Half Moon Bay CA WX RSS feed

Area Forecast Discussion

FXUS66 KMTR [Monterey CA] 190915 AFDMTR ∨

FXUS66 KMTR 190915
AFDMTR [HEAD]

National Weather Service San Francisco California 2:15am PDT Fri Apr 19 2024 ∨

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
215 AM PDT FRI APR 19 2024 [HEAD]

New synopsis, short term, long term. ∨

...NEW SYNOPSIS, SHORT TERM, LONG TERM... [DISC]

Synopsis. Issued at 2:15am PDT Friday April 19 2024 ∨

.SYNOPSIS...
ISSUED AT 215 AM PDT FRI APR 19 2024 [DISC]

Cooler conditions are expected today and tomorrow with light drizzle possible each morning. Temperatures rebound late weekend and early next week. A return to unsettled conditions arrives Tuesday and persist throughout late next week. ∨

COOLER CONDITIONS ARE EXPECTED TODAY AND TOMORROW WITH LIGHT DRIZZLE
POSSIBLE EACH MORNING. TEMPERATURES REBOUND LATE WEEKEND AND EARLY
NEXT WEEK. A RETURN TO UNSETTLED CONDITIONS ARRIVES TUESDAY AND
PERSIST THROUGHOUT LATE NEXT WEEK. [DISC]

Short term. (today and tonight) issued at 2:15am PDT Friday April 19 2024 ∨

.SHORT TERM...
(TODAY AND TONIGHT)
ISSUED AT 215 AM PDT FRI APR 19 2024 [DISC]

A well defined marine layer is in place this morning (around 1800–2000 ft per Fort Ord profiler [instrument designed to measure horizontal winds directly above its location, and thus measure the vertical wind profile. Profilers operate on the same principles as Doppler radar.]) and will support patchy drizzle in the upslope regions this morning. Otherwise, this afternoon sunny conditions will return to inland areas with temperatures expected to warm into the low to mid 70s. Meanwhile, the coast remains in the upper 50s to mid 60s under mostly cloudy conditions. ∨

A WELL DEFINED MARINE LAYER IS IN PLACE THIS MORNING (AROUND 1800-
2000 FT PER FORT ORD PROFILER) AND WILL SUPPORT PATCHY DRIZZLE IN
THE UPSLOPE REGIONS THIS MORNING. OTHERWISE, THIS AFTERNOON SUNNY
CONDITIONS WILL RETURN TO INLAND AREAS WITH TEMPERATURES EXPECTED TO
WARM INTO THE LOW TO MID 70S. MEANWHILE, THE COAST REMAINS IN THE
UPPER 50S TO MID 60S UNDER MOSTLY CLOUDY CONDITIONS. [DISC]

Tonight, expecting clouds to make a return back inland and become more widespread with low temperatures in the upper 40s to lower 50s. Again, patchy drizzle will once again be possible. Saturday will feature slightly warmer temperatures inland, but only by a few degrees. Wind will also be on the increase with breezy northwest winds near the coast, in the coastal hills, and into the region's valleys. Looking for gusts of 25–35 mph in these areas by Saturday afternoon. ∨

TONIGHT, EXPECTING CLOUDS TO MAKE A RETURN BACK INLAND AND BECOME
MORE WIDESPREAD WITH LOW TEMPERATURES IN THE UPPER 40S TO LOWER 50S.
AGAIN, PATCHY DRIZZLE WILL ONCE AGAIN BE POSSIBLE. SATURDAY WILL
FEATURE SLIGHTLY WARMER TEMPERATURES INLAND, BUT ONLY BY A FEW
DEGREES. WIND WILL ALSO BE ON THE INCREASE WITH BREEZY NORTHWEST
WINDS NEAR THE COAST, IN THE COASTAL HILLS, AND INTO THE REGION`S
VALLEYS. LOOKING FOR GUSTS OF 25-35 MPH IN THESE AREAS BY SATURDAY
AFTERNOON. [DISC]

Long term. (Saturday through Thursday) issued at 2:15am PDT Friday April 19 2024 ∨

.LONG TERM...
(SATURDAY THROUGH THURSDAY)
ISSUED AT 215 AM PDT FRI APR 19 2024 [DISC]

