Area Forecast Discussion
FXUS66 KMTR [Monterey CA] 272340 AFDMTR ∨
FXUS66 KMTR 272340 AFDMTR [HEAD]
National Weather Service San Francisco Bay Area 4:40pm PDT Wed May 27 2015 ∨
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA 440 PM PDT WED MAY 27 2015 [HEAD]
Synopsis. High pressure building along the West Coast will result in a modest warming trend through Saturday… most apparent inland. Temperatures then cool Sunday into early next week as a weak upper level trough approaches the coast. While a slight chance of showers will be possible over the North Bay Sunday night into Monday… most locations will remain dry through the forecast period. ∨
.SYNOPSIS...HIGH PRESSURE BUILDING ALONG THE WEST COAST WILL RESULT IN A MODEST WARMING TREND THROUGH SATURDAY...MOST APPARENT INLAND. TEMPERATURES THEN COOL SUNDAY INTO EARLY NEXT WEEK AS A WEAK UPPER LEVEL TROUGH APPROACHES THE COAST. WHILE A SLIGHT CHANCE OF SHOWERS WILL BE POSSIBLE OVER THE NORTH BAY SUNDAY NIGHT INTO MONDAY...MOST LOCATIONS WILL REMAIN DRY THROUGH THE FORECAST PERIOD. [DISC]
Discussion. As of 02:39pm PDT Wednesday… the deep marine layer that has impacted the region during the past several days is showing sings of compressing on 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.] this afternoon. Meanwhile… a weak mid/upper level ridge off of the coast is forecast to build inland through late week. This should result in less inland penetration of low clouds over the next few days… yet the presence of the marine layer will likely result in at least coastal clouds during the late evening - morning hours. In addition… with warming 850 mb temperatures as a result of the building high pressure… inland surface temperatures will continue on a warming trend. By Friday and Saturday… inland locations will likely warm into the 80s region-wide with a few spots reaching 90°. While coastal areas will also see a warming trend… temperatures there will likely remain in the 60s through late week. ∨
.DISCUSSION...AS OF 02:39 PM PDT WEDNESDAY...THE DEEP MARINE LAYER THAT HAS IMPACTED THE REGION DURING THE PAST SEVERAL DAYS IS SHOWING SINGS OF COMPRESSING ON THE FORT ORD PROFILER THIS AFTERNOON. MEANWHILE...A WEAK MID/UPPER LEVEL RIDGE OFF OF THE COAST IS FORECAST TO BUILD INLAND THROUGH LATE WEEK. THIS SHOULD RESULT IN LESS INLAND PENETRATION OF LOW CLOUDS OVER THE NEXT FEW DAYS...YET THE PRESENCE OF THE MARINE LAYER WILL LIKELY RESULT IN AT LEAST COASTAL CLOUDS DURING THE LATE EVENING - MORNING HOURS. IN ADDITION...WITH WARMING 850MB TEMPERATURES AS A RESULT OF THE BUILDING HIGH PRESSURE...INLAND SURFACE TEMPERATURES WILL CONTINUE ON A WARMING TREND. BY FRIDAY AND SATURDAY...INLAND LOCATIONS WILL LIKELY WARM INTO THE 80S REGION-WIDE WITH A FEW SPOTS REACHING 90 DEGREES. WHILE COASTAL AREAS WILL ALSO SEE A WARMING TREND...TEMPERATURES THERE WILL LIKELY REMAIN IN THE 60S THROUGH LATE WEEK. [DISC]
Temperatures begin to cool Sunday in advance of an approaching mid/upper level trough. As the weak system moves inland… there will be a slight chance of showers across the North Bay Sunday night into Monday. This area is where the models show the best moisture availability while areas to the south will likely remain dry. However… patchy drizzle cannot be ruled out along the coast Monday morning as the marine layer deepens in response to the passing system. The upper level low ejects toward the northeast with another ridge building over the region for the second half of next week. This will result in a slight warming trend and dry weather conditions likely for much of next week. ∨
TEMPERATURES BEGIN TO COOL SUNDAY IN ADVANCE OF AN APPROACHING MID/UPPER LEVEL TROUGH. AS THE WEAK SYSTEM MOVES INLAND...THERE WILL BE A SLIGHT CHANCE OF SHOWERS ACROSS THE NORTH BAY SUNDAY NIGHT INTO MONDAY. THIS AREA IS WHERE THE MODELS SHOW THE BEST MOISTURE AVAILABILITY WHILE AREAS TO THE SOUTH WILL LIKELY REMAIN DRY. HOWEVER...PATCHY DRIZZLE CANNOT BE RULED OUT ALONG THE COAST MONDAY MORNING AS THE MARINE LAYER DEEPENS IN RESPONSE TO THE PASSING SYSTEM. THE UPPER LEVEL LOW EJECTS TOWARD THE NORTHEAST WITH ANOTHER RIDGE BUILDING OVER THE REGION FOR THE SECOND HALF OF NEXT WEEK. THIS WILL RESULT IN A SLIGHT WARMING TREND AND DRY WEATHER CONDITIONS LIKELY FOR MUCH OF NEXT WEEK. [DISC]
