVIATION
CONCERNS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
A LOW PRESSURE SYSTEM WILL BRING INCREASING MOISTURE AND A CHANCE OF
LIGHT PRECIPITATION TO SOUTHEASTERN CA AND SOUTHWESTERN AZ WED
MORNING. RAIN TOTALS WILL GENERALLY BE ONLY A FEW HUNDREDTHS OF AN
INCH. HIGH PRESSURE ALONG WITH WARMER AND DRIER CONDITIONS ARE
EXPECTED TO RETURN TO THE REGION FRIDAY INTO THE WEEKEND. WINDS
DURING THIS TIME FRAME WILL GENERALLY BE LIGHT...WITH SOME BREEZY
PERIODS MAINLY ACROSS SOUTHEASTERN CALIFORNIA THU.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE.

&&

$$

NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT

WEATHER.GOV/PHOENIX

DISCUSSION...NOLTE
AVIATION....AJ
FIRE WEATHER...HIRSCH

NWS PSR Office Area Forecast Discussion