By Sunday and Monday, ridging dominates the pattern once again with interior areas warming to near 80° with 60s and 70s as one gets closer to the coast. By Tuesday, a change to more unsettled conditions return as an upper level low approaches the region. This pattern will persist throughout late week and points to possible wet weather during the latter half of the week. However, there is no major concerns for flooding and may end up being widespread light drizzle if not light rain. Temperatures also turn cooler with highs in the upper 50s at the coast and mid-to-upper 60s inland from Tuesday throughout late week. Stay tuned! ∨

BY SUNDAY AND MONDAY, RIDGING DOMINATES THE PATTERN ONCE AGAIN WITH
INTERIOR AREAS WARMING TO NEAR 80 DEGREES WITH 60S AND 70S AS ONE
GETS CLOSER TO THE COAST. BY TUESDAY, A CHANGE TO MORE UNSETTLED
CONDITIONS RETURN AS AN UPPER LEVEL LOW APPROACHES THE REGION. THIS
PATTERN WILL PERSIST THROUGHOUT LATE WEEK AND POINTS TO POSSIBLE WET
WEATHER DURING THE LATTER HALF OF THE WEEK. HOWEVER, THERE IS NO
MAJOR CONCERNS FOR FLOODING AND MAY END UP BEING WIDESPREAD LIGHT
DRIZZLE IF NOT LIGHT RAIN. TEMPERATURES ALSO TURN COOLER WITH HIGHS
IN THE UPPER 50S AT THE COAST AND MID-TO-UPPER 60S INLAND FROM
TUESDAY THROUGHOUT LATE WEEK. STAY TUNED! [DISC]

Aviation. (06Z [11pm PDT] TAFs [Terminal Aerodrome Forecasts]) issued at 11:14pm PDT Thursday April 18 2024 ∨

.AVIATION...
(06Z TAFS)
ISSUED AT 1114 PM PDT THU APR 18 2024 [AVIA]

A mix of predominantly LIFR [Low Instrument Flight Rules] and IFR [Instrument Flight Rules] conditions through the night tonight and the late morning of Friday. North Bay and Monterey Bay terminals are likely to see LIFR [Low Instrument Flight Rules] conditions persisting through the overnight hours and into the late morning as a result of fog and low stratus ceilings. Sinking, drier air aloft is likely helping to lower and squash ceilings down to around 1400 feet currently per the Bodega Bay profiler [instrument designed to measure horizontal winds directly above its location, and thus measure the vertical wind profile. Profilers operate on the same principles as Doppler radar.], and 1800 feet per the Fort Ord profiler [instrument designed to measure horizontal winds directly above its location, and thus measure the vertical wind profile. Profilers operate on the same principles as Doppler radar.]. Expect these ceilings to lower progressively through the night and into the morning hours. Terminals in the SF Bay region are more likely to see MVFR [Marginal Visual Flight Rules] conditions per model suggestions, though confidence on this is only moderate, given the low ceilings elsewhere. A drop into IFR [Instrument Flight Rules] ceilings for SF Bay terminals overnight is not out of the question. Decent onshore flow overnight will also be a factor in helping advect stratus inland, leading to robust cloud coverage through at least the late morning of Friday. In the early afternoon, as things heat up, clouds should begin to mix out bringing a return of VFR [Visual Flight Rules] conditions and breezy to moderate onshore winds. ∨

A MIX OF PREDOMINANTLY LIFR AND IFR CONDITIONS THROUGH THE NIGHT
TONIGHT AND THE LATE MORNING OF FRIDAY. NORTH BAY AND MONTEREY BAY
TERMINALS ARE LIKELY TO SEE LIFR CONDITIONS PERSISTING THROUGH THE
OVERNIGHT HOURS AND INTO THE LATE MORNING AS A RESULT OF FOG AND LOW
STRATUS CIGS. SINKING, DRIER AIR ALOFT IS LIKELY HELPING TO LOWER
AND SQUASH CIGS DOWN TO AROUND 1400 FEET CURRENTLY PER THE BODEGA
BAY PROFILER, AND 1800 FEET PER THE FT. ORD PROFILER. EXPECT THESE
CIGS TO LOWER PROGRESSIVELY THROUGH THE NIGHT AND INTO THE MORNING
HOURS. TERMINALS IN THE SF BAY REGION ARE MORE LIKELY TO SEE MVFR
CONDITIONS PER MODEL SUGGESTIONS, THOUGH CONFIDENCE ON THIS IS ONLY
MODERATE, GIVEN THE LOW CIGS ELSEWHERE. A DROP INTO IFR CIGS FOR SF
BAY TERMINALS OVERNIGHT IS NOT OUT OF THE QUESTION. DECENT ONSHORE
FLOW OVERNIGHT WILL ALSO BE A FACTOR IN HELPING ADVECT STRATUS
INLAND, LEADING TO ROBUST CLOUD COVERAGE THROUGH AT LEAST THE LATE
MORNING OF FRIDAY. IN THE EARLY AFTERNOON, AS THINGS HEAT UP, CLOUDS
SHOULD BEGIN TO MIX OUT BRINGING A RETURN OF VFR CONDITIONS AND
BREEZY TO MODERATE ONSHORE WINDS. [AVI2]

