, Issued at 247 AM PST Wed Jan 7 2026 (Today and tonight)
Flooding continues for areas near and downstream of Mark West Creek near Mirabel Heights as indicated by gauges and cameras. A Flood Warning is in effect until 8 AM - this will likely be replaced by a long duration Flood Advisory then as that is when it is forecast to recede into minor flood stage. Residual troughiness will allow for a dying cold front to skirt the region today. High clouds from this feature will continue to stream into the region which will help limit the extent of fog and stratus this morning. Sensible weather wise, expect near normal temperatures and more gloomy conditions.
..issued at 247 AM PST Wed Jan 7 2026 (Thursday through Tuesday)
Global ensemble clusters are in agreement of some form of longwave upper-level ridging dominating our long term forecast and beyond. This will yield fair daytime conditions with cold overnight conditions. An Extreme Cold Watch has been issued for most of the area from 1 AM Friday to 9 AM Friday to cover the Thursday night period. It's a bit of a nuanced forecast though as it isn't a cold air mass bringing this along. In fact, 850 millibar temperatures are forecast to warm near 7 degrees Celsius which is near the daily mean. Some meteorological rule of thumb equates this to 45 degrees at 5,000 feet. To figure out what's going on, we need to zoom out. It is winter which means nights are long and therefore there is a lot of time for radiational cooling to occur. As the Earth cools, a shallow, stable layer develops near the surface, this is known as a temperature inversion. Quantitatively, this is when temperature increases with height, like in this case where we have ~0 degrees Celsius at the surface and ~7 degrees Celsius at 5,000 feet. You can think of it as a "cold lid". We are going to put a pin in this for now. At the surface, high pressure will nose into the California/Oregon border before ultimately building into the Great Basin. Along the California Coast, a coastal trough will develop which will facilitate offshore flow. Normally this would be a fire weather concern, but we are way past that. We are going to keep our fire weather thinking caps on though to understand why it is going to be cold in some spots and not others. Circling back to our "cold lid", offshore flow aloft will not be strong or turbulent enough to break its seal. Some locations downslope of/in the higher terrain are not in the Extreme Cold Watch as sufficient mixing will keep them relatively warmer. The coldest spots will be Interior Monterey and San Benito Counties, where below freezing temperatures are possible. The North Bay Coast and San Francisco Peninsula Coast will be moderated by the Pacific Ocean and downslope flow coming off of the adjacent terrain. The Friday night period will be cold, but not quite as cold as Thursday night. Overnight temperatures will slowly rise through the weekend to become above criteria by the start of next week.
(18z TAFS) Issued at 943 AM PST Wed Jan 7 2026
VFR is expected to prevail through the forecast period for all terminals. There is a slight chance (primarily South Bay and Monterey Bay terminals) for MVFR cigs to develop later tonight into early Thursday morning, as a relatively weak cold front pushes through our area. Winds will increase along and behind the front becoming gusty at times from the W/NW.
Vicinity of SFO, VFR conditions are expected to prevail through the forecast period with gusty onshore winds settling in this evening and persisting through a majority of the remaining TAF period as a cold front passes south through our area.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, VFR is expected to prevail through a majority of the TAF period with a chance for MVFR cigs late into the overnight through mid-Thursday morning. Winds will increase and become gusty later this evening and continue through the overnight as a cold front pushes through our area.
(today through Monday) Issued at 943 AM PST Wed Jan 7 2026
Northerly winds settle in behind a series of weak fronts today, gradually increasing through the afternoon and overnight. Along with the increasing northerly winds will be a building moderate northwest swell on Thursday, combining o create hazardous conditions on the water through late Thursday night, with winds easing and wave energy decreasing into the weekend.
Ca, High Surf Advisory from 1 AM Thursday to 10 PM PST Friday for CAZ006-505-509-530.
Extreme Cold Watch from late Thursday night through Friday morning for CAZ502-506-508-510-512>518-528>530.
Beach Hazards Statement from late tonight through Friday evening for CAZ529.
PZ, Small Craft Advisory from 3 PM this afternoon to 3 PM PST Thursday for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 9 PM PST Thursday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.
