Byron, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

911
FXUS66 KMTR 070332
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
832 PM PDT Sun Apr 6 2025

...New MARINE...

.SYNOPSIS...
Issued at 1214 PM PDT Sun Apr 6 2025

Light rain this evening, hazardous beach conditions through
Monday, and warm and dry conditions the rest of the week.

&&

.UPDATE...
Issued at 438 PM PDT Sun Apr 6 2025

The weak cold front is currently located in far northern
California with steady prefrontal rain north of Eureka area. As
this boundary slides south, the tail end will bring overcast skies
to the Bay Area and light prefrontal precipitation mainly to the
North Bay and less so to the Peninsula overnight into Monday
morning. The forecast confidence is fairly high that the bulk of
the rain will be done by sunrise, and wont reach much further
south than San Jose. This front is pretty weak, and the cold air
behind it will not be enough to trigger much instability. In fact
the 850-700 lapse rate is will be a pathetic 2 C/km and the 500
mb temperature will actually remain higher than normal (-14C vs
-17C). With these stats, we`ll be lucky to even get fair weather
 cumulus clouds in the afternoon. In other words, there is no
 threat of thunderstorms tomorrow. The temperature will be a
 couple degrees cooler than today however, mainly due to the
 increased cloud cover.

&&

.SHORT TERM...
(This evening through Monday)
Issued at 1214 PM PDT Sun Apr 6 2025

KMUX has been switched over to precipitation mode as rain begins to
drift into our northernmost marine zone as the responsible weak cold
front continues to slowly trek towards the West Coast. As a result,
expect an increase in high cloud cover throughout the day. Sensible
weather will likely feel cooler than yesterday due to an increase in
wind and the clouds preventing the sun from feeling as intense.
Light rain can be expected in the North Bay this evening and
overnight with totals up to a quarter of an inch. Sites south of the
Golden Gate Bridge may be able to collect a few hundredths with the
help of orographic lift. Of greatest importance over the next 36
hours is the Beach Hazards Statement in effect for all Pacific
Coast beaches.

&&

.LONG TERM...
(Monday night through next Saturday)
Issued at 1214 PM PDT Sun Apr 6 2025

Monday will have the (relatively) coldest conditions of the week as
cold air funnels in behind the cold front, but the warming trend
will quickly resume Tuesday as heights rise and surface high
pressure builds across the West. Wednesday will be the warmest day
of the week thanks to the longwave ridge axis that will be
centered over our region. Thursday will begin the gradual cooling
trend with a dry, weak cold front slated to sweep across the
region on Friday. For context, we have had warmer days this year
and no records are expected to be broken, that`s not the most
important thing though. HeatRisk is. Minor HeatRisk will be
present every day with Wednesday through Friday showing the most
widespread impacts for coastal and interior areas of the Bay Area
and Central Coast.

NWS Minor HeatRisk:

- Heat of this type is tolerated by most; however there is a minor risk
  for extremely heat-sensitive groups to experience negative
  heat- related health effects.

- The risk is primarily for those who are extremely sensitive to heat,
  especially when outdoors without effective cooling and/or
  adequate hydration.

- Very common heat.

- For those at risk, actions that can be taken: increase
  hydration, reduce time spent outdoors or stay in the shade when
  the sun is strongest, and open windows at night and use fans to
  bring cooler air inside buildings.

&&

.AVIATION...
(00Z TAFS)
Issued at 438 PM PDT Sun Apr 6 2025

Widespread VFR conditions will persist this afternoon, but high
clouds signal a change in the pattern. A weak cold front is
currently moving through far northern California and will slide
across the Bay Area overnight into Monday morning. This front will
bring widespread MVFR-IFR ceilings to the Bay Area and Central
Coast, as well as some light rain to the North Bay and possibly SF
Peninsula early Monday morning. Winds will also shift to southerly
as the front approaches, before switching back to NW after FROPA.

Vicinity of SFO...While there is a small chance of light rain
reaching the terminal early Monday morning, I decided to omit it
from the TAF in order to focus on the timing of the ceiling drop
and wind shift. There is a 75% chance of ceilings dropping below
3,000 feet and remaining there for several hours. On the other
hand, there is only a 25% chance of them dropping below 1,000
feet. Conditions will improve through the morning hours as the
winds return to a NW direction and the ceiling gradually lifts
and breaks up.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals...High confidence ceilings at MRY and SNS
will will drop to MVFR overnight, with a moderate confidence MRY
will drop to IFR. There is virtually no chance for any rain to
make it this far south and the ceilings will lift through the late
morning.

&&

.MARINE...
(Tonight through next Saturday)
Issued at 832 PM PDT Sun Apr 6 2025

Buoys are reporting a moderate height, long period swell from the
WNW has reached the coastal waters. Winds will remain gentle to
moderate while shifting from SW to NW as a weak cold front moves
through Monday morning. The long period swell will gradually
abate through mid-week before stronger NW winds arrive next
weekend.

&&

.BEACHES...
Issued at 418 AM PDT Sun Apr 5 2025

A Beach Hazard Statement remains in effect for the entire
coastline. A long period swell is forecast to reach the coast
this morning. Forerunners of 18-20 sec arrive close to sunrise.
Swell periods are forecast to diminish through the day to Monday,
but swell heights will gradually increase. Therefore, initially
sneaker waves will be the main threat before switching to larger
shore break and rip currents. Beachgoers should be mindful Sunday
and Monday given potential hazards. Beachgoers should stay off of
jetties and rocks, keep pets on a leash, wear a life jacket, and
never turn your back on the ocean!

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Monday evening for CAZ006-505-
     509-529-530.

PZ...Small Craft Advisory until 9 AM PDT Monday for Pigeon Pt to Pt
     Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 3 AM PDT Tuesday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...Sarment
LONG TERM....Sarment
AVIATION...Flynn
MARINE...Flynn

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