Area Forecast Discussion
Issued by NWS San Diego, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KSGX 130439
AFDSGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
940 PM PDT SAT JUL 12 2014

.SYNOPSIS...
SIGHTLY WARMER FOR SUNDAY...DUE TO HIGH PRESSURE OVER THE GREAT
BASIN. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE LATE IN
THE DAY OVER AND EAST OF THE MOUNTAINS...AS MONSOON MOISTURE FILTERS
BACK IN SUNDAY AFTERNOON. GREATER SHOWER AND THUNDERSTORM COVERAGE
OVER THE MOUNTAINS AND DESERTS MONDAY AND TUESDAY...AS AN EASTERLY
WAVE PASSES OUR SOUTH AND WEST. SHOWER AND THUNDERSTORMS CHANCES
DECREASE RAPIDLY AFTER TUESDAY. NIGHT AND MORNING LOW CLOUDS
CONTINUE ALONG THE COAST.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING
ORANGE...SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN
BERNARDINO COUNTIES...

SCATTERED HIGH CLOUDS...CLEARLY VISIBLE ON SATELLITE THIS
EVENING...WILL CLEAR FROM SOUTH TO NORTH AS THE OVERNIGHT HOURS
PROGRESS. LOW STRATUS IS BEGINNING TO REBUILD ALONG THE COAST...AND
SHOULD PUSH INTO THE INLAND VALLEYS AGAIN TONIGHT. THE EASTERLY WAVE
THAT IS SLATED TO IMPACT OUR WEATHER BEGINNING LATE SUNDAY IS
CLEARLY VISIBLE ON WATER VAPOR IMAGERY OVER NORTH CENTRAL MEXICO.

FOR SUNDAY...GOOD CHANCE OF SEEING CIRRUS AGAIN ABOVE 500 MB...AS
THE REMNANT HIGH CLOUDS FROM TODAYS CONVECTION OVER NORTHERN MEXICO
AND AZ HITCHES A RIDE WITH THE PREVAILING EASTERLY FLOW ALOFT.
TEMPERATURES WILL ALSO BE SEVERAL DEGREES WARMER...WITH THE RIDGE
AXIS BUILDING OVER SOUTHERN CALIFORNIA TONIGHT AND SHIFTING TO THE
NORTH WEST DURING THE DAY ON SUNDAY. THIS SHIFT WILL BRING A MORE
EAST SOUTH-EASTERLY COMPONENT TO OUR UPPER LEVEL WINDS LATE
SUNDAY...ALLOWING MONSOON MOISTURE TO FILTER BACK INTO OUR AREA.
MODELS PROJECT PW VALUES OF 1.30 INCHES IN SAN DIEGO COUNTY TO 1.10
INCHES THE UPPER DESERTS BY SUNDAY EVENING. GIVEN THESE PW
VALUES...ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AFTER
20Z SUNDAY AFTERNOON FOR THE MOUNTAINS EASTWARD...ASSUMING ADEQUATE
INSTABILITY EXISTS.

MODELS HAVE CONTINUED TO WAVER A LITTLE WITH THE TRACK OF EASTERLY
WAVE CURRENTLY OVER CENTRAL MEXICO. THIS BEING SAID...EXPECT THE
WAVE TO BE IN THE VICINITY OF NORTH CENTRAL BAJA MONDAY
AFTERNOON...WITH EAST SOUTH-EASTERLY FLOW INCREASING PW VALUES TO
BETWEEN 1.50 AND 2.00 INCHES. OVERALL...CHANCES FOR THUNDERSTORMS
LOOK GOOD FOR MONDAY AFTERNOON WITH THIS PATTERN...BUT COVERAGE AND
INTENSITY WILL BE HEAVILY DEPENDENT ON THE ULTIMATE TRACK OF THE
WAVE. THE PERSISTENT EASTERLY COMPONENT TO THE FLOW BETWEEN 850 MB
AND 200 MB MONDAY ALSO CONTINUES TO SUGGEST THE POTENTIAL FOR A FEW
SHOWERS OVER VALLEYS LATE IN THE DAY. PARTICULARLY IF 850-700 MB
FLOW INCREASES. NOT CONFIDENT ENOUGH TO ADD ANY CHANCES WEST OF THE
MOUNTAINS INTO THE GRIDS AT THIS TIME.

AFTER MONDAY...THUNDERSTORMS COVERAGE IS MORE CHALLENGING TO
DIAGNOSE...WITH THE EASTERLY WAVE SHIFTING RAPIDLY TO OUR WEST.
GIVEN CURRENT THINKING ON THE TRACK OF THE WAVE...THUNDERSTORMS ARE
POSSIBLE AGAIN ON TUESDAY OVER THE MOUNTAINS AND DESERTS. GREATEST
COVERAGE MAY SHIFT TOWARD THE NORTHERN PART OF OUR CWA...ALONG WITH
MORE FAVORABLE FORCING AND MOISTURE.

MINIMAL CHANCE FOR THUNDERSTORMS MAY LINGER FOR THE MOUNTAINS AND
DESERTS WEDNESDAY...BUT COVERAGE IS LIKELY TO BE GREATLY REDUCED AS
MOISTURE BEGINS TO FADE OVER THE AREA.

&&

.AVIATION...
130300...LOW CLOUDS WILL MOVE ASHORE ACROSS COASTAL AIRPORTS THIS
EVENING AROUND 04-08Z AND SPREAD INTO WESTERN VALLEYS OVERNIGHT.
BASES WILL BE AROUND 1500 FEET MSL WITH TOPS AROUND 2000 FEET.
CLEARING BY 16-17Z SUNDAY. ISOLATED THUNDERSTORMS POSSIBLE MAINLY
OVER MOUNTAINS SUNDAY AFTERNOON WITH BASES AROUND 10000 FEET AND
TOPS UP TO 35000 FEET. OTHERWISE...VARIABLE HIGH CLOUDS AOA 20000
FEET AND UNRESTRICTED VIS THROUGH SUNDAY.

&&

.MARINE...
800 PM...NO HAZARDOUS MARINE WEATHER CONDITIONS EXPECTED THROUGH
THURSDAY.

&&

.BEACHES...
HIGH TIDES ARE EXPECTED TO BE NEAR TO SLIGHTLY ABOVE 7 FEET FOR THE
OPEN COASTLINE DURING THE EVENINGS THROUGH SUNDAY...WHICH COULD
RESULT IN LOCAL MINOR TIDAL OVERFLOW OF LOW-LYING BEACH AREAS. A
BEACH HAZARDS STATEMENT CONTINUES THROUGH SUNDAY EVENING...SEE
LAXCFWSGX.

&&

.SKYWARN...
SPOTTER ACTIVATION WILL NOT BE NEEDED AT THIS TIME...BUT MAY BE
NEEDED ON SUNDAY AFTERNOON.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...BEACH HAZARDS STATEMENT THROUGH SUNDAY EVENING FOR THE BEACHES
     IN THE ORANGE COUNTY COASTAL AREAS...SAN DIEGO COUNTY
     COASTAL AREAS.

PZ...NONE.

&&

$$

PUBLIC...BA/PALMER
AVIATION/MARINE...MM






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.