Vicinity of SFO [San Francisco CA]… SFO [San Francisco CA] in particular overnight appears to remain the odd one out, as it is likely to remain in VFR [Visual Flight Rules] Territory, with good agreement among numerous models. Despite good onshore flow overnight around 6–7 knots [7–8 mph], given the fact that the stratus deck currently sits around 1400' and is expected to lower, stratus may not be able to rise above and advect through the San Bruno Gap, keeping conditions clear and VFR [Visual Flight Rules] locally at SFO [San Francisco CA] terminal. Additionally, any stratus that fills over the Bay waters will be likely kept just on the periphery of the SFO [San Francisco CA] vicinity as good overnight flow out of the west helps keep any stratus over the Bay away and pushed more towards the KOAK [Oakland CA] side. KOAK [Oakland CA] conversely will likely see IFR [Instrument Flight Rules] conditions last through the nighttime as good overnight onshore flow helps push stratus through the Golden Gate Gap and into the SF Bay. Late clearing is expected at KOAK [Oakland CA] with VFR [Visual Flight Rules] returning in the late morning to early afternoon. ∨

VICINITY OF SFO...SFO IN PARTICULAR OVERNIGHT APPEARS TO REMAIN THE
ODD ONE OUT, AS IT IS LIKELY TO REMAIN IN VFR TERRITORY, WITH GOOD
AGREEMENT AMONG NUMEROUS MODELS. DESPITE GOOD ONSHORE FLOW OVERNIGHT
AROUND 6-7 KNOTS, GIVEN THE FACT THAT THE STRATUS DECK CURRENTLY
SITS AROUND 1400` AND IS EXPECTED TO LOWER, STRATUS MAY NOT BE ABLE
TO RISE ABOVE AND ADVECT THROUGH THE SAN BRUNO GAP, KEEPING
CONDITIONS CLEAR AND VFR LOCALLY AT SFO TERMINAL. ADDITIONALLY, ANY
STRATUS THAT FILLS OVER THE BAY WATERS WILL BE LIKELY KEPT JUST ON
THE PERIPHERY OF THE SFO VICINITY AS GOOD OVERNIGHT FLOW OUT OF
THE WEST HELPS KEEP ANY STRATUS OVER THE BAY AWAY AND PUSHED MORE
TOWARDS THE KOAK SIDE. KOAK CONVERSELY WILL LIKELY SEE IFR
CONDITIONS LAST THROUGH THE NIGHTTIME AS GOOD OVERNIGHT ONSHORE
FLOW HELPS PUSH STRATUS THROUGH THE GOLDEN GATE GAP AND INTO THE
SF BAY. LATE CLEARING IS EXPECTED AT KOAK WITH VFR RETURNING IN
THE LATE MORNING TO EARLY AFTERNOON. [AVI2]

SFO [San Francisco CA] bridge approach… IFR [Instrument Flight Rules]-LIFR [Low Instrument Flight Rules] conditions are likely as robust stratus coverage develops overnight over the SF Bay waters thanks to good onshore flow. Clearing expected into the very late morning to early afternoon of Friday to VFR [Visual Flight Rules]. ∨

SFO BRIDGE APPROACH...IFR-LIFR CONDITIONS ARE LIKELY AS ROBUST
STRATUS COVERAGE DEVELOPS OVERNIGHT OVER THE SF BAY WATERS THANKS TO
GOOD ONSHORE FLOW. CLEARING EXPECTED INTO THE VERY LATE MORNING TO
EARLY AFTERNOON OF FRIDAY TO VFR. [AVI2]

