California, 2006

Damaging Wind in California, July 20, 2006

July 20, 2006 · NWS HNX · 1 event in 1 county or zone

A thunderstorm pushed through the southwest portion of Yosemite National Park in the afternoon of the 20th. High wind felled trees that knocked out power at El Portal due to a tree over a power line at 1600 PDT.

Where it happened

Every event with a place to put it. 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
$20,000
Crop damage
None recorded
Events
1

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 thunderstorm pushed through the southwest portion of Yosemite National Park in the afternoon of the 20th. High wind felled trees that knocked out power at El Portal due to a tree over a power line at 1600 PDT. Trees were subsequently downed across the Wawona Highway about 10 miles north of the Park's South Entrance by 1630 PDT.

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 20, 2:00 PM PST, 1 hour earlier.

Area forecast discussion, Jul 20, 2:00 PM PST, 1 hour before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
300 PM PDT THU JUL 20 2006

.SHORT TERM...LOOKING EAST IT IS QUITE OBVIOUS CONVECTION IS VERY
ACTIVE OVER THE SIERRA NEVADA THIS AFTERNOON. SCATTERED SHOWERS
AND THUNDERSTORMS HAVE ERUPTED OVER THE HIGH COUNTRY WITH NUMEROUS
LIGHTNING STRIKES MAINLY OVER THE FRESNO AND TULARE COUNTY PORTIONS.
STRONGEST ACTIVITY IS CURRENTLY LOCATED EAST OF PORTERVILLE AND HAS
SHOWN A GRADUAL WESTWARD TREND. APPEARS THIS IS GOING TO REACH THE
FOOTHILLS AND THUS HAVE ADDED ISOLATED EVENING THUNDERSTORMS.
ELSEWHERE...MORE ISOLATED CONVECTION IS OCCURRING OVER THE KERN
MOUNTAINS AND DESERTS. THOUGH STORMS ARE MOVING SLOWLY...NONE HAVE
REMAINED OVER THE SAME AREAS FOR VERY LONG AND NO FLASH FLOODING
CONCERNS AS OF YET. BUT THIS WILL BEAR WATCHING THROUGH THE EVENING.
THE PATTERN RESPONSIBLE FOR THE THUNDERSTORMS OUTBREAK WILL REMAIN
IN PLACE FRIDAY. MONSOON MOISTURE WILL CONTINUE TO SURGE INTO THE
DISTRICT WITH THE SOUTHEAST FLOW ALOFT. HOWEVER...THE CENTER OF THE
UPPER HIGH WILL BEGIN TO SET UP FARTHER WEST OVER THE GREAT BASIN.
RESULTS WILL BE A LESS FAVORABLE UPPER FLOW PATTERN FOR MOISTURE
ADVECTION AS WELL AS INCREASED SUBSIDENCE. THEREFORE...THINK
AFTN/EVE CONVECTION WILL DECREASE THROUGH THE WEEKEND AND BECOME
MAINLY ISOLATED BY SUNDAY.

THE OTHER CONCERN IS REGARDING THE HEAT. WHILE WE HAVE BEEN
EXPERIENCING WELL ABOVE NORMAL TEMPERATURES FOR MANY DAYS
NOW...THINGS ARE ABOUT TO GET EVEN WORSE. MODELS PROG THE UPPER
HIGH CENTER TO STRENGTHEN TO ABOUT 600 DM FRIDAY INTO SATURDAY.
INCREASING H85 TEMPS AND THICKNESSES WILL TRANSLATE INTO FURTHER
HEATING AT THE SURFACE. MANY SAN JOAQUIN VALLEY LOCATIONS WILL SEE
HIGHS OF 105 TO 110 ON FRIDAY AND A FEW AS HIGH AS 112 OVER THE
WEEKEND. THE RECORD HIGHS FOR FRESNO BOTH SAT AND SUN ARE 110...AND
BAKERSFIELDS ARE 112 AND 114 RESPECTIVELY. HAVE ISSUED A HEAT
ADVISORY FOR THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY AND
ADJACENT SIERRA SLOPES AS WELL AS THE KERN COUNTY DESERTS FOR
FRIDAY THROUGH SUNDAY.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...VERY STRONG HIGH
PRESSURE ALOFT OVER THE 4-CORNERS AREA SUNDAY NIGHT IS FORECAST TO
MOVE WESTWARD DURING THE PERIOD WITH SOME CONSISTENCY BY THE MEDIUM
RANGE MODELS. WITH TEMPERATURES MUCH ABOVE NORMAL AFTERNOON LAPSE
RATES TURN UNSTABLE WITH LIFTED INDICES 0 OR LESS SUNDAY AND
MONDAY. WEAK SOUTHEAST FLOW CONSISTENT IN BRINGING SOME MONSOON
MOISTURE NORTHWESTWARD AND LINGERING TO THE FIRST OF THE WEEK. WITH
THE AFOREMENTIONED AFTERNOON INSTABILITY AGREE WITH THE CURRENT
AFTERNOON CONVECTION FORECASTS FOR SUNDAY AND MONDAY.