Aviation. As of 4:39pm PDT Wednesday… coastal low clouds will be ushered inland by onshore winds again tonight. The marine layer has compressed a little since last evening and is roughly 2500 feet deep. The upper level ridge over the area will gradually strengthen during the period. ∨
.AVIATION...AS OF 4:39 PM PDT WEDNESDAY...COASTAL LOW CLOUDS WILL BE USHERED INLAND BY ONSHORE WINDS AGAIN TONIGHT. THE MARINE LAYER HAS COMPRESSED A LITTLE SINCE LAST EVENING AND IS ROUGHLY 2500 FEET DEEP. THE UPPER LEVEL RIDGE OVER THE AREA WILL GRADUALLY STRENGTHEN DURING THE PERIOD. [AVIA]
Vicinity of KSFO [San Francisco CA]… early stratus arrival at KSFO [San Francisco CA] with MVFR [Marginal Visual Flight Rules] ceiling reported since 2240Z [3:40pm PDT]. Continued stratus feed favored by westerly winds and a moderately deep marine layer. ∨
VICINITY OF KSFO...EARLY STRATUS ARRIVAL AT KSFO WITH MVFR CIG REPORTED SINCE 2240Z. CONTINUED STRATUS FEED FAVORED BY WESTERLY WINDS AND A MODERATELY DEEP MARINE LAYER. [AVI2]
KSFO [San Francisco CA] bridge approach… per coordinate with Oakland cwsu thought is that the stratus will reach the approach by approx 04Z [9pm PDT]-05Z [10pm PDT]. Clearing expected by late Thursday morning. ∨
KSFO BRIDGE APPROACH...PER COORD WITH OAKLAND CWSU THOUGHT IS THAT THE STRATUS WILL REACH THE APPROACH BY APPROX 04Z-05Z. CLEARING EXPECTED BY LATE THURSDAY MORNING. [AVI2]
Monterey Bay Area terminals… MVFR [Marginal Visual Flight Rules] ceilings developing between 00Z [5pm PDT]-04Z [9pm PDT] followed by MVFR [Marginal Visual Flight Rules] ceilings overnight. Clearing is likely by late morning Thursday. ∨
MONTEREY BAY AREA TERMINALS...MVFR CIGS DEVELOPING BETWEEN 00Z-04Z FOLLOWED BY MVFR CIGS OVERNIGHT. CLEARING IS LIKELY BY LATE MORNING THURSDAY. [AVI2]
Marine. As of 02:39pm PDT Wednesday… high pressure over the Central Coast will lead to light northwest winds and gentle seas this afternoon. Northwest winds are forecast to begin to increase tonight with the strongest winds along the Big Sur coastline through the remainder of the week. ∨
.MARINE...AS OF 02:39 PM PDT WEDNESDAY...HIGH PRESSURE OVER THE CENTRAL COAST WILL LEAD TO LIGHT NORTHWEST WINDS AND GENTLE SEAS THIS AFTERNOON. NORTHWEST WINDS ARE FORECAST TO BEGIN TO INCREASE TONIGHT WITH THE STRONGEST WINDS ALONG THE BIG SUR COASTLINE THROUGH THE REMAINDER OF THE WEEK. [AVIA]
.MTR WATCHES/WARNINGS/ADVISORIES... .TNGT...NONE. [WARN]
Public Forecast: Rgass; Aviation: Canepa; Marine: Sims ∨
PUBLIC FORECAST: RGASS AVIATION: CANEPA MARINE: SIMS [CRED]
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Tonight Patchy fog after 11pm. Otherwise, cloudy, with a low around 50°. WSW wind around 7 mph.
Thursday Patchy fog before 11am. Otherwise, cloudy, with a high near 59°. West wind 3 to 7 mph.
Thursday Night Patchy fog after 11pm. Otherwise, cloudy, with a low around 51°. WNW wind 6 to 8 mph.
Friday Patchy fog before 11am. Otherwise, cloudy, with a high near 60°. West wind around 6 mph.
Friday Night Mostly cloudy, with a low around 51°. West wind 9 to 14 mph.
Saturday Partly sunny, with a high near 61°.
Saturday Night Patchy fog after 11pm. Otherwise, mostly cloudy, with a low around 51°.
Sunday Patchy fog before 11am. Otherwise, mostly cloudy, with a high near 61°.
Sunday Night Mostly cloudy, with a low around 52°.
Monday Partly sunny, with a high near 61°.
Monday Night Mostly cloudy, with a low around 51°.
Tuesday Mostly sunny, with a high near 61°.
Tuesday Night Mostly cloudy, with a low around 51°.
Wednesday Partly sunny, with a high near 62°.
Patchy fog after 11pm. Otherwise, cloudy, with a low around 50. West southwest wind around 7 mph.
Patchy fog before 11am. Otherwise, cloudy, with a high near 59. West wind 3 to 7 mph.
Patchy fog after 11pm. Otherwise, cloudy, with a low around 51. West northwest wind 6 to 8 mph.
Patchy fog before 11am. Otherwise, cloudy, with a high near 60. West wind around 6 mph.
Mostly cloudy, with a low around 51. West wind 9 to 14 mph.
Partly sunny, with a high near 61.
Patchy fog after 11pm. Otherwise, mostly cloudy, with a low around 51.
Patchy fog before 11am. Otherwise, mostly cloudy, with a high near 61.
Mostly cloudy, with a low around 52.
Partly sunny, with a high near 61.
Mostly cloudy, with a low around 51.
Mostly sunny, with a high near 61.
Mostly cloudy, with a low around 51.
Partly sunny, with a high near 62.