September– December 2024 South Ops Highlights

Southern Operations

MONTHLY/SEASONAL OUTLOOKS

ISSUED AUGUST 31 2024 VALID SEPTEMBER - DECEMBER 2024

• There is a moderate tilt in the odds towards above normal large fire potential from

September through November for all areas shaded in red.

• There is a slight tilt in the odds towards above normal large fire potential across the

South Coast for December due to the odds favoring a drier than normal fall season.

• Large fires are likely to be primarily grass dominated and fine fuels dominated.

• Due to the anomalously wet winter and spring season, there is an abnormally large

load of dead grass crop and thus a larger total fuel load than normal.

• Due to no areas of prolonged drought, larger live fuels (timber) are less susceptible

to ignition than finer fuel.

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Weather Discussion

A warm and dry pattern has persisted across central and

southern California through August. Temperature anomalies

generally ranged from 0F to 4F above normal for the

overwhelming majority of the area (Fig 1). Most of the area

saw less than 50% of the average August precipitation (Fig 2).

There are small localized areas of positive precipitation

anomalies due to intermittent monsoonal moisture resulting in

slow moving heavy shower and thunderstorms, however most

of the region remained dry. Since the beginning of our water

year (October 1

), most areas are remaining slightly to well

above average due to an anomalously wet late winter and early

spring (Fig 3).

The El Niño Southern Oscillation (ENSO) currently remains in a

neutral state due to the current transition from the El Niño to

the La Niña state. Sea Surface Temperature (SST) Anomalies

now range between 0.2

C and 0.4

C below normal in the

equatorial Pacific (Fig 4).

Fig 1: August 1

– August 30

Temperature Departure from Average

Southern Operations

MONTHLY/SEASONAL OUTLOOKS

ISSUED AUGUST 31 2024 VALID SEPTEMBER - DECEMBER 2024

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Fig 2: August 1

– August 30

Precipitation (% of Ave.)

Fig 4: Equatorial Pacific Upper-Ocean Heat Anomaly

st - October 29th Precipitation

Fig 3: October 1st – August 30th

Precipitation (% of Ave.)

Fuels Discussion

A Fuels and Fire Behavior Advisory is currently in

effect for central and southern California. Click

here to view the latest advisory.

Fuels continue to remain dry across most of central

and southern California. Latest analysis of the 1000-hr

dead fuel moisture shows 7 out of 16 Predictive

Services Areas (PSAs) have below normal 1000-hr

dead fuel moisture (Fig 5). This can be attributed to

the very dry conditions in July and August 2024 since

1000-hr fuels have the longest response time. Some

indications show the fuels are less dry at the end of

August than a month ago due to below normal Energy

Release Components (ERCs) for much of the Sierra

Mountain PSAs due to an uptick in monsoon activity

over that portion of the region (Fig 6).

Live fuel however continued to dry across the area in

August. Latest Los Padres Live Fuel Moisture values

fell to near normal, while before ran significantly

above normal (Fig 7). USDA Drought monitor shows

zero areas in drought status across central and

southern California, the only thing to note is some

abnormally dry conditions (D0) in the Central Mojave,

lower and eastern deserts (Fig 8).

There continues to remain a large load of fine dead

fuel as a result of the wetter than normal winter and

spring months which resulted in a continued active

fire season this year.

Southern Operations

MONTHLY/SEASONAL OUTLOOKS

ISSUED AUGUST 31 2024 VALID SEPTEMBER - DECEMBER 2024

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Fig 5: 1000hr Dead Fuel Moisture by PSA Map

Fig 7: Los Padres NF Live Fuel Moisture from

August 2024

Fig 4: Drought Monitor February 25th, 2021

Fig 8: USDA Drought Monitor August 27

Fig 4: Drought Monitor February 25th, 2021

Fig 6: Energy Release Components by PSA Map

Fig 5: Central Sierra 100 hr Dead fuel

moisture March 31st

SOUTH OPS OUTLOOK

Current SST anomalies and climate models suggest the continued trend towards the La Niña state of ENSO

(Fig 9 and Fig 10) which supports a warmer and drier pattern on average during the fall and winter

months for central and southern California. This trend is also reflected in the past several runs of the

various climate models. Due to the combination of weather and fuels, there is a moderate tilt in the odds

towards above normal fire potential in the Sierra Foothills, Southern Sierra, Central Coast, Central Coast

Interior, Western Mountains, Eastern Mountains, Southern Mountains and South Coast for September and

near normal potential for everywhere else in the central and southern California region. There is a slight to

moderate tilt in the odds for above normal fire potential towards the Western Mountains, Eastern

Mountains, Southern Mountains and South Coast for October and November. For December, there is a

slight tilt in the odds towards above normal fire potential for the South Coast due to an increasingly likely

dry fall and a delayed start to the wet season.

Southern Operations

MONTHLY/SEASONAL OUTLOOKS

ISSUED AUGUST 31 2024 VALID SEPTEMBER - DECEMBER 2024

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Fig 9: Sea Surface Temperature Anomaly, August

30th, 2024

Fig 10: Climate Model Predictions of the El Niño

Southern Oscillation

Current sea surface temperatures

•

https://www.ospo.noaa.gov/Products/ocean/sst/anomaly/

•

https://www.tropicaltidbits.com

Southern Operations

MONTHLY/SEASONAL OUTLOOKS

ISSUED AUGUST 31 2024 VALID SEPTEMBER - DECEMBER 2024

Maps with Counties and Select Intel Links used in the forecast

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Climate

•

https://calclim.dri.edu/pages/anommaps.html

•

https://droughtmonitor.unl.edu/

•

https://www.cpc.ncep.noaa.gov/products/NMME/

•

100 hr dead fuel moisture

•

https://gacc.nifc.gov/oscc/fuelsFireDanger_Hundred.php

November 2024

September 2024

October 2024

December 2024