Monterey Bay terminals… IFR [Instrument Flight Rules]/LIFR [Low Instrument Flight Rules] through much of the night as a result of very low ceilings. Stratus is expected to continue to lower through the night. Some reductions in visibility are possible as ceilings lower and the air reaches saturation near the ground, leading to mist and fog development. However, confidence on mist and fog development is not as strong as confidence in ceilings lowering. This will be something to watch closely overnight. VFR [Visual Flight Rules] returns in the early afternoon though a few-scattered low clouds may linger, with winds onshore and around 10 knots [12 mph]. Stratus makes an early return in the evening of Friday. ∨

MONTEREY BAY TERMINALS...IFR/LIFR THROUGH MUCH OF THE NIGHT AS A
RESULT OF VERY LOW CIGS. STRATUS IS EXPECTED TO CONTINUE TO LOWER
THROUGH THE NIGHT. SOME REDUCTIONS IN VISIBILITY ARE POSSIBLE AS
CIGS LOWER AND THE AIR REACHES SATURATION NEAR THE GROUND, LEADING
TO MIST AND FOG DEVELOPMENT. HOWEVER, CONFIDENCE ON MIST AND FOG
DEVELOPMENT IS NOT AS STRONG AS CONFIDENCE IN CIGS LOWERING. THIS
WILL BE SOMETHING TO WATCH CLOSELY OVERNIGHT. VFR RETURNS IN THE
EARLY AFTERNOON THOUGH A FEW-SCT LOW CLOUDS MAY LINGER, WITH WINDS
ONSHORE AND AROUND 10 KNOTS. STRATUS MAKES AN EARLY RETURN IN THE
EVENING OF FRIDAY. [AVI2]

Marine. (tonight through next Wednesday) issued at 11:14pm PDT Thursday April 18 2024 ∨

.MARINE...
(TONIGHT THROUGH NEXT WEDNESDAY)
ISSUED AT 1114 PM PDT THU APR 18 2024 [AVIA]

Expect light to moderate winds into the weekend before breezy to gusty northerly winds arrive Saturday afternoon that will increase hazardous conditions over the waters. Wave heights will start to build heading into the late weekend before diminishing by mid-week. Another moderate period northwest swell arrives over the weekend as well as another light, longer period (18 seconds) southerly swell. ∨

EXPECT LIGHT TO MODERATE WINDS INTO THE WEEKEND BEFORE BREEZY TO
GUSTY NORTHERLY WINDS ARRIVE SATURDAY AFTERNOON THAT WILL INCREASE
HAZARDOUS CONDITIONS OVER THE WATERS. WAVE HEIGHTS WILL START TO
BUILD HEADING INTO THE LATE WEEKEND BEFORE DIMINISHING BY MID-
WEEK. ANOTHER MODERATE PERIOD NORTHWEST SWELL ARRIVES OVER THE
WEEKEND AS WELL AS ANOTHER LIGHT, LONGER PERIOD (18 SECONDS)
SOUTHERLY SWELL. [AVI2]

MTR Watches/Warnings/Advisories

California: none.
Pacific Ocean: none. ∨

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE. [WARN]

Short term…rgass long term…rgass aviation…altocumulus marine…so ∨

SHORT TERM...RGASS
LONG TERM....RGASS
AVIATION...AC
MARINE...SO [WRN2]

VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO [LINK]

Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea ∨

FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA [DISC]

