Area forecast discussion National Weather Service San Francisco Bay area 827 PM PDT Wednesday Jun 19 2013 Discussion...as of 8:30 PM PDT Wednesday...upper level low is now centered over northern Idaho. The trough axis moved through the district last night and temperatures warmed up behind the trough. Temperatures today were about 5 degrees warmer than yesterday. The marine layer has mixed out allowing for a mostly sunny day today. Latest Oak sounding and feet Ord profiler show no signs of a marine inversion so stratus will be patchy in nature tonight with lots of sunshine expected Thursday. An upper level ridge will build off the California coast Thursday bringing warmer temperatures to the area through Saturday. The upper low will be very slow in its eastward movement and the onshore northwest flow will persist. As a result warming will be gradual and not very pronounced with highs reaching the lower 90s in the warmest inland valley locations on Friday and middle 90s on Saturday. The ridge will break down Sunday as an upper level low approaches the Pacific northwest resulting in cooler temperatures. Latest European model (ecmwf) brings the system in faster and has light precipitation spreading as far south as the sfo Bay area Sunday while the GFS is slower and keeps precipitation further north. Latest forecast indicates a slight chance of rain down to the sfo Bay area Sunday night into Monday morning. Large upper level high is still forecast to build over The Four- Corners area the middle of next week possibly bringing good warming to the inland areas. Summer begins at 05:04z on June 21st...or 10:04 PM PDT June 20th. && Aviation...as of 5:25 PM PDT Wednesday...VFR conditions expected through the forecast period. Gusty winds will continue through this evening then gradually ease overnight. Vicinity of ksfo...VFR conditions expected through the forecast period. Moderate to strong west winds this afternoon...with gusts over 30 knots anticipated. Ksfo bridge approach...similar to ksfo. Monterey Bay area terminals...VFR conditions expected through the forecast period. Moderate onshore winds this afternoon and evening. && Mtr watches/warnings/advisories... ... Arena to pt Reyes 0-10 nm Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm Small Craft Advisory...Pigeon pt to pt Piedras Blancas 10-60 nm Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm from 3 am glw...pt pinos to pt Piedras Blancas 0-10 nm until 3 am Small Craft Advisory...sf Bay until 9 PM Small Craft Advisory...mry Bay until 9 PM && $$ Public forecast: west pi aviation/marine: CW Visit US at www.Weather.Gov/sanfrancisco Follow US on facebook, twitter, and youtube at: www.Facebook.Com/US.Nationalweatherservice.Sanfranciscobayarea.Gov www.Twitter.Com/nwsbayarea www.Youtube.Com/nwsbayarea