709
FXUS66 KMTR 151050
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
350 AM PDT TUE APR 15 2025
..NEW SYNOPSIS, SHORT TERM, LONG TERM, MARINE
SYNOPSIS
ISSUED AT 349 AM PDT TUE APR 15 2025
COOLER TEMPERATURES ARE FORECAST THROUGH THURSDAY AND WARMER WEATHER
RETURNING FOR THE WEEKEND. SLIGHT CHANCE FOR THUNDERSTORMS ON
WEDNESDAY, PRIMARILY FOR THE CENTRAL COAST AND SOUTHERN COASTAL
RANGE.
SHORT TERM
(TODAY AND TONIGHT)
ISSUED AT 349 AM PDT TUE APR 15 2025
SATELLITE IMAGERY SHOWS THE UPPER LEVEL LOW SPINNING WEST OF OF
SOUTHERN CA THIS MORNING. WATER VAPOR IMAGERY SHOWS RATHER DRY AIR
ACROSS MUCH OF THE LOWER LEVELS WITH MOISTURE INCREASING AS YOU GO
UP IN THE ATMOSPHERE. CONVECTIVE INGREDIENTS FOR TODAY, AND IN
PARTICULAR THIS MORNING, LOOK TO BE SLIGHTLY HEALTHIER THAN
TOMORROW; HOWEVER, BASED ON SOUNDINGS ACROSS THE AREA WE'LL NEED TO
OVERCOME THE DRY AIR AND CIN TO REALLY GET ANYTHING GOING. SHOULD IT
HAPPEN, WE MIGHT BE ABLE TO GET A FEW SHOWERS OR THUNDERSTORMS OUT
OF IT WITH LIGHTNING AND PERHAPS A FEW BOUTS OF GUSTY WINDS. A NOTE
ABOUT THE DRIER AIR, THAT INCREASES THE DCAPE VALUES PUTTING US
CLOSE TO 800 J/KG SUPPORTING STRONGER DOWNDRAFTS SHOULD SHOWERS OR
STORMS FORM. CONFIDENCE IS LOW ON THIS HAPPENING, THUS I OPTED TO
KEEP POP AND THE MENTION OF THUNDER OUT OF THE FORECAST FOR TODAY.
LONG TERM
(WEDNESDAY THROUGH MONDAY)
ISSUED AT 349 AM PDT TUE APR 15 2025
THE FORECAST LOOKS TO BE ON TRACK FOR THE LONG TERM, WITH THE MAIN
FEATURE BEING THE POSSIBILITY FOR ELEVATED THUNDERSTORMS ON
WEDNESDAY. LOW PRESSURE IS EXPECTED TO MOVE ONSHORE INTO SOUTHERN CA
SENDING A SLUG OF MOISTURE TO THE NORTH. THIS SHOULD HELP KICK UP
SHOWERS AND PERHAPS THUNDERSTORM OR TWO OVER THE CENTRAL COAST AND
OUR PORTION OF THE SOUTHERN COASTAL RANGE. LOOKING AT HI-RES
GUIDANCE AND SOUNDINGS, CAPE HAS QUITE THE RANGE OF POSSIBILITIES.
THE NAM AND THE HRRR ARE THE MOST AGGRESSIVE WITH UP TO 500 J/KG OF
MUCAPE. BUT WHEN YOU LOOK AT THE SOUNDINGS, THERE IS A LOT OF CIN TO
OVERCOME. KEPT THE MENTION OF THUNDER IN THE FORECAST OVER CENTRAL
COAST AND UP INTO THE DIABLO RANGE, THOUGH CONFIDENCE REMAINS ON THE
LOWER END.
HEADING INTO THURSDAY, A SECONDARY SYSTEM SLIDES INTO NORTHERN CA
FROM THE NORTH WHILE THE UPPER LOW OVER SOUTHERN CA MEANDERS EAST.
DRY WEATHER IS EXPECTED, WHICH MAY BE ACCOMPANIED ACCOMPANIED WITH
SOME BREEZIER WINDS. AN UPPER LEVEL HIGH BUILDS OVER THE EASTERN
PACIFIC DURING THIS TIME, WHICH WILL EVENTUALLY NOSE IN FOR FRIDAY
AND SATURDAY. MORE ZONAL TO WEAK TROUGHING IS EXPECTED BY SUNDAY.
COOLER TEMPERATURES PREVAIL THROUGH THURSDAY, WITH A WARMING TREND
EXPECTED FOR THE WEEKEND.
AVIATION
(06Z TAFS)
ISSUED AT 936 PM PDT MON APR 14 2025
MODERATE WINDS REDUCE INTO THE NIGHT BECOMING LIGHT. LOW CLOUDS ARE
ALREADY AFFECTING THE MONTEREY BAY TERMINALS AND HAF. THESE CLOUDS
WILL SLOWLY MOVE FARTHER INLAND OVERNIGHT AFFECTING MOST OF THE TAF
SITES. ADDITIONALLY, TERMINALS ALONG THE COAST AS WELL AS STS LOOK TO
HAVE CIGS FALL TO LIFR LEVELS WITH FOG AFFECTING THOSE SITES THROUGH
A GOOD PORTION OF TUESDAY MORNING. CLOUD COVER BEGINS TO ERODE IN
THE MID TO LATE MORNING, BUT WIDESPREAD CLEARING ISN'T EXPECTED
UNTIL TUESDAY AFTERNOON AS MODERATE WINDS BUILD AND HELP MIX OUT THE
CLOUD COVER. IFR CIGS RETURN INTO TUESDAY NIGHT AS WINDS REDUCE.
VICINITY OF SFO...VFR LASTS INTO EARLY TUESDAY. WINDS ARE REDUCING,
BECOMING LIGHT AND LOOM TO TURN SLIGHTLY MORE SOUTHERLY THROUGH THE
NIGHT AND INTO THE EARLY AFTERNOON. CIGS FILL OVER THE OAK AND THE
EASTERN PORTIONS OF THE SF BAY, BUT STRUGGLE TO CONSISTENTLY FILL
OVER SFO IN THE MID MORNING, BEFORE EXITING IN THE LATE MORNING.
WEST WINDS WILL INCREASE AGAIN INTO TUESDAY AFTERNOON, BUT ONLY TO
MODERATE SPEEDS BEFORE BECOMING LIGHT AGAIN INTO THAT NIGHT.
SFO BRIDGE APPROACH...SIMILAR TO SFO
MONTEREY BAY TERMINALS...MVFR CIGS HAVE FILLED OVER THE TERMINALS.
THESE CIGS LOWER TO IFR IN THE EARLY NIGHT. FOG AND LIFR CIGS ARE
EXPECTED INTO THE LATE NIGHT AND LAST THROUGH MUCH OF THE MORNING
WITH LIGHT WINDS. VFR RETURNS INTO TUESDAY AFTERNOON AS CIGS RETREAT
INTO THE BAY AND MODERATE WIND BUILD.
MARINE
(TODAY THROUGH SUNDAY)
ISSUED AT 349 AM PDT TUE APR 15 2025
LIGHT TO MODERATE WINDS LAST THROUGH MUCH OF THE WEEK. MODERATE
SEAS HOLD THROUGH MIDWEEK OR SO, AND THEN BUILD INTO THE LATTER
PORTION OF THE WORK WEEK. NORTHWESTERLY WINDS LOOK TO BECOME FRESH
FOR THE WEEKEND LEADING TO CONCERNS FOR SMALLER CRAFT.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...NONE.
SHORT TERM...KR
LONG TERM....KR
AVIATION...MURDOCK
MARINE...KR
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