Weather NWS glossary About NWS point forecasts Hourly Weather Graph Long-range forecast Radar Satellite Max Temps Graphical Forecast	Area Forecast Discussion FXUS66 KMTR [Monterey CA] 190915 AFDMTR ∨ FXUS66 KMTR 190915 AFDMTR [HEAD] National Weather Service San Francisco California 2:15am PDT Fri Apr 19 2024 ∨ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN FRANCISCO CA 215 AM PDT FRI APR 19 2024 [HEAD] New synopsis, short term, long term. ∨ ...NEW SYNOPSIS, SHORT TERM, LONG TERM... [DISC] Synopsis. Issued at 2:15am PDT Friday April 19 2024 ∨ .SYNOPSIS... ISSUED AT 215 AM PDT FRI APR 19 2024 [DISC] Cooler conditions are expected today and tomorrow with light drizzle possible each morning. Temperatures rebound late weekend and early next week. A return to unsettled conditions arrives Tuesday and persist throughout late next week. ∨ COOLER CONDITIONS ARE EXPECTED TODAY AND TOMORROW WITH LIGHT DRIZZLE POSSIBLE EACH MORNING. TEMPERATURES REBOUND LATE WEEKEND AND EARLY NEXT WEEK. A RETURN TO UNSETTLED CONDITIONS ARRIVES TUESDAY AND PERSIST THROUGHOUT LATE NEXT WEEK. [DISC] Short term. (today and tonight) issued at 2:15am PDT Friday April 19 2024 ∨ .SHORT TERM... (TODAY AND TONIGHT) ISSUED AT 215 AM PDT FRI APR 19 2024 [DISC] A well defined marine layer is in place this morning (around 1800–2000 ft per Fort Ord profiler [instrument designed to measure horizontal winds directly above its location, and thus measure the vertical wind profile. Profilers operate on the same principles as Doppler radar.]) and will support patchy drizzle in the upslope regions this morning. Otherwise, this afternoon sunny conditions will return to inland areas with temperatures expected to warm into the low to mid 70s. Meanwhile, the coast remains in the upper 50s to mid 60s under mostly cloudy conditions. ∨ A WELL DEFINED MARINE LAYER IS IN PLACE THIS MORNING (AROUND 1800- 2000 FT PER FORT ORD PROFILER) AND WILL SUPPORT PATCHY DRIZZLE IN THE UPSLOPE REGIONS THIS MORNING. OTHERWISE, THIS AFTERNOON SUNNY CONDITIONS WILL RETURN TO INLAND AREAS WITH TEMPERATURES EXPECTED TO WARM INTO THE LOW TO MID 70S. MEANWHILE, THE COAST REMAINS IN THE UPPER 50S TO MID 60S UNDER MOSTLY CLOUDY CONDITIONS. [DISC] Tonight, expecting clouds to make a return back inland and become more widespread with low temperatures in the upper 40s to lower 50s. Again, patchy drizzle will once again be possible. Saturday will feature slightly warmer temperatures inland, but only by a few degrees. Wind will also be on the increase with breezy northwest winds near the coast, in the coastal hills, and into the region's valleys. Looking for gusts of 25–35 mph in these areas by Saturday afternoon. ∨ TONIGHT, EXPECTING CLOUDS TO MAKE A RETURN BACK INLAND AND BECOME MORE WIDESPREAD WITH LOW TEMPERATURES IN THE UPPER 40S TO LOWER 50S. AGAIN, PATCHY DRIZZLE WILL ONCE AGAIN BE POSSIBLE. SATURDAY WILL FEATURE SLIGHTLY WARMER TEMPERATURES INLAND, BUT ONLY BY A FEW DEGREES. WIND WILL ALSO BE ON THE INCREASE WITH BREEZY NORTHWEST WINDS NEAR THE COAST, IN THE COASTAL HILLS, AND INTO THE REGION`S VALLEYS. LOOKING FOR GUSTS OF 25-35 MPH IN THESE AREAS BY SATURDAY AFTERNOON. [DISC] Long term. (Saturday through Thursday) issued at 2:15am PDT Friday April 19 2024 ∨ .LONG TERM... (SATURDAY THROUGH THURSDAY) ISSUED AT 215 AM PDT FRI APR 19 2024 [DISC] By Sunday and Monday, ridging dominates the pattern once again with interior areas warming to near 80° with 60s and 70s as one gets closer to the coast. By Tuesday, a change to more unsettled conditions return as an upper level low approaches the region. This pattern will persist throughout late week and points to possible wet weather during the latter half of the week. However, there is no major concerns for flooding and may end up being widespread light drizzle if not light rain. Temperatures