California, 2003

Heavy Rain and Strong Wind in California, April 21, 2003

April 21, 2003 · NWS HNX · 4 events in 4 counties and zones

Locally heavy rain accompanied by strong wind and small hail occurred in the Central and Southern San Joaquin Valley during the late afternoon hours of the 21st. Hail size was less than 1/2-inch but, in conjunction with, locally heavy rain led to local highway problems just northwest of Merced on State Highway 99.

Where it happened

Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

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The toll

Deaths
0
Injuries
0
Property damage
$15,000
Crop damage
None recorded
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.

Locally heavy rain accompanied by strong wind and small hail occurred in the Central and Southern San Joaquin Valley during the late afternoon hours of the 21st. Hail size was less than 1/2-inch but, in conjunction with, locally heavy rain led to local highway problems just northwest of Merced on State Highway 99. Snow level in the adjacent Southern Sierra Nevada dropped to 3500 feet mean sea level. Gusty wind late in the afternoon around Fresno resulted in some downed power lines and loss of power to 771 utility customers in North-Central Fresno. Unofficial rainfall amounts from convective showers were as high as 0.63" in Northeast Fresno with reports of pea-size hail and lightning. Official rain totals for the day were 0.20" at Fresno, 0.15" at Madera, and 0.13" at Visalia. In the Tehachapi Mountains at Bear Valley over 1.00 inch of rain fell due to the showers on the 21st.

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 Apr 21, 1:00 PM PST, 2 hours earlier.

Area forecast discussion, Apr 21, 1:00 PM PST, 2 hours before
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Hazardous weather outlook, Apr 21, 6:08 AM PST, 8 hours 52 minutes before
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In the hours before

Special weather statement, Apr 21, 9:30 AM PST, 5 hours 30 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

3 heavy rain, 1 strong wind. Local standard time, as filed.

Heavy Rain, Kern

When
April 21, 3:00 PM PST to 5:00 PM PST
Where
Kern County, 11 mi W of Tehachapi
Property damage
$1,000
Reported by
GOVT OFFICIAL
Coordinates
35.343, -118.730 (the zone’s center; the record gives no point)

Heavy Rain, Merced

When
April 21, 3:30 PM PST to 4:00 PM PST
Where
Merced County, 3 mi NW of Merced
Property damage
$8,000
Reported by
NEWSPAPER
Coordinates
37.192, -120.718 (the zone’s center; the record gives no point)

Strong Wind, E Central S.J. Valley

When
April 21, 4:00 PM PST to 4:30 PM PST
Where
E Central S.J. Valley forecast zone
Measured
29 kt (33 mph) estimated gust
Property damage
$5,000
Reported by
NEWSPAPER

Heavy Rain, Kings

When
April 21, 5:00 PM PST to 5:30 PM PST
Where
Kings County, Hanford
Property damage
$1,000
Reported by
NEWSPAPER
Coordinates
36.075, -119.815 (the zone’s center; the record gives no point)

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.
Strong Wind
Non-thunderstorm winds below high wind criteria that nonetheless caused damage or casualties.

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

The same day elsewhere

More

Every storm in California in 2003Every state in 2003This day in weather historyWarnings in California, April 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 2026-10-01. Each event’s entry at NCEI: 5350589, 5350588, 5350587, 5350586.