High pressure, clear skies, and low humidities led to colder than normal low temperatures across the Sacramento Valley.
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 STO wrote it up.
High pressure, clear skies, and low humidities led to colder than normal low temperatures across the Sacramento Valley.
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 Sacramento, CA wrote its last area forecast discussion before the first event at Apr 17, 9:00 PM PST, 3 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SACRAMENTO CA 1000 PM PDT TUE APR 17 2007 .DISCUSSION... REVIEW OF SATELLITE IMAGERY TODAY INDICATED AIR MASS BECAME VERY UNSTABLE ONCE THE COLD AIR WORKED ITS WAY INTO NORCAL WELL BEHIND THE SURFACE COLD FRONT. CONVECTION ALSO WAS FURTHER S IN OUR CWA DUE TO A MORE SLY TRACK OF THE VORT MAX. UPPER LEVEL DIVERGENCE FROM UPPER JET STREAK ALSO ENHANCED VERTICAL MOTION OVER THE WEST SLOPES WHERE ECHOES FORMED CLUSTERS/LINES OF THUNDERSTORMS AT TIMES THIS AFTERNOON. LOW WBZS RESULTED IN SEVERAL SLEET/SMALL HAIL REPORTS IN THE SIERNEV FOOTHILLS. WATER VAPOR IMAGERY SHOWS VORT MAX CONTINUING TO DIG INTO THE NRN SAN JOAQUIN VLY AND CARVING OUT A DEEPER TROF OVER NORCAL THAN EARLIER FORECAST. THIS WILL ALLOW A 2NDARY SHORT WAVE VCNTY OF THE N COAST TO SLIDE FURTHER SWD ON THE BACKSIDE OF THE TROF AXIS OVERNITE. IR IMAGERY INDICATES CUMULIFORM CLOUDINESS WITH THIS FEATURE INDICATIVE OF INSTABILITY THAT WILL AFFECT THE COASTAL RANGE AND NRN MTNS OVERNITE. OTHERWISE SHOWERS EXPECTED TO DECREASE OVER W SLOPES OF SIERNEV AS VORT MAX MOVES INTO NV BY 12Z WED. LOCALLY STRONG WIND GUSTS EXPECTED TO CONTINUE OVER COASTAL RANGE UNTIL MIDNIGHT...THEN PRESSURE GRADIENTS ARE FORECAST TO RELAX. STRONG SUBSIDENCE IN THE WAKE OF THE VORT MAX NOW MOVING INTO THE SAN JQN VLY HAS CLEARED OUT WRN PORTIONS OF THE VLY. SHORT WAVE RIDGING EXPECTED TO GIVE NORCAL A DRY DAY ON WED WITH LIGHTER WINDS. ONSHORE FLOW IS EXPECTED DUE TO THE SURFACE HIGH OFF THE CA COAST. HOWEVER...NWLY FLOW ALOFT SHOULD MIX DOWN WITH SURFACE HEATING/WARMING DURING THE DAY. HOWEVER...WINDS ALOFT WILL BE LIGHTER BELOW THE SUBSIDENCE INVERSION WHICH IS FORECAST TO FORM AROUND 15 THOUSAND FEET. DEEPER LOW IS FORECAST TO BRING MORE CHILLY AND UNSETTLED WX TO NORCAL BY THU NITE/FRI. INITIAL SHORT WAVE MAY MOVE INTO NORCAL THU AROUND 18Z. OTHERWISE...GFS MODEL DIGS THIS SYSTEM WELL INTO SOCAL...AND IF THAT IS CASE...BEST INSTABILITY WILL BE S OF OUR FORECAST AREA. ALSO IN THIS CASE...STORMS WILL MOVE/PROPAGATE NWWD IN OUR CWA ON FRI. ANOTHER UPPER LOW FORECAST TO BRING MORE UNSETTLED WX TO NORCAL ON SUN. JHM && .AVIATION... UPPER LEVEL TROF OVER NORCAL WILL CONTINUE TO GIVE SCATTERED SHOWERS TO NORCAL OVERNITE...MAINLY OVER THE HIGHER TERRAIN. VFR CONDITIONS EXPECTED IN CENTRAL VLY AND FOOTHILLS WITH MVFR CIGS IN SHOWERS OVER HIGHER TERRAIN AND LOCAL IFR CONDITIONS OVER SIERNEV. LOCALLY BREEZY CONDITIONS WITH GUSTS 35-40 KTS OVER COASTAL RANGE EXPECTED TO DECREASE AFT 07Z. UPPER TROF TO MOVE E INTO NV ON WED WITH DRIER W-NWLY FLOW OVER NORCAL. VFR CONDITIONS EXPECTED. && .STO WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL MIDNIGHT PDT TONIGHT FOR CLEAR LAKE/SOUTHERN LAKE COUNTY-MOUNTAINS SOUTHWESTERN SHASTA COUNTY TO NORTHERN LAKE COUNTY. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SACRAMENTO CA 500 AM PDT TUE APR 17 2007 CAZ013>019-063-064-066>069-171400- SHASTA LAKE AREA/NORTHERN SHASTA COUNTY- BURNEY BASIN/EASTERN SHASTA COUNTY-NORTHERN SACRAMENTO VALLEY- CENTRAL SACRAMENTO VALLEY-SOUTHERN SACRAMENTO VALLEY- CARQUINEZ STRAIT AND DELTA-NORTHERN SAN JOAQUIN VALLEY- MOUNTAINS SOUTHWESTERN SHASTA TO NORTHERN LAKE COUNTIES- CLEAR LAKE/SOUTHERN LAKE COUNTY-MOTHERLODE- EAST FOOTHILLS/NORTH SACRAMENTO VALLEY- WESTERN PLUMAS COUNTY/LASSEN PARK-WEST SLOPE NORTHERN SIERRA NEVADA- 500 AM PDT TUE APR 17 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR INTERIOR NORTHERN CALIFORNIA. .DAY ONE...TODAY A LOW PRESSURE SYSTEM WITH COLD FRONT WILL DROP DOWN FROM THE PACIFIC NORTHWEST BRINGING COOLER WEATHER AND A CHANCE OF SHOWERS FOR THE NORTHERN MOUNTAINS AND NORTHERN SACRAMENTO VALLEY. GUSTY WINDS WILL ACCOMPANY THIS SYSTEM. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN... WEDNESDAY THROUGH MONDAY A MORE VIGOROUS LOW PRESSURE SYSTEM WITH A COLD FRONT WILL DROP DOWN FROM THE PACIFIC NORTHWEST WITH PRECIPITATION LIKELY FOR MUCH OF THE REGION THURSDAY AND FRIDAY. SNOW LEVELS WILL LIKELY DROP TO 3000 TO 4000 FEET. MODERATE SNOW ACCUMULATIONS COULD OCCUR ABOVE 5500 FEET IN THE SIERRA OVERNIGHT THURSDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. THE LATEST WEATHER INFORMATION IS AVAILABLE ON THE INTERNET AT (LOWER CASE): HTTP://WWW.WRH.NOAA.GOV/STO JCLAPP
2 cold/wind chill. Local standard time, as filed.
A daily low temperature record of 31 degrees was tied in Redding. The record was initially set in 1996.
A daily low temperature record of 36 degrees was set at the Sacramento Executive Airport. This broke the previous record of 37 degrees set in 2002.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2007Every state in 2007This day in weather historyWarnings in California, April 2007
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: 17534, 17536.