also turn cooler with highs in the upper 50s at the coast and mid-to-upper 60s inland from Tuesday throughout late week. Stay tuned! ∨ BY SUNDAY AND MONDAY, RIDGING DOMINATES THE PATTERN ONCE AGAIN WITH INTERIOR AREAS WARMING TO NEAR 80 DEGREES WITH 60S AND 70S AS ONE GETS CLOSER TO THE COAST. BY TUESDAY, A CHANGE TO MORE UNSETTLED CONDITIONS RETURN AS AN UPPER LEVEL LOW APPROACHES THE REGION. THIS PATTERN WILL PERSIST THROUGHOUT LATE WEEK AND POINTS TO POSSIBLE WET WEATHER DURING THE LATTER HALF OF THE WEEK. HOWEVER, THERE IS NO MAJOR CONCERNS FOR FLOODING AND MAY END UP BEING WIDESPREAD LIGHT DRIZZLE IF NOT LIGHT RAIN. TEMPERATURES ALSO TURN COOLER WITH HIGHS IN THE UPPER 50S AT THE COAST AND MID-TO-UPPER 60S INLAND FROM TUESDAY THROUGHOUT LATE WEEK. STAY TUNED! [DISC] Aviation. (06Z [11pm PDT] TAFs [Terminal Aerodrome Forecasts]) issued at 11:14pm PDT Thursday April 18 2024 ∨ .AVIATION... (06Z TAFS) ISSUED AT 1114 PM PDT THU APR 18 2024 [AVIA] A mix of predominantly LIFR [Low Instrument Flight Rules] and IFR [Instrument Flight Rules] conditions through the night tonight and the late morning of Friday. North Bay and Monterey Bay terminals are likely to see LIFR [Low Instrument Flight Rules] conditions persisting through the overnight hours and into the late morning as a result of fog and low stratus ceilings. Sinking, drier air aloft is likely helping to lower and squash ceilings down to around 1400 feet currently per the Bodega Bay profiler [instrument designed to measure horizontal winds directly above its location, and thus measure the vertical wind profile. Profilers operate on the same principles as Doppler radar.], and 1800 feet per the Fort Ord profiler [instrument designed to measure horizontal winds directly above its location, and thus measure the vertical wind profile. Profilers operate on the same principles as Doppler radar.]. Expect these ceilings to lower progressively through the night and into the morning hours. Terminals in the SF Bay region are more likely to see MVFR [Marginal Visual Flight Rules] conditions per model suggestions, though confidence on this is only moderate, given the low ceilings elsewhere. A drop into IFR [Instrument Flight Rules] ceilings for SF Bay terminals overnight is not out of the question. Decent onshore flow overnight will also be a factor in helping advect stratus inland, leading to robust cloud coverage through at least the late morning of Friday. In the early afternoon, as things heat up, clouds should begin to mix out bringing a return of VFR [Visual Flight Rules] conditions and breezy to moderate onshore winds. ∨ A MIX OF PREDOMINANTLY LIFR AND IFR CONDITIONS THROUGH THE NIGHT TONIGHT AND THE LATE MORNING OF FRIDAY. NORTH BAY AND MONTEREY BAY TERMINALS ARE LIKELY TO SEE LIFR CONDITIONS PERSISTING THROUGH THE OVERNIGHT HOURS AND INTO THE LATE MORNING AS A RESULT OF FOG AND LOW STRATUS CIGS. SINKING, DRIER AIR ALOFT IS LIKELY HELPING TO LOWER AND SQUASH CIGS DOWN TO AROUND 1400 FEET CURRENTLY PER THE BODEGA BAY PROFILER, AND 1800 FEET PER THE FT. ORD PROFILER. EXPECT THESE CIGS TO LOWER PROGRESSIVELY THROUGH THE NIGHT AND INTO THE MORNING HOURS. TERMINALS IN THE SF BAY REGION ARE MORE LIKELY TO SEE MVFR CONDITIONS PER MODEL SUGGESTIONS, THOUGH CONFIDENCE ON THIS IS ONLY MODERATE, GIVEN THE LOW CIGS ELSEWHERE. A DROP INTO IFR CIGS FOR SF BAY TERMINALS OVERNIGHT IS NOT OUT OF THE QUESTION. DECENT ONSHORE FLOW OVERNIGHT WILL ALSO BE A FACTOR IN HELPING ADVECT STRATUS INLAND, LEADING TO ROBUST CLOUD COVERAGE THROUGH AT LEAST THE LATE MORNING OF FRIDAY. IN THE EARLY AFTERNOON, AS THINGS HEAT UP, CLOUDS SHOULD BEGIN TO MIX OUT BRINGING A RETURN OF VFR CONDITIONS AND BREEZY TO MODERATE ONSHORE WINDS. [AVI2] Vicinity of SFO [San Francisco CA]… SFO [San Francisco CA] in particular overnight appears to remain