The Holser Fire burned 2,142 acres across the interior valley of Ventura county, near Lake Piru. No structure damage or injuries were reported.
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 LOX wrote it up.
The Holser Fire burned 2,142 acres across the interior valley of Ventura county, near Lake Piru. No structure damage or injuries were reported.
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 Los Angeles, CA wrote its last area forecast discussion before the first event at Aug 17, 1:06 PM PST, 3 minutes earlier.
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
206 PM PDT Mon Aug 17 2020
.SYNOPSIS...17/202 PM.
Very hot conditions will continue through the week with very warm
nights, especially for valley and interior areas. Temperatures
will cool only slightly later in the week and will remain above
normal through early next week. There is a slight chance of
thunderstorms through Wednesday mostly over the mountains and the
Antelope Valley.
&&
.SHORT TERM (TDY-THU)...17/146 PM.
High pressure over Utah continues to dominate the weather,
producing very hot temps in all areas except the immediate coast
and allowing moisture from the southeast to move in and spawn
afternoon and evening thunderstorms across the interior.
Convection has been slow to develop again in LA/Ventura counties
today but some small cells have popped up around Big Bear and we
expect to see at least some convection this afternoon farther to
the west as there is ample instability, as demonstrated by the
impressive pyrocumulus plumes from both the Lake and Ranch2 fires
this afternoon. And like the last couple days there is enough
moisture to generate some brief periods of heavy rain that may
linger long enough to cause some localized flooding.
Temperatures heated up as expected across inland areas where
temps in general were up 2-4 degrees from yesterday. The primary
exception to that was the LA County coast where the absence of
southeast winds from yesterday's eddy circulation and the
proximity of the shallow stratus layer brought temps way down, in
some cases by as much as 15-20 degrees. This despite weaker
onshore gradients.
Temperatures are still expected to warm up in all areas Tuesday as
gradients weaken further and the high pressure strengthens. In
addition, some light northeast flow is expected to develop along
the Central Coast the next couple days that will help provide an
additional boost in heat and will be adding those coastal zones to
the heat advisory. The high does start to weaken Wednesday and
Thursday but not significantly enough to provide all that much
relief. It will likely take until Friday or perhaps not until
Saturday before high temps drop below advisory/warning levels.
Current slate of hazards goes through Thursday which is sufficient
for now. It's possible as monsoon moisture starts to dry up that
overnight lows will drop a few more degrees but would like to give
it another day at least before going any longer with the hazards.
The thunderstorm threat Tuesday looks similar to today, though the
strength of the high and warming aloft might hinder development.
Stability parameters are similar to today but some capping aloft
due to the warmer air might make it more difficult for storms to
develop. Models have been consistently showing less moisture and
instability Wed and Thu so thunderstorm chances are expected to
decrease later in the week.
.LONG TERM (FRI-MON)...17/201 PM.
The slow cooling trend from mid week is expected to continue into
the weekend but it remains to be seen how quickly this will
happen. Current heat advisories and warnings go through Thursday
but there is a reasonable chance that some or all of them will
need at least one additional day as the air mass remains quite
warm and onshore flow is still fairly light. In any case temps are
expected to remain at least 4-8 degrees above normal in many
areas at least through Saturday with continued slow cooling into
early next week.
The big question for the weekend is whether we're going to see a
significant push of tropical moisture from Genevieve which is in
a process of rapid intensification off the srn Mexico coast. The
GFS has gone back and forth on this and the 12z run was very much
supportive of a surge which could lead to increasing thunderstorm
chances for all areas and not just the interior. The EC remains
dry and most of the GFS ensembles were dry as well so needless to
say confidence remains low but it's something to watch as we get
closer to the weekend. There's a better chance of seeing southerly
swells from it.
&&
.AVIATION...17/1804Z.
At 1726Z, the marine layer was around 400 feet deep at KLAX. The
top of the inversion was around 3100 feet with a temp of 27C.
Areas of low clouds will affect coastal sections of Ventura
County, and immediate coastal sections of L.A. County. There is a
50 percent chance of marine clouds in KSMX Tue morning. Conds
will be mostly LIFR to VLIFR.
There is a slight chance of showers/tstms in the mtns and deserts
in the mountains and Antelope Valley this afternoon and evening.
Gusty erratic winds are possible near any thunderstorm, along
with mdt to stg uddfs.
KLAX...Low to moderate confidence in the 18Z TAF. There is a 40%
chance that cigs will not arrive tonight.
KBUR...High confidence in the 18Z TAF with VFR condition expected
through the period.
&&
.MARINE...17/151 PM.
Strong SCA level winds are expected across the outer waters this
afternoon through tonight. Gale force winds are expected in the
outer waters Tuesday afternoon through Wednesday night.
Small craft advisories are expected in the central coast inner
waters each afternoon and evening through Wednesday night.
The inner waters south of Point Conception should remain advisory
free, except for a 40 percent chance in the western SBA channel
Tue and Wed afternoon and evening.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory in effect from 11 AM Tuesday to 9 PM PDT
Thursday for zones 34-35. (See LAXNPWLOX).
Heat Advisory in effect until 9 PM PDT Thursday for zones
36-41. (See LAXNPWLOX).
Excessive Heat Warning in effect until 9 PM PDT Thursday for
zones 37-38-44>46-51>54-59-88-547. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 9 PM PDT this evening
for zone 645. (See LAXMWWLOX).
Small Craft Advisory in effect until 3 PM PDT Tuesday for
zones 670-673-676. (See LAXMWWLOX).
Gale Watch in effect from Tuesday afternoon through late
Wednesday night for zones 670-673. (See LAXMWWLOX).
&&
.HAZARD POTENTIAL OUTLOOK (THU-MON).
Triple digit high temperatures and very warm nights will bring
the potential for excessive heat over many areas Thursday and
possibly into Friday.
&&
PUBLIC...MW
AVIATION...Sweet/DB
MARINE...Sweet
SYNOPSIS...MW
weather.gov/losangeles1 wildfire. Local standard time, as filed.
The Holser Fire burned 2,142 acres across the interior valley of Ventura county, near Lake Piru. No structure damage or injuries were reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2020Every state in 2020This day in weather historyWarnings in California, August 2020
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: 915157.