Strong winds caused power outages and damage to power lines across San Mateo County as tree limbs crashed into them.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MTR wrote it up.
Strong winds caused power outages and damage to power lines across San Mateo County as tree limbs crashed into them.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS San Francisco Bay Area, CA wrote its last area forecast discussion before the first event at Sep 29, 1:00 PM PST, 1 hour earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA ISSUED BY NATIONAL WEATHER SERVICE EUREKA CA AVIATION DISCUSSION ISSUED BY NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD 200 PM PDT TUE SEP 29 2009 .DISCUSSION...AS OF 2:00 PM PDT...A FAIRLY VIGOROUS COLD FRONT PUSHED ACROSS THE BAY AREA EARLIER TODAY AND IS NOW HEADED EAST INTO THE CENTRAL VALLEY. WHILE LITTLE PRECIPITATION WAS ASSOCIATED WITH THIS FEATURE...EVIDENCE OF ITS PASSAGE COULD BE FELT WITH THE GUSTY WINDS. TEMPERATURES AT MID AFTERNOON WERE A MIXED BAG...WITH MANY SPOTS NEAR THE COAST AND IN THE NORTH BAY AT OR SLIGHTLY AHEAD OF READINGS FROM 24 HOURS EARLIER WHILE HIGH ELEVATION SITES SHOWED STRONG COOLING. FOR EXAMPLE...TEMPERATURES AT SANTA RITA PEAK AND MOUNT TAM ARE DOWN SOME 20 TO 25 DEGREES COMPARED TO YESTERDAY'S OBSERVATIONS. COLD AIR WILL CONTINUE TO FILTER INTO THE FORECAST AREA OVERNIGHT...WITH READINGS DIPPING INTO THE 40S AT MANY SITES AWAY FROM THE IMMEDIATE COAST AND BAYS. THE COLDEST SPOTS WILL BOTTOM OUT IN THE LOWER TO MID 40S...AND INCLUDE THE SOUTHERN SALINAS VALLEY AND PORTIONS OF THE NORTH BAY AS WELL AS HIGHER ELEVATION LOCALES. THE PATTERN TRANSITIONS BEGINNING TOMORROW AS HIGH PRESSURE BUILDS OFFSHORE BRINGING A WARMING TREND TO THE REGION. DESPITE THE COLD MORNING...TEMPERATURES WILL RECOVER NICELY AS THE FLOW ALOFT TRENDS NORTHERLY WITH WIDESPREAD 70S FOR INLAND AREAS. THE GOING FORECAST MAY END UP BEING A LITTLE TOO COOL FOR SITES THAT TYPICALLY BENEFIT IN THIS REGIME...SUCH AS SANTA ROSA...BUT WE WOULDN'T BE SURPRISED TO SEE A FEW LOWER 80S TOMORROW IN THE WARMEST SPOTS. THE MARINE LAYER WILL BE A NO SHOW FOR AWHILE AS THE BOUNDARY LAYER REMAINS QUITE DRY AND WELL MIXED. FURTHER WARMING IS EXPECTED FOR THURSDAY BUT A SERIES OF SHORTWAVES TRACKING ACROSS THE PACIFIC NORTHWEST WILL KEEP READINGS IN CHECK. IN FACT...THE LONGER RANGE PROGS SUGGEST THAT A FAIRLY DEEP TROUGH WILL BE CARVED OUT ACROSS THE GREAT BASIN OVER THE WEEKEND WHICH TRANSLATES LOCALLY TO A RETURN OF COOLER AND LOCALLY BREEZY WEATHER. && .AVIATION...AS OF 11:15 AM PDT TUESDAY...DUE TO THE EARLIER PASSAGE OF A COLD FRONT...THE MARINE LAYER HAS CLEARED OUT OF THE REGION. WOULD EXPECT WIDESPREAD VFR CONDITIONS INTO WEDNESDAY. THE MAIN CONCERN FOR THIS AFTERNOON INTO EARLY THIS EVENING WILL BE GUSTY NORTHWEST WINDS. VICINITY OF KSFO...VFR CONDITIONS THROUGH THE PD. WEST AND NORTHWEST WINDS OF 20 TO 30 KT WITH GUSTS TO 35 KT. ISSUED AIRPORT WEATHER WARNING FROM NOW UNTIL 03Z TONIGHT. KSFO BRIDGE APPROACH...SAME AS SFO. MONTEREY BAY TERMINALS...VFR CONDITIONS. WINDS WILL INCREASE TODAY TO 15 TO 20 KT WITH AFTERNOON GUSTS AROUND 25 KT. && .MARINE...GALE FORCE GUSTS BEHIND A COLD FRONT WILL DIMINISH OVERNIGHT. WAVES IN ASSOCIATION WITH THE STRONG WINDS WILL SLOWLY SUBSIDE ON WEDNESDAY. HIGH PRESSURE RETURNS TO THE E PAC BEGINNING WED WITH A DEVELOPING THERMAL TROUGH ALONG THE COAST. NORTH WINDS WILL REMAIN STRONGEST AND SEAS HIGHEST BEYOND 10NM FROM SHORE THROUGH THE WEEKEND. JCA && .FIRE WEATHER...FRONTAL PASSAGE TODAY HAS RESULTED IN INCREASED WINDS ALONG WITH HIGHER HUMIDITIES. GOOD TO EXCELLENT HUMIDITY