CONTINUED VERY HIGH H5 HEIGHTS AND SFC-H5 THICKNESSES THROUGH THE
FORECAST PERIOD. WESTWARD MOVEMENT OF H5 4-CORNERS HIGH SHOULD
DECREASE AFTERNOON CONVECTIVE ACTIVITY WITH THE STRONGER ASSOCIATED
SUBSIDENCE BY TUESDAY. CURRENT FORECAST PACKAGE TO MINIMIZE ANY
ZONE-WIDE MOUNTAIN/DESERT CONVECTION MONDAY THROUGH THURSDAY.
TEMPERATURES CONTINUING MUCH ABOVE SEASONAL READINGS TO STILL
PROVIDE VERY UNSTABLE AFTERNOON LOWER LAYER LAPSE RATES. WITH SUCH
INSTABILITY ISOLATED THUNDERSTORMS STILL NOT TOTALLY OUT OF THE
REALM OF POSSIBILITY AND GRIDDED FORECASTS MAINTAIN SOME POPS OVER
SIERRA CREST TUESDAY THROUGH THURSDAY.

CURRENT WEATHER PATTERN STILL FAVORING EXTENSION OF CURRENT
TRIPLE-DIGIT MAX TEMPERATURES FOR THE KERN DESERTS AND S.J.VALLEY
THROUGH AT LEAST THE COMING MID-WEEK. EVEN IF WEEKEND MONSOONAL
MOISTURE PROVIDES CLOUD COVER AND DROPS TEMPERATURES SLIGHTLY...THE
ADDITIONAL BURDEN OF INCREASED HUMIDITY WILL STILL KEEP THE HEAT
THREAT HIGH. WITH SUCH HIGH DAYTIME TEMPERATURES DURING THE EXTENDED
PERIOD OVERNIGHT MINIMUM TEMPERATURES REMAINING RELATIVELY HIGH THUS
MAINTAINING THE DANGERS FROM THE HEAT.  GUDGEL

&&

.AVIATION...ISOLATED TO SCATTERED AFTERNOON AND EARLY EVENING
THUNDERSTORMS WILL OCCUR OVER THE HIGHEST ELEVATIONS OF THE SIERRA
AS WELL AS THE KERN COUNTY MOUNTAINS AND DESERT. OTHERWISE...VFR
CONDITIONS WILL PREVAIL THROUGH FRIDAY AFTERNOON. DUE TO
UNSEASONABLY HIGH TEMPERATURES HIGH DENSITY ALTITUDES CONTINUE TO
PREVAIL FOR THE AREA...ESPECIALLY AT THE HIGHER ELEVATION AIRPORTS.
FOR SPECIFIC DETAILS...PLEASE REFER TO TAFS FOR KMCE...KFAT...
AND KBFL.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...HEAT ADVISORY IN EFFECT FOR THE
     CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY...THE SOUTHERN SIERRA
     NEVADA FOOTHILLS...AND THE KERN COUNTY DESERTS FROM 12 PM PDT
     FRIDAY UNTIL 9 PM SUNDAY EVENING.

&&

DCH/GUDGEL
Hazardous weather outlook, Jul 20, 5:00 AM PST, 10 hours before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
600 AM PDT THU JUL 20 2006

CAZ098-099-201200-
INDIAN WELLS VALLEY-SOUTHEASTERN KERN COUNTY DESERT-
600 AM PDT THU JUL 20 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
CALIFORNIA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON AND EVENING EACH DAY
THROUGH THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS TO THE SAN JOAQUIN VALLEY NATIONAL WEATHER SERVICE
OFFICE.

CAZ089>097-201200-
WEST CENTRAL SAN JOAQUIN VALLEY-EAST CENTRAL SAN JOAQUIN VALLEY-
SOUTHWESTERN SAN JOAQUIN VALLEY-SOUTHEASTERN SAN JOAQUIN VALLEY-
MARIPOSA MADERA AND FRESNO COUNTY FOOTHILLS-TULARE COUNTY FOOTHILLS-
KERN COUNTY MOUNTAINS-SIERRA NEVADA FROM YOSEMITE TO KINGS CANYON-
TULARE COUNTY MOUNTAINS-
600 AM PDT THU JUL 20 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
CALIFORNIA.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

BINGHAM

The radar

The San Joaquin Valley radar (KHNX), 153 km away, was scanning. The volume nearest the first event began at 23:00 UTC.

Open the radar archive at this moment

Event by event

1 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Mariposa

When
July 20, 3:00 PM PST to 3:30 PM PST
Where
Mariposa County, El Portal
Measured
70 kt (81 mph) estimated gust
Property damage
$20,000
Reported by
PARK/FOREST SERVICE
Coordinates
37.683, -119.783

What these are

Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

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

The same day elsewhere

More

Every storm in California in 2006Every state in 2006This day in weather historyWarnings in California, July 2006

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: 5517559.