the odd one out, as it is likely to remain in VFR [Visual Flight Rules] Territory, with good agreement among numerous models. Despite good onshore flow overnight around 6–7 knots [7–8 mph], given the fact that the stratus deck currently sits around 1400' and is expected to lower, stratus may not be able to rise above and advect through the San Bruno Gap, keeping conditions clear and VFR [Visual Flight Rules] locally at SFO [San Francisco CA] terminal. Additionally, any stratus that fills over the Bay waters will be likely kept just on the periphery of the SFO [San Francisco CA] vicinity as good overnight flow out of the west helps keep any stratus over the Bay away and pushed more towards the KOAK [Oakland CA] side. KOAK [Oakland CA] conversely will likely see IFR [Instrument Flight Rules] conditions last through the nighttime as good overnight onshore flow helps push stratus through the Golden Gate Gap and into the SF Bay. Late clearing is expected at KOAK [Oakland CA] with VFR [Visual Flight Rules] returning in the late morning to early afternoon. ∨ VICINITY OF SFO...SFO IN PARTICULAR OVERNIGHT APPEARS TO REMAIN THE ODD ONE OUT, AS IT IS LIKELY TO REMAIN IN VFR TERRITORY, WITH GOOD AGREEMENT AMONG NUMEROUS MODELS. DESPITE GOOD ONSHORE FLOW OVERNIGHT AROUND 6-7 KNOTS, GIVEN THE FACT THAT THE STRATUS DECK CURRENTLY SITS AROUND 1400` AND IS EXPECTED TO LOWER, STRATUS MAY NOT BE ABLE TO RISE ABOVE AND ADVECT THROUGH THE SAN BRUNO GAP, KEEPING CONDITIONS CLEAR AND VFR LOCALLY AT SFO TERMINAL. ADDITIONALLY, ANY STRATUS THAT FILLS OVER THE BAY WATERS WILL BE LIKELY KEPT JUST ON THE PERIPHERY OF THE SFO VICINITY AS GOOD OVERNIGHT FLOW OUT OF THE WEST HELPS KEEP ANY STRATUS OVER THE BAY AWAY AND PUSHED MORE TOWARDS THE KOAK SIDE. KOAK CONVERSELY WILL LIKELY SEE IFR CONDITIONS LAST THROUGH THE NIGHTTIME AS GOOD OVERNIGHT ONSHORE FLOW HELPS PUSH STRATUS THROUGH THE GOLDEN GATE GAP AND INTO THE SF BAY. LATE CLEARING IS EXPECTED AT KOAK WITH VFR RETURNING IN THE LATE MORNING TO EARLY AFTERNOON. [AVI2] SFO [San Francisco CA] bridge approach… IFR [Instrument Flight Rules]-LIFR [Low Instrument Flight Rules] conditions are likely as robust stratus coverage develops overnight over the SF Bay waters thanks to good onshore flow. Clearing expected into the very late morning to early afternoon of Friday to VFR [Visual Flight Rules]. ∨ SFO BRIDGE APPROACH...IFR-LIFR CONDITIONS ARE LIKELY AS ROBUST STRATUS COVERAGE DEVELOPS OVERNIGHT OVER THE SF BAY WATERS THANKS TO GOOD ONSHORE FLOW. CLEARING EXPECTED INTO THE VERY LATE MORNING TO EARLY AFTERNOON OF FRIDAY TO VFR. [AVI2] Monterey Bay terminals… IFR [Instrument Flight Rules]/LIFR [Low Instrument Flight Rules] through much of the night as a result of very low ceilings. Stratus is expected to continue to lower through the night. Some reductions in visibility are possible as ceilings lower and the air reaches saturation near the ground, leading to mist and fog development. However, confidence on mist and fog development is not as strong as confidence in ceilings lowering. This will be something to watch closely overnight. VFR [Visual Flight Rules] returns in the early afternoon though a few-scattered low clouds may linger, with winds onshore and around 10 knots [12 mph]. Stratus makes an early return in the evening of Friday. ∨ MONTEREY BAY TERMINALS...IFR/LIFR THROUGH MUCH OF THE NIGHT AS A RESULT OF VERY LOW CIGS. STRATUS IS EXPECTED TO CONTINUE TO LOWER THROUGH THE NIGHT. SOME REDUCTIONS IN VISIBILITY ARE POSSIBLE AS CIGS LOWER AND THE AIR REACHES SATURATION NEAR THE GROUND, LEADING TO MIST AND FOG DEVELOPMENT. HOWEVER, CONFIDENCE ON MIST AND FOG DEVELOPMENT IS NOT AS STRONG AS CONFIDENCE IN CIGS LOWERING. THIS WILL BE SOMETHING TO WATCH CLOSELY OVERNIGHT. VFR RETURNS IN THE EARLY AFTERNOON THOUGH A FEW-SCT LOW CLOUDS MAY