RECOVERIES ARE EXPECTED OVERNIGHT FOR ALL AREAS. THE UPPER FLOW SHIFTS TO THE NORTH-NORTHEAST LATE WEDNESDAY WITH A DRYING TREND NOTED. A FIRE WEATHER WATCH HAS BEEN POSTED FOR PORTIONS OF THE NORTH AND SOUTH BAY ZONES BEGINNING WEDNESDAY EVENING AND CONTINUING INTO THE AFTERNOON THURSDAY FOR THE COMBINATION OF LOW RH AND WINDS. AT THE PRESENT TIME THIS LOOKS LIKE A LOW-END EVENT HOWEVER WITH HUMIDITY RECOVERIES ONLY AROUND 30% AND SUSTAINED RIDGE WINDS IN THE 10-20 MPH RANGE WITH LOCALLY HIGHER GUSTS IT APPEARS TO BE JUSTIFIED. ALSO...THE SCOPE AND DURATION WILL BE LIMITED AS WINDS DIMINISH DURING THE AFTERNOON HOURS ON THURSDAY. && .MTR WATCHES/WARNINGS/ADVISORIES... AIRPORT WEATHER WARNING FOR WINDS FOR SFO AIRPORT UNTIL 8 PM PDT. FIRE WEATHER WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON FOR NORTH BAY CAZ507 AND SOUTH BAY CAZ511. SMALL CRAFT ADVISORY ALL COASTAL WATERS AND BAYS. PUBLIC FORECAST: BURGER/EKA AVIATION: SWEET/LOX MARINE: JCA/EKA FIRE WEATHER: BURGER/EKA NWS ON THE WEB AT WEATHER.GOV/SANFRANCISCO
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA 217 PM PDT TUE SEP 29 2009 CAZ006-505-506-508-510-512-513-516>518-528>530-302130- SAN FRANCISCO- COASTAL NORTH BAY...INCLUDING POINT REYES NATIONAL SEASHORE- NORTH BAY INTERIOR VALLEYS-SAN FRANCISCO BAY SHORELINE- EAST BAY INTERIOR VALLEYS-SANTA CRUZ MOUNTAINS- SANTA CLARA VALLEY...INCLUDING SAN JOSE- SOUTHERN SALINAS VALLEY...ARROYO SECO...AND LAKE SAN ANTONIO- SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST- MOUNTAINS OF SAN BENITO AND INTERIOR MONTEREY COUNTY INCLUDING PINNACLES NATIONAL MONUMENT- NORTHERN SALINAS VALLEY...HOLLISTER VALLEY...AND CARMEL VALLEY- NORTHERN MONTEREY BAY-SOUTHERN MONTEREY BAY AND BIG SUR COAST- 217 PM PDT TUE SEP 29 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SAN FRANCISCO BAY AREA AND MONTEREY BAY AREA. .DAY ONE...THIS AFTERNOON AND TONIGHT STRONG WEST TO NORTHWEST WINDS OF 20 TO 30 MPH WITH LOCAL GUSTS TO 40 MPH WILL CONTINUE INTO THIS EVENING BEHIND A COLD FRONT. BEHIND THIS FRONT...TEMPERATURES WILL DROP INTO THE 40S ACROSS INLAND AREAS TONIGHT. THE COLDEST READINGS WILL OCCUR IN THE VALLEYS OF SONOMA AND NAPA COUNTIES. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS PER STANDARD OPERATING PROCEDURES. CAZ507-511-302130- NORTH BAY MOUNTAINS-EAST BAY HILLS AND DIABLO RANGE- 217 PM PDT TUE SEP 29 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SAN FRANCISCO BAY AREA AND MONTEREY BAY AREA. .DAY ONE...THIS AFTERNOON AND TONIGHT STRONG WEST TO NORTHWEST WINDS OF 20 TO 30 MPH WITH LOCAL GUSTS TO 40 MPH WILL CONTINUE INTO THIS EVENING BEHIND A COLD FRONT. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY A FIRE WEATHER WATCH IS IN EFFECT FOR THE EAST AND NORTH BAY HILLS FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON. REFER TO SFORFWMTR FOR ADDITIONAL INFORMATION. OFFSHORE FLOW WILL PROVIDE WARMER AND WINDY CONDITIONS WHICH MAY LEAD TO CRITICAL FIRE WEATHER CONDITIONS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS PER STANDARD OPERATING PROCEDURES.
The national radar mosaic for the moment the first event began.
2 strong wind. Local standard time, as filed.
Roughly 270 customers lost power in Pescadero as strong and gusty winds blew tree limbs onto power lines.
Roughly 23 customers lost power in East Palo Alto and Woodside as strong and gusty winds blew tree limbs onto power lines.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2009Every state in 2009This day in weather historyWarnings in California, September 2009
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 198209, 198210.