Heat in California, July 1 to 30, 2003

Name: Heat in California, July 1 to 30, 2003
Start: 2003-07-01T15:00
End: 2003-07-30T06:00
Location: California

July 1 to 30, 2003 · NWS HNX · 4 events in 4 counties and zones

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: $2,000
Events: 4

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.

What happened

The episode as NWS HNX wrote it up.

A consistently hot July was noted in Interior Central California denoted by the average high temperature of 101F at Fresno CA. During the month in the Central San Joaquin Valley, Fresno recorded 22 days of 100F or above which ties the 3rd highest number set in 1891. Similar conditions were noted at Bakersfield in the Southern San Joaquin Valley, adjacent foothill locations, and in the Kern Deserts. Furthermore, a relatively consistent wind flow aloft from the southeast brought monsoonal moisture over the area several times during the month providing for high minimum temperatures and several records due to the above normal amount of moist air over the area. Bakersfield in the South Valley tied its overall high minimum temperature with an 86F on the 29th. Several daily rainfall records were set even though amounts may not have been high (the area is not known for having rainfall in the July time period). There were unquantifiable losses to various grape crops on the East Side of the San Joaquin Valley, especially the Flame variety, due to the extended period of time with high heat.

What forecasters said that day

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 Hanford, CA wrote its last area forecast discussion before the first event at Jul 1, 12:15 PM PST, 2 hours 45 minutes earlier.

Area forecast discussion, Jul 1, 12:15 PM PST, 2 hours 45 minutes before

INTERIOR CENTRAL CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HANFORD CA
115 PM PDT TUE JUL 1 2003

MID AFTERNOON WV IMAGERY SHOWS LOW PRESSURE SLIPPING INTO ALBERTA
FROM BRITISH COLUMBIA...WITH THE ASSOCIATED TROUGH EXTENDING
SOUTHWEST OFF THE CALIFORNIA COASTLINE. CLOSER TO HOME...THIS HAS
RESULTED IN A FAIRLY TIGHT ONSHORE GRADIENT...BUT THIS HAS
TRANSLATED INTO ONLY LOCALLY GUSTY WINDS IN THE FAVORED
CANYONS/PASSES AND DESERTS OF KERN COUNTY. OTHERWISE...SKIES HAVE
REMAINED CLOUD FREE ALL DAY WITH TEMPERATURES VIRTUALLY UNCHANGED
FROM 24 HOURS EARLIER.

THE LOW PRESSURE IS FORECAST TO WOBBLE EASTWARD ACROSS THE CANADIAN
PROVINCES WHILE BAGGY TROUGHINESS PERSISTS OFFSHORE. MODELS ARE
CONSISTENT IN PINCHING OFF THE SOUTHERN PORTION OF THIS TROUGH INTO
A WEAK CLOSED CIRCULATION...AND RETROGRADING THIS ENERGY FARTHER OUT
TO SEA. HIGH PRESSURE ACROSS THE FOUR CORNERS STATES WILL BUCKLE
NORTHWESTWARD INTO THE DISTRICT...HELPING TO ELIMINATE WHAT MINIMAL
MARINE INFILTRATION THE VALLEY HAS EXPERIENCED AS OF LATE. PER
ETA/GFS SOLUTIONS...H5 HEIGHTS SHOW ONLY SLIGHT GAINS THROUGH
FRIDAY...AS H85 TEMPERATURES SHOW ABOUT 1 DEGC WARMING EACH DAY
THROUGH THE END OF THE WORK WEEK. WILL ACCORDINGLY EXPERIENCE MODEST
TEMPERATURE RISES...WITH SLIGHTLY MORE PRONOUNCED WARMING IN THE
LOWER ELEVATIONS AS MARINE INFLUX COMES TO AN END.

IN THE EXTENDED PERIOD SATURDAY THRU TUESDAY...DRY SOUTHWEST FLOW IS
PROGGED BY MOST MEDIUM RANGE MODELS TO PREVAIL OVER THE FORECAST
AREA. THE RIDGE OF HIGH PRESSURE IS PROGGED TO WEAKEN BEGINNING
SATURDAY...AS THE MODELS TRY TO SHIFT AN EAST PACIFIC LOW PRESSURE
TROUGH TOWARDS THE PACIFIC NORTHWEST COAST. IF THIS SCENARIO PANS
OUT...SOME COOLING WILL OCCUR DUE TO BOTH SYNOPTIC AFFECTS AND
COASTAL INFLUENCE. MANUAL GUIDANCE FROM THE GFS SHOWS AROUND A 6
DEGREE COOLING AT MERCED FROM SATURDAY TO TUESDAY WHILE BAKERSFIELD
COOLS AROUND 8 DEGREES. IT WILL BE TRICKY TO GAUGE THE MAGNITUDE OF
THE MARINE INFLUENCE...HOWEVER WILL UNDERCUT GUIDANCE OVER THE NORTH
VALLEY.

.HNX...NONE.

BURGER/DUDLEY

Hazardous weather outlook, Jul 1, 4:30 AM PST, 10 hours 30 minutes before

CAZ089>099-021230-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HANFORD CA
530 AM PDT TUE JUL 1 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE CENTRAL CALIFORNIA
INTERIOR.

.DAY ONE...TODAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.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 TO THEIR LOCAL NATIONAL WEATHER SERVICE OFFICE.

Event by event

4 heat. Local standard time, as filed.

Heat, E Central S.J. Valley

When: July 1, 3:00 PM PST to July 30, 6:00 AM PST
Where: E Central S.J. Valley forecast zone
Crop damage: $1,000
Reported by: OFFICIAL NWS OBS.

Heat, Se S.J. Valley

When: July 1, 3:00 PM PST to July 30, 6:00 AM PST
Where: Se S.J. Valley forecast zone
Crop damage: $1,000
Reported by: OFFICIAL NWS OBS.

Heat, W Central S.J. Valley

When: July 1, 3:00 PM PST to July 30, 6:00 AM PST
Where: W Central S.J. Valley forecast zone
Reported by: AWOS,ASOS,MESONET,ETC

Heat, Sw S.J. Valley

When: July 1, 3:00 PM PST to July 30, 6:00 AM PST
Where: Sw S.J. Valley forecast zone
Reported by: AWOS,ASOS,MESONET,ETC

What these are

Heat: Heat below excessive heat criteria that still caused deaths, injuries or significant impacts.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in California in 2003 Every state in 2003 This day in weather history Warnings in California, July 2003

Sources

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: 5367128, 5367129, 5367130, 5367217.