LINGER, WITH WINDS ONSHORE AND AROUND 10 KNOTS. STRATUS MAKES AN EARLY RETURN IN THE EVENING OF FRIDAY. [AVI2] Marine. (tonight through next Wednesday) issued at 11:14pm PDT Thursday April 18 2024 ∨ .MARINE... (TONIGHT THROUGH NEXT WEDNESDAY) ISSUED AT 1114 PM PDT THU APR 18 2024 [AVIA] Expect light to moderate winds into the weekend before breezy to gusty northerly winds arrive Saturday afternoon that will increase hazardous conditions over the waters. Wave heights will start to build heading into the late weekend before diminishing by mid-week. Another moderate period northwest swell arrives over the weekend as well as another light, longer period (18 seconds) southerly swell. ∨ EXPECT LIGHT TO MODERATE WINDS INTO THE WEEKEND BEFORE BREEZY TO GUSTY NORTHERLY WINDS ARRIVE SATURDAY AFTERNOON THAT WILL INCREASE HAZARDOUS CONDITIONS OVER THE WATERS. WAVE HEIGHTS WILL START TO BUILD HEADING INTO THE LATE WEEKEND BEFORE DIMINISHING BY MID- WEEK. ANOTHER MODERATE PERIOD NORTHWEST SWELL ARRIVES OVER THE WEEKEND AS WELL AS ANOTHER LIGHT, LONGER PERIOD (18 SECONDS) SOUTHERLY SWELL. [AVI2] MTR Watches/Warnings/Advisories California: none. Pacific Ocean: none. ∨ .MTR WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. [WARN] Short term…rgass long term…rgass aviation…altocumulus marine…so ∨ SHORT TERM...RGASS LONG TERM....RGASS AVIATION...AC MARINE...SO [WRN2] VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO [LINK] Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea ∨ FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA [DISC]	Point Forecast Half Moon Bay CA 19 Apr 01:55am PDT Overnight A slight chance of drizzle. Cloudy, with a low around 45°. SSW wind around 6 mph. Friday A slight chance of drizzle. Mostly cloudy, then gradually becoming sunny, with a high near 61°. SSW wind 6 to 10 mph. Friday Night A slight chance of drizzle after 11pm. Mostly cloudy, with a low around 45°. WSW wind 5 to 7 mph. Saturday Mostly sunny, with a high near 63°. West wind 7 to 11 mph, with gusts as high as 18 mph. Saturday Night Partly cloudy, with a low around 46°. NW wind 11 to 14 mph, with gusts as high as 22 mph. Sunday Sunny, with a high near 65°. Sunday Night Mostly clear, with a low around 47°. Monday Mostly sunny, with a high near 67°. Monday Night Partly cloudy, with a low around 47°. Tuesday Partly sunny, with a high near 61°. Tuesday Night Mostly cloudy, with a low around 47°. Wednesday Partly sunny, with a high near 60°. Wednesday Night Mostly cloudy, with a low around 46°. Thursday Partly sunny, with a high near 58°. Overnight A slight chance of drizzle. Cloudy, with a low around 45. South southwest wind around 6 mph. Friday A slight chance of drizzle. Mostly cloudy, then gradually becoming sunny, with a high near 61. South southwest wind 6 to 10 mph. Friday Night A slight chance of drizzle after 11pm. Mostly cloudy, with a low around 45. West southwest wind 5 to 7 mph. Saturday Mostly sunny, with a high near 63. West wind 7 to 11 mph, with gusts as high as 18 mph. Saturday Night Partly cloudy, with a low around 46. Northwest wind 11 to 14 mph, with gusts as high as 22 mph. Sunday Sunny, with a high near 65. Sunday Night Mostly clear, with a low around 47. Monday Mostly sunny, with a high near 67. Monday Night Partly cloudy, with a low around 47. Tuesday Partly sunny, with a high near 61. Tuesday Night Mostly cloudy, with a low around 47. Wednesday Partly sunny, with a high near 60. Wednesday Night Mostly cloudy, with a low around 46. Thursday Partly sunny, with a high near 58.
This page is generated dynamically from the National Weather Service's NWS point forecast and Area Forecast Discussion, reformatted for readability. NWS glossary; about point forecasts. For more information, visit the Lobitos Weather Project home page. Comments and corrections are welcome: