676
FNUS76 KMTR 202157
FWSMTR
SPOT FORECAST FOR OES PREPO WEATHER...MCFD ECC
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
157 PM PST SAT DEC 20 2025
FORECAST IS BASED ON FORECAST START TIME OF 0000 PST ON DECEMBER 21.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE.
DISCUSSION
CORRECTION TO WIND GUSTS IN DISCUSSION. 25 MPH WAS A
TYPO, SHOULD READ 35 MPH. NO OTHER CHANGES. A FLOOD WATCH IS IN
EFFECT THROUGH 4 PM MONDAY. THE HEAVY RAIN WILL ARRIVE EARLY
SUNDAY AFTERNOON AND CONTINUE UNTIL MONDAY MORNING BEFORE THE
NORTH BAY GETS A BREAK. DURING THIS TIME, THIS LOCATION IS
EXPECTED TO RECEIVE 1-2 INCHES OF RAIN. LOCALIZED FLOODING IS
EXPECTED IN LOW- LYING URBAN AREAS AND SMALL STREAMS AND CREEKS.
SOME DEBRIS FLOWS ARE POSSIBLE, BUT WILL BECOME MORE LIKELY LATER
IN THE WEEK AS THE SOILS BECOME MORE SATURATED. WINDS WILL REMAIN
OUT OF THE SOUTH AND GRADUALLY RAMP UP THROUGH THE NIGHT FROM 10
MPH AROUND SUNSET TONIGHT TO 20 MPH WITH GUST TO 35 MPH BY
SUNRISE SUNDAY. WINDS WILL REMAIN NEAR THIS INTENSITY THROUGH THE
DAY SUNDAY BEFORE TAPERING OFF TO A MODERATE NORTHERLY BREEZE
EARLY MONDAY MORNING. MORE RAIN IS ON THE WAY THROUGHOUT THE WEEK,
WITH THE NEXT HEAVY BAND EXPECTED TO ARRIVE SOMETIME ON TUESDAY
AND CONTINUE INTO WEDNESDAY NIGHT. THE RAIN WILL BE SIMILAR BUT
WINDS WILL LIKELY BE STRONGER WITH THIS SECOND ROUND. MODERATE
RAIN AND GUSTY WINDS WILL LINGER INTO FRIDAY BEFORE THE WEATHER
FINALLY BREAKS THIS WEEKEND. ALL TOLD WE EXPECT AROUND 6-8 INCHES
OF RAIN THROUGH THE WEEK.
REST OF TONIGHT
SKY/WEATHER.........CLOUDY. RAIN.
MIN TEMPERATURE.....51-55.
MAX HUMIDITY........98-100 PERCENT.
SURFACE WINDS (MPH).SOUTH WINDS 13 TO 19 MPH WITH GUSTS TO AROUND
33 MPH.
CHANCE OF PCPN......90 PERCENT.
CHANCE OF THUNDER...5 PERCENT.
MIXING HEIGHT.......400 FT AGL.
TRANSPORT WINDS.....SOUTHWEST AROUND 24 MPH.
MARINE LAYER........NONE.
SUNRISE.............
SUNDAY
SKY/WEATHER.........CLOUDY. RAIN.
MAX TEMPERATURE.....54-58.
MIN HUMIDITY........97-100 PERCENT.
SURFACE WINDS (MPH).BREEZY. SOUTH WINDS 15 TO 21 MPH WITH GUSTS TO
AROUND 39 MPH.
CHANCE OF PCPN......100 PERCENT.
CHANCE OF THUNDER...14 PERCENT.
MIXING HEIGHT.......1900 FT AGL.
TRANSPORT WINDS.....SOUTH AROUND 29 MPH.
MARINE LAYER........NONE.
SUNSET..............
SUNDAY NIGHT
SKY/WEATHER.........CLOUDY. RAIN.
MIN TEMPERATURE.....48-52.
MAX HUMIDITY........98-100 PERCENT.
SURFACE WINDS (MPH).WEST WINDS 6 TO 19 MPH. GUSTS UP TO 32 MPH IN
THE EVENING.
CHANCE OF PCPN......100 PERCENT.
CHANCE OF THUNDER...5 PERCENT.
MIXING HEIGHT.......0 FT AGL.
TRANSPORT WINDS.....SOUTHWEST AROUND 15 MPH.
MARINE LAYER........NONE.
SUNRISE.............
MONDAY
SKY/WEATHER.........CLOUDY. RAIN LIKELY IN THE MORNING, THEN RAIN
IN THE AFTERNOON.
MAX TEMPERATURE.....52-56.
MIN HUMIDITY........86-90 PERCENT.
SURFACE WINDS (MPH).NORTHWEST WINDS UP TO 8 MPH.
CHANCE OF PCPN......80 PERCENT.
CHANCE OF THUNDER...1 PERCENT.
MIXING HEIGHT.......600 FT AGL.
TRANSPORT WINDS.....NORTHWEST AROUND 7 MPH.
MARINE LAYER........NONE.
SUNSET..............
FORECASTER...D_FLYNN
REQUESTED BY...JONATHAN RICHARDSON
TYPE OF REQUEST...OTHER
.TAG 2527983.0/MTR
.DELDT 12/20/25
.FORMATTERVERSION 2.0.0
.EMAIL ECCDUTYOFFICER@MARINCOUNTY.GOV
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